Vegetation-environment relationships in preforestcommunities in the Sierras de Cardeña y Montoro (Sierra

Morena, Southern Spain)

Vegetation-environment relationships in preforestcommunities in the Sierras de Cardeña y Montoro (Sierra

Morena, Southern Spain)Raya Ruz, J.1, Muñoz Alvarez, J.M.1, Sánchez Almendro, A.1, Porras Alonso, R.1,Quijada Muñoz, J.2, Moreira Madueño, J.M.2

1Department of Plant Biology. Botany Division. University of Cordoba. Spain2Consejería de Medio Ambiente. Andalusian Regional Council. Spain

IntroductionSierra Morena is one of the four major physiographical divisions of Andalusia. This mountain range runs transversally, mainly from NW to SE, and ranges in height between 80 m and 1300 m, the majority of peaks being around 500 m. Due to the predominance of slate, quartzite and granite-type rocks, the soils of Sierra Morena tend to be acid, and the hard underlying materials – coupled with extensive erosion – have given rise to poorly-developed soil profiles (Molina Vázquez, 2003). The semi-continental Mediterranean climate is marked by hot summers; the influence of the ocean from the West is generally noted in winter (Pita López, 2003).

Due to its lithological and topographical characteristics, the soils of Sierra Morena are of little agricultural value, and the area may be classified as marginal; this is borne out by the predominant forms of land use: forestry, livestock-raising and hunting. The proportion of land used for crops within Sierra Morena is negligible.

The Sierras de Cardeña y Montoro Natural Park is located within the structural region of Sierra Morena, in the province of Cordoba (Fig. 1). A study was made as part of a project to draw up a digital 1:10.000 vegetation map. Outstanding among the communities for their species richness, the extent to which they were representative of Mediterranean vegetation, their position in the process of succession and their degree of naturalness were the shade-loving preforest scrub communities belonging to the alliance Ericion arboreae and the association Phillyreo angustifoliae-Arbutetumunedonis Rivas Goday & Galiano (Rivas Goday et al., 1960). The steep slopes with which they tend to be associated make them one of the most marginal types of natural vegetation. Analysis of vegetation samples highlighted the variability of these communities, apparently linked to changing ecological conditions, mainly the degree of slope.

The aims of this study were to analyze variability in these shade-loving preforest scrub communities and relate it to certain environmental parameters.

Material and methodsDescription of the territoryThe Sierras de Cardeña y Montoro Natural Park is located in the east of Cordoba province, in theeastern half of Sierra Morena. The relief may be divided into two major units: a central peneplaincomprising fairly smooth forms, at a mean height of 750 m, bordered to the south of the Park by a series of ravines caused by river erosion, where mean height drops to around 200 m. Underlying rocks are predominantly Paleozoic, particuarly plutonic acid rocks (granite) and slates (Melendo, 1995). Mean rainfall is 812 mm, annual mean temperature is between 12 to 15º C and the annual mean number of days of frost ranges from 10 to 20 (Pita López, 2003).

Analysis of vegetationVegetation was studied using the phytosociology method (Müeller-Dombois & Ellenberg, 1974). A total of 34 relevés of shade-loving preforest scrub communities were subjected to various types of multivariate analysis (TWINSPAN and DCA), Kent & Coker, 1992 using PC-Ord 4.0 (Gilliam & Saunders, 2003) and the Community Analysis Package 3.022 (Seaby et al., 2004). The cut-levels for the pseudospecies used in TWINSPAN were 0, 2, 5, 20, 60 and 80, whilst program default options were used for DCA. The indicator value was assigned to the preferential species in which it was highest: Ij = nj+ / n+ – nj- / n- (Ij = indicator value for the jth pseudospecies; n+ and n- = total number of quadrats in the positive and negative groups; nj+ = number of quadrats in the positive group which have the jth pseudospecies; nj- = idem in the negative group). Given that not all herbaceous species were present throughout the year, and that relevés were taken in different months, annual species were eliminated from all inventories prior to analysis.

For each relevé, a digital elevation model with a resolution of ten meters was used to additionally analyze height, annual mean temperature, annual mean rainfall, aspect and slope. A 1:10.000 topographical map of Andalusia was used to calculate the distance between each relevé site and the nearest watercourse (a variable indicating the degree of atmospheric humidity), and the distance to the opposite hillside (an indirect indicator of hours of sunlight).

