soil organic matter dynamics in mountainous environments
TRANSCRIPT
Soil organic matter dynamics in
mountainous environments under a changing climate -
Concepts and methodology
Frank Hagedorn
and Stephan Zimmermann
Swiss Federal Institute for Forest, Snow and Landscape Research (WSL)
Birmensdorf (CH)
outli
ne
1. Why to look at feedbacks climate change - SOM?
2. Experimental approaches
3. Case study: Treelines in the Ural mountains
4. Case study: Alpine treeline in Stillberg (Switzerland)
5. Learning from the global C distribution and past
outli
ne
Batjes, European Journal of Soil Science, 47, 151-163, 1996
back
grou
ndFeedbacks: Warming C storage
SOM-decay + _atmospheric
CO2
Warming
Growth
SOMincrease
C storage
Feed
back
s: S
OM
cl
imat
eWill changes in soil organic carbon act as a positive
or negative feedback on global warming?
Miko U.F. KirschbaumBiogeochemistry 48, 21-51, 2000
LGM: Last Glacial Maximum
Feed
back
s: S
OM
cl
imat
e
Tem
pera
ture
dep
ende
ncy
Growth
SOM
increase
Warming
SOM-decay+
_
atmospheric
CO2
C storage
)(2 )/( 12
10
110TTkkQ −=
Van't Hoff, 1898: Change of reaction rates across 10K
Exp
erim
enta
l app
roac
hes
1. Laboratory incubations
2. Soil warming studies
3. Altitudinal/latitudinal transects
Labo
rato
ry in
cuba
tion
CO2 -Production
DOC-leaching
Labo
rato
ry in
cuba
tion
From Reichstein et al. (2000): Soil Biol. Biochem. 32, 947-958
Temperature drives soil respiration
Labo
rato
ry in
cuba
tion
Q10 -
Temperature dependent
Ref.: Kirschbaum (1995): Soil Biol. Biochem. 27, 753-760Mikan et al. (2002): Soil Biol. Biochem. 34, 1785-1795
Sum
mar
y la
bora
tory
incu
batio
n
• Temperature sensitivity greater at lower T
Limitations
• More rapid losses of labile SOM at high T
• Disturbance, no input
Soi
l war
min
g st
udie
sExperimental Warming
Greenhouse-WarmingVal Bercla, Switzerland
Marion et al., Global Change Biology 3 (Suppl.1), 20-32, 1997Hollister and Webber, Global Change Biology 6, 835-842, 2000
Soi
l war
min
g st
udie
s
UV-Lamps
Problems: Decreasing air humidityNon-uniform heating
Soi
l war
min
g st
udie
s
Soil Disturbance
Non-uniform heating
Heating cables
Problems
Soi
l war
min
g st
udie
sWarming: increased C losses
Ref.: Melillo et al. (2002): Science 298, 2173-2176
Soi
l war
min
g st
udie
sWarming: increased C losses
Ref.: Melillo et al. (2002): Science 298, 2173-2176
Sum
mar
y so
il w
arm
ing
stud
ies Experimental warming
• Warming = Drying
• Uneven warming: C fluxes respond differently
• Response time dependent
Alti
tudi
nal t
rans
ects
Maly Iremel, Southern-Ural
Altitudinal transect
Alti
tudi
nal t
rans
ects
Where to look?
1.
Sensitive region
2.
Low anthropogenic influence
3.
Large areas
Alti
tudi
nal t
rans
ects
http://arctic.atmos.uiuc.edu/
Summer Winter
Global Warming -
Greater warming in winter
Alti
tudi
nal t
rans
ects
Treeline is limited by summer temperature
Ref.: Körner & Paulsen (2004): Journal of Biogeography 31, 713-732
Alti
tudi
nal t
rans
ects
Study Area -
Treeline in the Ural mountains
Alti
tudi
nal t
rans
ects
1999(Moiseev, Shiyatov, 2003)
1976
1929Rising treelines
Alti
tudi
nal t
rans
ects
1929
1999
Rising treelines
Alti
tudi
nal t
rans
ects
Northern treeline
Alti
tudi
nal t
rans
ects
-25
-20
-15
-10
-10
-5
0
5
10
5
10
15
20
1850 1900 1950 2000-10
-5
0
5
April
January
Mon
thly
Mea
n Te
mpe
ratu
re (°
C)
October
July
+3.6°C
+4.0°C
+1.4°C
+0°C
Year
South-UralTaganai,1100 mData from Fomin, Moiseev
Sum
mar
y al
titud
inal
tran
sect
s 1.
Treeline sensitive to temperature
2.
Large scale changes of treelines in remote regions
3.
Warming particular in winter (?)
Cas
e st
udy
Ura
lEarly Response Areas for Climate Change in Eurasia -
Spatio-Temporal Dynamics of the Upper Tree-line in the Ural
Mountains and Implications for Carbon Sequestration
IPAE, USFEU Ekaterinburg
SB RAS Krasnojarsk
ETH Zürich
Uni Halle
WSL Birmensdorf
EU-INTAS
Diploma thesis of Adrian Kammer under the supervision of Dr. Frank Hagedorn, WSL Birmensdorf
Cas
e st
udy
Ura
l
Maly Iremel, Southern-Ural
Altitudinal Gradient: ‚Space for time and climatic change‘
Cas
e st
udy
Ura
l
Treeline (1360m.a.s.l.)
