Original scientific article	UDC 581.52:547.4(497.4)
Received: 2010-05-21
RELATION BETWEEN CSR FUNCTIONAL SIGNATURES OF DRY GRASSLANDS FROM TWO CONTRASTING GEOLOGICAL SUBSTRATES
Sonja ŠKORNIK
Department of Biology, Faculty of Natural Sciences and Mathematics, University of Maribor, SI-2000 Maribor, Koroška 160, Slovenia
E-mail: sonja.skornik@uni-mb.si
Klavdija HARTMAN Cinžat 1 7, SI-2343 Fala, Slovenia
Mitja KALIGARIC
Department of Biology, Faculty of Natural Sciences and Mathematics, University of Maribor, SI-2000 Maribor, Koroška 160, Slovenia
ABSTRACT
The paper presents floristic and functional comparison of two adjacent and structurally similar plant communities - calcareous (Bromion erecti) and silicicolous (Nardo-Agrostion tenuis) dry grasslands. For functional comparison Grime's CSR triangle theory of plant strategies was used. The analysis of species composition showed great differences between both dry grassland types. Higher relative proportions of S component and lower relative proportions of C components in silicicolous grasslands suggest that those habitats generally experience higher intensities of stress when compared to calcareous grasslands, presumably owing to low resource availability on high-acidic sites and also due to their occurrence in higher altitudes.
Key words: calcareous dry grasslands, silicicolous dry grasslands, species composition, plant functional types, plant
traits, Slovenia
RELAZIONE TRA SIGLE FUNZIONALI CSR Dl PASCOLI ARIDI SU DUE SUBSTRATI GEOLOGICI CONTRASTANTI
SINTESI
L'articolo presenta la comparazione floristica e funzionale fra due comunita vegetali adiacenti e strutturalmente simili - calcarea (Bromion erecti) e silicea (Nardo-Agrostion tenuis) di pascoli aridi. Per la comparazione funzionale e stato usato il modello CSR di Grime, inerente alle strategie ecologiche delle piante. L'analisi della composizione delle specie ha evidenziato notevoli differenze fra i due tipi di pascoli aridi. Maggiori proporzioni relative della componente S e minori proporzioni della componente C nei pascoli aridi silicei suggeriscono che tali habitat generalmente sono sottoposti a maggiori intensita di stress in confronto ai pascoli aridi calcarei. Tale risultato presumibilmente e collegato alla minore disponibilita di risorse in siti ad alta acidita e al fatto che tali pascoli si trovano ad altitudini elevate.
Parole chiave: pascoli aridi calcarei, pascoli aridi silicei, composizione di specie, tipi funzionali vegetali,
caratteristiche morfologiche vegetali, Slovenia
Sonja ŠKORNIK et a/.: RELATION BETWEEN CSR FUNCTIONAL SIGNATURES OF DRY GRASSLANDS ..., 101-112
INTRODUCTION
The traditional approach to vegetation classification is taxonomic in nature and usually performed at the species level (Duckworth ef a/., 2000). On a large scale, predictions based on plant species are geographically bound (Woodward & Cramer, 1996). On a small scale, species are in some cases so widely spread and variable that by describing communities by species composition we may not perceive relevant patterns occurring below the resolving power of species (Diaz ef a/., 1992). Consequently, classifying plant species according to their higher taxonomical level has strong limitations when it comes to answering important ecological questions at the scale of ecosystems, landscapes or biomes (Keddy, 1992; Korner, 1993). A promising way for answering such questions, as well as various other ecological questions, is by classifying plant species by their shared biological characteristics that relate to function, rather than by phylogeny (Grime ef a/., 1988; Lavorel ef a/., 1997; Diaz ef a/., 2002). These alternative classes are often referred to as plant functional types or groups (Leishman & Westoby, 1992; Grime ef a/., 1988; Gitay & Noble, 1997). Plant functional types can be defined as groups of plant species sharing similar functioning at the organismic level, similar responses to environmental factors (e.g., temperature, water availability, nutrients, fire and grazing), and/or similar roles in (or effects on) ecosystems or biomes (e.g., productivity, nutrient cycling, flammability and resilience) (Walker, 1992; Chapin ef a/., 1996; Nobble & Gitay, 1996; Diaz & Cabido, 1997; Lavorel ef a/., 1997; Grime, 2001). With plant functional types, comparisons between communities of widely differing composition can be facilitated (Diaz ef a/., 2004).
