book of abstracts - usc · book of abstracts edited by ignacio garcía-gonzález & manuel...

Book of abstracts

Edited by

Ignacio García-González & Manuel Souto-Herrero

Organizing Committee

Chair: Ignacio García González

Secretary: Manuel Souto Herrero

Committee members: Marta Domínguez Delmás

Dieter Eckstein

Guillermo Guada Prada

Gonzalo Pérez de Lis Castro

Tomasz Ważny

Organized by University of Santiago de Compostela

Department of Botany – Campus of Lugo

Working group on Dendrochronology and Wood Anatomy

Sponsored by

EuroDendro 2014, Lugo, Spain

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Table of Contents

EuroDendro 2014 Programme 9

Oral presentations 15

Historical dendrochronology I 15

Thomas Frank, Nadia Balkowski, Manuel Broich, Ronald Busch, Barbara Diethelm, Elisabeth Höfs, Georg Roth Which tree are you from? An approach to achieve a high probability in assigning timbers to their origin trees 15

Michael Grabner, Andrea Klein, Sebastian Nemestothy Questions about historic woodworking – answered by dendrochronology 16

David M. Brown, Michael G.L. Baillie Is there anyone there? The Irish dendrochronological framework for the period from 300BC to AD600 17

Sebastian Million, André Billamboz Seeking the last ring: Dendroarchaeological investigation on the Celtic princely tomb of Bettelbühl 18

Pascale Fraiture, Armelle Weitz, Sjoerd van Daalen Dendrochronological research on beech in Belgium: the case of 12th graves from the Nivelles Abbey (Hainaut) and future archaeological prospects 19

Rūtilė Pukienė The earliest water supply and sewage systems in Vilnius, Lithuania 20

Historical dendrochronology II 21

Marta Domínguez Delmás, Eduardo Rodríguez Trobajo Swedish borne, planks and panels: dendroarcheological investigations on the 16th century Evangelistas altarpiece at Seville Cathedral (Spain) 21

Ünal Akkemik Wood identifications of old Byzantine ships in Yenikapı (İstanbul) and wood use changes from 6th to 11th century 22

Kristof Haneca, Aoife Daly Tree-Rings, Timbers and Trees: a dendrochronological survey of two 14th-century cogs, wrecked near Antwerp (Belgium) 23

Nigel Nayling, Josué Susperregi The Newport medieval ship and development of oak ring-width chronologies in Northern Spain 24

Aoife Daly A 17th century ship with timber cargo 25

Historical and/or regional dendrochronology 26

Anne Crone Dendrochronological studies of alder (Alnus glutinosa) on Scottish crannogs 26


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István Botár, András Grynaeus, Boglárka Tóth Roofs, towers, and wood installations. Dendrodating in Transylvania (Romania) 27

Tomasz Ważny, Oliver Rackham, Jennifer Moody, Brita E. Lorentzen The Cretan Tree-Ring Project: Investigating the dendrochronological and dendroclimatological potential of the Mediterranean cypress (Cupressus sempervirens L.) 28

Katarina Čufar, Maks Merela, Michael Grabner, Willy Tegel, Martín De Luis Advances and challenges of dendrochronology SE of the Alps 29

Anna Cedro Dendrochronology of yew in Poland and western Ukraine 30

Kurt Nicolussi, Sonja Vospernik, Thomas Pichler, Herbert Formayer, Jose Groff, David Leidinger, Heinrich Spiecker Growth trends of Picea abies and Pinus cembra trees at altitudinal transects in the central Alps 31

Wood formation dynamics 32

Kyriaki Giagli, Vladymír Gryc, Hanuš Vavrčík, Ladislav Menšík Cambial activity and wood formation in European beech (Fagus sylvatica L.) growing in the Czech Republic 32

Jožica Gričar, Peter Prislan, Vladimír Gryc, Hanuš Vavrčík, Martín de Luis, Katarina Čufar Plastic and locally adapted phenology in cambial seasonality and xylem and phloem formation in Picea abies from temperate environments 33

Václav Treml, Jakub Kašpar, Hana Kuželová, Vladimír Gryc Differences in intra-annual wood formation in Norway spruce along the treeline ecotone, Giant Mountains, Czech Republic 34

Walter Oberhuber, Roman Schuster, Irene Swidrak Intra-annual dynamics of cambial phenology and radial growth reveal that species-specific climate-growth relationships are not related to different timing of maximum radial growth 35

Joana Vieira, Sergio Rossi, Filipe Campelo, Helena Freitas, Cristina Nabais Stem radial variation of maritime pine in a drought-prone environment: daily and seasonal pattern 36

Georg von Arx, Alberto Arzac, Patrick Fonti, David Frank, Roman Zweifel, Arthur Gessler, Lucia Galiano, Andreas Rigling, José Miguel Olano Spatio-temporal dynamics of non-structural carbohydrates (NSC) and radial rays in the stem sapwood of Pinus sylvestris to drought and long-term irrigation 37

Cyrille B.K. Rathgeber, Henri E. Cuny Growing is not putting on weight! 38

Novel methods in dendrochronology 39

Daniele Castagneri, Giai Petit, Marco Carrer Long cell chronologies shed new light on Norway spruce response to climate 39

Ryszard J. Kaczka, Barbara Czajka Blue Reflectance – new dendrochronological tool 40

Christian Zang, Isabel Dorado Liñán, David Frank, Emilia Gutiérrez, Annette Menzel The ecology of inhomogeneous variance in tree-ring widths 41


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Georg von Arx ROXAS – a powerful image analysis tool for tree-ring anatomy 42

Laura Fernández-de Uña, Nate G. McDowell, Isabel Cañellas, Guillermo Gea-Izquierdo Disentangling the effects of competition, climate and CO2 concentrations on tree growth and water use efficiency 43

Ecology and dynamics 44

Renata Cristina Bovi, Miguel Cooper, Mario Tomazello Filho, Matheus Peres Chagas, Renata Santos Momoli, Virgínia Dominguez Castillo Determination of erosion rates through the use of dendrogeomorphology 44

Tobias Scharnweber, John Couwenberg, Ingo Heinrich, Martin Wilmking Reactions of oak (Quercus robur L.) to a sudden peatland rewetting – implications for bog-oak research? 45

Tuomas Aakala, Frank Berninger, Mike Starr Using tree-ring based reconstruction of stand structure to assess tree growth variation in high-latitude boreal forests 46

Muhammad Waseem Ashiq, Madhur Anand Spatial variability in growth – Climate relationships of red pine in Ontario, Canada 47

Lucía DeSoto, José Miguel Olano, Vicente Rozas Female trees can grow and store more than males under favourable environments 48

Maris Hordo, Evar Dubolazov, Leevi Krumm, Andres Kiviste Climate effect to larch growth on abandoned oil shale quarries in Sirgala (Estonia) 49

Dendroclimatology 50

Ingo Heinrich, Antje Knorr, A. Bieber, Karl-Uwe Heußner, Tomasz Ważny, Michal Slowinski, Gerhard Helle, Sonia Simard, Tobias Scharnweber, Achim Brauer Climate reconstructions from tree-ring widths for the last 850 years and the need for new tree-ring proxies in northern Poland 50

Jan Esper, Paul J. Krusic, Fredrik C. Ljungqvist, Marco Carrer, Jürg Luterbacher, Rob J.S. Wilson, Ulf Büntgen Reviewing tree-ring based temperature reconstructions for the past millennium 51

Weiwei Huang, Jørgen Bo Larsen, Anders Ræbild, Lisbeth Thygesen, Jon K. Hansen The tree growth to changing climate and drought conditions in East Denmark 52

Fabio Natalini, Javier Vázquez-Piqué, Reyes Alejano Plasticity in the dendroclimatic signal of Pinus pinea in connection to climate variability within its distribution range 53

D. Ovchinnikov, A. Mordvinov, I. Kalugin, A. Darin, V. Myglan Solar-terrestrial relations of the paleoclimatic archives in the South Siberia (Altai Mountains, Russia) 54

Lea Schneider, Felix Pretis, Jan Esper, Jason E. Smerdon Detection of large volcanic events based on their climatic fingerprint in a hemispheric wood density network 55

Martin Wilmking, Allan Buras, Martin Schnittler, Jelena Lange, Kerstin Treydte, Pascal Eusemann Does tree-genetics help resolve the “divergence effect”? 56


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Markus Lindholm, Maxim G. Ogurtsov, Risto Jalkanen Common temperature signal in six proxies based on the growth of Scots pine from northern Fennoscandia 57

Posters 58

O. Nelle The view from the lake across mountains, valleys and plains: Perspectives of dendroarchaeology in a cultural heritage context 58

M. Grabner, M. Bolka, J. Tintner, M. Horsky, M. Horacek, H. Reschreiter, K. Kowarik, T. Prohaska The wooden findings of the Hallstatt saltmine – local or imported? Dendrochronology and chemical data will try to answer 59

M. Krąpiec, E. Szychowska-Krąpiec Chronology of the Lusatian Culture population stronghold in Wicina (SW Poland) in the light of dendrochronological analyses 60

K. Haneca, E. Jansma, M. Kosian A dendrochronological reassessment of three Roman vessels from the Netherlands: evidence of inland navigation between Gallia Belgica and the limes of Germania inferior 61

A. Grynaeus Dating of the roof of the Nyírbátor Calvinist Church 62

B. Tóth, I. Botár, A. Grynaeus The oldest roof structure in Transilvania 63

M. Grabner, E. Wächter, S. Karanitsch-Ackerl, M. Bolka New regional chronologies for eastern Austria – a basis for dendroprovenancing and dendroclimatology 64

A. Crespo Solana, M. Domínguez-Delmás, I. García-González, U. Sass-Klaassen, T. Ważny, N. Nayling Forest Resources for Iberian Empires: Ecology and Globalization in the Age of Discovery (ForSEADiscovery, a Marie Curie ITN project) 65

F. Campelo, J. Vieira, G. Battipaglia, M. de Luis, C. Nabais, H. Freitas, P. Cherubini Which matters most in the formation of intra-annual density fluctuations in Pinus pinaster: age or ring-width? 66

J. Gričar, Š. Jagodic, B. Šefc, J. Trajković, K. Eler Can the structure of dormant cambium and the widths of phloem and xylem increments be used as indicators for tree vitality? 67

G. Guada, I. García-González, G. Montserrat-Marti Earlywood vessel formation related to crown phenology quantified from dry mater content in Quercus pyrenaica 68

G. Pérez-de-Lis, I. García-González, V. Rozas, J.M. Olano Tree size and winter carbon storage regulate the linkage between wood formation and vessel conductivity in two ring-porous oak species 69

P. Prislan, J. Gričar, M. de Luis, K. T. Smith, K. Čufar Phenological variation in xylem and phloem formation in Fagus sylvatica from two sites in Slovenia 70


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M. Tamkevičiūtė, R. Pukienė, J. Taminskas, V. Šmatas Factors affecting daily variations of Scots pine stem size at the end of vegetation season 71

R.L. Peters, D. Frank, K. Treydte, P. Fonti Coupling stem water flow and structural carbon allocation in a changing climate: the Lötschental case-study (LOTFOR) 72

S. Klesse, D. Frank Annually resolved forest growth - first results from a Swiss dendrochronological biomass network 73

S. Bijak, A. Bronisz, K. Bronisz Is blue data better climate proxy than traditional tree-ring widths? 74

M. Grabner, S. Karanitsch-Ackerl, K. Mayer, J.-P. George, R. Klumpp, S. Schüler On the influence of drought on ring width and earlywood density of different softwood species and provenances grown in eastern Austria 75

M. Dobner Jr., M. Tomazello F° X-ray microdensitometry applied to Pinus taeda as a dendroecological data source 76

M. Souto-Herrero, I. García-González A 480-year chronology of earlywood vessels of oak in the Ancares Mountains (NW Spain) 77

R. Matisons, J. Jansons, U. Neimane, Ā. Jansons Tree-ring width, earlywood vessel area of red oak and their relationship with climatic factors in Latvia 78

M. Tomazello Filho, M. Silveira Lobão, A. Schipper Guerovich, C. I. Huaman Calderón, F.A. Roig, P.A. Zevallos Pollito A high ring-width cross-dating performance of Cedrela odorata trees from a Peruvian Amazon rainforest 79

J.A. Ballesteros-Canovas, R.J. Kaczka, B. Czajka B., K. Janecka, M. Lempa, M. Stoffel Tree ring evidence of flash flood activity in Tatra Mountains 80

M. Lempa, B. Gądek, K. Janecka, R.J. Kaczka, Z. Rączkowska Tree rings and snow avalanche modelling. Case studies from the Tatra Mountains 81

L. Chojnacka-Ożga, W. Ożga Identifying and quantifying the impact of late frost events on radial growth of common beech (Fagus sylvatica L.) from south-eastern Poland 82

K. Janecka, T. Biczyk, R. J. Kaczka Tree-ring records of volcanic influence on climate in the Tatra Mountains 83

R.J. Kaczka, K. Janecka, B. Czajka, O. Eggertsson The tree ring study of downy birch in Northern Europe 84

B. Czajka, R.J. Kaczka, A. Łajczak Dendrochronological studies of timberline changes at Babia Gora Mt., Western Carpathians 85

J. Barniak, M. Krąpiec Tree-ring analysis of sub-fossil pine wood from the Rucianka and Józefowo raised bogs (NE Poland) 86

Ł. Ludwisiak, S. Bijak The effect of black cherry understory on growth of scots pine 87


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A. Läänelaid, K. Sohar, A. Kull Detecting a buffer zone of a mire by growth release of pines 88

R. Matisons, B. Džeriņa, J. Kalniņš, Ā. Jansons Effect of climatic factors on height increment of Scots pine in Latvia 89

M. Vejpustková, A. Zeidler, T. Čihák, V. Šrámek Growth response of mountain spruce (Picea abies (L.) Karst.) to extreme climatic and pollution stress event 90

M. Peres Chagas, M. Tomazello Filho, A.P. Radaeli Neto, A. Venegas González Influence of atmospheric pollution on climate response of Poincianella pluviosa var. peltophoroides and Bignonia pentaphylla trees in Brazil 91

L. Akhmetzyanov, I. Dorado Liñán, G. Gea-Izquierdo, E. Gutiérrez, A. Menzel Climate sensitivity of Fagus sylvatica L. based on tree-ring analyses in peripheral populations in Spain 92

K. Chen, I. Dorado Liñán, L. Akhmetzyanov, A. Menzel Climate drivers of beech growth at marginal sites across Mediterranean 93

E. Martínez del Castillo, K. Novak, R. Serrano, E. Tejedor, P. Prislan, J. Gričar, L.A. Longares, M.A. Saz, K. Čufar, M .de Luis Climate-growth relationships of Fagus sylvatica and Pinus sylvestris along an altitudinal gradient in their southern distribution limits (Moncayo Natural Park, Spain) 94

J. Lousada, M. Gaspar, M. Silva, C. Besson Study of the record of meteorological data in the Pinus pinaster wood growing in Portugal 95

A. Piermattei, M. Garbarino, C. Urbinati Climate sensitivity of European black pine at the treeline in the Central Apennines, Italy 96

U. Bhuyan, C. Zang, A. Menzel Drought metrics and tree growth: matches, mismatches, and some implications for modeling continental-scale drought 97

D. Castagneri, P. Nola, R. Motta, M. Carrer Growth responses to decadal climate variations over the last 250 years pose issues on future performance of Norway spruce, silver fir and European beech 98

E. Tejedor, M. De Luis, J.M. Cuadrat, K. Novak, R. Serrano, E. Martínez, L.A. Longares, M.A. Saz Dendroclimatic and dendroecological potential of a new tree-ring database along the Iberian Range 99

K. Treydte, T. Wyczesany, D. Eamus, S. Pfautsch Using Deuterium to trace movement and storage of water in Eucalypt trees (Richmond, Australia) 100


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EuroDendro 2014 Programme

Sunday, September 7th

11:00-19:00 Dendrochronology on the street (activity for the citizens of Lugo)

Monday, September 8th

18:00-20:00 Registration

21:30 Welcome dinner

Tuesday, September 9th

9:00-9:30 Official opening

Historical dendrochronology I Chair: Kristof Haneca

9:30-9:45

Thomas Frank, Nadia Balkowski, Manuel Broich, Ronald Busch, Barbara Diethelm, Elisabeth Höfs, Georg Roth

Which tree are you from? An approach to achieve a high probability in assigning timbers to their origin trees

9:45-10:00 Michael Grabner, Andrea Klein, Sebastian Nemestothy

Questions about historic woodworking – answered by dendrochronology

10:00-10:15

David M. Brown, Michael G.L. Baillie

Is there anyone there? The Irish dendrochronological framework for the period from 300BC to AD600

10:15-10:30 Sebastian Million, André Billamboz

Seeking the last ring: Dendroarchaeological investigation on the Celtic princely tomb of Bettelbühl

10:30-10:45 Pascale Fraiture, Armelle Weitz, Sjoerd van Daalen

Dendrochronological research on beech in Belgium: the case of 12th graves from the Nivelles Abbey (Hainaut) and future archaeological prospects

10:45-11:00 Rūtilė Pukienė

The earliest water supply and sewage systems in Vilnius, Lithuania

11:00-11:30 Coffee break


9

Historical dendrochronology II Chair: Tomasz Ważny

11:30-11:45 Marta Domínguez Delmás, Eduardo Rodríguez Trobajo

Swedish borne, planks and panels: dendroarcheological investigations on the 16th century Evangelistas altarpiece at Seville Cathedral (Spain)

11:45-12:00 Ünal Akkemik

Wood identifications of old Byzantine ships in Yenikapı (İstanbul) and wood use changes from 6th to 11th century

12:00-12:15 Kristof Haneca, Aoife Daly

Tree-Rings, Timbers and Trees: a dendrochronological survey of two 14th-century cogs, wrecked near Antwerp (Belgium)

12:15-12:30 Nigel Nayling, Josué Susperregi

The Newport medieval ship and development of oak ring-width chronologies in Northern Spain

12:30-12:45 Aoife Daly

A 17th century ship with timber cargo

Introduction to poster session Chair: Gonzalo Pérez-de-Lis & Joana Vieira

12:45-13:00 Short presentations of posters

14:00-15:30 Lunch break

º

Historical and/or regional dendrochronology Chair: Niels Bonde

16:00-16:15 Anne Crone

Dendrochronological studies of alder (Alnus glutinosa) on Scottish crannogs

16:15-16:30 István Botár, András Grynaeus, Boglárka Tóth

Roofs, towers, and wood installations. Dendrodating in Transylvania (Romania)

16:30-16:45

Tomasz Ważny, Oliver Rackham, Jennifer Moody, Brita E. Lorentzen

The Cretan Tree-Ring Project: Investigating the dendrochronological and dendroclimatological potential of the Mediterranean cypress (Cupressus sempervirens L.)

16:45-17:00 Katarina Čufar, Maks Merela, Michael Grabner, Willy Tegel, Martín De Luis

Advances and challenges of dendrochronology SE of the Alps

17:00-17:15 Anna Cedro

Dendrochronology of yew in Poland and western Ukraine

17:15-17:30

Kurt Nicolussi, Sonja Vospernik, Thomas Pichler, Herbert Formayer, Jose Groff, David Leidinger, Heinrich Spiecker

Growth trends of Picea abies and Pinus cembra trees at altitudinal transects in the central Alps



10

17:30-18:30 Poster session I

19:00-20:15 Guided city tour (by courtesy of the City of Lugo)

20:30-open Official reception by the City and Province of Lugo

Wednesday, September 10th

Whole day excursion Northern Galician coastline

8:00 Departure from Lugo (Hotel Méndez Núñez)

Castro de Viladonga (Celtic ruins) and museum

As Catedrais (famous monumental beach)

San Martiño de Mondoñedo (oldest former cathedral in Spain)

14:30-15:30 Lunch (picnic on the beach at Xilloi)

A Capelada and Ortegal Cape (coastal cliffs and landscape)

20:00-22:15 Seafood dinner

23:30 Arrival at Lugo

Thursday, September 11th

Wood formation dynamics Chair: Ingo Heinrich

9:00-9:15 Kyriaki Giagli, Vladymír Gryc, Hanuš Vavrčík, Ladislav Menšík

Cambial activity and wood formation in European beech (Fagus sylvatica L.) growing in the Czech Republic

9:15-9:30

Jožica Gričar, Peter Prislan, Vladimír Gryc, Hanuš Vavrčík, Martín de Luis, Katarina Čufar

Plastic and locally adapted phenology in cambial seasonality and xylem and phloem formation in Picea abies from temperate environments

9:30-9:45 Václav Treml, Jakub Kašpar, Hana Kuželová, Vladimír Gryc

Differences in intra-annual wood formation in Norway spruce along the treeline ecotone, Giant Mountains, Czech Republic

9:45-10:00

Walter Oberhuber, Roman Schuster, Irene Swidrak

Intra-annual dynamics of cambial phenology and radial growth reveal that species-specific climate-growth relationships are not related to different timing of maximum radial growth

10:00-10:15 Short break


11

10:15-10:30 Joana Vieira, Sergio Rossi, Filipe Campelo, Helena Freitas, Cristina Nabais

Stem radial variation of maritime pine in a drought-prone environment: daily and seasonal pattern

10:15-10:30

Georg von Arx, Alberto Arzac, Patrick Fonti, David Frank, Roman Zweifel, Arthur Gessler, Lucia Galiano, Andreas Rigling, José Miguel Olano

Spatio-temporal dynamics of non-structural carbohydrates (NSC) and radial rays in the stem sapwood of Pinus sylvestris to drought and long-term irrigation

10:30-10:45 Cyrille B.K. Rathgeber, Henri E. Cuny

Growing is not putting on weight!


11:30-12:30 Poster session II

Novel methods in dendrochronology Chair: Marta Domínguez

12:30-12:45 Daniele Castagneri, Giai Petit, Marco Carrer

Long cell chronologies shed new light on Norway spruce response to climate

12:45-13:00 Ryszard J. Kaczka, Barbara Czajka

Blue Reflectance – new dendrochronological tool

13:00-13:15 Christian Zang, Isabel Dorado Liñán, David Frank, Emilia Gutiérrez, Annette Menzel

The ecology of inhomogeneous variance in tree-ring widths

13:15-13:30 Georg von Arx

ROXAS – a powerful image analysis tool for tree-ring anatomy

13:30-13:45

Laura Fernández-de Uña, Nate G. McDowell, Isabel Cañellas, Guillermo Gea-Izquierdo

Disentangling the effects of competition, climate and CO2 concentrations on tree growth and water use efficiency

13:45-14:00 Announcements of future events (EuroDendro and Fieldweek in 2015)

14:00-15:30 Lunch break

Ecology and dynamics Chair: Reyes Alejano

15:30-15:45 Renata Cristina Bovi, Miguel Cooper, Mario Tomazello Filho, Matheus Peres Chagas, Renata Santos Momoli, Virgínia Dominguez Castillo

Determination of erosion rates through the use of dendrogeomorphology

15:45-16:00 Tobias Scharnweber, John Couwenberg, Ingo Heinrich, Martin Wilmking

Reactions of oak (Quercus robur L.) to a sudden peatland rewetting – implications for bog-oak research?

16:00-16:15 Tuomas Aakala, Frank Berninger, Mike Starr

Using tree-ring based reconstruction of stand structure to assess tree growth variation in high-latitude boreal forests


12

16:15-16:30 Muhammad Waseem Ashiq, Madhur Anand

Spatial variability in growth – Climate relationships of red pine in Ontario, Canada

16:30-16:45 Lucía DeSoto, José Miguel Olano, Vicente Rozas

Female trees can grow and store more than males under favourable environments

16:45-17:00 Maris Hordo, Evar Dubolazov, Leevi Krumm, Andres Kiviste

Climate effect to larch growth on abandoned oil shale quarries in Sirgala (Estonia)


Dendroclimatology Chair: Michael Grabner

17:30-17:45

Ingo Heinrich, Antje Knorr, A. Bieber, Karl-Uwe Heußner, Tomasz Ważny, Michal Slowinski, Gerhard Helle, Sonia Simard, Tobias Scharnweber, Achim Brauer

Climate reconstructions from tree-ring widths for the last 850 years and the need for new tree-ring proxies in northern Poland

17:45-18:00 Jan Esper, Paul J. Krusic, Fredrik C. Ljungqvist, Marco Carrer, Jürg Luterbacher, Rob J.S. Wilson, Ulf Büntgen

Reviewing tree-ring based temperature reconstructions for the past millennium

18:00-18:15 Weiwei Huang, Jørgen Bo Larsen, Anders Ræbild, Lisbeth Thygesen, Jon K. Hansen

The tree growth to changing climate and drought conditions in East Denmark

18:15-18:30 Fabio Natalini, Javier Vázquez-Piqué, Reyes Alejano

Plasticity in the dendroclimatic signal of Pinus pinea in connection to climate variability within its distribution range

18:30-18:45 Short break

18:45-19:00 D. Ovchinnikov, A. Mordvinov, I. Kalugin, A. Darin, V. Myglan

Solar-terrestrial relations of the paleoclimatic archives in the South Siberia (Altai Mountains, Russia)

19:00-19:15 Lea Schneider, Felix Pretis, Jan Esper, Jason E. Smerdon

Detection of large volcanic events based on their climatic fingerprint in a hemispheric wood density network

19:15-19:30 Martin Wilmking, Allan Buras, Martin Schnittler, Jelena Lange, Kerstin Treydte, Pascal Eusemann

Does tree-genetics help resolve the “divergence effect”?