To check for possible differences in variables in the groups differentiated using TWINSPAN, a two-sample Wilcoxon non-parametric test for means comparison (S Plus 6.0) was applied to each of the variables.

Results and discussionClassification of relevés using TWINSPAN revealed two clearly-separated groups in the first division: one comprising mainly communities dominated by strawberry-tree (Arbutus unedo): Arbutus unedo-Erica arboreacommunity, and the other consisting primarily in communities dominated by mock-privet (Phillyrea latifolia): Phillyrea latifolia-Pistacia terebinthus community (Fig. 2).

This classification was borne out in the DCA graphical representation, which displayed a clear separation of communities dominated by strawberry trees and by mock-privet with respect to axis 1 (Fig. 3). The different distribution of the indicator species was also clearly apparent (Fig. 4).

Pistacia terebinthus and Olea europaea var sylvestris, indicator taxa for communities dominated by mock-privet, tend to be associated with habitats containing a large proportion of surface rock, themselves usually associated with steep hillsides. DCA analysis (Fig. 9) also disclosed high values with respect to axis 1 for largely rock-dwelling species such as Asplenium trichomanes, Umbilicus rupestris, Juniperus oxycedrus, Asplenium onopteris, Ceterach officinarum, Digitalis purpurea and Saxifraga granulata.

Analysis of environmental variables (Fig. 5, table 2) confirmed, first and foremost, the extremely marginal nature of these communities, located on hillsides with a slope ranging from 35% to 82%. This would also account for the degree of conservation of these species, in areas hostile to any form of human management. Secondly, analysis highlighted significant differences in slope between communities dominated by strawberry-tree and by mock-privet, the latter occurring on steeper slopes (Table 2). Mean values for height, distance from nearest watercourse and from opposite hillside confirms that communities dominated by mock-privet occurred lower down than communities dominated by strawberry-trees, although differences were not significant. No significant differences were noted for the remaining variables tested. Since both are shade-loving communities, orientation-related environmental conditions were similar.

ConclusionShade-loving preforest shrub communities in the Sierras de Cardeña y Montoro Natural Park were among the most marginal communities. Two community groups were detected, one dominated by Arbutus unedo with high values for Erica arborea and Phillyrea angustifolia, and the other by Phillyrea latifolia together with Pistacia terebinthus, Olea europaea var sylvestris and Asplenium onopteris as differentiating taxa. Degree of slope was identified as the main environmental parameter responsible for variability.

Bibliography-Gilliam, F. S. & Saunders, N. E. (2003). Making more sense of the order: A review of Canoco for Windows 4.5, PC – ORD version 4 and SYN – TAX 2000. Journal of Vegetation Science 14: 297-304.

-Kent, M. and Coker, P. (1992). Vegetation Description and Analysis. A Practical Approach. CRC Press, Inc., 2000 Corporate Blvd., N. W., Boca Raton, Florida.

-Melendo, M. (1995). Estudio de la flora y vegetación del Parque Natural Sierras de Cardeña y Montoro(Córdoba). Tesis de Licenciatura. Universidad de Granada.

-Molina Vázquez, F. et al. (2003). Dehesas de Sierra Morena. Reserva de la Biosfera. Consejería de Medio Ambiente. Junta de Andalucía.

-Müeller-Dombois, E. & H. Ellenberg (1974). Aims and methods of vegetation ecology. John Wiley & Sons. New York.

-Pita López, M. F. (2003). El clima de Andalucía. En A. López Ontiveros (coord.), Geografía de Andalucía, pp137-173. Ed. Ariel. Barcelona.

-Rivas Goday, S., J. Borja, F. Esteve, E. F. Galiano, A. Rigual & S. Rivas-Martínez (1960): Contribución al estudio de la Quercetea ilicis hispanica. Conexión de las comunidades hispánicas con Quercus lusitanica s.l. y sus correlaciones con las alianzas de Querecetalia ilicis, Quercetalia pubescentis y Quercetalia robori-petraeae. Anales Inst. Bot. Cavanilles 17 (2): 285-406. (Effect. Publ.: 27.04.1960).