3km
Forest (1260m.a.s.l.)
Mali Iremel (1449m.a.s.l)
Altitudinal Gradient
∂
0.3K
Cas
e st
udy
Ura
lC-pool estimates
Cas
e st
udy
Ura
l
Devy, Mazepa, Hagedorn, Rigling unpublished data
C-pool estimates: C-Allocation
Cas
e st
udy
Ura
l
Maly Iremel, Southern-Ural
Transect: ‚Space for time and climate change‘C-pools and productivity
Cas
e st
udy
Ura
l
1. Greater C-Input through more biomass
(above-ground: 180 vs. 60 g C m-2y-1)
2. Greater decomposition through warming ?
Rising treeline and soil carbon: mechanisms
Cas
e st
udy
Ura
l
01.01.2004 01.07.2004 01.01.2005 01.07.2005
-20
-15
-10
-5
0
5
10
15
Tundra 1350 m Forest 1250 m
Air
Tem
pera
ture
(°C
)
Micro climate: air temperature
Cas
e st
udy
Ura
l
01.01.2004 01.07.2004 01.01.2005 01.07.2005
-20
-15
-10
-5
0
5
10
15
-20
-15
-10
-5
0
5
10
15
Tundra 1350 m Forest 1250 m
Soil
Air
Tem
pera
ture
(°C
)
Micro climate: soil temperature
Cas
e st
udy
Ura
l
1360 m
1300 m
Winter climate
Cas
e st
udy
Ura
l
1200
1250
1300
1350
1400
1450
0 20 40 60 80 100 -8 -6 -4 -2 0 2Soil
Wintertemperature (°C)
Snow height (cm)
Alti
tude
(m.a
.s.l.
) Treeline
Winter climate: Snow height and temperature
Cas
e st
udy
Ura
l
Sampling: soil C pools
• 3 altitudes
•4 trees
•2 profiles under trees and
‚open‘ land
• L, F, H, 0-7cm, 7-25cm, 25-C
• additional topsoil sampling
• areal and volume based sampling
Cas
e st
udy
Ura
l
Soils: Cambisols
Tundra 1360 m a.s.l.
Forest 1260 m a.s.l.
Cas
e st
udy
Ura
lAltitudinal transect Ural: Soil profiles
Cas
e st
udy
Ura
lAltitudinal transect Ural: Soil C pools
Cas
e st
udy
Ura
lAltitudinal transect Ural: Soil C pools
Cas
e st
udy
Ura
l
Kammer, Hagedorn unpublished data
Altitudinal transect Ural: Soil C-Pools
Maly Iremel: Southern-Ural
Cas
e st
udy
Ura
l
Kammer, Hagedorn unpublished data
Altitudinal transect Ural: Soil C-Pools and producitivity
Maly Iremel: Southern-Ural
Cas
e st
udy
Ura
lAltitudinal transect Ural:SOM quality changes from tundra to forest
Cas
e st
udy
Ura
lAltitudinal transect Ural:SOM quality changes from tundra to forest
Cas
e st
udy
Ura
l
1. Increasing biomass: 15 tC/ha 75 tC/ha
2. Tripling of litter input
3. 20-40%-increase of soil C pool + 20-40 t C ha-1
4. SOM quality increases
Rising treelines and C pools
SOM <–> climate change
Cas
e st
udy
Ura
lC-Mineralisation (SOM CO2)
Cas
e st
udy
Ura
lC-Mineralisation (SOM CO2)
Cas
e st
udy
Ura
lIn situ decomposition (litter bags)
Cas
e st
udy
Ura
lAnnual C mineralization
Modelling with soil temperatures and SOM pools ICBM (Andrén & Kätterer, 1997)
Cas
e st
udy
Ura
lAnnual C in-
and outputs
Cas
e st
udy
Ura
l
Rising treelines
Greater decomposition
More biomass (15 75 t C ha-1)
Better Decomposability
Warmer microclimate
Greater litter input
Faster C-turnover compensated for greater C inputsHow does it affect N-cycling?
Summary
Cas
e st
udy
Ura
lN-Mineralisation
Cas
e st
udy
Ura
l
Warming
Precipitation1
Soil temperature
Snow cover
SOM turnover
Microbial activity
Plant (Tree)-
growth
N availability
Feedbacks: Winterwarming -
Rising Treeline
1Devi et al., Global Change Biology 14, 1581-1591, 2008
Cas
e st
udy
Ura
l
SOM <-> climate change: Summary
Climatic change likely affects C in-
and outputs in similar ways
Total SOM pool (=C sink) remains unchanged
SOM turnover increases
Cas
e st
udy
Ura
l
M. Bauer, P. Egli, T. Handa, S. Hättenschwiler, J. Hutzler, T. Hollmann, A. Kammer, R. Köchli,
Ch. Körner, W. Landolt, P. Moiseev, A. Rigling, M. Saurer, R. Siegwolf, D. Spinnler, D.
Tarjan, A. Zürcher,…Schweizer Nationalfonds, BAFU, EU-INTAS
Thanks!