19:30-19:45 Markus Lindholm, Maxim G. Ogurtsov, Risto Jalkanen

Common temperature signal in six proxies based on the growth of Scots pine from northern Fennoscandia

19:45-20:15 Closing ceremony

21:30-open Farewell dinner


13

Friday, September 12th

9:00 Departure


14

Which tree are you from? An approach to achieve a high probability in assigning timbers to their origin trees

T. Frank1, N. Balkowski1, M. Broich1, R. Busch1, B. Diethelm1, E. Höfs1, G. Roth2 University of Cologne, Germany

1 Institute of Prehistoric Archaeology - Laboratory of Dendroarchaeology; 2 Institute of Ethnology - study project ‘Environmental Archaeology’

The question ‘Which timbers originate from the same tree?’ aims for insights into historic timber economics and construction processes. Here it is addressed to wooden linings from early Neolithic wells excavated in the Rhineland region in Western Germany. Neolithic wooden relics, especially from the early Neolithic Linear Pottery Culture (LBK, 5500 to 5000 BC), are very rare in Central Europe. In the Rhineland wooden samples from three early Neolithic well sheetings excavated in Erkelenz-Kückhoven (EK, n=86), Arnoldsweiler (AW, n=36) and Merzenich-Morschenich (MM, n=24) have been dendrochronologically analysed. The felling dates of the youngest trees are 5090 BC (EK, waney-edge), 5097±10 BC (AW, sapwood, preliminary date) and 5052±5 BC (MM, sapwood). Nearly all boards of the linings are made of oak (Quercus spp.) and only dated tree-ring series from this species are used for the analysis. A data set from recent trees serves to check the reliability of the results. We apply two established approaches to analyse the tree-ring width sequences in regard to their common origin.

1. Visual comparison of the growth-curves and statistical analysis of their correlations (e.g. Tegel et al. 2012).

2. The ‘dendro-allocation’ by Mom et al. (2011). Starting from Mom et al. (2011) one of us (GR) refined some aspects of the computation using the package vegan (Oksanen et al. 2013) written in the statistical computing language ‘R’ (R Core Team 2012). The results of this procedure are checked against those of the above mentioned approaches. An R-code for the analysis can be provided by GR.

REFERENCES

Mom, Vincent; Schultze, Joachim; Wrobel, Sigrid; Eckstein, Dieter (2011): Which timbers were cleft from the same tree? In: Wolfgang Börner (ed.): 15th International Conference on "Cultural Heritage and New Technologies" Vienna, 15.-17. November 2010 // Proceedings. Vienna: Museen der Stadt Wien, Stadtarchäologie, 582–591. Oksanen, Jari; Guillaume Blanchet, F.; Kindt, Roeland; Legendre, Pierre; Minchin, Peter R.; O’Hara, R. B.; Simpson, Gavin L.; Solymos, Peter; Stevens, M. Henry H.; Wagner, Helene (2013): vegan: Community Ecology Package. R package version 2.0-8. [http://CRAN.R-project.org/package=vegan]. R Core Team (2012): R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. ISBN 3-900051-07-0. [http://www.R-project.org]. Tegel, Willy; Elburg, Rengert; Hakelberg, Dietrich; Stäuble, Harald; Büntgen, Ulf (2012): Early Neolithic water wells reveal the world’s oldest wood architecture. PLOS One 7: 1–8. doi: 10.1371/journal.pone.0051374.


15

Questions about historic woodworking – answered by dendrochronology

M. Grabner, A. Klein, S. Nemestothy University of Natural Resources and Life Sciences Vienna - BOKU, Vienna, Austria

Dendrochronological dating can provide precise dates on a calendar-year basis. In some cases, a differentiation between growth period and winter time is possible. But what is the significance of these dates? The importance of the waney edge (Waldkante, bark ring) as well as the presence/absence and the amount of sapwood have often been discussed. Dealing with historical wood utilization, questions about wood working arise. At which time of the year were the trees felled? When were they trifted and floated? At which condition were the logs transformed to beams and how long where they dried prior to setting up? How long was the seasoning time of timber to produce furniture? How many rings were lost due to wood working? At the prehistoric salt mine of Hallstatt, 88% of the mining timber (572 round logs) were felled during winter. Their outermost ring shows complete latewood and 63% of these logs still have bark on them. Just two percent were felled during the growing season. Studying hundreds of samples from Austrian log houses, just two percent of the samples were felled in summer (incomplete latewood) within the alpine region. At houses situated at the alpine foothills four percent showed incomplete latewood. Working marks for counting the beams can be easily found at roof constructions. Sometimes it is obvious, that the crack due to drying of the wood separated the marks into two pieces. Therefore, the crack must have appeared after carving the marks. As wood working (with the broad axe) was done on fresh wood, the cutting to length and the mortise of connections must have been done prior to cracking, too. In historic Vienna, the completion of a building had to be officially announced as soon as the facade was ready. Archive studies of these announcements revealed that they were often submitted two years after the felling dates of the roof beams. This two-years-gap (varying between one and five to seven years) includes the time of trifting, floating, hewing, setting up the roof construction and finishing the facade – another proof, that the wood was used in fresh conditions. Dating furniture does usually not provide waney edges. 947 pieces from furniture, casks and vats from Austrian farm houses were dendrochronologically dated. For every object, as many elements (boards or staves) as possible were measured. Due to the grouping of the dated outermost ring, it was possible to get an educated guess of the felling dates. For example, a cupboard painted with the calendar year 1819 was dated at 1814. This five-years-gap was due to drying and due to wood loss; proofing short drying durations and that as little as possible of the high-quality outermost wood was removed. Questions about historical wood working are more complex to answer than the question about the felling date alone, but dendrochronology can be a tool to answer these questions. Supported by the Austrian Science Fund FWF TRP 21-B16.


16

Is there anyone there? The Irish dendrochronological framework for the period from 300BC to AD600

D.M. Brown, M.G.L. Baillie School of Geography, Archaeological and Palaeoecology, Queen’s University Belfast, Belfast, United

Kingdom

In Ireland, the period from the Middle Iron Age, based on the first appearance of the La Tène art style, through to what is now called the Early Middle Ages, includes some of the most puzzling centuries in the whole of Irish history. In this paper we will look at several strands of information that have become available from dendrochronological analysis. The interpretation of dendrochronological results works best when there is other data and information to exploit. In this period one of the best sources of parallel information has to be records of atmospheric chemistry. This information has been obtained from the ice cores drilled at various locations across Greenland. Integrating this well dated climate information with evidence from precisely dated tree rings, palaeoecological studies, and occasionally from history, allows us to outline a series of events that form the beginnings of an understanding of this period. The dendrochronological results can be summarized by a notable building pulse of trackways and ritual sites in Ireland, which characterizes this stage of the Iron Age, from about 160BC to 40BC. Evidence after 50BC from ice records and other evidence from Swedish and bristlecone pine frost rings suggests that whatever happened environmentally put a stop to this building phase of trackways in Ireland’s raised peat bogs. Following 40BC we see no dendrochronologically dated structures until after AD400, except for a few random worked wood samples. The Irish “Iron Age Lull” is just not confined to dendrochronological dating. The massive reduction in archaeological activity and the significant decline in radiocarbon dated sites indicates a reduction in all forms of activity implying a significant decline in population numbers. This low level activity is incomplete contrast to the massive pulse of building in the 1st and 2nd centuries BC. It is also in notable contrast to the great phase of construction with oak timbers after AD540 following the acute double environmental events in AD536 and AD540-543. The outline of Irish archaeology between a few hundred years BC and a few hundred years AD is now well defined. What is required are new strategies to ascertain the environmental, economic and social events that were going on during this period. However, even with two further decades of the most intense archaeological sampling ever completed in Ireland it has been possible to add very little to the overall archaeological story.


17

Seeking the last ring: Dendroarchaeological investigation on the Celtic princely tomb of Bettelbühl

S. Million, A. Billamboz Landesamt für Denkmalpflege Baden-Württemberg, Hemmenhofen, Germany

In 2010 an archaeological team of the Landesamt für Denkmalpflege (coordination D. Krausse) began with the re-excavation of an already known Iron Age burial mound at Bettelbühl (Herbertingen, SW Germany). The site is situated on the ancient riverbed of the Danube at the foot of the oppidum Heuneburg. A well-preserved wooden chamber tomb was found with several evidences for a burial with peculiar goods and ornaments of two women. For this reason, the complete funeral was transferred at the end of the same year to a dry and safe place for an indoor-excavation (see Fernández-Götz & Krausse 2013). The chamber was principally built of oak wood (Quercus sp., 21 elements preserved), with exception of two silver fir beams (Abies alba Mill.) in the floor. Two sleeper beams, eleven floor beams and ten mainly badly preserved wall or ceiling boards are the remaining timbers of the whole grave. A first dating, obtained from on site coring of oak heartwood with an increment borer, indicated a construction from the very beginning of the 6th century BC. Within four years, systematic sampling (55 samples) had been conducted for tree-ring analysis parallel to the excavation progress. Particular attention has been paid to conserved sapwood and waney edge below bronze findings. Finally, a silver fir beam revealed the “last ring under the bark” in the second decade of the 6th century BC by contact with metal. Cross-dating the 102-rings long silver fir sequence with those of the Heuneburg-Vorburg is supported by strong Gleichläufigkeit and the same felling date. The result is in agreement with the parallel dating of the 288-years long oak site chronology.

Oak dendrotypology (timber categorisation according to cambial age, growth patterns and degree of stem conversion) shows the use of four to five oak trees having grown in different environments. This raises the question of a possible reduction of oak timber sources in relation to landscape opening at the end of a flourishing settlement expansion around the Heuneburg during the 7th century BC. This observation is supported by the supply of silver fir, a rather rare tree-species in the nearby region. Consequently, dendro-provenancing was addressed in cooperation with S. Ponton (INRA, Nancy-Champenoux, France) by measuring the mineral content of the xylem on the two silver fir beams. Futhermore, oak vessel analysis was conducted in cooperation with P. Fonti and G. von Arx (WSL Birmensdorf, Switzerland) for anatomical comparison on four samples assigned dendrotypologically to different trees.

REFERENCES

Fernández-Götz, M. & Krausse, D. (2013). Rethinking Early Iron Age urbanisation in Central Europe: the Heuneburg site and its archaeological environment. Antiquity 87: 473-487.


18

Dendrochronological research on beech in Belgium: the case of 12th graves from the Nivelles Abbey (Brabant wallon) and future

archaeological prospects

P. Fraiture1, A. Weitz1, S. van Daalen2 1 Royal Institute for Cultural Heritage, Brussels, Belgium

2 van Daalen dendrochronologie, Deventer, The Netherlands

In 2011-2013, the Royal Institute for Cultural Heritage was entrusted with the dendrochronological analysis of approximately one hundred planks from the graves of two zones of cemeteries that were excavated on the grounds around the Nivelles Abbey by the Archaeological Service of the Service Public de Wallonie (SPW-DGO4). These planks, mostly in beech (Fagus sylvatica), have been well preserved for almost ten centuries, in the humid subsoil of the Grand Place. The objectives of the dendrochronological research were several:

- Find relative dating between planks/graves/cemeteries - Date absolutely the graves/cemeteries - Enrich the technical study of the wooden graves - Bring information on the beech forests which supplied Nivelles cemeteries - Locate the provenance zones of these beeches.

The project encountered a huge initial challenge, as hitherto there was no historical beech chronology available for Belgium (and more generally few for western Europe). A second challenge was to record reliable tree-ring series on planks made of a species that can form partial rings (ring which are not visible on the whole circumference of the trunk). From a practical standpoint, these two challenges brought with them many difficulties. However, they were largely surpassed and yielded interesting and original results; this paper will present our main conclusions. Relative dating between the woods reveals some contemporaneity between the graves and absolute dating determined periods of intense use of both cemeteries, in terms of termini post quem. Furthermore, the dating of these wooden samples has allowed for the construction of the first beech chronology for Belgium, running from 902 to 1149 AD. Although the delivered planks were selected to be best suited for dendrochronology, technical information could be obtained from this material, for instance the growth rhythm of the trees, cutting methods, identification of planks from the same tree(s), either in the same grave or in different ones, etc. The research of the geographical origin of the trees used in Nivelles reveals – at first sight – a local provenance of the beech, although it seems difficult to locate it precisely due to the response of Fagus to local climatic conditions, in opposition to species such as oak. Forest management is being studied, with the help of agronomists and forest historians. It shows many different patterns in the growth of the trees that probably reflect different growth environments, those having still to be better described. Since this study, other projects on archaeological remains from different sites in Belgium, ordered to van Daalen dendrochronologie, have been undertaken, which have led to good results and have allowed for extending this beech chronology of a century back in past.


19

The earliest water supply and sewage systems in Vilnius, Lithuania

R. Pukienė1,2 1 Vytautas Magnus University, Kaunas, Lithuania

2 National Museum the Palace of Grand Dukes of Lithuania, Vilnius, Lithuania

Due to the high groundwater level, a number of wooden underground objects had remained in the Vilnius Lower Castle territory from different periods. Dendrochronological investigation of ancient infrastructure elements helped to determine more accurately the building and maintenance history of this most central part of Vilnius. Among the key needs of living in densely populated areas are water supply and sewage management. During archaeological investigation of the castle elements of wooden water supply system and sewers were found. Two types of finds were discovered during archaeological excavations of the site that were related to the underground water-supply network. They were wooden water pipes and their remains, as well as the metal couplings used to join them. Wooden water pipes were made from pine logs, with the central part hollowed by a long auger. The diameter of the pipes ranged from 25 to 40 centimeters and their length measured 9 meters. The pipes were joined to one another using iron cylinder-shaped couplings with diameters of 11 to 17 centimeters and length of 10 to 13 centimeters. The beginning of water pipeline network is dated back to 1501 by arguable historical sources in Vilnius. The earliest remaining wooden water pipes found in the Lower Castle were dendrochronologicaly dated to 1529. This first pipeline supplied with water the newly built grand duke’s palace. In the 1540s–1550s major development of the water-supply system in the Vilnius Lower Castle occurred. Pipes were dated to 1545, 1551 and 1558. During the reign of grand duke Sigismund Augustus (1544-1572), water flowed into the most important buildings of the castle. In 2002 and 2008 also parts of a wooden sewer were discovered north of the grand duke’s palace. The sewer was meant for kitchen waste and was assembled in sections. Each section consisted of a flume made up of four sawn longitudinal boards resting upon cut out sections of log mudsills and covered by transversal boards. There are rafting holes in some of mudsills. The covers of the sewer were made from oak and the rest parts – from pine timber. An 83 year-long oak tree-ring series was dated to 1530 against English oak chronology of the Baltic origin BALTIC1; however, some external rings were missing. After investigation of pine parts, tree-ring series with the duration of 248 years was made. The mudsills were preserved up to the bark edge. The constructed pine tree-ring series was dated against Vilnius pine chronology to 1539. Since the last ring is a bark-edge one, the dating shows the trees for the sewer were felled in the period from autumn of 1539 to spring of 1540. Dendrochronological analysis of remnants of water supply and sewage systems has revealed the 16th c. was the time of rapid development of conveniences and sanitary in Vilnius.


20

Swedish borne, planks and panels: dendroarchaeological investigations on the 16th century Evangelistas altarpiece at Seville

Cathedral (Spain)

M. Domínguez-Delmás1a, E. Rodríguez-Trobajo2 1 University of Santiago de Compostela, EPS, Dep. of Botany, Campus de Lugo, 27002 Lugo, Spain;

University of Huelva, Faculty of Humanities, Dep. of History I; Av. de las Fuerzas Armadas s/n, 21007 Huelva, Spain

2 Centro de Investigación Forestal, Instituto Nacional de Investigaciones Agrarias, Crta. La Coruña km. 7.5, 28040 Madrid, Spain

The results of the dendroarchaeological research carried out on the 16th century altarpiece from the Evangelistas chapel at Seville Cathedral (Spain) are presented. The altarpiece consists of nine panels and was commissioned from the Flemish artist Hernando de Esturmio in AD 1553, who signed the completed work in AD 1555. The research aimed at i) registering information about the processing of the wood and panel making, ii) verifying the AD 1555 construction date, and iii) finding out the provenance of the wood. The observed technological features in the five researched panels allowed the reconstruction of the production process from borne (oak wainscots) to the final product and, based on that, two types of panels were identified. However, dendrochronological research showed that the wood employed represents a rather homogeneous group that originates from the same area, implying that the raw material was probably transported to Seville in the same batch, and was prepared and assembled using slightly different techniques to meet the requirements stipulated by the contract. Sapwood was identified in 12 of the 33 planks selected for research from the five panels. Using a Bayesian approach we estimated the felling date of the trees between AD 1549 and 1553. Interestingly, our research provides evidence that the wood originated from the southwest of Sweden, representing an alternative source to the south-eastern Baltic oak commonly used for art pieces in northern Europe. This is the first time that such procurement source is reported by dendrochronology in an altarpiece. Wood technological features observed in the panels are compared to those of contemporary altarpieces in Spain and Portugal, and possible reasons for the use of this alternative procurement source are discussed.

a Affiliation at the time of the research: Ring Foundation (Stichting Ring) – Netherlands Centre for Dendrochronology, PB 1600, 3800BP Amersfoort, The Netherlands


21

Wood identifications of old Byzantine ships in Yenikapı (İstanbul) and wood use changes from 6th to 11th century

Ü. Akkemik İstanbul University, Faculty of Forestry, Department of Forest Botany,

34473 Bahçeköy – İstanbul, Turkey

Archaeological excavations in Yenikapı revealed valuable information about the human life and trade for Byzantine period. The biggest ship archive in the world was obtained by excavating 37 wooden ships from that area. We studied 27 of them and the identifications on the latest one (YK37) will not be started yet. The purpose of this study is (1) to identify the woods of the 27 ships (24 trade ships and the rest 4 galleys) from Byzantine period, (2) to investigate the wood use change from 6th century to 11th, and (3) to find possible origins of the ships. Because of being very soft wood pieces, the thin sections were taken by using very sharp razor blades, and by using standard wood identification techniques, 3122 (619 from the galleys and 2503 from the trade ships) wood samples from 27 ships were identified. In the galleys; (1) Black pine, Taurus cedar, and Spanish chestnut were used in building of planking, (2) Oriental plane and Elm trees were preferred as floor timber, (3) Keels were Oriental plane and oak trees, and (4) Treenails were Spanish broom and oak. In trade ships; (1) during 5th-6th centuries Cypress, Calabrian pine, Stone pine, Black pine and red oak were used in building of planking. During 7th to 9th centuries a similar wood use was observed. On the contrary, after 9th century and during 10th – 11th centuries mainly White oaks and Chestnut were used, (2) a few samples of ceiling from 9th – 11th centuries were founds. The wood use is about the same with that of planking, (3) in building of keel a periodical change was not observed. White oak, Red oak, beech, Oriental plane, Stone pine, Calabrian pine and Mediterranean cypress were used in different times. However, use of gymnosperm woods was also left in later centuries like in that of planking and ceiling. Oak, pine, chestnut, beech, hornbeam and plane trees were used in the trade ships during 6th century to 11th century, (4) when Stone pine, Calabrian pine, White oak, Red oak, Evergreen Oak, ash and elm trees were used during 5th-9th centuries, only White oak and Ash woods were identified in the floor timber/futtock during 9th-11th centuries, and (5) in making of tree nails Oak and Spanish broom were used. A very clear change in wood use was observed from earlier time (5th - 6th) to later (7th - 9th and10th – 11th). During 6th–8th centuries generally conifer woods were preferred. Later, during 9th – 11th broad-leaved trees (elm, oak, chestnut species) had been used. The reasons of this change may be (1) Preferring more resistant woods and (2) Obtaining possibilities the wood material. Conifer trees (especially Mediterranean cypress) in earlier ships might be from the planted areas by the Bosporus. Because historical records showed some plantations were made with this species. Later to 11th century completely broad-leaved trees were used and these probably were from northern forests of Istanbul. Because all the main woods used in the ships were (are still) native to the northern forest of Istanbul and represented with good quality stems. Most of the ships have also very low number of different woods such as walnut, poplar and hornbeam. These woods may indicate some small repairs in the ships. Because taking big samples are forbidden and the woods are very soft, we could not perform dating of the old ships with dendrochronology methods.


22

Tree-rings, timbers and trees: a dendrochronological survey of two 14th-century cogs, wrecked near Antwerp (Belgium)

K. Haneca1, A. Daly2 1 Flanders Heritage Agency, Brussels, Belgium

2 Dendro.dk, Brønshoj, Denmark

In 2000, the remains of a cog, Doel 1, were found in Doel, Belgium. Two years later, the remains of a second cog ship were found nearby. Wood species identification of all ship timbers and smaller elements was performed. European oak was the dominant species, followed by alder that was used for the fairings of Doel 1. In total 150 ring-width series were recorded on Doel 1 and 27 on Doel 2. The construction date for Doel 1 was set at AD 1325/26 and the timbers proved to originate from forests along the rivers Elbe and Weser. For the bottom strakes a strict symmetrical layout was observed. The keel plank was hewn from a trunk with potentially a slightly earlier felling date. Repairs were performed with high-quality boards, some with a southern Baltic provenance. Although contemporary (the felling date for Doel 2 is situated between 1327 and 1341 AD) a completely different wood provenance was found for Doel 2. All investigated ship timbers originate from trees growing in northern Poland. Some of the repair planks were probably inserted some years after the construction of the ships, as is supported by the tree-ring dating. The dendrochronological research on both ships not only provides accurate dates for their construction, but also on wood procurement, shipbuilding techniques and the level of professionalism of the shipwrights. Furthermore, given the extensive tree-ring dataset that was built up during this research project, guidelines regarding sampling strategy of similar ship finds can be formulated.


23

The Newport medieval ship and development of oak ring-width chronologies in Northern Spain

N. Nayling1, J. Susperregi2 1 University of Wales Trinity Saint David, Lampeter, Wales

2 Arkeolan Foundation, Laboratorio de Dendrocronología, Irun (Gipuzkoa), Spain

The Newport Ship is the most substantial late medieval vessel excavated and recovered in Britain in recent years. It was abandoned after extensive salvage, possibly following attempts at repairs to the hull. More than 23 metres of the clinker-built ship were recovered, along with significant artefact and environmental assemblages. Finds point to strong Iberian connections during the active life of the ship, which arrived in Newport, in the Severn Estuary, after the spring of AD 1468 (Nayling and Jones 2014). At the time of the discovery of the ship, it proved impossible to date the timbers used in its original construction through the application of dendrochronology. Associated British timbers and artefacts provided dating to the mid-fifteenth century. The development of regional oak ring-width chronologies in the Basque Country, and their extension back in time to overlap with the ring-width mean developed for the Newport Ship has allowed absolute dating and provenance of the timbers used in the ship’s original construction (Nayling and Susperregi 2014). Further research is required to both clarify the source of the ship’s timbers and provide a network of tree-ring data for the region for the dating and analysis of other historic assets including ship finds originating in the Basque Country.

REFERENCES

Nayling, N. & Jones, T. (2014). The Newport Medieval Ship, Wales, United Kingdom International Journal of Nautical Archaeology: Early View. Nayling, N. & Susperregi, J. (2014). Iberian Dendrochronology and the Newport Medieval Ship International Journal of Nautical Archaeology: Early View.


24

A 17th century ship with timber cargo

A. Daly Dendro.dk, Copenhagen, Denmark and Statens Museum for Kunst, Copenhagen, Denmark

A shipwreck, recently found at the mouth of the River Elbe in Northern Germany was identified and documented by Martin Segschneider, Archäologisches Landesamt Schleswig-Holstein, in 2013. The dendrochronological analysis has shown that the ship is from timber felled in AD 1618. While the timbers from the ship itself, through provenance determination, can be shown to be from trees that grew in Schleswig-Holstein, Northern Germany, the ship’s large cargo of oak timber, by contrast, originated from the Southern Baltic region. The timber cargo consists of two standard timber dimensions, and adds yet another piece to the large knowledge we have, through dendrochronology, of the extensive so-called Baltic timber trade over many centuries. With the extensive evidence for trade in timber available through archaeological finds and historical documents, how can we utilise the dendrochronological evidence to increase our knowledge of the extent and mechanisms of trade in timber through the region through time? In this talk I will present the dendrochronological analysis of the Elbe ship and cargo, and try to draw a picture of other insights that the dendrochronological dataset is providing, for timber trade across Northern Europe.


25

Dendrochronological studies of alder (Alnus glutinosa) on Scottish crannogs

A. Crone AOC Archaeology Group, Edinburgh, Scotland

On most Scottish crannogs that have been investigated alder is the species most extensively used for construction and therefore has the potential to provide fine chronological resolution for these sites. Dendrochronological studies of alder have now been undertaken on three crannogs, with mixed results. On the Early Historic crannog at Buiston, Ayrshire the construction of a single comprehensive alder chronology has contributed significantly to the overall chronology of the crannog, whereas on the later prehistoric crannogs at Oakbank, Perthshire and Cults Loch 3, Dumfries & Galloway it was only possible to construct numerous small chronologies which have limited value for chronological resolution on the sites. Comparison between the datasets suggest that factors such as the structure of the parent tree, ie whether it comes from multi-stemmed coppice or single maiden trees, as well as the presence of multiple sources are likely to be a significant factors in the successful dendro-dating of the species. These observations will be tested this summer on a fourth assemblage of alder, from a later prehistoric loch village at the Black Loch of Myrton, Dumfries & Galloway, and will be reported in this paper.