-Seaby, R., P. Henderson, J. Prendergast & R. Somes (2004). Community Analysis Package 3.0. Searching for structure in community data. Pisces Conservation Ltd.

Phillyrea latifolia-Pistacia terebinthus communityPhillyrea latifolia-Pistacia terebinthus community(inside)

-139

-39

61

161

261

361

461

-184 -84 16 116 216 316

DCA-axis 1 (eigenvalue = 0,60)

DC

A-a

xis

2 (e

igen

valu

e =

0,1

6)

Arbutus unedo-Erica arboreacommunity

Phillyrea latifolia-Pistacia terebinthuscommunity

Arbutus unedo-Erica arborea communityArbutus unedo-Erica arborea community (inside)

Detail of leaves, flowers and fruits of Arbutusunedo

Fig. 1.- Landsat Image of Andalusia, Spain (30 m resolution). Geograficaldistribution of Sierra Morena, and Sierras de Cardeña y Montoro N.P.

Table 2.- Graphic representation of the mean value of seven analyzed enviromental variables. 1-Arbutus unedo-Erica arborea community (n: 21); 2-Phillyrea latifolia-Pistacia terebinthus community (n: 13)

Table 1.- The floristic composition of shade-loving preforest scrub communities of Sierras de Cardeña y Montoro N.P. arranged by TWINSPAN (species on less than 2 plots are omitted; cluster 1: Arbutus unedo-Erica arborea community, cluster 2: Phillyrea latifolia-Pistacia terebinthus community) and the frecuency class (I-V) ofspecies with mean abundance (1-5)

Fig 2.- TWINSPAN classification of vegetation data, showing the species with the highest indicator value (+0,5 < Ij < +1, -0,5 > Ij > -1). In bold, indicator species defined by TWINSPAN. The number placed after each species indicates the pseudospecies. Superscript numbers indicate total sample number in each group, and eigenvalue

Fig 3.- DCA ordination diagram showing plot scores

Fig 4.- DCA ordination diagram showing species scores. Principal indicator species are shown