26

Roofs, towers, and wood installations. Dendrodating in Transylvania (Romania)

I. Botár1, A. Grynaeus2, B. Tóth3 1 Csíki Székely Múzeum, Csíkszereda, Romania

2 Hungarian Dendrochronological Laboratory, Budapest, Hungary 3 University of Szeged, Szeged, Hungary

Systematical collection of dendrochronological samples from historical structures and archaeological sites in Transylvania started in 2003 thanks to a Hungarian project. This research leaded to the founding in 2008 of the Transylvanian Dendrochronological Laboratory which since then continuously focuses on dating local historical wood structures and installations. Due to this work we can use two main chronologies for oak and silver fir materials from the 14th-20th centuries so dendro dating became a routine in the last years. Thanks to regular appearances in conferences and publications the method is finally accepted and more and more required by architects before and during restoration processes of monuments. Beside building dates dendrochronology has a important contribution to the typology of the roof structures and also for reconstructing some effects of historical events such as Turkish invasions. The main purpose for the future is to enlarge the validity of our chronologies both geographically and chronologically towards the firs millennium and the Carpathians. The presentation will present some examples of these researches regarding medieval roofs, reconstructions, and dated ecclesiastical installations


27

The Cretan Tree-Ring Project: Investigating the dendrochronological and dendroclimatological potential of the Mediterranean cypress

(Cupressus sempervirens L.)

T. Wazny1,2, O. Rackham3, J. Moody4, B.E. Lorentzen1 1 University of Arizona, Laboratory of Tree-Ring Research, Tucson, AZ, USA

2 Nicolaus Copernicus University, Institute for the Study, Conservation and Restoration of Cultural Heritage, Torun, Poland

3 Cambridge University, Corpus Christi College, Cambridge, UK 4 University of Texas at Austin, Department of Classics, Austin, TX, USA

The east Mediterranean cypress (Cupressus sempervirens), which grows in the mountains of Crete, includes some of the oldest (if not the oldest) trees in Europe. These ancient trees are promising material for dendrochronological and dendroclimatological research. Crete also preserves many medieval buildings, abandoned settlements and archaeological sites which have the potential to link the chronologies of living trees to ancient timbers, lengthening the tree-ring record. Previous attempts to extract a meaningful record from Cretan cypresses were hampered by irregular and missing rings, and less sophisticated techniques than are available today. For these reasons we launched the Cretan Tree-ring Project to investigate the dendrochronological potential of Crete and the east Mediterranean cypress in particular. Tree-ring series representing high-altitude cypress trees were assembled into a 900 year Cretan cypress chronology, from the present to AD 1110, confirming the suitability of this tree for dendrochronology. This cypress chronology was verified by perfect cross-dating with junipers from the Antalya region in Turkey. The next segment of the cypress chronology based on trees with over 900 rings is in development. Study of timbers from abandoned buildings has revealed the presence of imported timbers even in the heart of cypress and pine timber country. The Cretan Tree-Ring Project will help illuminate the economic landscape and environmental fluctuations of this highly interesting island.


28

Advances and challenges of dendrochronology SE of the Alps

K. Čufar1, M. Merela1, M. Grabner2, W. Tegel3, M. De Luis4 1 University of Ljubljana, Biotechnical Faculty, Department of Wood Science and Technology,

Ljubljana, Slovenia 2 University of Natural Resources and Life Sciences, Vienna, Institute of Wood Technology and

Renewable Resources, Tulln, Austria 3 University of Freiburg, Institute of Forest Sciences, Freiburg, Germany

4 University of Zaragoza, Department of Geography and Regional Planning, Zaragoza, Spain

We intend to present recent advances and challenges of dendrochronological research in Slovenia and the surrounding areas, based on several studies in trees and objects of cultural heritage. Recent dendroecological investigations of 41 local tree-ring chronologies of oak (Quercus sp.) from Austria, Hungary, Slovenia, Croatia and Serbia, where we used principal component analyses, showed that agreement of residual chronologies could be resumed in 11 significant principal components (PC). Three of them made it possible to identify similarities among the sites. PC1 was significantly correlated with all investigated chronologies. It indicated a common positive response to precipitation in March and June and a negative response to temperature in April and June. PC2 (significantly correlated with 12 chronologies), indicated a common positive response to precipitation in May and a negative one to high temperatures in August with a pronounced north to south gradient. PC3 (significantly correlated with 10 chronologies) indicated that a warm previous December and warm current September have a positive effect on tree growth, especially in the south-western part of the study area (Čufar et. al. 2014a). These results are important for improvement and prolongation of chronologies, which are still scarce in the region. In Slovenia, the prolongation of the ca. 550 years long regional oak chronology progresses slowly. The extensive investigations of the constructions in the castle Pišece gave only few samples with tree-rings formed before 1450, although the castle has more than 800 years long history. On the other side, archaeological excavations of medieval Ljubljana helped us to collect waterlogged oak wood and construct a chronology spanning the period 1172-1413. This chronology could be dated with several chronologies from western Europe. Excavations in Roman Emona and Nauportus (present day Ljubljana and Vrhnika) helped us to obtain material for silver fir (Abies alba) of the 1st centuries BC and AD which could be dated by means of teleconnection. On the other hand, beech (Fagus sylvatica) constructions from the same period could be dated with help of heteroconnection with silver fir. A barge for river transport made of beech-wood is currently the most valuable dated wooden artefact from the Roman period in Slovenia. It has been dendrochronologically dated with a post quem end date of AD 3 (Čufar et al. 2014b). Also the combined chronology of seven pile dwellings at the Ljubljansko Barje, Slovenia, spanning the period 3771-3330 BC, has been recently absolutely dated. Finally we would like to discuss some challenges of dendrochronological research in Europe, which have been recently addressed by different communities (like COST action Wood Musick) which depend on the support of dendrochronology.

REFERENCES

Čufar, K., Merela, M., Erič, M. (2014a). A Roman barge in the Ljubljanica river (Slovenia): wood identification, dendrochronological dating and wood preservation research. Journal of Archaeological Science, 44: 128-135 DOI 10.1016/j.jas.2014.01.024. Čufar, K., Grabner, M., Morgos, A., Martinez Del Castillo, E., Merela, M., De Luis, M. (2014b). Common climatic signals affecting oak tree-ring growth in SE Central Europe. Trees: DOI 10.1007/s00468-013-0972-z.


29

Dendrochronology of yew in Poland and western Ukraine

A. Cedro Laboratory of Climatology and Marine Meteorology,

Institute of Marine Sciences, Faculty of Geoscience, University of Szczecin, Poland

The study concerns dendrochronology and -climatology of the yew growing in Poland and in western Ukraine (Kniaźdwór, one of the species’ richest stands in Europe). The yew (Taxus baccata L.), a long-lived, slowly growing tree, is regarded as a species threatened with extinction. The eastern boundary of its range transects Poland. The analyses were performed on 35 yew populations which are protected as parts of nature reserves, as monuments of nature, or which are planned to be protected. Samples were collected with the Presslar borer from 25 trees in every area studied. The samples were collected from a total of 797 trees yielding 1348 profiles. Analysis of pointer years and the response function performed for local and regional chronologies pointed to a dominant role of temperature in December of the year preceding growth as well as that of January, February, and March of the year of growth (linear relationships). Precipitation in June was an additional factor affecting the tree ring width in some areas of N and NW Poland: the higher the precipitation, the wider the tree ring. Teleconnections examined for the regional yew chronologies and the four available European and one Georgian ones showed the highest similarity to exist between chronologies from southern England and those from N, NW, and central Poland. Heteroconnections examined for the regional yew chronologies from N, NW, and central Poland showed the highest similarity to exist between the yew and the Douglas fir sequences, followed by the similarity between the yew series and that of the Scots pine. The results obtained, particularly those concerning growth-climate relationships and dendroclimatic regionalisation, can be used in the on-going programme of yew restitution in Poland. Seed acquisition, growing of seedlings, and yew planting should be closely associated with characteristics of a region. Multiplication of individuals of unknown provenance, of those originating from populations of low genetic diversity, and of trees obtained from varieties, hybrids, or lateral saplings should be discouraged.


30

Growth trends of Picea abies and Pinus cembra trees at altitudinal transects in the central Eastern Alps

K. Nicolussi1, S. Vospernik2, T. Pichler1, H. Formayer3, J. Groff2, D. Leidinger3, H. Spiecker4 1 Institute of Geography, University of Innsbruck, Innsbruck, Austria

2 Institute of Forest Growth, University of Natural Resources and Life Sciences, Vienna, Austria 3 Institute of Meteorology, University of Natural Resources and Life Sciences, Vienna, Austria

4 Institute of Forest Growth, Albert-Ludwigs-University Freiburg, Freiburg, Germany

Tree-ring growth of trees in mountainous areas is potentially determined by topographical circumstances, i.e. elevation and aspect, beside endogenous and climatic factors. The relevance and variability of the different controlling variables on growth of trees in an alpine landscape is an open question especially with regard to scenarios of future climate change. Here we analyze some issues by using tree-ring data from spruce (Picea abies) and cembran pine (Pinus cembra) trees growing in the central eastern Alps. Cores from living trees were taken at 24 altitudinal transects (between ca. 1300 and 2100 m a.s.l.) with different aspects in four areas (Durlaßboden, Schönnachtal, Schlegeisspeicher, Zembachtal) in the Zillertal Alps north of the main Alpine ridge. Just few cored spruce trees are located above ca. 1800 m a.s.l. while most cembran pine trees were sampled above that altitude. Usually two cores per tree were taken. Earlywood and latewood widths (EWW, LWW) were measured separately and tree-ring widths (TRW) were calculated resulting in 872 and 497 series for spruce and cembran pine, respectively, for these parameters. The chronologies established run back from 2011 to 1722 (spruce) and 1674 (cembran pine). The analyses presented focus on the TRW and LWW data. TRW chronologies display high similarities with other Alpine chronologies of the same species. LWW chronologies show high correlations with Alpine maximum density chronologies. To investigate altitude and aspect related effects on growth tree-age effects were removed by applying single regional growth curves constructed with the established data sets. The results show a nearly linear decline of TRW and LWW of spruce by roughly 10 to 12 % a 100 m increasing elevation whereas both TRW and LWW indicate maximum values around 1800 m a.s.l. and lower values around. No significant growth differences were found for both species after splitting the data sets into North- and South-group related to aspect. However, a further splitting of the data sets leads to a more complex picture. This could partly be caused by the smaller datasets that are potentially influenced by individual trees growing under very local conditions. This research has been supported by the Austrian Climate and Energy Fund (project ACRP4 ClimInterVal).


31

Cambial activity and wood formation in European beech (Fagus sylvatica L.) growing in the Czech Republic

K. Giagli1, V. Gryc1, H. Vavrčík1, L. Menšík2 1 Department of Wood Science, Faculty of Forestry and Wood Technology, Mendel University in Brno,

Zemědělska 3, 613 00, Brno, Czech Republic 2 Department of Landscape Management, Faculty of Forestry and Wood Technology, Mendel

University in Brno, Zemědělská 3, 61300 Brno, Czech Republic

European beech’s (Fagus sylvatica L.) longevity and adaptivity to various sites, places it among the most optimal European species for tree-ring studies. The objective of this paper is to analyse the process of wood formation on cellular basis, comparing seasonal cambium dynamics and differentiation phases, between 2010 and 2011 growing seasons, in European beech trees, and thereafter, to infer the influence of three climatic parameters dominating during growing period. Microcores (1.8 mm in diameter) were taken at weekly intervals (March to October) from six healthy trees growing in Rajec-Domanka site in the Czech Republic by using Trephor tool. Cross microsections were prepared according to standard procedure, stained in safranin and astra blue and monitored by using Leica DMLS microscope connected with Leica DFC 280 digital camera. Air temperature (1m above ground), soil temperature and soil moisture content (30cm below ground) were daily measured directly at the research plot. The cambial activity onset timing was found different between two growing seasons. Furthermore, an approximately 14 day’s timing shift of the wood formation phases occurred between 2010 and 2011. However, averaged air temperature was similar when onset eventually occurred (9.6 ± 1.6°C and 9.9 ± 4.0°C respectively), as well as during the beginning of each formation phase. A significant decrease of soil moisture content during 2011 growing season was recorded (13.0 ± 4% and 9.8 ± 3 % for 2010 and 2011 respectively), air temperature was found significantly different between two years (14.7 ± 5.6oC and 15.2 ± 5oC respectively), while soil temperature ranged alike (11.8 ± 2.2oC and 11.1 ± 2.1oC respectively. Acknowledgements: This research was created with support of the project CZ.1.07/2.3.00/30.0031, Postdoc contracts at MENDELU technical and economic research, with the financial contribution of EC and the state budget of the Czech Republic. European Social Fund and the state budget of the Czech Republic, Project Indicators of Trees Vitality Reg. No. CZ.1.07/2.3.00/20.0265.


32

Plastic and locally adapted phenology in cambial seasonality and xylem and phloem formation in Picea abies from temperate

environments J. Gričar1, P. Prislan1, V. Gryc2, H. Vavrčík2, M. de Luis3, K. Čufar4

1 Slovenian Forestry Institute, Ljubljana, Slovenia 2 Mendel University in Brno, Faculty of Forestry and Wood Technology, Brno, Czech Republic

3 University of Zaragoza, Dept. Geografía, Zaragoza, Spain 4 University of Ljubljana, Biotechnical Faculty, Dept. of Wood Science and Technology, Ljubljana,

Slovenia

How intra-annual radial growth of Picea abies (L.) H. Karst. is influenced by weather conditions in forest stands with a high production capacity has scarcely been explored. We analysed the sensitivity of P. abies to weather conditions, not at the limits of the species’ distribution but well within the temperature and precipitation ranges in which most spruce forests find their optimal growth conditions. Unlike most other studies, cambial cell production on both sides, xylem and phloem, was recorded in order fully to assess and compare its production capacities. Between 2009 and 2011, phenological variation in seasonal cambial cell production was analysed in adult Picea abies trees from three contrasting sites, two in Slovenia and one in the Czech Republic, differing in altitude and latitude. Each year, microcores were collected at weekly intervals from March until October. The tissues were fixed, embedded in paraffin, cut on a rotary microtome, and stained with safranine / astra blue water mixture. The cross-sections were examined with light microscope and image analysis system. The results indicate that the timing of cambial cell production is a highly synchronic process within populations since in all cases the cambium simultaneously started and stopped producing xylem and phloem cells. Our results also demonstrate that the phenology of cambial cell production is highly variable and plastic between years, depending on seasonal temperature and precipitation variation. Differences among sites, however, are only partially explained by different environmental (elevation and altitude) and climatic conditions, suggesting that local adaptation may also play a decisive part in the strategy of P. abies for adapting wood and phloem increments to function optimally in local conditions.


33

Differences in intra-annual wood formation in Norway spruce along the treeline ecotone, Giant Mountains, Czech Republic

V. Treml1, J. Kašpar1, H. Kuželová1, V. Gryc2 1 Department of Physical Geography and Geoecology, Faculty of Science, Charles University in

Prague, Prague, Czechia 2 Department of Wood Science, Faculty of Forestry and Wood Technology, Mendel University in

Brno, Brno, Czechia

Elevation-related decrease in growing season temperatures is a highly important factor in limiting tree growth in cold environments such as alpine treeline ecotones. In this study, we aimed to identify in Norway spruce radial growth timing differences between the lower (timberline) and upper (treeline) parts of an alpine treeline ecotone. Over three growing seasons, soil and air temperatures were measured and phenology of wood formation was analyzed at two sites separated by 140 m of elevation in the Giant Mountains, Czech Republic. The results showed that the most pronounced between-site differences in numbers of cambial and enlarging cells occurred during the early part of the growing season, with timberline trees having more of both of these kinds of cells. During the second part of the growing season, a period with significantly higher numbers of enlarging and wall-thickening cells at timberline than at treeline was detected. Thus, higher ambient temperatures at timberline than treeline led to higher numbers of cambial and enlarging cells, requiring longer time for their maturation. However, significant delay in the beginning of wood formation at treeline in comparison to timberline was observed only in 2011, when soil was frozen markedly longer at treeline. We found that cambial activity significantly increased when soil temperature increased from near-zero to a threshold temperature of 4-5 °C. We therefore suggest that for Norway spruce both the above- and belowground parts of the tree must be sufficiently warm for full resumption of cambial activity.


34

Intra-annual dynamics of cambial phenology and radial growth reveal that species-specific climate-growth relationships are not related to

different timing of maximum radial growth

W. Oberhuber, R. Schuster, I. Swidrak Institute of Botany, Leopold-Franzens-University of Innsbruck, Innsbruck, Austria

Previous dendroclimatological studies in a dry inner Alpine environment (750 m asl, Tyrol, Austria), where drought periods frequently occur at the start of the growing season in spring, revealed different growth response of co-occurring mature coniferous species (Pinus sylvestris, Larix decidua and Picea abies) to climate, which was suggested to be caused by a temporal shift in wood formation among species (Schuster and Oberhuber, 2013). To clarify this assumption, we determined key phenological dates of xylem and phloem formation by repeated micro-sampling of the stem and continuously monitored intra-annual dynamics of radial stem growth by band dendrometers during two consecutive years. Climate during study years in 2011 and 2012 distinctly deviated at the start of the growing season in spring. Mean daily air temperature in April 2011 was 3.2 °C higher compared to 2012 and an almost continuous drought period lasted from late March to early May 2011. Xylem formation in P. sylvestris started in mid and late April 2011 and 2012, respectively and in both years about 2 wk later in P. abies and L. decidua. Phloem formation preceded xylem formation on average by 3 wk in P. sylvestris, and c. 5 wk in P. abies and L. decidua. While a shift in temporal dynamics of radial growth onset and cessation was detected among co-occurring species, high synchronicity was found in culmination of radial growth in all species and in both study years (late-May 2011 and early June 2012). Correlations between radial stem increments extracted from dendrometer traces and environmental variables revealed that moist atmospheric conditions during the main growing period significantly favoured radial growth in all species. Therefore, variability in xylem increment among years and species is related to exogenous control by climatic factors and species-specific sensitivity to drought, respectively. On the other hand, production of phloem cells was quite homogenous and showed asymptotic decrease with respect to xylem cells indicating endogenous control. Results indicate that onset and culmination of xylem and phloem formation is controlled by early spring temperature, whereby strikingly advanced production of phloem compared to xylem cells suggests lower temperature requirement for initiation of the former and might be related to necessity of carbon transport at the start of the growing season. Because a temporal shift in timing of maximum radial could not be detected among selected conifers, we conclude that species-specific climate-growth relationships are due to (i) different strategies of water status regulation, i.e., anisohydric vs. isohydric behavior, and/or (ii) differences in water uptake efficiency.

REFERENCES

Schuster, R. & Oberhuber, W. (2013). Drought sensitivity of three-co-occurring conifers within a dry inner Alpine environment. Trees 27: 61-69.


35

Stem radial variation of maritime pine in a drought-prone environment: daily and seasonal pattern

J. Vieira1, S. Rossi2, F. Campelo1, H. Freitas1, C. Nabais1 1 MedDendro Lab., Centre for Functional Ecology, Department of Life Sciences, University of

Coimbra, Coimbra, Portugal 2 Départment des Sciences Foundamentales, University of Quebec in Chicoutimi, Chicoutimi, Canada

The variation in stem size of trees results from an irreversible component due to growth and a reversible component due to changes in the water balance of tissues. Thus, high-resolution measurements of stem radius can provide valuable information on the growth process as well as on the tree water status. This study investigates the hourly variations in stem radial increment of maritime pine (Pinus pinaster Ait.) using automatic band dendrometers. We tested the hypotheses that 1) stem radius variation has a daily and seasonal pattern that reflects the availability of water and 2) that once the internal water storage is depleted the tree enters a quiescent state. Stem radius variations were monitored during 2010 in four similar trees growing in the west coast of Portugal under a typical Mediterranean climate, characterized by a pronounced summer drought. The time series obtained from each tree were divided in three phases: contraction, recovery and radial increment. Amplitude and duration of each phase were calculated for each cycle and correlated with precipitation, maximum and minimum temperature. Five periods of physiological activity were defined according to the amplitude of the cycles and net radius variation: winter dormancy, spring growth, pre-summer contraction, summer quiescence and autumn re-hydration. Tree water deficit was extracted from the stem radial variation using a de-trending approach. A continuous positive radial increment started in spring and reached its maximum by the end of June. In July, a marked contraction was observed, when the highest temperatures and day length were recorded, with amplitudes of contraction and recovery 10 times higher than in the rest of the year. The maximum water deficit was observed in summer (pre-summer contraction and summer quiescence phases). The inability of trees to recover from the water lost in transpiration, and the reduction of internal water storage, were responsible for stem shrinkage and physiological quiescence observed during summer. Autumn precipitation triggered a rapid re-hydration and radial expansion with the return of trees to a physiologically active state. The relationship between duration and amplitude of the stem radial variation phases changed during the year and reflected the prevailing climatic conditions of each period. Daily variations in stem radius of maritime pine were mainly determined by the course of transpiration and thus dependent on temperature and tree water status.


36

Spatio-temporal dynamics of non-structural carbohydrates (NSC) and radial rays in the stem sapwood of Pinus sylvestris to drought and

long-term irrigation

G. von Arx1, A. Arzac2, P. Fonti1, D. Frank1, R. Zweifel1, A. Gessler1, L. Galiano1, A. Rigling1, J.M. Olano3

1 Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland 2 Universidad del País Vasco, Barrio Sarriena s/n, Leioa, Spain

3 Universidad de Valladolid, Los Pajaritos s/n, Soria, Spain

Combining dendroecological and tree physiological techniques, we quantified NSC, radial rays and ring width in the stems of 20 mature Pinus sylvestris trees growing in the naturally dry Swiss Rhone valley (control) and compared the pattern to those in 20 other mature individuals subject to 10 years of irrigation. There was no relationship between the concentration of NSC and the proportion of radial rays in the xylem, which means the amount of radial rays does not limit NSC storage. The proportion of rays did also not respond to the irrigation treatment as did ring width, although there was a diverging trend between control and irrigated trees in the last few years. The concentration of NSC decreased with increasing ring width, but the absolute NSC content in wider rings was still larger because of the additional tissue. This suggests that trees allocated proportionally more photoassimilates to storage than to growth under poor conditions. The absolute NSC content determined ring width in the next year, even when controlling for the previous years’ growth. However, this relationship was only observed in the irrigated trees, where cambial division was probably less limited. These results will be discussed in the context of carbon sink vs. source limitation and active vs. passive carbon storage.


37

Growing is not putting on weight! New insights into intra-annual dynamics of carbon sequestration in

trees

C.B.K. Rathgeber, H.E. Cuny INRA, UMR 1092 LERFOB, F-54280 Champenoux, France

Growth in size is highly correlated with the accumulation of biomass for a wide range of organisms. Wood currently stores more than 90% of the living biomass on earth and fixes nearly half of the carbon assimilated annually through photosynthesis. However, the functional link between tree radial growth and carbon sequestration in wood remains unexamined at the intra-annual time step at which these processes are simulated in state-of-the-art land surface models. Here, we show that radial growth and carbon sequestration in trees are largely delayed during the season. The phasing of radial growth closely matches the seasonal course of the photoperiod, whereas the carbon sequestration in wood follows the temperatures. The carbon sequestration offset has important implications for the sensitivity of these processes to environmental variations. Our study challenges widely applied definitions of growth, provides new insights into the timing and mechanisms of terrestrial carbon storage, and raises important questions on future climate-carbon interactions.


38

Long cell chronologies shed new light on Norway spruce response to climate

D. Castagneri, G. Petit, M. Carrer Dept. TeSAF, University of Padua, Legnaro (PD), Italy

Quantitative wood anatomy, i.e. the analysis of wood cell features in tree rings, has been considerably expanded over the last years. While most studies have been conducted on broadleaves, due to their relatively large and thus easy to measure water-conducting vessels, now is emerging an increased interest in conifers. Due to complex and time demanding procedures, most studies used relatively few cell radial rows for each tree ring, and few rings for each increment core, limiting the study time span to few decades. However, recently developed software and improved laboratory techniques allow to overcome most of the former limitations. The aim of our research was to investigate how climate affects Norway spruce cell chronologies, thus providing a better understanding of spruce xylem adjustment to climate warming. Increment cores from 24 trees were collected in three sites at 1200, 1600 and 2100 m a.s.l. at Croda da Lago, Eastern Italian Alps. Thin sections were prepared with a rotary microtome, stained with safranin and observed under the microscope at 40X magnifications. Images of cross sections were processed with Roxas software. This allowed to calculate anatomical parameters based on cell lumen area from hundreds to thousands of cells per ring. Cell series spanned 130 to 350 years, thus, due to the (age-) size related trend, the series were detrended. Using daily records of temperature and precipitations from a nearby weather station, climate-growth relationships were assessed over 85 years. Winter precipitation (snow) positively affected both cell size and number in all the sites. On the other hand, summer climate had a much more complex effect on spruce xylem features. At high elevation, cell number was positively affected by high summer temperature. June temperature positively affected even cell lumen size, but early May and late July temperature had a moderate negative effect. On the opposite, at intermediate and low elevation, cell size mainly depended on the water supply during early summer. Quantitative wood anatomy in conifers can increase our understanding of climate effects on trees, showing aspects not noticeable with ring width analysis, such as the observed complex influence of summer temperature on spruce xylem at the altitude forest limit, and the importance of early summer precipitation on cell size at intermediate elevations.


39

Blue Reflectance – new dendrochronological tool

R.J. Kaczka, B. Czajka Faculty of Earth Science, University of Silesia, Sosnowiec, Poland

One of the recent inventions of proxies related to tree-ring is the use of the image analyses of blue spectrum reflected from wood, known as Blue Reflectance (BR) or Blue Intensity. Here we present the analyses of the blue reflectance for six coniferous spices which grow in Tatra Mountains, Carpathians within subalpine (Larix decidua Mill., Picea abies (L.) Karst., Pinus Cembra (L.), Pinus mugo Turra) and montane (Abies alba (L.) Karst., Pinus sylvestris (L.)) zones, complete set of coniferous spices grow in Tatras and entire Carpathians. We aimed at: i) testing the potential of BR as climate proxy, ii) comparing BR to tree-ring width (TRW) maximum wood density (MXD) records, iii) testing the use of the new proxy for dating of historical wood. Growth response to climate analysis of the BR and TRW chronologies shows respectively rather consistent response to current-year spring-summer (April - August) and high summer (June - July) temperature (calculated for 1901 - 2006 period). The BR chronologies of all species show the higher response to climate than TRW and comparable, considering the values and periods, with MXD. The established chronologies were successfully employed to date the historical wood and other dendrochronological tasks. The study were supported by the National Science Centre, project no 2013/11/B/ST10/04764.


40

The ecology of inhomogeneous variance in tree-ring widths

C. Zang1, I. Dorado Liñán1, D. Frank2, E. Gutiérrez3, A. Menzel1,4 1 Technische Universität München, Chair of Ecoclimatology, Freising, Germany

2 Swiss Federal Research Institute WSL, Birmensdorf, Switzerland 3 Universitat de Barcelona, Department d’Ecologia, Barcelona, Spain

4 Technische Universität München, Institute for Advanced Study, Garching, Germany

The inhomogeneity of variance in tree-ring width is a wide-spread phenomenon, and dendrochronologists have developed a family of tools to transform time-series of tree-growth into stationary time-series (i.e., having constant mean and variance over time) suitable for statistical analysis. In this study, we do not consider heteroscedasticity as a confounding effect for analyzing tree-ring data. We rather take a closer look at the drivers of instable variance in tree-growth and illustrate the potential of exploring patterns of heteroscedasticity for ecological questions. We exemplify our approach with two story lines: the recent climate-induced increase in variability in Pinus spp. growth in the Pyrenees (Andreu et al. 2007) and the growth decline and recovery of Abies alba in Southern Germany, predominantly controlled by spatio-temporal patterns in airborne pollutants (Elling et al. 2009). Using original raw data from these studies and a combination of dendroclimatological calibration and forward modeling of ring width, we aim to disentangle climatic drivers and other exogeneous influences on the variance structure of series of tree-ring widths.

Our findings indicate that the heteroscedasticity of the modeled ring-widths mostly reflects the temporal development of the macroclimatic drivers, whereas the heteroscedasticity of the observed data shows more complex, sometimes even opposing patterns, and is not exclusively explained by climatic drivers. Similarly marked differences between modeled and observed data are also found for the temporal development of sensitivity of tree-growth.

Furthermore, we demonstrate how standard data treatment in dendrochronology might mask interesting exogenous effects and impede their ecological importance and interpretation, and explore alternative techniques such as ARCH and GARCH for practical non-stationary tree-growth modeling.

REFERENCES

Andreu, L. et al. (2007). Climate increases regional tree-growth variability in Iberian pine forests. Global Change Biology 13: 804-815. Elling, W. et al. (2009). Dendroecological assessment of the complex causes of decline and recovery of the growth of silver fir (Abies alba Mill.) in Southern Germany. Forest Ecology and Management 257: 1175-1187.


41

ROXAS – a powerful image analysis tool for tree-ring anatomy

G. von Arx Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland

Tree-ring anatomical features such as conduit size, density, cell wall thickness and ray abundance are nowadays recognized as valuable archives of past growth conditions. Compared to ring width that integrates conditions over an entire growing season, tree-ring anatomy, i.e. the analysis of anatomical features in time series of decades to centuries, can provide information about past growth conditions in an intra-annual resolution. Despite these promising perspectives, the wide use of tree-ring anatomy has been mostly limited by technical constraints, because measuring anatomical features is often very cumbersome and time consuming. This is why time series of wood anatomical features have been either short or based on a small subset of the sample such as a few radial files. In this talk I will present ROXAS: a specialized image analysis tool that has been developed to overcome many of the constraints (von Arx & Dietz, 2005). ROXAS can be used for diffuse (Wegner et al., 2013) and ring-porous (Fonti et al., 2009) angiosperms, and for conifers (von Arx & Carrer, 2014), for (circular) branches and roots as well as (linear) tree cores. It is designed to process large images of large samples and produce output for all conduits, even in conifers (up to 1,000,000 tracheids per sample). After automatic recognition of conduits and (with some limitations) ring borders, the user can efficiently improve the automatic output directly in the image. Besides the lumen area and position of conduits and ring width, the final data output includes, many additional parameters such as size distributions of conduits, mean hydraulic diameter, absolute and relative position within the ring, theoretical hydraulic conductivity, different measures of conduit grouping (angiosperms; von Arx et al., 2013) and – very recently – cell wall thickness for all conduits (conifers). The focus of this talk will be laid on some illustrative examples for the more advanced options of ROXAS such as vessel grouping patterns and intra-annual density profiles based on lumen area and cell wall thickness of all tracheids.

REFERENCES

Fonti, P., Eilmann. B., García-González, I. & von Arx, G. (2009). Expeditious building of ring-porous earlywood vessel chronologies without loosing signal information. Trees-Structure and Function 23: 665-671. von Arx, G. & Carrer, M. (2014). ROXAS - a new tool to build centuries-long tracheid-lumen chronologies in conifers. Dendrochronologia. http://dx.doi.org/10.1016/j.dendro.2013.12.001 von Arx, G. & Dietz, H. (2005). Automated image analysis of annual rings in the roots of perennial forbs. International Journal of Plant Sciences 166: 723-732. von Arx, G., Kueffer, C. & Fonti, P.(2013). Quantifying vessel grouping – added value from the image analysis tool ROXAS. IAWA Journal 34: 433-445. Wegner, L., von Arx, G., Sass-Klaassen, U. & Eilmann, B. (2013). ROXAS – an efficient and accurate tool to detect vessels in diffuse-porous species. IAWA Journal 34: 425-432.


42

Disentangling the effects of competition, climate and CO2 concentrations on tree growth and water use efficiency

L. Fernández-de Uña1, N.G. McDowell2, I. Cañellas1, G. Gea-Izquierdo1,3 1 INIA - CIFOR, Madrid, Spain

2 Los Alamos National Laboratory, Los Alamos (NM), USA 3 CEREGE - CNRS/Aix-Marseille Université, Aix-en-Provence, France

In the Mediterranean region, climate change scenarios forecast rising temperatures and stable or even decreasing precipitations, increasing the frequency and intensity of drought events (IPCC, 2007). Climate change long-term effects can be, however, modulated by other environmental factors, such as CO2 fertilization or stand competition. Due to the different synergistic and opposing effects that different environmental variables can exert on tree physiology, it is important to determine how species will respond to changing environmental conditions. This study aims to assess the effect of competition, climate and CO2 on the growth and intrinsic water use efficiency of three different species found in Mediterranean mountains: Quercus faginea Lam., Quercus pyrenaica Willd. and Pinus sylvestris L. We used basal area increment (BAI) and tree-ring carbon isotope content (δ13C) data from low- and high-density plots subjected to thinning located in five even-aged, monospecific stands found along the Spanish Iberian and Central Systems. δ13C values were used to estimate intrinsic water use efficiency (iWUE). BAI increased immediately after thinning and remained significantly higher in low-density than in high-density plots. Conversely, no significant differences between competition levels were found in iWUE for any of the three species, not even on the driest years. In the long term, there was a significant increasing trend in iWUE for all species and sites, which did not result in an increase in growth rates. The ratios between the CO2 concentration in the plant and atmospheric CO2 concentration (ci/ca) indicate that this increase in iWUE was induced by rising CO2 concentrations in P. sylvestris, whereas in Quercus spp. it could also have been caused by stomatal closure due to increasing temperatures, and consequently, increasing evapotranspiration rates and drought stress. This contrasts with the isohydric character of Pinus spp., which prevent xylem cavitation through early stomatal closure, and the anisohydric character of Quercus spp. Our results indicate that, as suggested for other Mediterranean forests (Peñuelas et al., 2008), increasing water use efficiency as a result of increasing CO2 concentrations has not been sufficient to compensate the detrimental effect of increasingly drier conditions on tree growth in recent decades. Reduced competition may, however, minimize the negative growth response to warmer conditions.

REFERENCES

IPCC (2007) Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K.B., Tignor M., Miller H.L. (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 996 pp. Peñuelas J., Hunt J., Ogaya R., Jump A. (2008) Twentieth century changes of tree-ring δ13C at the southern range-edge of Fagus sylvatica: increasing water-use efficiency does not avoid the growth decline induced by warming at low altitudes. Global Change Biology 14: 1076-1088.


43

Determination of erosion rates through the use of dendrogeomorphology

R.C. Bovi1, M. Cooper1, M. Tomazello Filho1, M. Peres Chagas1, R. Santos Momoli2, V. Dominguez Castillo1

1 University of São Paulo, Piracicaba, Brazil 2Federal University of Goías, Goiânia, Brazil

Erosive events can expose roots and record evidences of these events. Dendrogeomorphology has been used as a reliable tool for dating erosive events and calculation of erosion rates in temperate regions, however, this kind of research is still scarce in tropical regions. This study was conducted on Schizolobium parahyba trees, in an Atlantic Forest fragment, in São Paulo, Brazil. The area is characterized by innumerous gullies exposing roots, that allows to calculate erosion rates in different positions of the landscape. Erosion rates were inferred by scars found in exposed roots, caused by impacts of sediment and debris. These scars are evidences of root exposure to erosion processes since they weren’t found in buried roots. Erosion rates of the area were calculated through dating the oldest root exposed and the distance between this root and soil surface. For calibration and validation of the chronology of erosion processes, the dating of the growth rings were statistically conferred by COFECHA. The method is presented as a precise tool for geochronological dating of erosive events in tropical regions.


44

Reactions of oak (Quercus robur L.) to a sudden peatland rewetting – implications for bog-oak research?

T. Scharnweber1, J. Couwenberg1, I. Heinrich2, M. Wilmking1 1 Ernst-Moritz Arndt University-Greifswald, Institute of Botany and Landscape Ecology,

Soldmannstr.15, 17489 Greifswald, Germany 2 Climate Dynamics and Landscape Evolution, GFZ-German Research Centre for Geosciences,

Telegrafenberg, 14473 Potsdam, Germany

Soil-waterlogging with the subsequent anoxic soil conditions is besides drought one of the major stress factors for trees. Increasing frequencies and intensities of heavy rainfall events as well as an increase in winter precipitation as projected for northern Central-Europe might therefore have a severe impact on forest growth at hydric sites. Although pedunculate oak (Quercus robur L.) shows a distinct tolerance to waterlogged soil conditions, even this species might suffer from increasing wetness. Therefore a careful evaluation of its growth reactions and adaptive capacity is needed to assess possible impacts of changing climatic conditions. In addition, a detailed analysis of its growth patterns in response to increasing soil waterlogging may facilitate a more comprehensive calibration of growth patterns found in subfossil bog-oak material, an important climate proxy of the Holocene. The Anklamer Stadtbruch, a partly forested peatland at the Baltic seashore has been intensively drained for several decades but was occasionally flooded. In November 1995 a severe storm-flood permanently damaged the dam. As a consequence, water tables near or above the surface led to area-wide forest dieback. Only at somewhat higher areas some of the trees, mostly oaks, survived. This well-defined disturbance event of a sudden hydrological shift offers the unique possibility to study the influence of increasing soil (peat) waterlogging on oak growth. For our dendroecological study we sampled tree cores from three groups of apparently vital, damaged and dead oaks. Conventional tree-ring analysis (early/latewood width) was combined with cell-anatomy of earlywood vessels. Ring data was contrasted against instrumental climate and gauging data. Results show an influence of micro-site conditions along with a higher chance for smaller and suppressed trees to survive the increasing soil (peat) waterlogging. Vital trees display a typical ring-pattern with four to five years of depressed growth and a subsequent recovery, characterised by a significant increase in ring-width, especially in the earlywood (width and vessel-lumen). Interestingly, a similar growth increase could be observed in reaction to the opposite hydrological change, the intensified drainage after dam construction in 1934. Dead and damaged trees typically show strongly reduced latewood-width and die-off gradually. Water level proved to be the overriding factor influencing oak growth at our site, already during times of intensive drainage. We discuss our findings with regard to the interpretation of subfossil bog oak material and propose a modified version of release detection analysis as a tool to sharpen the identification of hydrological shifts in bog-oak material.


45

Using tree-ring based reconstruction of stand structure to assess tree growth variation in high-latitude boreal forests

T. Aakala, F. Berninger, M. Starr Department of Forest Sciences, University of Helsinki, Finland

Understanding variation in tree growth is a key to understanding forest dynamics in changing environmental conditions. There are several, well documented sources of variation that influence growth, such as size of the tree, competition and climate, and their interactions. Variation in tree growth is typically assessed over multiple years, as a function of characteristics of the focal tree and its neighborhood, or as a function of climate at an interannual scale. Studies in which characteristics of the focal tree, its neighborhood and climate are considered simultaneously at an annual resolution are few. Combining stem-mapped and tree ring data, we reconstructed stand development in 48 stands of naturally dynamic old-growth forests in northern Finland, to obtain data on tree and neighborhood conditions at annual resolution over several decades. Using this reconstruction and mixed effects modeling, we asked (1) which factors influence growth at annual scales (characteristics of the trees themselves, their neighborhood, or site) and (2) if these characteristics influence the response of tree growth to climate. Here, we report first results of this work.


46

Spatial variability in growth – climate relationships of red pine in Ontario, Canada

M. Waseem Ashiq, M. Anand University of Guelph, Guelph, Canada

Climate is considered to be one of the main factors influencing forest dynamics through its influence on various physiological and phonological processes (Kramer et al., 2002). Changes in climate can potentially influence the distribution, abundance and assemblage of species by affecting their birth, growth, death and dispersal rates (Hansen and Rotella, 1999). Investigating growth – climate relationships can potentially help us in better understanding forest dynamics particularly under changing climate (Cook and Cole, 1991). Tree ring studies are quite helpful in exploring these relationships over longer periods (Fritts, 1976). Studies show that radial growth in species is influenced by climate and can provide insight about growth – climate relationships (Miyamoto et al., 2010). In eastern North America red pine (Pinus resinosa Ait) is a major conifer species in Great Lake – St. Lawrence forests. This species has sufficient dendroclimatic potential and has been used in combination with other species for various regional analyses. However, no attempt has been made to assess its broad scale associations with seasonal climate and the spatial variability of these associations in Northern Ontario. This study was carried (i) to identify key climatic variables influencing red pine growth in Northern Ontario, Canada and (ii) to compare and contrast the spatial patterns of these climate – growth relations in various ecoregions. We used tree ring data from a large network of sampling sites to perform growth – climate analyses for 20th century. Our results show that climate (precipitation and maximum temperature) during preceding year’s summer mainly influences the growth of red pine. Combination of positive response to precipitation and negative response to temperature during summer seasons indicates that this species is vulnerable to moisture stress. This has implications for its management as drought frequency is reportedly increasing in this area. We also find spatial variability of climate – growth relationships at ecoregion to sub-ecoregion level. This study provides important information to develop strategies for managing complex forests.

REFERENCES

Cook, E.R. & Cole, J. (1991). On predicting the response of forests in eastern North America to future climatic change. Climate Change, 19: 271–282. Fritts, H.C. (1976). Tree rings and climate. New York: Academic Press Inc. Hansen, A.J. & Rotella, J.J. (1999). Environmental gradients and biodiversity. In M. Hunter (Ed.), Managing Forests for Biodiversity (pp 161–209). Cambridge (UK): Cambridge University Press. Kramer, K. et al. (2000). The importance of phenology for the evaluation of impact of climate change on growth of boreal, temperate and Mediterranean forests ecosystems: an overview. International Journal of Biometeorology, 44(2): 67–75. Miyamoto, Y. et al. (2010). Growth responses of three coexisting conifer species to climate across wide geographic and climate ranges in Yukon and British Columbia. Forest Ecology & Management, 259: 514-523.


47

Female trees can grow and store more than males under favourable environments

L. DeSoto1, J.M. Olano2,V. Rozas3 1 Centro de Ecologia Funcional, Universidade de Coimbra, Coimbra, Portugal

2 Área de Botánica, EUI Agrarias, Universidad de Valladolid, Soria, Spain. 3 Laboratorio de Dendrocronología, Facultad de Ciencias Forestales, Universidad Austral de Chile,

Chile.

Sexual dimorphism in dioecious plants can be evidenced by contrasting growth and resource storage patterns, although both traits have been rarely studied together. In this study, we aim to assess the long-term radial growth and the seasonal variation of non-structural carbohydrates (NSC) content in sapwood of the dioecious tree Spanish juniper (Juniperus thurifera L.) in north-central Spain. We randomly selected 20 individuals per sex at two sites with contrasting environmental conditions: a wetter north-aspect slope and a drier plateau. Earlywood and latewood ring-width chronologies were built per site and sex for the period 1931-2010. Sapwood cores were collected bimonthly from June 2006 to June 2007, and the content of NSC was quantified into two separately fractions, soluble sugars (SS) and non-soluble sugars (NSS). Our main finding was that sex-specific differences in secondary growth and NSC stem contents were modulated by environmental conditions. Juniper females showed wider earlywood growth and stored more NSS than males on the wet north-aspect slope, while there were not differences between the sexes in the dry plateau. We also found a relationship between secondary growth and NSC levels in females, suggesting that the amount of carbon reserves of female trees, but not of males, could be favoured by previous growth. Sex-specific differences in growth and NSC storage are context dependent. This is likely because photosynthetic rates and resource uptake are modulated by hydraulic conductivity, particularly in the less efficient water-use female trees.


48

Climate effect to larch growth on abandoned oil shale quarries in Sirgala (Estonia)

M. Hordo, E. Dubolazov, L. Krumm, A. Kiviste Department of Forest Management, Estonian University of Life Sciences, Tartu, Estonia

Since 1960, for intention of restoration has planted larch on abandoned oil shale quarries. Trees respond to environmental factors with similar changes in growth increment, records of past influence are retained in tree-rings and can be detected through dendroecological techniques. The aims of study were to analyze climate-growth relations in larch stand and tree growth trends. Increment cores were collected on abandoned oil shale quarries from research sample sites in summer 2013. Sample sites were divided into three groups: Larix decidua, L. kaempferi and mixed Larix sites. Tree-ring width, early- and latewood were measured with LINTAB system with accuracy 1/100 mm. Climate (monthly temperature Tavg, Tmin, Tmax and precipitation) data from closest weather station Kunda were used. T-test (to compare mean growth between groups), correlation analysis (to analyze relationships between radial growth and climate), principal component analysis and pointer year analysis (to detect extreme growing years) and superposed epoch analysis (to analyze disturbances) were used. Positive correlation was detected between increment indices and temperature in the October and November of previous year, also during vegetation period (from May till August). As well, annual precipitation had positive correlation with radial growth of larch trees. Radial growth of larch was limited by mean monthly temperature in February, in previous year July and August. Also minimum temperature has negative effect in June, July and August to radial growth. The earlywood of L. kaempferi was found positively correlated with precipitation from beginning of vegetation period. Significant positive correlation occurred between latewood on all three sites and annual precipitation and during vegetation period. Common positive pointer years were 1973 and 2008, and negative year was 2003. Results showed that L. decidua was growing better than trees on L. kaempferi and mixed Larix sites.


49

Climate reconstructions from tree-ring widths for the last 850 years and the need for new tree-ring proxies in northern Poland

I. Heinrich1, A. Knorr1, A. Bieber1, K.-U. Heußner², T. Ważny³, M. Slowinski1, G. Helle1, S. Simard1, T. Scharnweber4, A. Brauer1

1 GFZ German Research Centre for Geosciences, Potsdam, Germany ² German Archaeological Institute, Berlin, Germany

³ The University of Arizona, Tucson, USA 4 University of Greifswald, Greifswald, Germany

Tree-ring based temperature reconstructions form the scientific backbone of the current debate over global change, and they are the major part of the palaeo data base used for the IPCC report. However, long temperature reconstructions derived from temperate lowland trees growing well within their distributional limits in central Europe are not part of the IPCC report, which is an essential gap in the international data base. It appears that dendroclimatological analysis at temperate lowland sites was so far difficult to perform mainly for three reasons: diffuse climate-growth relationships, the lack of long chronologies due to absence of sufficient numbers of long-living trees and the potential loss of low-frequency signals due to the short length of the sample segments. We present two robust multi-centennial reconstructions of winter temperatures and summer precipitation based on pine and oak tree-ring widths chronologies from northern Poland, where so far no long tree-ring based reconstructions were available. We compared the new records with global, hemispherical and regional reconstructions, and found good agreement with some of them. In comparison, the winter temperature of our reconstruction, however, did not indicate any modern warming nor did the summer precipitation reconstruction suggest any modern 20th century changes. Then again, due to the short segment lengths of our individual series the resulting multi-centennial reconstructions suffered from the segment length curse inhibiting the preservation of low-frequency signals. Therefore, in a second step, we measured cell structures within the tree rings and developed chronologies of parameters such as cell wall thickness and cell lumen area for a period of several decades. We used our new method (Liang et al. 2013a,b) applying confocal laser scanning microscopy to increment core surfaces for efficient histometric analyses. We focused on samples covering the last century because meteorological data necessary for calibration studies were available for direct comparisons. It was demonstrated that the correlations with climate were strong and different from those found for tree-ring widths (e.g., N-Poland oak-vessel-lumen-area-chronology with previous September-to-December mean temperature r = 0,61 and N-Poland pine-tracheid-lumen-area-chronology with mean Feb-to-June temperature r = -0,66). Since the cell structure data did not contain age trends, there was no reason for detrending, thus we were able to use raw values. By using raw values low-frequency signals could be sustained in the chronologies. Currently, long chronologies of cell structure measurements are being developed to finally produce robust reconstructions for the temperate lowlands of Europe, which contain not only high- but also low-frequency climate information for the last Millennium.

REFERENCES

Liang, W., Heinrich, I., Helle, G., Dorado Liñán, I., Heinken, T. (2013a). Applying CLSM to increment core surfaces for histometric analyses: A novel advance in quantitative wood anatomy. Dendrochronologia 31: 140-145. Liang, W., Heinrich, I., Simard, S., Helle, G., Dorado Liñán, I., Heinken, T. (2013b). Climate signals derived from cell anatomy of Scots pine in NE Germany. Tree Physiology 33: 833-844.


50

Reviewing tree-ring based temperature reconstructions for the past millennium

J. Esper1, P.J. Krusic2, F.C. Ljungqvist3, M. Carrer4, J. Luterbacher5, R.J.S. Wilson6, U. Büntgen7

1 Department of Geography, Johannes Gutenberg University, Mainz, Germany 2 Department of Physical Geography and Quaternary Geology, Stockholm University, 10691

Stockholm, Sweden1 3 Department of History, Stockholm University, 10691 Stockholm, Sweden

4 Università degli Studi di Padova – Dip. TeSAF – Treeline Ecology Research Unit - Agripolis, I-35020 Legnaro (PD), Italy

5 Department of Geography, Climatology, Climate Dynamics and Climate Change, Justus-Liebig University, 35390 Giessen, Germany

6 School of Geography and Geosciences, University of St Andrews, St Andrews, Scotland, UK 7 Swiss Federal Research Institute WSL, 8903 Birmensdorf, Switzerland

Millennial-length tree-ring chronologies form the backbone of high-resolution Northern Hemisphere temperature reconstructions (Frank et al. 2010). However, the considered use of these chronologies is challenging, particularly for non-dendrochronologists desiring to combine them with evidence from other archives into multi-proxy based reconstructions. Here we provide an overview of the extant 1000-year-long chronologies used for temperature reconstruction, and detail criteria supporting their evaluation including (a) homogeneity, (b) replication, (c) coherence, (d) chronology, and (e) signal. The calculation and combination of these criteria are briefly described using a databank of millennial scale tree-ring records, currently in development. The ultimate aim of this project is to develop a website listing all tree-ring based 1000-year-long temperature reconstructions, accompanied by a set of simple criteria evaluating the strengths and weaknesses of these records. The list might provide an aid for non-dendrochronologists, as well as dendrochronologists, wishing to use tree-ring data in large-scale climate reconstructions.