Number of cluster 1 2 Number of relevé 444444555555555555556 4444555555555

888999000001111222237 8999000122223 139258023594589056716 8069167014890

Size (x 100 sq. m.) 112112122122111121212 1222212211121 Altitude (m.) 424645655646465456634 4435543466453 294450208298814745788 4457573109947 055055000050050000500 0000555500055 Aspect (grades) 33––––2211––3333–3––– 3––323–––1––– 558578878953225411744 6654935230491 000500000000005555050 0050055500005 Slope (%) 457673645455235553563 7757685768655 685005020638956506605 6050807052740 Mean height (m. x 0,1) 434444–43354355534344 4155336364544 550000–05500500050700 0900570005055 Arbutus unedo (Arb une) 553645654555445643653 11–314221231– V.5; V.2 Phillyrea angustifolia (Phi ang) 321331323221312222232 –1––2––33–2–– V.2; II.2 Erica arborea (Eri arb) 323332223333143334333 –––111–1–3–1– V.3; III.1 Quercus coccifera (Que coc) 3342532353–3432334133 4333133222––1 V.3; V.2 Cistus savifolius 11–131111––22–––11111 –1––1––1––––– IV.1; II.1 Cytisus scoparius 111111–––––1–11–11––– –1––––––––––– III.1; +.1 Narcissus triandrus 1––––––––––––1––––––– ––––––––––––– +.1; - Quercus faginea subsp broteroi 3–23––2–––32–31–3–––1 1112––2–213–– III.2; IV.2 Cistus albidus –11111111––22–––2111– –1––11–2––––– IV.1; II.1 Phagnalon saxatile –1––––11––––––––1–1–– ––––––––––––1 II.1; +.1 Quercus rotundifolia –343–1–3–213313–313–3 33––––21––––– IV.2; II.2 Teucrium fruticans –1––2–––11––––––1–11– ––––––––––––– II.1; - Lonicera implexa (Lon imp) –22331–11––211121–1–– 11–1––1––2––– IV.2; II.1 Thapsia villosa –1–––––11––––––––1––– –1––––––––––– I.1; +.1 Asparagus acutifolius (Asp acu) –1––––––––––––1–––––– –––––––1––––– +.1; +.1 Rubia peregrina (Rub per) –111111111––––1–111–– 11––––1–––––– IV.1; II.1 Adenocarpus telonensis (Ade tel) –1––––––––––––––––1–– ––––––––––––– +.1; - Cistus populifolius (Cis pop) –1–1–1––1––1––––––––– ––––––––––––– II.1; - Rubus ulmifolius ––1––––1––11––––––1–– 1–––––––––––– II.1; +.1 Viburnum tinus (Vib tin) ––231––––––1––213–1–– ––––––––––––– II.2; - Thymus mastichina (Thy mas) ––1–––––––––––––1–––– ––––––––––––– +.1; - Daphne gnidium (Dap gni) ––11111111––1–1–111–1 ––––––1–––––– IV.1; +.1 Thapsia maxima –––2111––––––1––––1–– –1––––––––––– II.1; +.1 Cistus ladanifer –––1111131–––––––11–1 –––––1––––––– III.1; +.1 Aristolochia paucinervis –––2–––––1–1––––1–––– –––––1––––––1 I.1; I.1 Asphodelus ramosus (Asp ram) –––1–222––––1–––––1–– ––––1–––––1–1 II.2; II.1 Gladiolus illyricus (Gla ill) –––––11–––––––––––––– ––––––––––––– +.1; - Helichrysum stoechas (Hel sto) –––––1––––––––––1–1–– ––––––––––––– I.1; - Lavandula stoechas –––––1112–––1–––111–1 –––––––1––––– III.1; +.1 Bituminaria bituminosa –––––11–11––––––––––– ––––––––––––– I.1; - Urginea maritima –––––11111––––––––1–– ––––11––––1–– II.1; II.1 Melica minuta –––––––––1–1––––––1–– ––––1––1––––– I.1; I.1 Rumex angiocarpus (Rum ang) –––––––––––1–1–––11–– ––––––––––––– I.1; - Rosmarinus officinalis (Ros off) –––––––––––112–––21–– ––––––––––––– II.1; - Umbilicus heylandianus ––––––––––––––11––––– ––––––––––––– +.1; - Quercus suber (Que sub) ––––––––––––––––31––1 ––––––––––––– I.2; - Pistacia lentiscus 314–3121332–2––32–122 233–433131341 IV.2; V.3 Ruscus aculeatus 1–11–1–––1–1–11–––––– ––1–1–21––1–– II.1; II.1 Smilax aspera 2––––––––––––––3––––– ––3–2–3–––13– +.3; II.2 Tamus communis 111111–1––1–––11–––1– 111–111–1111– III.1; IV.1 Selaginella denticulada (Sel den) –11––11–––1–––––––––– –1–1111–––11– II.1; III.1 Anogramma leptophylla –111–––1–1111––––1––– 1111111––1––– III.1; IV.1 Olea europaea v sylvestris (Ole eur) –1––11–––11–––––––111 ––3–2223––323 II.1; IV.3 Bryonia cretica subsp dioica –1–1–––––––1––––––––– 111–––––––––1 I.1; II.1 Rhamnus alaternus –2–––––1––1––––3––1–– ––2121–––1–1– II.2; III.1 Jasminum fruticans ––11––––––––––––––––– 32––1––2––––– +.1; II.2 Phillyrea latifolia (Phi lat) ––3–2313–12–1––1––12– 4555445366554 III.2; V.5 Asplenium trichomanes (Asp tri) ––1––1––––––––––––––– 1––1–1–––1––– +.1; II.1 Umbilicus rupestris (Umb rup) –––––1–1–––1––––––––– 1––1111––1––– I.1; III.1 Asplenium onopteris (Asp ono) ––1––1–––––1––––––––– 1–111111–11–– I.1; IV.1 Crataegus monogyna (Cra mon) ––1–––––––––––––––––– 1–––––––––––– r.1; +.1 Asplenium adiantum-nigrum ––1–––––––––––––––––– 111–––––––––– r.1; II.1 Carex distachya ––1–––1–––––––––––––– 1–––1–––––1–– +.1; II.1 Hyacinthoides hispanica –––11––––––1––11––––– 11––––––11––– II.1; II.1 Pistacia terebinthus (Pis ter) ––23–1–––––11–––––111 3333313333132 II.1; V.3 Paeonia broteroi ––1–––––––––––––––––– –1–––––––1––– r.1; I.1 Ceterach officinarum (Cet off) ––––––––––––––––––––– –1–––1––––––– - ; I.1 Vincetoxicum nigrum ––––1–––––––––––1–––– –––––––111––– +.1; II.1 Arum italicum (Aru ita) ––––––––––––––––––––– ––1–––1–––––– - ; I.1 Arisarum simorrhinum (Ari sim) ––––––11–1––––––––––– ––1–11––––––– I.1; II.1 Myrtus communis –––––––2–3–––––––––1– –––––12–––3–1 I.2; II.2 Juniperus oxycedrus (Jun oxy) –––––––––––––––––––3– ––––––12––––3 r.3; II.2 Vitis vinifera subsp. sylvestris ––––––––––––––1–––––– ––––––3–1–––– r.1; I.2 Ferula communis (Fer com) ––––––––––––––––––––– ––––––––2––1– - ; I.2 Bromus matritensis (Bro mat) ––––––––––––––––––1–– –––––––––––11 r.1; I.1