REFERENCES

Frank, D., Esper, J., Zorita, E., Wilson, R.J.S. (2010). A noodle, hockey stick, and spaghetti plate: a perspective on high-resolution paleoclimatology. Wiley Interdisciplinary Reviews on Climate Change 1: 507-516.


51

The tree growth to changing climate and drought conditions in East Denmark

W. Huang, J.B. Larsen, A. Ræbild, L. Thygesen, J.K. Hansen Department of Geosciences and Natural Resource Management, University of Copenhagen,

Copenhagen, Denmark

In view of the expected climate change, a higher frequency of summer droughts, heat waves and warmer winters will probably reduce the growth of forest tree in Denmark. Longer growing seasons might, however, increase for the growth of the species. This study aimed at studying the general response of a number of commonly planted tree species in Denmark, in terms of growth and formation of latewood to climate as well as the response during- and after severe drought spells of the different species. The objective was thus to predict how climate change might influence the growth and survival of the species in the future. The effect of climate on annual radial growth from approximately 1970 to 2012 was analyzed in eight different species from one typical sandy-clay site in Eastern Denmark , which was established in the autumn 1964 and the spring 1965 with Abies alba Mill., Picea sitchensis (Bong.) Carr., Abies grandis Lindl., Pseudotsuga menziesii L., Quercus robur L., Larix kaempferi Sarg., Fagus sylvatica L., Picea abies (L.) Karst. Earlywood, latewood, and total ring width were measured and statistically related to monthly, or periodic drought indices (DI= precipitation-potential evapotranspiration) monthly temperatures or monthly temperature sums and it was investigated how the growth of the different species was affected during- and after drought spells. The response of the different species to changes in drought and temperature are discussed in the context of climate change and choice of tree species with high plasticity in adaptation to a changing climate.


52

Plasticity in the dendroclimatic signal of Pinus pinea in connection to climate variability within its distribution range

F. Natalini, J. Vázquez-Piqué, R. Alejano Departamento de Ciencias Agroforestales, Escuela Técnica Superior de Ingeniería,

Universidad de Huelva, 21819 Palos de La Frontera (Huelva), Spain

The heterogeneous response of species to climate variability across their geographical distribution range is the result of phenotypic plasticity, which can be defined as the range of phenotypes that a single genotype can express as a function of local environmental conditions. In the actual climate change context, phenotypic plasticity of plant species is crucial for their acclimation or adaptation to new climatic conditions. This study was aimed at contrasting the climate-growth relationships of stone pine (Pinus pinea L.) in coastal stands in Southwestern Spain and Central Italy to explore the heterogeneous response of this species to local climatic regimes. To this end, we established tree-ring (TR) earlywood (EW) and latewood (LW) chronologies for 7 sites in the province of Huelva (SW Spain) and for one site in Tarquinia (C Italy). Both studied regions feature Mediterranean climate. We used data from the closest meteorological stations (monthly sums of precipitations and monthly average temperatures) to characterize local climate and compute climate-growth correlations. Cross-dated TR, EW and LW width series of individual trees were standardized and averaged to attain mean site chronologies of TR, EW and LW indexes. A principal component analysis of the correlation matrix of the index chronologies from Huelva was performed. The two principal components (PC1 and PC2) were examined to identify the pattern of association of TR, EW and LW with each component. The eigenvectors were used as dependent variables and meteorological data as independent variables in correlation functions. For Tarquinia, the index chronologies were used in climate-growth correlation analysis. The PC1 in all sites from Huelva was positively related to the TR and EW indexes, while the PC2 was positively related with the LW indexes. The first component eigenvector was positively correlated with precipitation of the previous November and current February, March and April, and negatively correlated with temperatures of the current spring (Mar-May). The second component eigenvector was positively correlated with precipitation in winter (Dec, Jan) and current autumn (Sep-Nov) and negatively correlated with temperatures in the current July. In Tarquinia, the TR and EW index chronologies were positively related to precipitation in the previous November and current June, while the LW index chronology was related to the June, August and September precipitations. No significant correlation with temperatures was found in Tarquinia. The dendroclimatic signal in Huelva suggests that P. pinea in this region mostly depends on water availability in the months preceding summer and is significantly sensitive to the water stress induced by high temperatures in spring. The dendroclimatic signal in LW indicates a later phase of cambial activity in autumn. In contrast, P. pinea in Tarquinia is strongly influenced by precipitation in the beginning of summer, did not present any significant relationships with spring climate and LW is sensitive to precipitation also in late summer in this region. In Huelva the arid period generally lasts from May to September and drought events can also occur in April, while in Tarquinia aridity is normally limited between June and August. This study provides an insight into the plasticity of P. pinea in connection to climatic gradients, that could be decisive for the response of this species to climate change impacts across its geographical distribution range.


53

Solar-terrestrial relations of the paleoclimatic archives in the South Siberia (Altai Mountains, Russia)

D. Ovchinnikov1, A. Mordvinov2, I. Kalugin3, A. Darin3, V. Myglan4 1 Institute of Forest SB RAS, Krasnoyarsk, Russian Federation

2 Institute of Solar-Terrestrial Physics SB RAS, Irkutsk, Russian Federation 3 Institute of Geology and Mineralogy SB RAS, Novosibirsk, Russian Federation

4 Siberian Federal University, Krasnoyarsk, Russian Federation

Solar-terrestrial relations were examined using millennium-scale paleoclimatic data from the Central Asia mountain region. The paleoclimatic data were based on non-varved lake sediments of the lake Teletskoye and temperature-sensitive long tree-ring width chronologies from the Altai region (Altai Mountains, South Siberia, Russia) in the late Holocene (2000 years). Cores of the bottom sediments from the lake Teletskoe (Altai Mountains) were subjected to X-ray fluorescent analysis, a method based on synchrotron radiation (spatial resolution is 0.1 mm). A method of empirical mode decomposition (EMD-method) was used to analyze different paleoclimatic data and to extract low-frequency variability from all presented archives. Low-frequency signals (modes) are shown: ~ 60-, ~100-, ~ 200-, ~300-500- and ~1000-year cycles in the lake Teletskoye; ~ 25-33-, ~ 50-60-, ~100-200-, ~ 300- and ~1000-year cycles in tree-ring width chronologies. Changes of the tree-ring width chronology on the millennial time scale coincide with changes of the solar activity in the Holocene. Stable relationships between solar activity and climate characteristics were found on 100-200-year time scales (Glaysberg and Suess (de Vries) cycles). Solar-terrestrial relations analysis revealed dominant 200-year cycle in all presented paleoclimatic archives. The study was supported by the Russian Foundation for Basic Research (projects 13-05-00620, 13-05-00621) and the Presidium of the Siberian Branch of the Russian Academy of Sciences (Interdisciplinary Integration Project SB RAS № 34).


54

Detection of large volcanic events based on their climatic fingerprint in a hemispheric wood density network

L. Schneider1, F. Pretis2, J. Esper1, J.E. Smerdon3 1 Department of Geography, Johannes Gutenberg University, Mainz, Germany

2 Programme for Economic Modelling, Oxford Martin School, Oxford, UK 3 Lamont-Doherty Earth Observatory, Columbia University, Palisades (NY), US

Large tropical volcanic eruptions and their associated injection of sulphate aerosols into the stratosphere compose one of the key forcings of the earth’s climate on annual to decadal time scales. Historic evidence and model-simulations indicate synoptic perturbations and severe cooling on hemispheric to global scales with significant socio-economic impacts subsequent to major events (e.g. Oppenheimer 2003). General circulation models derive their volcanic forcing records from ash depositions in millennium-long, polar ice cores and simulate the radiative effect of sulphate aerosols during stratospheric conveyance. While models thus provide indirect estimates of surface cooling, tree-ring reconstructions assess the actual climatic response to volcanic eruptions more directly. In the course of the last millennium, years of eruptive activity can be studied using a large proxy network. In order to avoid cooling patterns that are temporally smoothed, however, precise dating of volcanic events is mandatory (Esper et al. 2013), but often not available for ice-core records (Baillie 2008). Documentary archives with better dating, in turn, capture only limited time-spans and lack entirely in sparsely populated regions. Here we address these limitations by presenting a high-resolution summer-temperature record that enables the independent detection of volcanic-induced cooling events on a hemispheric scale. Using a network of maximum latewood density chronologies and an indicator-saturation method (Doornik et al. 2013) for peak detection, we identify pulse-like forcing events based on subsequent cooling without any temporal predetermination. The applied algorithm allows the detection of structural breaks - individual outliers or predefined response functions of multiple years - in the long-term temperature reconstruction. Approximately a dozen volcanic events reveal significant climatic implications during the past millennium and the majority of dates can be related to sulphate-peaks if dating uncertainties in the ice-core records are considered. Superposed epoch analyses for tree-ring instead of ice-core derived dates improve the estimates for magnitude and duration of volcanic-induced cooling. Spatially limited sampling of the tree-ring reconstruction, however, requires a careful assessment of the estimated volcanic responses before they can be employed as a validation for the strength and character of volcanic forcings in climate simulations.

REFERENCES

Esper, J. et al. (2013). European summer temperature response to annually dated volcanic eruptions over the past nine centuries. Bulletin of Volcanology 75: 736. Doornik, J.A. et al. (2013). Step-indicator Saturation. Working paper. Oppenheimer, C. (2003). Climatic, environmental and human consequences of the largest known historic eruption: Tambora volcano (Indonesia) 1815. Progress in Physical Geography 27: 230-259.


55

Does tree-genetics help resolve the “divergence effect”?

M. Wilmking1, A. Buras1, M. Schnittler1, J. Lange1, K. Treydte2, P. Eusemann1 1 Institute for Botany and Landscape Ecology, University Greifswald, Germany

2 Swiss Federal Research Institute WSL, Dendroclimatology Group, Birmensdorf, Switzerland

The inability of several high latitude and high elevation tree ring width (TRW) chronologies to capture recent warming trends is a hotly debated topic in dendroclimatology. In this study, we tested whether the genetic set-up of trees influences the radial growth response of trees in a natural setting at northern and elevational treelines in Alaska. Treeline communities in Alaska are mainly mono-specific with Picea glauca as the dominant tree species. We established two elevational gradients from continuous forest to treeline and sampled every tree within a certain area resulting in over 800 samples. Samples were analyzed genetically, for radial growth and a subset is planned for density and stable C and O isotope measurements. Results for TRW-chronologies confirmed a wide spectrum of diverging growth responses to environmental and recent climatic drivers, partially influenced by shifts in the Pacific Decadal Oscillation. Parentage analysis showed short-distance dispersal and identified consecutive tree generations. Sexual and clonal reproduction occurred simultaneously, offering an exciting opportunity to test the variability of radial growth records in identical genetic setups. We will now use this unique dataset to include the analyses of density and isotope chronologies. So far, genetics does seem to play a role in the response of the trees to climatic drivers, but the importance of each driver (e.g. intraspecific competition, variations in site conditions, climate or genotype of a tree) varied over time and thus highlights the complex interplay between individual living organisms and their environment.


56

Common temperature signal in six proxies based on the growth of Scots pine from northern Fennoscandia

M. Lindholm1, M.G. Ogurtsov2, R. Jalkanen1 1 Metla, Rovaniemi Research Unit, PO Box 16, FI 96301 Rovaniemi, Finland;

2 A.F. Ioffe Physico-Technical Institute, St. Petersburg, Russia

Six chronologies based on the growth of Scots pine – three ring width, two density and one height growth – from the inland of northern Fennoscandia were built to separately enhance low, medium and higher frequencies in growth variability in 1000–2002. The series are all known temperature proxies. Several periodicities of growth were found in common in these data. Five of the low-frequency series have a significant oscillatory mode at 200–250 years of cycle length. Most series also have strong multidecadal scale variability, significant peaks at 33, 67 or 83–125 years. Reconstruction models for mean July and June–August as well as three longer period temperatures were built and compared using stringent verification statistics. We describe the main differences in model performance (R2=0.53–0.62) between individual proxies as well as their various averages depending on provenance and proxy type, length of target period and frequency range. A separate medium-frequency June–August temperature reconstruction is presented, which is closely similar in amplitude and duration to the last two cycles of the Atlantic Multidecadal Oscillation (AMO). The good synchrony between these two series is only hampered by a 10 years difference in timing. Recognizing a strong medium-frequency component in Fennoscandian climate proxies helps to explain part of the uncertainties in the 20th century trends, e.g. a multidecadal periodicity in the early part taking place along an overall centennial warming trend and thus integrating natural and external components.


57

The view from the lake across mountains, valleys and plains: Perspectives of dendroarchaeology in a cultural heritage context

O. Nelle 1 Landesamt für Denkmalpflege Baden-Württemberg im Regierungspräsidium Stuttgart,

Dendrochronologisches Labor, Hemmenhofen, Germany

The ring of a tree expresses the living conditions of the organism on a yearly basis (in temperate regions). Its growth is influenced by climate, competition and cooperation, but also the action of animals and humans. Together with its taxonomically individual wood anatomy, it serves as the basic information unit for chronologies, the climate of the past, geomorphological dynamics, reconstructions of woodland dynamics and settlement development. In this poster, perspectives of dendroarchaeology are developed from the viewpoint of the tree ring laboratory of the Landesamt für Denkmalpflege Baden-Württemberg, Germany, which works in a cultural heritage preservation context. Being built up in 1982 and led since then by André Billamboz, it will continue its work under the new direction of the author. In the past, main focus was on the tree ring investigations of lake dwelling settlements in the region of Lake Constance and Upper Swabia. In parallel, being the dendrolab for the whole Federal “Land” of Baden-Württemberg, it is the central “tree archaeology” unit, with its task of protecting and investigating the archaeological wood legacy of the Land. Future foci will tackle: (1) the continuation of the lake dwelling research, especially in the light of a huge wealth of data which can now be used for synthesis analysis of whole regions, being performed within a network of partners of neighbouring countries; (2) Celtic and Roman legacy, with the aim of using wood charcoal for dendroarchaeology where waterlogged wood is unavailable; (3) continue work on dendrotypology developed by A. Billamboz, by exporting it in a running project to Northern German medieval wood; (4) continue to improve chronologies especially of certain taxa like Alnus or Abies. Fir is found frequently in charcoal production sites. 14C-dating is not precise enough to date these monuments, which in the course of Lidar-based monument inventarisation, became the most numerous monument in Baden-Württemberg. Thus dendrochronology is the most promising approach when timing this hitherto important woodland usage. It is the aim of future work to manage the preservation and investigation of the complete wood use legacy. Only the combination of waterlogged wood and wood charcoal provides the complete picture of past wood resource use. Linking dendrochronology and anthracology is linking wetland and dryland archaeology. It opens new avenues for dendrochronological research, especially in contexts and landscapes with rare or no wetland preservation. Charcoal analysis gives a more complete picture of wood usage because it includes fuel wood remains, thus refining ecological interpretations hitherto based solely on waterlogged timber. Dendrochronology is at the linking heart of archaeology and natural sciences. Dealing with archaeological woody finds, while applying natural science methods, and interpreting the data in a both archaeological and ecological way, it can serve to bridge still existing gaps between disciplines, and foster interdisciplinarity. However, dendrochronology itself needs the integration with anthracology and wood taxonomical studies, to fully develop a “palaeotree” as well as “palaeowoodland” perspective to make as complete use of the wooden legacy as possible, to improve our knowledge of past human development as well as climate and environment dynamics.


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The wooden findings of the Hallstatt saltmine – local or imported? Dendrochronology and chemical data will try to answer

M. Grabner1, M. Bolka1, J. Tintner1, M. Horsky1, M. Horacek2, H. Reschreiter3, K. Kowarik3, T. Prohaska1

1 University of Natural Resources and Life Sciences Vienna - BOKU, Vienna, Austria 2 BLT Wieselburg, Lehr- und Forschungszentrum Francisco Josephinum, Wieselburg, Austria

3 Natural History Museum Vienna, Vienna, Austria

Hallstatt is well known for its numerous wooden findings. Due to the rock salt – a perfect conservation of organic material – the wooden goods are in very good condition. Various types of artefacts were found: round logs acting as mining timber, tool handles, cups and hollow ware, tools and lightning chips (torches) in uncountable numbers. In the mine some stumps of felled trees were found, too. These findings are obviously of local origin. Tool handles were usually made out of the branch-stem connection of beech trees. At one excavation site numerous tool handles made of oak wood were found. There was (and still is) no possibility to grow oak trees in the vicinity of Hallstatt – due to the cold climate. So, these tool handles must have been transported to Hallstatt. To understand the supply of the mines, it is of high importance to know, whether the surrounding forests are able to sustainably deliver enough wood or if it has to be imported. To answer this question, an interdisciplinary project was set up. Archaeologists gave hints of places where the wooden goods might possibly come from - places of known human activity during the Bronze and Iron Age. Ten sites of prehistoric human activity close to known prehistoric trade routes were chosen. At all possible geological bedrocks within the sites, 15 trees of Norway spruce, Silver fir, European beech and Oak – if available – were sampled. Up to four “micro-sites” per site were sampled ending in maximum 120 cores per site and species. The cores were dendrochronologically dated and analysed by the chemists later on. A common period of 61 years (1960 to 2010) was chosen for further analyses. First results using just ring width show that a differentiation between the sites, which are close to Hallstatt, is not possible. The Gleichläufigkeit and the t-values for Ennstal (fir: 78, 10.4; spruce: 76, 5.7; beech: 69, 7.1) and Traunkirchen (fir: 75, 7.5; spruce: 68, 7.3; beech: 71, 6.5) are significant. For all sites, which are more distant to Hallstatt (Klagenfurt, Grossklein, St. Peter am Kammersberg in the south; Gmunden, Kobernausserwald, Eichetsham, Dendlreith in the north), the Gleichläufigkeit as well as the t-values were not significant. For prehistoric tree ring series, there will be no possibility to differentiate between Hallstatt and some other close sites, but there will be a clear signal, if the trees were growing in a wider distance. Dendrochronological data will now be added to chemical information. In this context strontium, carbon, oxygen and hydrogen isotopes have been exploited for the potential to identify the provenance of the wooden findings. Supported by the Austrian Science Fund FWF P23647-N19.


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Chronology of the Lusatian Culture population stronghold in Wicina (SW Poland) in the light of dendrochronological analyses

M. Krąpiec, E. Szychowska-Krąpiec Faculty of Geology, Geophysics and Environmental Protection, AGH – University of Science and

Technology, A. Mickiewicza 30 Ave., 30-059 Krakow, Poland ([email protected])

The stronghold in Wicina near Zielona Góra (SW Poland) is one of the most important posts of the Lusatian culture in Central Europe. The fall of the stronghold was connected with an invasion of the nomadic Scythians, tragic in its effects, because the population was exterminated and the buildings burnt. After the stronghold destruction that site was never inhabited again. Hence, the cultural beds retained almost complete movable materials; burnt ceramics, metals, ornaments, abundant objects from precious metals, as well as human vestiges. Excavation research of the stronghold site was led since the mid 1960s till the death of its director, Dr A. Kołodziejski in 1998. Recent works, aimed at completing earlier excavations led in two trenches, started in the years 2008-12. These excavations resulted in collecting over 1600 pieces of wood coming from the structure of the stronghold ramparts, palisades, roads, and buildings. Dendrochronological analysis was carried out for 1008 timbers, complying with the requirements of the method. Among them oaken samples dominated (591 pieces), then pine (292 pieces) and alder (107 ones). The measurements were also made for 8 beech samples, 6 of ash, and 2 of larch. Based on most convergent dendrograms of oak samples, the 321-year chronology WIC_AA1 was constructed. Its comparison with the subfossil oak chronology for S Poland (produced by M. Krąpiec) and with the oak chronology for SE Germany (U. Heussner) resulted in the absolute dating for the period 904-584 BC. This new chronology supplements the gap in the standard chronologies for SW Poland and presents a valuable standard for dating wood from that period. Rich comparative material allowed for dating over 90% of the oak samples. Exceptionally high similarity of dendrograms of trees growing in very similar conditions often enabled successful dating of relatively short, 30-50-year sequences. Hetero-connection with the oak chronology resulted in dating 8 alder samples, 4 ash trees, and 2 beech ones. Dendrochronological analysis of wood from Wicina indicates that construction of the rampart in the N part of the stronghold, together with the adjacent road (so-called older), was achieved in autumn 737 BC or spring 736 BC. Reconstructions of the structure (palisade, road and rampart) could have been made in the 590s(?) and 580s BC, most probably in 587 BC (works were finished in autumn 587 or in spring 586 BC). Later repairs of the palisade and the younger road were led in the 570s BC. The youngest dated element came from 571 BC and it could be used as a base for terminus post quem dating of the tragic end of the Wicina stronghold, connected with the invasion of the Scythians.


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A dendrochronological reassessment of three Roman vessels from the Netherlands: evidence of inland navigation between Gallia Belgica

and the limes of Germania inferior

K. Haneca1, E. Jansma2,3, M. Kosian2 1 Flanders Heritage Agency, Koning Albert II-laan 19, 1210 Brussels, Belgium

2 Cultural Heritage Agency of The Netherlands (RCE); PO Box 1600; 3800 PB, Amersfoort, The Netherlands

3 Utrecht University, Faculty of Geosciences, Budapestlaan 4, 3584 CD Utrecht, The Netherlands

The provenance of three Roman river vessels (De Meern 1, 4 & 6), excavated along the northern frontier of the Roman Empire in Germania inferior (limes), near the city of Utrecht, was reassessed. Oak timbers from De Meern 4 were felled around AD 100, for De Meern 1 around AD 148 and a single timber of De Meern 6 was cut after AD 158. Originally, but based on a relatively small number of reference data, their provenance was placed in the Netherlands. Dendrochronological dating and provenance studies involve comparison with dated chronologies representing archaeological objects or sites. In many cases, the assumption underlying such chronologies is that the provenance of the timbers is the same as their find location. Here, this assumption was discarded and the individual tree-ring series of the Roman ships and the reference series was reassessed regardless of their archaeological context. Reference data were downloaded from the ‘Digital Collaboratory for Cultural Dendrochronology’ (DCCD) at http://dendro.dans.knaw.nl together with their research documentation. The DCCD now includes a searchable repository containing all tree-ring data and research results from the Netherlands since the 1960’s as well as, among others, extensive datasets from Belgium. In total, 1450 dated growth patterns of oak from Roman-period sites from the Netherlands and Belgium, were extracted from the DCCD. Patterns showing strong similarities with individual patterns of De Meern 1, 4 and 6 were grouped together into ‘timber groups’ (TG’s). Then, the provenance of the TG’s was inferred from the organization level and spatial distribution of the archaeological sites represented in these groups. If a TG includes timbers from archaeological sites with a low to moderate level of organization, it is assumed that the timbers included in this group were harvested locally. The similarity between structural elements of the of Utrecht ships and the TG containing mainly material from present-day Flanders (northern Belgium) is exceptionally strong (tH:15.6 and %PV: 73.3, OVL: 315 years). Furthermore this TG is characterized by series from archaeological sites in Gallia Belgica with a low to moderate organization level. This indicates that the ships were built with oak from the lower-Scheldt region in present-day Flanders. Given the absence of Flemish oak in Roman land-based constructions along the Dutch limes, this provenance implies that the vessels were constructed in Gallia Belgica. Consequently, the geographical location of the final wreck sites of De Meern 1, 4 and 6 points at economic relations and inland-navigation routes between the lower-Scheldt region of Gallia Belgica and the Rhine-based limes of Germania inferior.


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http://dendro.dans.knaw.nl/

Dating of the roof of the Nyírbátor Calvinist Church

A. Grynaeus Hungarian Dendrochronological Laboratory, Budapest, Hungary

Hungary’s territory was devastated several times by different wars in the last five centuries (Ottoman conquest, Rákóczi insurrection, World War II), thus there are very few monuments with medieval timber roof truss. This is the reason why the investigation of the roof of the Nyírbátor Calvinist church is so significant which took place in 2014, based on the experiences of almost 25 years of Hungarian and ten years of Transylvanian research. The investigation aimed not only the dendrochronological dating of the monument, but we also did the art historical and architectural analysis of the timber roof truss, as well as we tried to detect the its building technology. A total amount of 24 oak samples have been taken from the structure, fifteen of them contained rings of the sapwood. Our statements are that

• the timber roof truss has been built of oaks cut in the same period, i.e. the roof has just one building phase,

• the structural anomaly in the western part does not indicate any chronological difference, it preserved the traces of a plan modification during the construction,

• the roof of the western (staircase) tower is contemporary with the timber roof truss of the church,

• the raising-piece found in the western gable is also contemporary with the other wooden elements,

• the timbers were cut and used between 1512–1525, • the timbers do not come from the same biotope, they were most probably acquired on

the market.


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The oldest roof structure in Transilvania

B. Tóth1, I. Botár2, A. Grynaeus3 1 University of Szeged, Szeged, Hungary

2 Csíki Székely Múzeum, Csíkszereda, Romania 3 Hungarian Dendrochronological Laboratory, Budapest, Hungary

The Lutheran church in Sibiu (Romania) was built in the 14-15th century. The roof structures above the chancel, cross-nave and nave have Romanesque and Gothic characteristics therefore a medieval dating was accepted, but never proved. The sampling and dendrochronological analysis made in 2012 finally confirmed that the silver fir structures were built in the middle of the 14th century and by the end of the century already a new reinforcement was made in most of the cases. Due to the actual knowledge the roofs of the Lutheran church in Sibiu are the oldest still standing structures in Transylvania. Our poster presents the structure, the sampling and the interpretation of the dendrochronological data


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New regional chronologies for eastern Austria – a basis for dendroprovenancing and dendroclimatology

M. Grabner, E. Wächter, S. Karanitsch-Ackerl, M. Bolka University of Natural Resources and Life Sciences Vienna - BOKU, Vienna, Austria

Precisely dated tree-ring series of a single species originating from living trees, historical and archaeological samples from a region are usually used to set up master-chronologies. But what is the definition of “regional”? Where do the borders have to be set? How should obvious timber transport be handled? Up to now, master chronologies separated into the main districts of Austrian forest communities – the Alpine region, the northern and southern foothills of the Alps and easternmost Austria – were used for dating at the BOKU tree-ring lab. After 20 years of data collection, new master chronologies were built. All sites (living trees as well as historical and archaeological objects) were put into a GIS-linked database. These point data were overlaid with topographic and thematic maps of forest communities and climate of eastern Austria. The first step was to build updated chronologies for the regions mentioned above. 1.386 sites or objects (more than 10600 samples) resulted in chronologies up to 2.900 years in length (mainly about 900 years in length) for Norway spruce (Picea abies), Silver fir (Abies alba), European larch (Larix decidua), Stone pine (Pinus cembra), Black pine (Pinus nigra) and oak (Quercus spp.). Austrian topography and geology are highly variable within small distances implying high variability in climate and vegetation. Together with the dense river network these prerequisites create opportunities and challenges for dendroclimatology and dendroprovenancing at the same time. During the last few years, several small-scale chronologies were built at the BOKU tree-ring lab for dendroclimatological analyses as well as for dendroprovenancing and questions of historical timber transport: (1) For the Weinviertel-region, provenancing (using standard crossdating statistics) was necessary to assure that only local timber is used for climate reconstructions. (2) Within the Limestone Alps, a huge number of living trees as well as historical timber from floating dams were combined to a small-scale chronology. (3) At the mountain Dachstein an almost 3.500 yearlong spruce/larch chronology was set up with the help of subfossile tree trunks from an alpine lake. (4) The big cities – like Vienna and Salzburg – were not able to meet their demand on wood locally. It could be shown, that logs and timber were floated to the cities on the rivers Danube and Salzach by comparing t-values of the dated samples with local and remote regional chronologies. A next step will be the set-up of additional small-scale chronologies for “hot spots” of provenancing (i.e. the Enns-Steyr region as the origin of wood for the Imperial Palace of Vienna) and “regions of interest” for climate reconstructions – especially the drier areas in eastern Austria – as well as for dating purposes.


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Forest Resources for Iberian Empires: Ecology and Globalization in the Age of Discovery (ForSEAdiscovery, a Marie Curie ITN project)

A. Crespo Solana1, M. Domínguez-Delmás2, I. García-González2, U. Sass-Klaassen3, T. Wazny4, N. Nayling5

1 Centro de Ciencias Humanas y Sociales, Centro Superior Investigaciones Científicas, Madrid, Spain

2 University of Santiago de Compostela, Department of Botany, Lugo, Spain 3 Forest ecology and management, Wageningen University, Wageningen, The Netherlands

4 Institute for the Study, Conservation and Restoration of Cultural Heritage, Nicolaus Copernicus University, Torun, Poland and University of Arizona, Laboratory of Tree-Ring

Research, Tucson, USA 5 School of Archaeology History and Anthropology, University of Wales Trinity Saint David,

Lampeter, United Kingdom

In the Early Modern Age (16th-18th centuries) the construction of ocean-going ships was paramount to the development of cultural encounters within Europe and beyond in what became the Age of Discovery and European expansion. In the case of the Iberian Empires, the establishment of new trade routes brought up the need for armed merchantmen, galleons and smaller vessels, placing unprecedented demands on Iberian forests for the supply of construction timber, mostly oak (Quercus spp.) and pine (Pinus spp.). Forestry and sea power became inextricably linked, creating new geopolitical tensions, alliances and forest regulations. Key questions in this context are: could Iberian forest resources sustain the increasing demand of sound timber, or was the wood imported from elsewhere? If so, how were the trade networks organized? And did the lack of raw material force the technological changes occurred in shipbuilding in the 16th century, or were they a result of exchange between Mediterranean and Atlantic shipbuilding traditions? The four-year ForSEAdiscovery project will address these questions through a multidisciplinary and innovative research program promoted by a consortium of nine full participants and five associated partners from eight European countries (Spain, Portugal, France, UK, The Netherlands, Denmark, Poland and Sweden) and USA. Historical research, underwater archaeology, and dendro-disciplines including tree-ring research, wood anatomy and geo/dendrochemistry will be combined to study the exploitation of Iberian and other European forest resources for shipbuilding during the Age of Discovery and European expansion. A geographic information system will be used to integrate and visualize layers of information provided by the different disciplines, allowing the study not only of historical utilization of forest resources for shipbuilding, but also the development and interaction of timber-trade networks in Europe during the Early Modern period. In this manner, the ForSEAdiscovery project will contribute to improve the understanding of our historical past, our cultural heritage, and the use of forest resources during that crucial time in history.


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Which matters most in the formation of intra-annual density fluctuations in Pinus pinaster: age or ring-width?

F. Campelo1, J. Vieira1, G. Battipaglia2,3, M. de Luis4, C. Nabais1, H. Freitas1, P. Cherubini5 1 MedDendro Lab., Centre for Functional Ecology, Department of Life Sciences, University of

Coimbra, Coimbra, Portugal 2 Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second

University of Naples, Caserta 81100, Italy 3 Centre for Bio-Archaeology and Ecology, Institut de Botanique, Ecole Pratique des Hautes Etudes

(PALECO EPHE), University of Montpellier 2, Montpellier F-34090, France 4 University of Zaragoza, Department of Geography and Regional Planning, C/Pedro Cerbuna 12,

50009 Zaragoza, Spain 5 WSL Swiss Federal Institute for Forest, Snow and Landscape Research, CH-8903 Birmensdorf,

Switzerland

In the Mediterranean area, intra-annual density fluctuations (IADFs) are triggered by short-term climate variations during the growing season. It is known that the formation of these anatomical structures is dependent on size and age, which can represent a problem during the extraction of the environmental signal from IADF chronologies. We present a new method using a two-step approach to remove the effect of tree ring width from IADF chronologies. We have compared the climatic signal of IADF chronologies obtained by the proposed method with previous methods employing bootstrap analysis, using 160 Pinus pinaster tree cores from an even-aged stand on the west coast of Portugal. Our results showed that the climatic signal of IADF chronologies was strongly affected by the standardization method used, and that it could be improved by removing the effect of predisposing factors (cambial age and tree-ring width) on IADF formation. Additionally, new climatic information was revealed when the effect of tree-ring width was removed from IADF series. Finally, we propose that this new method should be used for other species and across larger geographical areas in order to confirm its capacity to remove noise from IADF chronologies and to improve their intra-annual climatic signal.


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Can the structure of dormant cambium and the widths of phloem and xylem increments be used as indicators for tree vitality?

J. Gričar1, Š. Jagodic1, B. Šefc2, J. Trajković2, K. Eler3 1 Slovenian Forestry Institute, Department of Yield and Silviculture, Ljubljana, Slovenia

2 Faculty of Forestry, University of Zagreb, Zagreb, Croatia 3 Biotechnical Faculty, Department of Agronomy, University of Ljubljana, Ljubljana, Slovenia

In Slovenia and Croatia, oaks (Quercus robur L. and Q. sessiliflora Salisb.) are economically and ecologically very important tree species, representing 7 and 22 %, respectively, of the entire wood stock. As in many European countries, a trend of decreasing vitality of Q. robur in the form of defoliation and reduced height and girth increment has been observed at most sites in recent decades. We investigated the structure and width of the dormant cambium and of the increments of phloem and xylem of Quercus robur to estimate their potential as indicators for tree vitality. The samples were taken from three woodlands, two in Slovenia (KRA and MUS) and one in Croatia (KOB), with reported tree decline. In December 2009, microcores containing inner phloem, cambium and outer xylem were collected from living trees at 1.3 m above ground. The tissues were fixed, embedded in paraffin, cut on a rotary microtome, and stained with safranine/ astra blue water mixture. The cross-sections were examined with light microscope and image analysis system. The number of dormant cells seems to reflect the initial capacity of the cambium to accomplish cell division. With the exception of two trees at KRA, cell production was always higher on the xylem side than on the phloem side. The annual phloem increments were narrower, less variable among trees and with clear lower and upper limits. With increased cambial cell productivity, the share of the xylem in the total annual radial increment increased following a curvilinear function. In trees with an annual radial increment > 3.5 mm, the xylem size represented more than 90 % of the total radial growth. The anatomical variables analyzed show that the most limiting environmental conditions seem to prevail at KRA, whereas the conditions at MUS seem to be most favorable in terms of radial growth. The width and structure of xylem and phloem increments, the number of dormant cambial cells and their inter-relationships can provide additional information on the vitality of oaks.


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Earlywood vessel formation related to crown phenology quantified from dry mater content in Quercus pyrenaica

G. Guada1, I. García-González1, G. Montserrat-Marti2 1 Department of Botany, EPS, Univ. of Santiago de Compostela, Lugo, Spain

2 Pyrenean Institute of Ecology (IPE-CSIC), Zaragoza, Spain

Time series of earlywood vessel size in ring-porous species have been proved to be powerful climate proxies. But in order to correctly interpret the climatic signals recorded, it is fundamental to understand the time window of earlywood vessel development, and its relation to leaf unfolding, as both processes (resumption of primary and secondary growth) must be closely related. Branch formation is conventionally studied by visual observation (swollen buds, bud break,..) followed by shoot length recording, but the measurement of dry mater content (DMC) of branch fractions at different developmental stages has been proposed as a useful method to quantify primary growth (Palacio et al., 2008) The aim of this work is to explore the relationships between vessel formation, recorded at breast height, and branches phenophases, quantified by both the visual and DMC methods. In northwestern of Spain 11 Quercus pyrenaica trees were sampled at 10-day intervals at the same site during the 2013 growth period for xylogenesis (two microcores from opposite sides of the stem). From the same trees, a three-year-old branch was analysed for DMC of buds, leaves and stems out of the current and the three preceding years, and visual appreciation of branch phenophases and shoot growth length were recorded in the field. Both phenological methods provide similar results, even during the swollen bud phase, which is not generally considered because of its imprecise differentiation with binoculars. Shoot growth rate peaked concurring with the lowest DMC, when earlywood vessels were functional enough to fulfil water requirements for shoot growth, although first row vessels were developed in advance, between buds swollen and leave unfolding. These results confirm the usefulness of DMC to quantify primary growth complementing qualitative methods, and the contribution of both techniques to relate primary and secondary growth during growth resumption in spring.

REFERENCES Palacio, S., Maestro, M., Milla, R., Camarero, J.J., Albuixech, J., Pérez-Rontomé, C. & Montserrat-Martí, G. (2008). Seasonal variability of dry matter content and its relationship with shoot growth and non-structural carbohydrates. New Phytologist 180: 133-142.


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Tree size and winter carbon storage regulate the linkage between wood formation and vessel conductivity in two ring-porous oak

species

G. Pérez-de-Lis1, I. García-González1, V. Rozas2, J.M. Olano3 1 Department of Botany, University of Santiago de Compostela, Lugo, Spain

2 Laboratory of Dendrochronology, Austral University of Chile, Valdivia, Chile 3 Área de Botánica, EUI Agrarias, University of Valladolid, Spain

The balance of tree carbon reserves is critical to understand metabolic trade-offs between growth, reproduction and resistance to stresses, such as drought events. In adult deciduous oaks, sapwood is a major reservoir of non-structural carbohydrates (NSC) pools. The amount of NSC stored in winter is critical for oaks performance due to their major carbon demand for winter maintenance, and the need of stored reserves for canopy development and early secondary growth in spring. In this study we aimed to model the relationship between sapwood NSC winter concentration, wood formation, and vessel conductivity in two ring-porous oak species, Quercus robur and the more drought-tolerant Quercus pyrenaica. Three sites located along a drought gradient in NW Spain were selected for this study, and 40 trees of each species per site (n = 240) were sampled. Stem diameter, tree height, and canopy cover were individually recorded. One sapwood core per tree was taken in December 2012 and February 2013. Sugars and starch concentrations were quantified for the whole sapwood section in all the cores. Moreover, image processing applied on additional cores collected in October 2013 allowed us to quantify the percentage of sapwood, earlywood vessel conductivity in 2012, and earlywood and latewood widths in 2013. Structural equation modeling (SEM) was used to find causal relationships between tree size, NSC amount, vessel conductivity, and earlywood width. Additionally, we performed univariate generalized linear models to identify those factors that significantly affected latewood width. In both species, SEM revealed that earlywood conductivity positively influenced earlywood width of the following year, involving stored NSC in winter. This process showed to be strongly influenced by stem diameter and independent of the study site. In turn, univariate models for latewood formation demonstrated differences among species. Canopy cover, tree height and February starch content affected latewood width, but only in Q. robur. However, both species showed a positive relationship between latewood width and sapwood proportion, while the effect of previous earlywood width was almost negligible. This study contributes to shed light on the mechanism relating the status of carbon reserves and secondary growth of ring-porous species, and reflects the importance of size on tree performance. Specifically, conductance efficiency resulted from wider earlywood vessels enhances NSC supply, which is invested in growth after winter dormancy.


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Phenological variation in xylem and phloem formation in Fagus sylvatica from two sites in Slovenia

P. Prislan1, J. Gričar1, M. de Luis2, K.T. Smith3, K. Čufar4 1 Slovenian Forestry Institute, Ljubljana, Slovenia

2 University of Zaragoza, Dept. Geografía, Zaragoza, Spain 3 USDA Forest Service, USA

4 University of Ljubljana, Biotechnical Faculty, Dept. of Wood Science and Technology, Ljubljana, Slovenia

Xylem and phloem formation, as well as cambium and leaf phenology, and their relation to weather factors, were studied from 2008 to 2010 in beech (Fagus sylvatica L.) trees from two sites in Slovenia with different elevations and weather conditions: Panška reka (PA) (400 m a.s.l.) and Menina planina (ME) (1200 m a.s.l.). During the vegetation periods leaf phenology and dynamics of xylem as well as phloem formation were monitored. Leaf unfolding, onset of cambial cell production and increased number of active phloem cells occurred simultaneously for each site: in mid-April at PA and in the first week of May at ME. Maximum rate of xylem cell production occurred at PA from 20 May until 9 June and about two weeks later at ME. Maximum phloem cell production occurred more than 1 month earlier at both sites. Cessation of xylem and phloem cell production was observed at PA around 19 August and around 10 days earlier at ME. Differentiation of the last-formed xylem cells was concluded by mid-September at both plots. Year to year variability of the observed phases was not statistically significant but the differences between the sites were. Phloem formation seems to be less subjected to fluctuations in environmental conditions since the growth ring widths were comparable at both sites. The relationship among xylem ring width, maximum cell production and duration of the growing season, suggests that xylem ring widths in beech at lower elevations depended more on the length of the growing season than on the rate of cell production. The opposite was observed at higher elevations. Time of maximal phloem cell production, which occurred shortly after the onset of cell production, was related to weather. Subsequent phloem formation seems to be endogenously driven and the phloem ring widths were similar at both sites. Temperature and growing degree days before the occurrence of most of the observed phenological phases significantly differed between the sites. This demonstrates that the observed differences in xylem and phloem formation between the sites can be attributed to high intra-specific plasticity of beech.


70

Factors affecting daily variations of Scots pine stem size at the end of vegetation season

M. Tamkevičiūtė1, R. Pukienė2, J. Taminskas1, V. Šmatas1 1 Nature Research Centre, Vilnius, Lithuania

2 Vytautas Magnus University, Kaunas, Lithuania

High precision dendrometers are efficient tools for the investigation of the dynamics of tree radial growth as well as the changes in tree stem size, physiological conditions, dependence on hydrological and meteorological conditions and tree ring formation studies. In our study dendrometers DRL 26 were used to identify the impact of climatic and microclimatic conditions on tree physiology and stem size changes. The dendrometers were installed on 5 Scots pine (Pinus sylvestris L.) trees growing in raised bog habitats. The sites for installation of the dendrometers were selected by following criteria: representative research location, degree of anthropogenic disturbance, even distribution of research sites in Lithuania and estimation of climatic, hydrologic and anthropogenic conditions. Considered all these criteria three sites in raised bogs were chosen, in which automatic data loggers for recording water temperature and, water level in wells and dendrometers were installed in measurement areas. Research period lasted from the end of the vegetation to the beginning of dormancy season. Factors affecting tree stem size changes and synchronicity among different trees at the end of vegetation season were established. Daily variations and reaction of stem size to moisture fluctuations almost ceased at the beginning of November when mean daily temperature dropped below +7C°.


71

Coupling stem water flow and structural carbon allocation in a changing climate: the Lötschental case-study (LOTFOR)

R.L. Peters1, D. Frank1, K. Treydte1, P. Fonti1 1 Swiss Federal Research Institute WSL, CH-8903 Birmensdorf, Switzerland

Photosynthesis represents the process where the water cycle meets the carbon cycle, driving plant growth. For each kilogram of carbon generated by photosynthesis, a plant transpires between 100 and 1000 kilograms of water. Yet, these quantities are influenced by the environmental setting and species which play a key role in determining interactions between the water and carbon balance from single plants to the land-atmosphere fluxes across the Earth. With the LOTFOR (PhD) project we aim at clarifying the coupling between the carbon and hydrological cycle in the context of changes in temperature and water availability by quantifying water flow and growth processes occurring in the stem of two conifer tree-species (Picea abies and Larix decidua). We will use data from a unique research setting located along a temperature (altitudinal) gradient and at contrasting wet and dry sites (Lötschental in Switzerland). Data collected in the project on plant-water relations (sapflow and stem diameter variations, soil, xylem and leaf water oxygen isotopes) will complement multi-annual high resolution measurements of tree growth (weekly xylogenesis observation, hourly stem size variation, tree-ring width, cell anatomy and density profiles) as indicators for structural carbon allocation. This data provides a comprehensive framework to link variability in the carbon and hydrological cycles. We want to improve our process-based understanding of how daily to annual structural carbon allocation (e.g., amount and shape of tracheids) in the forming ring is linked with the water flowing through the stem. Therefore, we aim to refine existing models that link water and sugar transport in living trees (e.g., De Schepper & Steppe 2010). The refined model will serve as a basis to link past climatic, tree-ring width and isotope data, and will be used for predictions of forest responses under a changing climate. In our view detailed simulations of the water-carbon relationships is the foundation for a better process-based understanding of how climate change factors affect the tree-ring anatomy and growth in conifers. With our poster we would like to provide information on the research setting of the LOTFOR study in addition to the models we aim to apply.

REFERENCES

De Schepper, V., & Steppe, K. (2010). Development and verification of a water and sugar transport model using measured stem diameter variations. Journal of Experimental Botany 61: 2083-2099.


72

Annually resolved forest growth - first results from a Swiss dendrochronological biomass network

S. Klesse1,2, D. Frank1,2 1 Federal Research Institute WSL, Birmensdorf, Switzerland

2 Oeschger Centre for Climate Change Research, Bern, Switzerland

Forest ecosystems cover around 30% of the terrestrial land surface and on average absorb 1.1 +/- 0.8 petagrams of carbon each year – approximately 30% of annual anthropogenic emissions [1]. However, the forest sink is highly variable in space and time and is associated with high uncertainties in both its magnitude as well as the driving ecological and climatic processes. Long-term and large-scale empirical data are thus required to improve our understanding of possible future trajectories of ecosystem services provided by forests. In this study we sampled 22 plots (350-1800 m2) along a climatic gradient in Switzerland to analyze the influence of climate and stand characteristics on annual forest productivity. The fixed plot sampling design, including tree cores from all trees >5.6cm diameter at breast height independent of their species in a circular area, allows for easy upscaling and the estimation of absolute annually resolved woody biomass increment data with a minimum of sampling bias related to common dendrochronological studies [2]. Annual productivity estimates for the 1980-2009 common period range from 1660 - 10950 kg ha-1 year-1 appear to be mostly driven by stand density and moisture conditions throughout the growing season and autumn. Preliminary results show higher absolute annual variability in stands with higher overall productivity (r2=0.57, p<0.001), which is in line with Babst et al. [3], but no significant trend in the relative variability (13-30%) can be observed. Maximum deviations in biomass increment can be up to 60% from the common period mean and are caused by climate extremes (e.g. drought) or severe disturbances (e.g. larch budmoth outbreak). Higher annual variability is further related to stands with lower species mixture, suggesting higher tolerance to climate variations and disturbances in mixed stands. However, due to juvenile trends, management activities and other disturbances it is up to now (low overall plot number) difficult to attribute longer-term trends in biomass increment to increased temperature, drought stress or fertilization effects (N deposition, CO2). Nevertheless we propose that well replicated, representative tree-ring datasets have a huge potential to complement the rather short-term and low-resolution forest inventory monitoring data to gain knowledge about annual changes in forest productivity even well before monitoring started. Furthermore, these detailed site level data shall be used to validate global scale vegetation models.

REFERENCES

Babst F, Bouriaud O, Papale D, et al. (2014) Above-ground woody carbon sequestration measured from tree rings is coherent with net ecosystem productivity at five eddy-covariance sites. New Phytologist 201: 1289-1303. Nehrbass-Ahles C, Babst F, Klesse S, et al. (2014) The influence of sampling design on tree-ring based quantification of forest growth. Global Change Biology: n/a–n/a. Pan Y, Birdsey RA, Fang J, et al. (2011) A Large and Persistent Carbon Sink in the World’s Forests. Science 333: 988–993.


73

Is blue data better climate proxy than traditional tree-ring widths?

S. Bijak, A. Bronisz, K. Bronisz Laboratory of Dendrometry and Forest Productivity, WULS-SGGW, Warszawa, Poland

The Blue Reflectance (BR) has recently become widely applied tree-ring parameter that proved to be efficient in climate reconstructions. It is usually used as a surrogate of maximum wood density. Our objective was to compare the climate signal in BR data with the information given by traditional dendrochronological data – tree-ring widths (TRW) Research material consisted of increment cores taken from three native (Abies alba, Larix decidua and Pinus sylvestris) and three alien (Abies grandis, Pseudotsuga menziesii and Thuja plicata) tree species growing in a ‘common garden’ conditions in Rogów Forest Research Station (central Poland; 51°49' N, 19°53' E). 15 samples per each species was collected and prepared according to standard procedures for further dendroclimatological analyses. TRW and BR were measured using CooRecorder software and then detrended towards series of annual sensitivity. Those values were correlated with climate data from Rogów meteostation (1924-2010). Monthly mean, minimum and maximum temperature as well as precipitation were used. Climate-growth relationships obtained for both proxies were compared.


74

On the influence of drought on ring width and earlywood density of different softwood species and provenances grown in eastern Austria

M. Grabner1, S. Karanitsch-Ackerl1, K. Mayer1, J.-P. George2, R. Klumpp1, S. Schüler2 1 University of Natural Resources and Life Sciences Vienna - BOKU, Vienna, Austria

2 Federal Research and Training Centre for Forests, Natural Hazards and Landscape, Vienna, Austria

In lowland forests with high temperatures and limited precipitation, the occurrence of drought is a limiting factor for tree growth. Soil conditions and precipitation are influencing the availability of water for the trees. Due to global warming, temperature-induced droughts seem to become a serious problem. The eastern part of Austria is characterised by low precipitation and high temperatures in summer. Different broad leaf tree species as well as conifers are growing in this area. Softwood species are of high economic importance here, but are also most affected by drought periods. In this study, the analysis of the ring width and earlywood density from seven provenance trials of Norway spruce (Picea abies), different Pine species (Pinus nigra, P. ponderosa), European and Hybrid larch (Larix decidua, L. decidua x kaempferi), different Fir species (Abies alba, A. borisii-regis, A. bornmuelleriana, A. cephalonica, A. cilicica, A. nordmanniana) and Douglas fir (Pseudotsuga menziesii) revealed interesting differences in the reaction of the trees to drought. As most of these plantations are young (20 to 35 years), data treatment had to be done with special care. The data were detrended with a 15-year-spline to highlight short-time influences due to climate. 1992 and 2003 were drought years in eastern Austria as well as in Scandinavia (1992) and western Europe (2003). The deviation of these rings from the mean value of indexed ring width / earlywood density (=1) was studied. Interestingly, the ring of the year 2000 showed much stronger deviations than the two well-known drought years mentioned above. 2000 was characterized by dry and warm spring and early summer. In 2003, smaller ring widths were formed (expressed in median values below 1). The ring width 1992 of the fir species and provenances were at the level of 1 or slightly above – in contrast to other species, which showed decreased ring-width. Earlywood density is said to be drought relevant and mainly related to warm and dry late winter and spring. During drought stress, the trees are forming smaller cell lumina – ending in higher density values. This was seen in 1992 but not in 2003. The highest earlywood density values appeared in 2000. Supported by the Austrian Science Fund FWF TRP122-B16 Softwood for the future.