34

21 13

0,321

Erica arborea 2 (I = -0,79)

Arbutus unedo 5 (I = -0,71)

Daphne gnidium 1 (I = -0,59)

Phillyrea angustifolia 3 (I = -0,50)

Phillyrea latifolia 5 (I = 0,92)

Pistacia terebinthus 2 (I = 0,76)

Olea europaea var sylvestris 2 (I = 0,61)

Asplenium onopteris 1 (I = 0,59)

Mean SD Range W P Community 1 2 1 2 1 2 Altitude (m) 514,52 453,49 110,35 104,75 292,99-704,85 297,74-614,67 412 0,120 Slope (%) 50,76 71,85 12,12 13,32 29,00-75,00 50,00-97,00 -3,393 0,0002*

Aspect cosine 0,59 0,61 0,62 0,35 -0,99-1 -0,16-1 -0,567 0,571 Annual Mean Temperature (ºC) 16,15 16,39 0,48 0,48 15,29-17,16 15,74-17,17 330 0,193 Annual Mean Precipitation (l) 677,49 658,73 50,02 45,72 564,19-764,90 594,59-762,12 396 0,326 Water-course Distance (m) 125,59 73,44 125,61 72,97 3,17-501,76 1,4-227,08 407 0,169 Hillside distance (m) 377,48 148,43 420,91 119,91 6,95-1618,18 3,71-334,69 413 0,112

Fig 5.- Mean values of the environmental variables in Arbutus unedo-Erica arboreacommunity (1) and Phillyrea latifolia-Pistacia terebinthus community (2) of the

Sierra MorenaCardeña

1 2

Vegetation Type

15.0

15.5

16.0

16.5

17.0

An

ual

mea

n T

emp

erat

ure

(ºC

)

1 2

Vegetation Type

520

570

620

670

720

770

An

nu

al m

ean

Pre

cip

itat

ion

(l)

1 2

Vegetation Type

200

300

400

500

600

700

Alti

tud

e (m

)

1 2

Vegetation Type

0

10

20

30

Slo

pe

(%)

1 2

Vegetation Type

0

500

1000

1500

Hill

sid

e D

ista

nce

(m

)

1 2

Vegetation Type

0

100

200

300

400

500

Wat

er-c

ou

rse

Dis

tan

ce (m

)

1 2

Vegetation Type

-1.0

-0.5

0.0

0.5

1.0

Asp

ect C

osi

ne

-139

-39

61

161

261

361

461

-184 -84 16 116 216 316

DCA-axis 1 (eigenvalue = 0,60)

DC

A-a

xis

2 (e

igen

valu

e =

0,1

6)

Species of Arbutusunedo-Ericaarborea community

Species of Phillyrealatifolia-Pistaciaterebinthuscommunity

Que sub

Vib tin

Ros offAsp aes

Rum angHel sto

Ade tel

Eri arb

Cis pop

Gla ill

Thy mas

Lon imp

Dap gni

Arb une

Asp ram

Cra monQue coc

Rub per

Phi ang

Asp tri

Asp onoSel den

Ari sim

Bro mat

Jun oxy

Pis ter

Phi lat

Ole eur

Aru ita

Fer com

Dig pur

Rha ole

Cet off

Umb rup

Sax gra