75

http://bfw.ac.at/rz/bfwcms.web?dok=4636

X-ray microdensitometry applied to Pinus taeda as a dendroecological data source

M. Dobner Jr.1, M. Tomazello F°2 1 Prof. Dr., Universidade Federal de Santa Catarina, Curitibanos, SC, Brazil

2 Prof. Dr., Univesidade de São Paulo, ESALQ, Piracicaba, SP, Brazil

Pine plantations cover 1.6 million hectares in Brazil and are an important source of timber in the country. Pinus taeda is the most planted one, mainly concentrated in the southern highlands, where the climate is humid and subtropical, with 1,800 mm rainfall well distributed during the entire year. Soils are rich and of volcanic origin. Altogether providing very good growth conditions: over 50 m³ ha-1 year-1 for 20-years-long production periods. In the present study, cross sectional discs were sampled from 30-years-old trees grown in stands with an initial density of 2,500 trees ha-1, subjected to four thinning intensities: without, moderate, heavy and extreme, where none, 1, 2 or all competitor trees were removed at age 5 years in order to favour 400 potential crop tree candidates ha-1. Later on, and until trees reached 15 years of age, up to five thinnings were carried out reducing the number of trees down to 400 trees ha-1 in the moderate and heavy variants, while reducing it to 250 trees ha-1 in the extreme one. Wood samples at 1.3 m were obtained (10 mm in height and 1.7 mm ± 0.02 mm in width), a radial segment from pith to bark. Wood strips with 12 % of moisture content were scanned using a direct x-ray microdensitometer (QTRS-01X, linear resolution of 0.004 mm). A fixed threshold density at 0.550 g cm-3 was fixed, thus values above and below represented the late- and earlywood, allowing ring-width delimitation. Annual ring width and densities were averaged from two radii per tree. Statistical analyses were based on a fully randomised design. On average, the differences between ring width measurements through x-ray and direct measurement differed ± 0.1 mm, indicating that the threshold of 0.550 g cm-3 accurately delimitated the boundary of early- to latewood and vice versa. Mean ring widths varied from 6−9 mm, reaching a maximum of 22 mm during the first 3−6 years regardless of thinning intensity. In the figure, ring densities for the thinning variants are given. Arrows indicate the year at which thinning took place. Parentheses indicate only moderate and heavy variants were thinned. Only punctual differences between the ring densities produced in the different thinning variants were observed. A sharp decrease in ring density at age 28 years for all treatments was observed. Since it happened ≥ 13 years after the last thinning interference, it cannot be related to them. In fact, a drought period was detected at this year, when from March−June only 230 mm of rainfall was observed, less than half of the average for this period (> 500 mm), during which latewood is formed. Although additional analyses are needed, results indicated that x-ray micro-densitometry provides suitable information for dendroecological analysis of P. taeda grown in southern Brazil, allowing a better understanding of growth and its relationship with meteorological conditions.

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76

A 480-year chronology of earlywood vessels of oak in the Ancares Mountains (NW Spain)

M. Souto-Herrero, I. García-González Department of Botany, EPS, Univ. of Santiago de Compostela, Lugo, Spain

In this work, we present a long chronology of earlywood vessels of oak (Quercus robur L.) which, to our knowledge, constitutes the longest chronology of this proxy developed so far. This chronology was obtained at a site located in the eastern mountains of Galicia (Ancares), where were sampled more than twenty trees located on a sunny slope known as Monte da Vara. This is an area of steep slopes and 900-1400 m of altitude, where very old trees (400-500 years) are scattered among a dominant stratum with trees of different ages. For this analysis, we sampled a representative number of trees older than 350 years, as well as others up to 150 years to give robustness to the chronology, taking two cores per tree. We measured and dated the tree rings, and afterwards the earlywood vessels larger than 10,000 µm2 of each ring were also measured using image analysis. For this, we applied new tools we recently developed, specifically for vessel recording (VesselJ, a plugin developed for ImageJ), and for assigning the vessels to the correct ring (Autovasos). The combination of both tools showed that it is possible to construct a long chronology of earlywood vessels efficiently and in a reasonable time period. Vessel measurements were finally used to derive several variables, which were expressed as time series, considering the distribution of vessel size and number for each ring. The lenth of the time series comprised more than 480 years (1420-2003). Among all, the mean vessel area proved to be very different from ring width, and should be used in combination with climatic records.


77

Tree-ring width, earlywood vessel area of red oak and their relationship with climatic factors in Latvia

R. Matisons1, J. Jansons2, U. Neimane1, Ā. Jansons1 1 LSFRI “Silava”, Rigas Str. 111, Salaspils, Latvia, LV2169

2 Forest Competence Centre, Rigas Str. 111, Salaspils, Latvia, LV2169

Red oak (Quercus rubra L.) in Latvia is an introduced species, which is promising for future silviculture due to robustness to environmental hazards and productivity compared to native broadleaved species. At present, climatic conditions in Latvia might be considered to be similar to northern limit of natural distribution of red oak, thus under warming of climate, changes in growth of red oak are expected. Retrospective analysis of tree-growth-climate can provide valuable knowledge on reaction of growth to past climates, necessary for projecting possible changes of growth of red oak in future. Red oaks growing in three experimental plantations (two plantations in western and one plantation in eastern part of Latvia were sampled) were sampled for dendrochronological analysis. Increment cores from 23 and 10 dominant canopy oaks were collected in western and eastern region of Latvia, respectively. Tree-ring width (TRW) and lumen area of first earlywood vessel for each tree ring (VLA) were measured. Time series were processed using standard dendrochronological techniques. Similarity of wood formation among trees was assessed by PCA. Effect of climatic factors (mean monthly temperature and precipitation sum) was determined by Pearson correlation and response function analysis using program DendroCLIM2002. Measurement series covered period from 1902 to 2013. High frequency variation of TRW and VLA showed different patterns of variation in western and eastern region of Latvia, as previously observed for pedunculate oak (Matisons et al., 2012). Nevertheless, both tree-ring proxies showed high GLK values (~ 0.65) between sites, while correlation between chronologies was ~ 0.5–0.6 for TRW and ~ 0.3–0.5 for VLA, suggesting differing variation patterns. In all sites temperature in previous summer appeared as the main limiting factor for TRW, while in western region effect of current summer temperature was also significant. VLA was affected generally by temperature in cessation of previous growing season and during the dormancy, similarly as observed for pedunculate oak; however, coefficient values were considerably lower. Climatic factors, significant for TRW had changed particularly in eastern region, where temperature of previous summer and current July precipitation became significant since mid-part of 20th century. Regarding VLA in western region of Latvia, temperature in previous spring lost its sensitivity and temperature during dormancy became significant. In eastern region, temperature at cessation of previous growing season and January precipitation became significant for VLA, while effect of temperature in previous August changed diametrically and previous spring temperature lost its significance. This study was founded by Forest Competence Centre (ERAF) project «Methods and technologies for increasing forest capital value» (No. L-KC-11-0004).

REFERENCES

Matisons, R., Elferts, D. & Brūmelis, G. (2012). Changes in climatic signals of English oak tree-ring width and cross-section area of earlywood vessels in Latvia during the period 1900–2009. Forest Ecology and Management 279: 34–44.


78

A high ring-width cross-dating performance of Cedrela odorata trees from a Peruvian Amazon rainforest

M. Tomazello Filho¹, M. Silveira Lobão², A. Schipper Guerovich³, C.I. Huaman Calderón³, F.A. Roig4, P.A. Zevallos Pollito³

1 University of São Paulo, Piracicaba, Brazil 2 Federal University of Acre, Rio Branco, Brazil

3 Amazon National University of Madre de Dios, Madre de Dios, Peru 4 IANIGLA, CCT CONICET, Mendoza, Argentina

Tropical trees are increasingly capturing the interest for tree ring studies. Although some tree species and environments produce ring-width time series that are difficult to cross-date, the need for long and reliable tree-ring records for environmental reconstructions in the tropics imply the exploration of new tree species and regions for potential application on palaeoenvironmental and forestry studies. The southern Peruvian Amazon region, is home of a low-lying rainforest with a high plant diversity including large Cedrela odorata trees. Trees of ca. 1 m in stem diameter were cored to produce 33 annual-resolution tree ring width series (radii) from eight trees. Series were submitted to cross-match comparisons following standard dendrochronological procedures and a master series length between 1825-2007 (183 yrs) was produced. Results showed a high inter-tree correlation performance between all trees with r = 0.59 (P<0.01) and average sensitivity of 0.38. A similar strength in the inter-series correlation (r = 0.57; P<0.01) was obtained from a C. odorata forest at the Pando area located ca. 100 km east to our study area. Moreover, an additional C. odorata tree-ring chronology developed for the Acre region and located at a distance of 300 km from the Madre de Dios tree-ring chronology, reaches an inter-chronology similarity of r = 0.40 (n = 103; P 0.01). Thes stimulated results show that at the trinational Madre de Dios/Peru - Acre/Brazil – Pando/Bolivia region in southwestern Amazonia, Cedrela odorata may be seriously considered as a promising tree species for expanding past environmental inferences in the New World tropics.


79

Tree ring evidence of flash flood activity in Tatra Mountains

J.A. Ballesteros-Canovas1, R.J. Kaczka2, B. Czajka2, K. Janecka2, M. Lempa2, M. Stoffel1 1 Laboratory of Dendrogeomorphology, Institute of Geological Sciences, University of Berne, CH-

3012, Berne, Switzerland 2 Faculty of Earth Science, University of Silesia, Sosnowiec

Hydrologic process such as flash floods represents common hazards in Tatra Mountains. Because the densely populated regions in Poland and the impacts of climatic changes are expected to increase adverse impacts related to flash floods. Existing historical archives and previous studies point to extreme past floods in the foothills, however the lack of a long-term systematic and spatially distributed record along the mountain streams prevents the analysis of process variability in the source areas of the Tatras. As a consequence, there are still many uncertainties about the flash-flood frequency at the regional scale and their triggers and climatic controls. Here, we present a dendrogeomorphic study focused on four poorly-gauged torrential streams located along the northern slope of the Tatras Mountains. We focus on (i) the temporal and spatial reconstruction of past events and the (ii) peak discharge estimation of these events based on paleofloods techniques using dendrogoemorphic evidence. Six sectors have been sampled and more than 1100 increment cores were obtained from trees. Then, standard dendrogeomorphic procedures have been performed for sample analysis and for the dating of events. We focused mainly on scars in stems because they are considered reliable paleostage indicators. Therefore, based on the scar height and two-dimensional hydrodynamic models, we assessed related paleodischarge. Preliminary results show intense and highly variable flash-flood activity. Based on our results, we discuss the regional spatial pattern of events, their climatic triggers and relationship with the largest flood events of the past 100 years in the region.


80

Tree rings and snow avalanche modelling. Case studies from the Tatra Mountains

M. Lempa1, B. Gądek1, K. Janecka1, R.J. Kaczka1, Z. Rączkowska2 1 Faculty of Earth Science, University of Silesia, Sosnowiec

2 Institute of Geography and Spatial Organization, Polish Academy of Sciences, Cracow [email protected]

Snow avalanches are the major natural hazard, which influence on natural environment, touristic infrastructure and also endanger humane life in the Tatra Mountains. Activity of snow avalanches effects landscape, especially forest and controls the course of timberline. They are main geomorphic processes limiting warming-related upslope advance of the subalpine forest. The aim of this study was to reconstruct the spatiotemporal dynamic of the snow avalanches in two chutes: Biały Żleb and Żleb Żandarmerii as a case study using the tree-ring records coupled with one-dimensional snow movement modelling. The standard dendrogeomorphological and GIS techniques were used to date and assess the range of the events. The modelling was performed based on the Aval-1D numerical avalanche dynamics program. Detailed geomorphological map of avalanche catchment was prepared based on the records of the past events, historical maps, aerial photos and LIDAR digital terrain model.. More then 700 of the injured and decapitated trees growing along the avalanche paths were sampled and dated. All existing historical maps and aerial photos spanning from 1938 to 2012 were investigated reveling the relatively stable position of the timberline. The results of tree-ring analyses were coupled with GIS data to bring additional information about the spatiotemporal dynamic of events. The result of tree-ring analyses complemented this data and allowed to extend the event chronology up to 200 years. The known and reconstructed avalanche events were modeled and complex system of climate-relief-snow avalanche was analysed.

The study were supported by the National Science Centre, project no 2011/03/B/ST10/06115.


81

Identifying and quantifying the impact of late frosts on radial growth of common beech (Fagus sylvatica L.) from southeastern Poland

L. Chojnacka- Ożga, W. Ożga Warsaw University of Life Sciences, Faculty of Forestry

The aim of this research is to identify and quantify the impact of late frosts on growth of common beech growing on the eastern edge of its range, in southeastern Poland. Late frosts are considered as important, ecological events that strongly affect beech vitality and influence the geographical range of beech Studies were conducted in 10 beech stands, older than 150 years, located at different altitudes, from 285 m to 950 m a.s.l, Together about 500 samples were collected and treated employing the standard dendrochronological methods. Site chronologies were established and compared to climatic and phenological data. Climatic database was built containing daily minimum temperature series from 12 climatic stations located near the research plots. Phenological data were fragmented and obtained from several stations, missing data were simulated according to Rötzer et al. (2004). The analysis covered the years 1910 -2010, the occurrence of late frost below -3OC in the days of or immediately after leaf unfolding were taken into account (Dittmar et al. 2006) The research proved that a several number of severe growth minima in the tree-ring series on each research plots could be related to late frost. The number of those cases depended on the altitude and exposition of the site. In lower altitudes (~300 m a.s.l.) signals of late frost were found only twice during the last century: in 1935 and 1953. With increasing altitude also increased the number of growth minima, that can be related to late frost: in altitudes about 600 m a.s.l. occurred four signals of late frost events (1935, 1953, 1980, 1988), above 900 m a.s.l. - eight ones (1927, 1935, 1952, 1965, 1974, 1978, 1980 and 1988). In those years growth reduction occurred in more than 90% of trees and its quantifying, in relation to the average of the ten previous years, was related with altitudes. Based on case studies of the years 1935, 1952 and 1953, the reduction in lower altitudes was less than 60%, in higher one (above 800 m a.s.l.) more than 90%. The studies indicate that the radial growth of beech can be reduced by late frosts mainly at higher altitudes sites. In areas situated below, intensive late frosts (tmin <-3OC) in the days of or immediately after leaf unfolding, occur sporadically and slightly effect on radial growth of beech.

REFERENCES

Dittmar, C, Fricke,W & Elling, W. (2006). Impact of late frost events on radial growth of common beech in Southern Germany. Eur. J. Forest Research: 125: 249-259. Rötzer, T., Grote, R. & Pretzch H. (2004). The timing of bud burst and its effect on tree growth. Int. J. Biometeorol. 48:109-118.


82

Tree-ring records of volcanic influence on climate in the Tatra Mountains

K. Janecka, T. Biczyk, R.J. Kaczka Faculty of Earth Science, University of Silesia, Sosnowiec, Poland

Stone pine Pinus cembra L. (PICE) and Norway spruce Picea abies L. Karst (PCAB) are the two tree species, which constitute the timberline ecotone in the Tatra Mountains, Western Carpathians, however Stone pine also frequently lives in the higher elevation above timberline. Growth of both species is strongly influenced by summer temperature; therefore tree rings are reliable proxies of long-term and abrupt changes of the high-mountain climate. Among other factors, volcanic eruptions are one of the most important agents responsible for such short-lasting but significant fluctuation of global climate. Analysis of wood anatomical features such as pale rings and frost rings have proven to be useful in dendrochronology offering linkages to environmental parameters, not provided by other parameters. The proxies related to various features of tree rings: tree ring width, quantitive wood anatomy, wood density register wide spectrum of volcanic events. The study aims at assessment the main volcanic induced climate events recorded in tree-rings of PICE and PCAB by: i) identification of the volcanic records in studied features of tree rings, ii) comparison of PICE and PCAB proxies. The research was carried out in 9 sites located in the Polish Tatra Mountains, within and above timberline ecotone. 51 samples of Stone pine and 115 samples of Norway spruce were used to develop chronologies of tree ring width (TRW), wood anatomical anomalies (pale rings and frost rings) and blue intensity. Chronologies of both analysed species were compared with the information about volcanic activity (VEI, DVI, IVI) (Robock 2000) for the period 1730 - 2013. The pale rings and blue intensity measurements revel strong influence of the main stratovolcano eruptions from South and North Hemisphere (Tambora 1815, Katmai 1912, Augustine 1976, Pinatubo 1991) (Schneider et al. 2009) on the growth analysed species. Comparison between PICE and PCAB chronologies especially these of pale ring show differences of strength and timing of volcanic records. In analysed species three from four eruptions (Katmai, Augustine, Pinatubo) were archived in pale rings in the years of eruptions. The most significant influence had Katmai eruption that caused pale ring formation in 1912 (PCAB, PICE), 1913 (PICE) and frost rings formation in 1913 (PCAB). The similar results were obtained from blue intensity chronologies whereas minima of TRW chronologies reveal much lower synchronicity with volcanic eruptions.

REFERENCES

Robock A. (2000). Volcanic eruptions and climate. Reviews of Geophysics 38.2: 191-219. Schneider, D.P., Ammann, C.M., Otto‐Bliesner, B.L. & Kaufman, D.S. (2009). Climate response to large, high‐latitude and low‐latitude volcanic eruptions in the Community Climate System Model. Journal of Geophysical Research: Atmospheres (1984–2012): 114(D15).


83

The tree ring study of downy birch in Northern Europe

R.J. Kaczka1 K. Janecka1, B. Czajka1, O. Eggertsson2 1 Faculty of Earth Science, University of Silesia, Poland

2 Icelandic Forest Research, Iceland [email protected]

Downy birch (Betula pubescens Ehrh.) is one of the main native tree species in Northern Europe, it grows from Iceland and British Islands to Finland and further east in Northern Russia. Although various birch species are very common in Eurasia Downy birch is more associated with exposed habitats such as mountains and high latitudes. In Iceland the growth of Downy birch is driven by summer temperature whereas there is little known about a relationship between the populations from rest of Nord Europe and Asia. The aim of this study has been i) to define wheather the climate influences on birch growth, ii) to test the teleconnection between selected regions of Europe.

Two sites from Iceland, one from Scotland, Norway and Sweden (obtained from ITRDB) were compared. Approximately fifty trees per site were sampled; due to frequent occurrence of irregularities of rings two cores per tree were taken. Standard dendrochronological methods were used to produce and test time series of TRW. The character of the wood and abundance of missing rings create challenges related to the preparation, measuring and analysis. The visual cross-dating was essential to assemble the coherent sets of TRW series. Trees from both regions were relatively young (~ 70 – 130 years) and to enhance the climatic signal different techniques of chronology computing were tested employing ARSTAN. The dendroclimatic analyses were performed using instrumental and CRU grid data of temperature and precipitation. The pointer years and longer lasting growth changes were calculated to identify the short climatic events and influence of insect outbreaks (mainly Epinotia solandriana).


84

Dendrochronological studies of timberline changes at Babia Gora Mt., Western Carpathians

B. Czajka1, R.J. Kaczka1, A. Łajczak2 1 Faculty of Earth Sciences, University of Silesia, Sosnowiec, Poland

2 Pedagogical University, Institute of Geography, Podchorazych 2, 30-084, Cracov, Poland

Timberline, the highest located, forest related ecotone is a very sensitive element of high-mountain regions. Tree-rings are a valuable proxy of their past and present dynamics. The aim of this study is to assess the role of different natural and anthropogenic factors influencing the location and character of timberline at Babia Gora Mountain during last century. Babia Gora Mt. (1725 m a.s.l.) is the highest part of the Beskidy Mountains, located in the northern part of the Carpathian Arc. It is a single isolated massif (80 km2) with well-developed climatic-vegetation zones and an alpine timberline formed by Norway spruce (Picea abies) at an altitude of 1380 m a.s.l.

Temporal and spatial changes of the timberline were determined by means of GIS analyses of aerial photos from 1964 and 2009. According to the results, the 37 km long timberline can be divided into three types: progressive (31%), stable (61%) and regressive (8%). Seven sites were selected for detailed dendrochronological analysis of two of most frequent ones (4 sites on stable and 3 progressive). Together ~600 trees were sampled and analyzed.

The altitude of timberline rose by approximately 24 m (with the maximum of 200 m) during the analyzed 45 years. Stable timberline is localized mostly on a steep and inaccessible northern slopes. Main natural, but very space-limited factor of timberline regression is related to geomorphological processes such snow avalanches and debris flows. Most of observed advances of timberline were caused by two dominant factors – abandonment of pasturing and climate change. The average tree age at all seven sites varies from 50 to 150 years. Depending on the local history of land use (forest harvesting and pasturing) three sites are characterized by even-aged tree generations and four by complex age structure. Positive TRW response to summer temperature and negative to precipitation increases with altitude and reaches maximum values at the timberline zone. The results show that climate is the main and stable factor influencing tree growth in the timberline ecotone.


85

Tree-ring analysis of sub-fossil pine wood from the Rucianka and Józefowo raised bogs (NE Poland)

J. Barniak, M. Krąpiec Faculty of Geology, Geophysics and Environmental Protection, AGH-University of Science and

Technology, A. Mickiewicza 30 Ave., 30-059 Krakow, Poland

Well preserved in peat wood remains are valuable source of information about environmental conditions in the past. Sub-fossil pine wood from the Rucianka and Józefowo raised bogs (NE Poland), which are closely located to each other (25km), were dendrochronologicaly investigated. In total, 300 samples were collected, respectively 200 pine discs from the Rucianka bog and 100 pine samples from the Józefowo bog. Samples were collected mainly from material gathered on a wood heaps, stretching along a harvesting field. The standard dendrochronological analysis, applied for sub-fossil wood from peat bogs, was used. Tree-ring width measurements were carried out using DENDROLAB 1.0 – a standard dendrochronological equipment set. At least two radii from each sample were measured. Correlation of individual tree-ring width sequences and visual comparing of dendrograms for each tree allowed to identify groups of samples of the same age. Samples for radiocarbon dating were selected from each chronology, which were constructed for each group of wood of the same age. Based on radiocarbon analysis and wiggle-matching method floating chronologies were dated. The local floating standards cover the period ca. 990-170 cal. BC. Germination and dying-off phases (GDO), related with wetter climate periods, were determined to ca. 850 cal. BC, 740-700 cal. BC, 520 cal. BC, 460 cal. BC. The narrow-ringed wood zones reflected unfavorable habitat conditions and are connected with higher water level at the peat bog. Characteristic narrow-ringed zones are periodically visible in samples as well as at the end of pines life. In investigated sub-fossil pine wood from both bogs the fire scars, reaction wood and traces of insects feeding were observed.


86

The effect of black cherry understory on growth of scots pine

Ł. Ludwisiak, S. Bijak Laboratory of Dendrometry and Forest productivity, Warsaw University of Life Sciences-SGGW,

Poland

Black cherry (Prunus serotina) is a north American species that in the middle of 20th century was massively introduced in Poland into pure Scots pine (Pinus sylvestris) forests to improve site quality, pine growth conditions and fire protection. However, the species spread out rapidly, causing serious disruptions in forestry and nature conservation. Currently, because of its high ability to propagate P. serotina is considered as an invasive and hence dangerous species. Objective of the study was to compare the radial growth of P. serotina and P. sylvestris growing together to assess the potential level of concurrence between these species. For comparison we also studied radial growth pattern of Scots pine growing without P. serotina understory. Material was gathered in three pairs of Scots pine stands. Each pair consisted of one with extensive abundance of black cherry in the understory and other without P serotina. Analyzed stands characterized with similar age, soil conditions and origin. Twenty increment cores per species per site were collected and tree-ring widths were measured. Standard chronologies were built and growth patterns compared. Additionally we analyzed the influence of extreme weather conditions on radial growth of both investigated species.


87

Detecting a buffer zone of a mire by growth release of pines in Estonia

A. Läänelaid, K. Sohar, A. Kull Department of Geography, Institute of Ecology and Earth Sciences, University of Tartu,

Tartu, Estonia

In a landscape under anthropogenic pressure many peatland areas have been meliorated in Estonia, either for peat extraction or for forestry or agriculture purposes. The remained mires often have draining ditches in their peripheral area, affecting the hydrology and vegetation of the mire. The main objective of this study is to assess the effect of drainage to radial growth of trees growing there, to determine the width of necessary buffer zone from the ditch for preserving the natural part of the mire. Altogether, 20 mires all over Estonia were investigated. Here we show study from Tellissaare Bog as an example. In the bog a transect perpendicular to the drainage ditch towards the centre of the mire massif was established. Starting from the ditch, 7 study plots were established at increasing distances along the transect. 12 Scots pines (Pinus sylvestris L.) were bored at each plot parallel to the ditch within a 2-meter zone in both sides from the transect. Tree-ring width measurements in opposite radii were averaged, the juvenile growth rings were removed, and an average tree-ring width series was composed for each plot. Growth changes (releases) in plot chronologies were detected using Nowacki and Abrams (1997) method, where relative change between median of 7 preceding and median of 10 subsequent years’ increment was calculated. The 6th plot in the middle of bog massif was assumed to have no anthropogenic influence and was used as reference of bog pines’ response to climate.

Preliminary results show a certain time lag between the recorded drainage time and detected maximum growth release. The drainage effect fades within a hundred metres from the ditch. This can be considered the required buffer zone for mire protection. The radial growth of pines in the middle of untouched bog is positively influenced by winter (preceding December) and spring (April) precipitation while monthly temperature variations have no significant effect.

REFERENCES

Nowacki, GJ, Abrams, MD. (1997). Radial-growth averaging criteria for reconstructing disturbance histories from presettlement-origin oaks. Ecological Monographs 67: 225–249.


88

Effect of climatic factors on height increment of Scots pine in Latvia

R. Matisons, B. Džeriņa, J. Kalniņš, Ā. Jansons LSFRI “Silava”, Rigas str. 111, Salaspils, Latvia, LV2169

Scots pine is a widespread and common species in Central and Northern Europe, which has high ecological and economic importance. For this reason, formation of wood increment (tree-ring width and other tree-ring proxies) of Scots pine in relation to various environmental factors has been intensively studied throughout the Europe. Nevertheless, height growth, a parameter, which can be directly linked with productivity of growth, has been poorly studied, likely due to laborious gathering of data. Considering that climate if one of the main environmental factors, which determine tree growth, in this study we analysed climatic forcing of height increment of Scots pine in Latvia. Two naturally regenerated sites of Scots pine (~ 100 years old) located in national forest research stations in western and eastern regions of Latvia were sampled. In each site, 20 dominant pines were selected and felled; cutting was done as close as possible to the base of stem. Felled trees were limbed and stems were cut tangentially (~ 3 –5 cm from the pith) to expose whorls (knots). Height of each whorl was measured with precision of 0.5 cm. Three stem disks, containing whorls from various heights (~ 1.3, 10 and 18 m) were collected from each stem for dating purposes. Annual height increments were calculated and dated using tree-ring analysis. Time-series of height increment were crossdated and their quality was once again checked by graphical inspection and statistically (COFECHA). Similarity of height increment patterns was assessed by PCA. Residual chronologies were produced for each site. The effect of climatic factors (mean monthly temperature and precipitation sums) was determined by correlation and response function analysis for the whole period and by 50-year moving intervals using DendroCLIM2002 program. Measurement time-series covered period of 1906–2012 and 1927–2013 in western and eastern region of Latvia, respectively. Crossdating was rather complicated; however, 70 % of measured time-series were used for the analysis. According to PCA, there were obvious differences in height growth pattern of pine between sites, although GLK was 0.65. Sets of climatic factors significant for height increment of pine differed between regions; three factors were significant in western and 10 factors were significant in eastern region. Temperature in April and June of the year preceding growth significantly affected height growth of pine in western region of Latvia. Temperature in October of year preceding growth and precipitation in August and November in previous year and in June of the year of growth were the main factors affecting height growth of pine in eastern region. Changes in sets of significant climatic factors were observed. In western region of Latvia, temperature in April, July and October of the year preceding growth has lost their significance around mid-part of 20th century; however, none of tested factors has clearly become limiting during analysed period. In eastern region of Latvia, June, July, November and December precipitation of the year preceding growth and temperature of November two years before growth has lost significance, while temperature in October in year preceding growth had become the main limiting factor (showed the strongest effect). Thus our result suggest, that climatic factors significantly affected height growth of Scots pine in mid-part of its distribution area. This study was founded by Forest Competence Centre (ERAF) project «Methods and technologies for increasing forest capital value» (No. L-KC-11-0004).


89

Growth response of mountain spruce (Picea abies (L.) Karst.) to extreme climatic and pollution stress event

M. Vejpustková1, A. Zeidler2, T. Čihák1, V. Šrámek1 1 Forestry and Game Management Research Institute, Strnady, Czech Republic

2 Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Czech Republic

Climatic extremes are expected to increase in frequency and magnitude as a consequence of global warming. To predict future performance of forest ecosystems, processes behind tree response to extreme climatic events must be examined. The main objective of presented study is to evaluate retrospectively growth response of spruce to extreme climatic and pollution stress during the winter 1995/96 in the Ore Mountains (Czech Republic) using methods of dendrochronology and wood anatomy analysis, and to evaluate the reliability of radial growth as a stress indicator. The study is based on permanent monitoring plots established in 1996 within the young spruce stands (age of 20 – 40 years) covering the gradient of forest damage in the Ore Mountains. In 2013 about 500 increment cores were sampled at ten plots. The differences in growth response between the plots of different damage level were investigated. The extremities in tree-ring formation - abrupt growth decrease, occurrence of missing or incomplete (wedging) rings, presence of compression wood, wound or discoloured tissues and increase in resin ducts - served as the stress indicators. The study took advantage of the data from annual assessment of tree vitality, tree nutrition and pollution load within the plots in the period 1996 - 2013. Reliability of radial growth as a stress indicator was evaluated in relation to the routinely assessed parameters such as defoliation, number of needle year classes and the length of annual shoots.


90

Influence of atmospheric pollution on climate response of Poincianella pluviosa var. peltophoroides and Bignonia pentaphylla

trees in Brazil

M. Peres Chagas, M. Tomazello Filho, A.P. Radaeli Neto, A. Venegas González University of São Paulo, Piracicaba, Brazil

The response functions are widely used in dendroclimatology to describe the relationship between climate and tree growth. In this study, Poincianella pluviosa var. peltophoroides (Fabaceae-Caesalpinaceae) and Bignonia pentaphylla (Bignoniaceae) trees were selected with the aim of evaluate the influence of air pollution by the application of tree-rings analysis. The study area is located at Paulínia, São Paulo State, Brazil and it’s environmental pollution history of anthropogenic origin was provided by the Environmental Sanitation Technological Center (CETESB) and by recent studies of environmental monitoring found in the specialized literature. Three other areas in the municipality of Paulínia and Piracicaba were also selected, establishing an environmental gradient of anthropogenic pressure within 10, 15 and 60 km distance. Tree-ring chronologies of the 2 tree-species and meteorological data (monthly mean temperature and accumulated precipitation) of the last 54 years were used in correlation analysis performed by Response Function Analysis (RESPO). The results indicated that, for the both species, the climate responses observed for trees growing under lower anthropogenic pressure (60 km) is consistent with the literature for this specific location, with climatic factors exerting positive and negative effects on tree growth during spring/summer (November-January) and autumn/winter (April-June) seasons, respectively. For the trees growing closer to the stationary and mobile sources of air pollution, an absence of climate response were observed indicating that this stress factor may be influencing the tree growth. In this work, that hypothesis is discussed with the obtained values of radial increment, tree rings width time series and mean sensitivity.


91

Climate sensitivity of Fagus sylvatica L. based on tree-ring analyses in peripheral populations in Spain

L. Akhmetzyanov1, I. Dorado Liñán2, G. Gea-Izquierdo3, E. Gutiérrez4, A. Menzel2,5 1 Chair of Forest Ecology and Forest Management, Wageningen University, Netherlands

2 Chair of Ecoclimatology, Technische Universität München, Freising, Germany 3 CEREGE UMR, CNRS/Aix-Marseille Université. Marseille, France

4 Ecology Department, University of Barcelona, Barcelona, Spain 5 Institute for Advanced Study, Technische Universität München, Garching, Germany

Climate change projections for Europe suggest a temperature increase of 4 - 5° C for the 21st century. Global warming trends will definitely affect temperate tree species, especially those populations growing at their tolerance limits. In this context, peripheral populations are more prone to be imperiled by external factors than more central or continuous populations. European beech (Fagus sylvatica L.) forests at the Iberian Peninsula are a clear example of temperate species at the rear edge of a large distribution area, with several geographically isolated populations. In addition to their value for conservation purposes, increased knowledge on the response of such peripheral forests to climate change is important for predicting future distribution of the European beech and choosing adequate forest management facilities. Some pioneer studies on the well-known European beech forest of Montseny (Barcelona) revealed that tree-growth is strongly limited by drought and beech forest is being progressively replaced by Mediterranean holm oak forest (Peñuelas et al. 2007). In order to gain deeper knowledge on the response of marginal European beech populations to climate change, we analyze four isolated forests at the Iberian Peninsula: two in the central part (Montejo and Tejera Negra) and other two at the North-East (Montseny and Els Ports). Three out of the four sites are unexplored in terms of tree-growth and the work presented here represents the first assessment of the climate-growth relationships at these forests. Summer precipitation was unequivocally identified as the main limiting factors for tree-growth in the beech forest of Montejo, Tejera Negra and Els Ports. At the same time, summer temperature also showed significant effect on beech stands in Montejo and Els Ports. While these relationships were stable, a decline in tree sensitivity to climate was detected in beech forest from Montseny.

REFERENCES

Peñuelas, J. et al. (2007). Migration, invasion and decline: changes in recruitment and forest structure in a warming-linked shift of European beech forest in Catalonia (NE Spain). Ecography, 30: 829–837.


92

Climate drivers of beech growth at marginal sites across Mediterranean

K. Chen1, I. Dorado Liñán1, L. Akhmetzyanov1, A. Menzel1,2 1 Technische Universität München, Chair of Ecoclimatology, Freising, Germany

2 Technische Universität München, Institute for Advanced Study, Garching, Germany

The Mediterranean region has been described as a climate change hotspot, where climate shifts have already taken place. European beech (Fagus sylvatica L.) represents one of the most important European forest tree species and the study of climate-growth relationships could provide relevant information for projections of future species distribution and forest management strategies. In this study, nine European beech stands growing under xeric conditions were selected at the rear edges of the species distribution in Spain, Italy and Bulgaria, across an east – west transect at the Mediterranean Basin (MB). Pearson correlation and Principle Component Analysis (PCA) were used to explore the influence of temperature and precipitation on tree growth to identify spatial patterns of climate influence and to assess the effect of the North Atlantic Oscillation (NAO). The results reveal that stands located at the western Mediterranean are limited by the combined influences of summer temperature and precipitation while stands located in central and eastern Mediterranean are limited mainly by summer temperature. Winter NAO exerts a significant negative influence on sites located in western, central and eastern MB. However, the significance of NAO influence is generally decreasing from western to eastern MB.


93

Climate-growth relationships of Fagus sylvatica and Pinus sylvestris along an altitudinal gradient in their southern distribution limits

(Moncayo Natural Park, Spain)

E. Martínez del Castillo1, K. Novak1, R. Serrano1, E. Tejedor1, P. Prislan2, J. Gričar3, L.A. Longares1, M.A. Saz1, K. Čufar2, M. de Luis1

1 University of Zaragoza, Dept. Geografía y O.T. C/ Pedro Cerbuna 12, 50009 Zaragoza, Spain 2 University of Ljubljana, Biotechnical Faculty, Department of Wood Science and Technology,

Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia 3 Slovenian Forestry Institute, Večna pot 2, SI-1000 Ljubljana, Slovenia

Moncayo Natural Park represents one of the southern distribution limits for Fagus sylvatica and Pinus sylvestris in Europe. Trees growing at their distribution limits are considered to be more sensitive to climatic factors and are therefore especially suitable for ecological and climatological studies. Since the species are distributed along the altitudinal gradient, elevation can be used as a factor to obtain additional information about the climate-growth relationships of Fagus sylvatica and Pinus sylvestris. To determine and analyse the climatic variables which are affecting radial growth at the above mentioned site, 15 chronologies of Fagus sylvatica, 8 chronologies of Pinus sylvestris and 3 additional chronologies of Pinus uncinata were collected at different elevations (between 1020 and 1900 m a.s.l.). Principal component analysis (PCA) of tree-ring chronologies was performed to highlight the differences in radial growth among the sites and to form groups with similar growth patterns. Chronologies were divided into four groups: Fagus sylvatica from low and high elevation, and Pinus sp. from low and high elevation. Daily climatic data for the period between 1950 and 2010 were obtained from SPAIN02 database (Herrera et al., 2012). Besides, for each sampling point, an independent climatic series was reconstructed, using data from climate stations placed at different altitudes along Moncayo Mountain and the surroundings. Twenty-four climate indexes were calculated with help of RClimDex software. PCA eigenvectors were used to identify differences in climate–growth relationship among the different chronologies and the obtained groups. Thus, a correlation function analysis was performed using the DendroClim2002 programme (Biondi and Waikul 2004). The results suggest that the growth of the genera Fagus and Pinus is driven by different climatic factors and that the climate-growth relationship changes along the elevation gradient. Moreover, it was shown that the use of reconstructed climatic series improves the analysis of climate-growth relationships.

REFERENCES

Biondi F, Waikul K (2004). DENDROCLIM2002: A C++ Program for statistical calibration of climate signals in tree-ring chronologies. Computers & Geosciences 30: 303–311. doi:10.1016/j.cageo.2003.11.004 Herrera, S. Gutiérrez, J.M Ancell, R. Pons, M.R. Frías M.D. & Fernández, J. (2012). Development and analysis of a 50 year high-resolution daily gridded precipitation dataset over Spain (Spain02). International Journal of Climatology 32: 74-85 doi: 10.1002/joc.2256.


94

Study of the record of meteorological data in the Pinus pinaster wood growing in Portugal

J. Lousada1, M. Gaspar1, M. Silva1, C. Besson2 1 Centre for the Research and Technology of Agro-Environmental and Biological Sciences, CITAB,

University of Trás-os-Montes and Alto Douro, UTAD, Quinta de Prados, 5000-801 Vila Real, Portugal, www.utad.pt

2 Instituto Dom Luis, Depa. Física da Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal

Under the Project PTDC/AGR-CFL/99614/2008 “Phenotypic plasticity of maritime pine to climate change” we carried out a task entitled “Dendrochronology: Evaluation of tree-ring width and wood density components”, where was assessed the impact of climatic parameters in ring width and wood density. The field material was collected in 6 representative sites of the species in Portugal. 10 trees with minimum age of 40 years were sampled at each site. From each tree it was extracted a core sample, which were submitted to an microdensitometric analysis by X-rays, for obtaining the density components and annual growth per tree. These components were crossed with meteorological data (precipitation and temperature) of each site in order to assess what extent these meteorological parameters affecting the growth and the features of wood. Are presented data regarding Lezírias site. Regarding the precipitation effect, it was concluded that is what occurs in winter and spring that will regulate the ring width. On the other hand the precipitation that occur in the summer has a very small influence on the width of the latewood. Regarding the effect of precipitation in the wood density, it was found that the precipitation that occurs in winter and spring does not affect the earlywood density, but it will regulate the latewood density. The precipitation observed in the summer has no influence on the latewood density. Regarding the effect of temperature, it always showed very modest, both in ring width as in wood density features.


95

Climate sensitivity of European black pine at the treeline in the Central Apennines, Italy

A. Piermattei, M. Garbarino, C. Urbinati Università Politecnica delle Marche, Ancona, Italy

In five sites of the central limestone Apennines above the treeline located along a latitudinal gradient (over 300 km), we have studied a recent encroachment of Pinus nigra (European black pine) started 30-40 years ago at unusual high altitude (over 2000 m a.s.l.). This complex process is controlled by synergic factors such as decreased grazing pressure, climate change, topography, seed availability, dispersion and germination efficiency, etc. In four of the study sites the encroached trees and seedlings are produced by nearby black pine treeline stands planted 40-60 years ago scarcely or not subjected to targeted silvicultural practices. Main goal of the project is to disentangle and assess the influence of climate on the spatio-temporal dynamics of the encroaching pines. One important step of this analysis is to calibrate the growth trends and climate sensitivity of pioneer and planted individuals of black pine. We sampled a total of 906 encroached individuals above the current treeline and more than 80 forest border trees, 20 from each plantation. We collected one basal core from 641 pioneering pines and two cores at breast height from the plantation trees. Tree-ring width measurements at 0.01 mm accuracy were provided for all cores by LINTAB and WinTSAP (Rinntech) and crossdated with COFECHA. We built four black pine site chronologies divided in pioneer and planted trees and we compared them to reference master chronologies available on the web. In all the cores we also measured the frequency of intra annual density fluctuations (IADFs). Climate-growth correlations were calculated with DENDROCLIM2002 setup for 1000 replications to compute the bootstrapped correlations and using detrended series and monthly maximum, minimum and mean temperatures and total precipitation data obtained from a 0.5 × 0.5 degree spatial grid (http://climexp.knmi.nl/). We found a good synchronization of encroached trees with old trees from pine plantations. However, the pioneer pines have a stationary growth, compared to the planted pines that show a negative trend in the last fifteen years, probably due to the competition effects or climatic stress. The black pine is particularly sensitive to maximum temperatures at the beginning of the growing season. Younger pioneering trees are more sensitive to climate influence especially in relation to the frequency of IADFs. These were mainly formed in mid-late summer with highest frequency peaks between 2003 and 2004. Whit this work we highlighted a recolonization process above the current treeline, that is induced by land use change, where climate seems to be an important driver. The difference sensitivity to climate displayed by planted and encroached trees of Pinus nigra, that probably have the same genetic provenance in each site, suggests a possible adaptation developed by some trees to changed climatic conditions.


96

Drought metrics and tree growth: matches, mismatches, and some implications for modeling continental-scale drought

U. Bhuyan1, C. Zang1, A. Menzel1,2 1 Chair of Ecoclimatology, Technische Universiät München, Freising, Germany

2 Institute for Advanced Study, Technische Universiät München, Garching, Germany

Tree-ring width is an appropriate and often used proxy for reconstructing past climate conditions. They are also used to study extreme weather events. It has been well documented that climatic conditions influence the growth of trees. Similarly extreme climatic conditions like drought are also seen to influence tree growth, yet it remains a challenge to choose appropriate descriptors of drought to match the spatio-temporal characteristics of climate information encaptured in tree-ring networks. The goal of this study is to assess the connection between primary climatic variables and exisiting drought indices and the growth of different tree species during a drought event. For this purpose, we analyse the growth response of tree rings to monthly climate conditions obtained from the CRU TS3.21 data set back to 1901 upto present. The tree-ring network consists of 992 site chronologies consisting of 36 tree species distributed over Europe (Babst et al. 2013). The key aims are (a) to examine the relationship between observed tree growth at the 992 distributed tree-ring sites and climatic parameters like temperature, precipitation, potential evapotranspiration, cloud cover, vapour pressure and commonly used drought indices (PDSI, SPEI, SPI, DMI) (b) To assess these principal climatic drivers of continental-scale (Europe) drought and isolate spatiotemporal patterns and species traits. These efforts lead to the description of (mis)matches between the spatio-temporal characteristics of tree-ring network data and the employed drought descriptors, and the implications for dendroclimatic calibration and drought reconstruction performance, as well as for the relation of these drought descriptors to relevant ecosystem-level responses.

REFERENCES

Babst, F., Poulter, B., Trouet, V., Tan, K., Neuwirth, B., Wilson, R., Carrer, M., Grabner, M., Tegel, W., Levanic, T., Panayotov, M., Urbinati, C., Bouriaud, O., Ciais, P. and Frank, D. (2013). Site- and species-specific responses of forest growth to climate across the European continent. Global Ecology and Biogeography, 22: 706–717.


97

Growth responses to decadal climate variations over the last 250 years pose issues on future performance of Norway spruce, silver fir and

European beech. Evidences from a mixed old-growth forest in Bosnia and Herzegovina

D. Castagneri1, P. Nola2, R. Motta3, M. Carrer1 1 Dept. TeSAF, University of Padua, Legnaro (PD), Italy

2 Dept. Earth and Envir. Science, University of Pavia, Pavia, Italy 3 Dept. DISAFA, University of Turin, Grugliasco (TO), Italy

Over the last decades, most dendrochronological research has been conducted on trees growing near their environmental limits, as they have an evident response to climate. However, processes observed in such conditions can only be barely indicative of climate change influence on most forested areas, which do not lie at the altitudinal or latitudinal limits of species distributions. Few studies have investigated species different response to climate in mesic forests, especially in South-Eastern Europe. In the forest reserve of Lom, in Bosnia and Herzegovina, we had the opportunity to study three co-occurring species (silver fir, Norway spruce, European beech) in an old-growth mesic forest characterized by reduced human and natural disturbances. We evaluated species growth response to decadal climate variations over about 250 years. Covering an area of approximately one squared kilometre, we sampled 34 Norway spruce, 35 silver fir and 47 European beech trees among dominant and co-dominant individuals (two cores per tree). Raw ring width series were detrended using 200 years cubic splines (50% cutoff). Mean species chronologies, as well as climate series, were then processed with a low-pass filter (20 years cubic spline, 50% cutoff) to identify decadal variations. Divergent responses to climate have been detected among species: spruce was mostly negatively affected by decadal variations in summer temperature (r=-0.71) whereas summer precipitation benefited fir growth (r=0.48), probably reducing high temperature stress. Beech showed a peculiar delayed response, and protracted drought periods led to severe growth reductions (r=-0.57 with previous-five year’s summer temperature). Recent growth trends agreed to previous patterns. Despite increased temperature over the last three decades, fir did not experience any evident variation. Good performance of this species within the global warming context has been reported for Central Europe over the last years. On the other hand, negative trends in spruce and beech productivity, related to increased temperature, should be considered in management strategies and CO2 carbon sink estimates in the future.


98

Dendroclimatic and dendroecological potencial of a new tree-ring database along the Iberian Range

E. Tejedor1, M. De Luis1, J.M. Cuadrat1, K. Novak1, R. Serrano1, E. Martínez1, L. A. Longares1, M.A. Saz1

1 Department of Geography and Spatial Planning Environmental Science Institute of the University of Zaragoza (IUCA)

The fifth IPCC report on climate change states that the warming of the climate system is unequivocal and that temperatures have increased in an unprecedented way in decades, even millennia. Different scenarios show increases in temperature and recurrence of extreme weather events, such as droughts. Therefore, it is particularly important to study the evolution of the past climate in order to generate climatic future scenarios with better precision. In this communication we present the dendroclimatic and dendroecological potencial for a climatic reconstruction of the Iberian Range with a new dendrocronological database. The recent trend of dendroclimatic and dendroecological studies is the use of a greater number of samples of growth in order to improve the standardization phase and thereby the conservation of the medium and low frequency signal. The new multi-species tree-ring database is composed of a total of 561 samples of Pinus uncinata, Pinus sylvestris, Pinus halepensis, Pinus nigra and Pinus pinaster from the ITRDB (25.84%) of projects developed in the years 80-90 from the IPE-CSIC (17.29%) and the extracted by the signatories of the communication between 2012 and 2013 (56.86%). Due to the different time spans covered by the tree-ring series, different principal component analyses (PCA) were performed for each of the standardization methods used (Splines100, Splines300, Regional Curve Standardization). The samples have been grouped into different chronologies based on the PCA. Then, in order to know the relation between climate and growth, the chronologies have been calibrated with the climatic information coming from different climatic databases such as CRU TS 3.1. or SPAIN02. The results show the potential of this multi-species dendrochronological collection for the reconstruction of the summer precipitation, but also the limitations inherent to the standardization and the absence of instrumental climate information in height. This work has been conducted within the project 'Characterization of the climate of northeastern Spain from the sixteenth century, integrated analysis through information multiproxy and instrumental (CGL2011-28255)´.

REFERENCES

Herrera, S. et al. (2012). Development and snalysis of a 50-year high-resolution daily gridded precipitation dataset over Spain (Spain02). International Journal of Climatology 32: 74-85: doi: 10.1002/joc.2256. Mitchell, T.D. et al. (2004). A comprehesive set of high-resolution grids of monthly climate for Europe and the globe: the observed record (1901-2000) and 16 scenarios (2001-2100). Tyndall Center Working Paper 55: 1-30.


99

Using Deuterium to trace movement and storage of water in Eucalypt trees (Richmond, Australia)

Kerstin Treydte1,2, Tomasz Wyczesany3, Derek Eamus3, Sebastian Pfautsch2 1Swiss Federal Research Institute WSL, Zuercher Strasse 111, 8903 Birmensdorf, Switzerland

2Hawkesbury Institute for the Environment, University of Western Sydney, Richmond, 2753 NSW, Australia

3Plant Functional Biology and Climate Change Cluster, University of Technology, Sydney, 2007 NSW, Australia

The capacity of trees to release water from storage compartments into the transpiration stream can mitigate damage to hydraulic functioning. However, the location and magnitude of these ‘mobile’ water sources still remains a topic of research. We conducted an experiment on two tree species that naturally grow in regions of high (Eucalyptus tereticornis) and low (E. sideroxylon) rates of annual precipitation. Deuterium enriched water (1350 ‰ label strength) was introduced into the transpiration stream of three trees per species for four consecutive days. Then the trees were felled and samples of all woody tissues were collected from different heights and positions of the stem. Water was extracted from all samples and the isotopic composition measured. Our results indicate that vertical water transport was more efficient in E. tereticornis while radial water transport was more pronounced in E. sideroxylon. The latter has a larger relative stem water storage capacity than E. tereticornis. This is probably related to differences in the hydraulic architecture across the two species, with a larger resistance of the xylem to cavitation in E. sideroxylon due to smaller vessel diameters, resulting in the trade-off of slower growth and lower tree height. Generally water in the phloem is a larger source for capacitance than water in the heartwood. Further integrative data analyses will improve our understanding of the mechanisms that allow trees to survive and adapt to drought.


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