The underlying bases for schemes of plant functional types can vary widely (Ramenskiy, 1938; Hermy & Stieperaere, 1985; Grime, 2001). One of three-type schemes, the so-called "CSR plant strategy theory" (Grime, 1974, 1977, 1979, 2001) is particularly efficient in the balance between the power of its predictions and the simplicity of its assumptions (Hunt ef a/., 2004). Grime (1974, 1977, 1979, 2001) developed a classification based on how plants deal with two groups of external environmental factors, stress and disturbance. This scheme results in three primary plant strategies: competitors (C), stress-tolerators (S), and ruderals (R) and several intermediate strategies. The position of any species can be displayed upon a triangular ordination diagram (Grime, 1974, 2001; Hodgson ef a/., 1999). Each strategy is characterized by a distinct set of ecological, morphological and physiological traits and is found in species occupying habitats of a particular kind (Grime ef a/., 1988). Hodgson ef a/. (1999) developed a methodology that classifies unknown herbaceous subject based on validated "soft" traits (/.e. relatively unde-
manding), allowing practical ordination of wild plants within CSR space. The position in CSR diagram can be determined also for an entire vegetation sample (relevé). Hunt ef a/. (2004) presented a quantitative tool which facilitates the reduction of herbaceous plant communities to collections of functional types. The whole community is given a "functional signature", a three-part numerical index which concisely represents the balance between the different functional attributes that are present among the component species (Hunt ef a/., 2004). The integrative power of the CSR signature is useful in comparative studies involving widely differing samples (Hunt ef a/., 2004). Although Grime's CSR triangle theory has been often criticized (Tilman, 1988; Silvertown ef a/., 1992; Wilson & Lee, 2000), Grime's ideas remain fundamental to the development of functional classifications and functional interpretation of plant communities (Hills ef a/., 1994; Caccianiga ef a/., 2006; Pipenbaher ef a/., 2008; Zelnik & Carni, 2008).
The aim of the present study was to determine whether two contrasting geological substrates - calcareous and silicicolous, affect the CSR functional signatures of related grasslands, being floristically substantially distinct. We actually compared species composition and plant life strategies as defined by Grime (1974) of two adjacent and structurally-similar plant communities on acidic and calcareous soils from the central part of Slovenia - acidic Matgrass (Nardus sfr/cfa) grasslands and species-rich calcareous grasslands. We applied the method of Hodgson ef a/. (1999) to allocate CSR plant functional types and the approach of Hunt ef a/. (2004) to derive a functional signature for the researched grasslands communities. These vegetation types were created by traditional, infrequent low intensity grazing or mowing with no external inputs (fertilizers) in the past (Skornik, 2003; Kaligaric ef a/., 2006). They represent grasslands of moderate productivity and despite contrasting geological substrates both vegetation types represent habitats subject to a similar combination of intermediate level of disturbance and stress due to nutrient poor and shallow rocky soils which experience desiccation during the summer. We hypothesized that despite wide differences in plant species composition there are no significant differences in functional signatures between calcareous and silicicolous grassland types with respect to C, S and R components, since they both represent habitats experiencing nearly comparable effects of climate and land-use.
MATERIALS AND METHODS Study area
The studied calcareous semi-dry grasslands appear only in small fragments in the hilly region of pre-Alpine and pre-Pannonian region and on low Dinaric and pre-
Sonja ŠKORNIK et al.: RELATION BETWEEN CSR FUNCTIONAL SIGNATURES OF DRY GRASSLANDS ..., 101-112
Fig. 1: Map of Slovenia with locations of the collected relevés of calcareous (•) and silicicolous (O) dry grasslands. SI. 1: Karta Slovenije z lokalitetami popisov suhih travnikov na apnencih (•) in silikatih (O).
Dinaric karst plateau at ca. 500-1100 m a.s.l. (Fig. 1). The geological substrate is made of calcareous limestone and dolomite. The climate is continental with mild to hot summers and cold winters. Mean annual temperature is between 6 and 10.5"C. The average annual precipitation is between 1000 and 1300 mm. The relevés of studied calcareous semi-dry grasslands belong to species-rich meadows from the Bromion erecti alliance described as association Scabioso hladnikianae-Caricetum humilis (Skornik, 2001). These grasslands are distributed over exposed sunny and dry areas and are therefore rich in xero-thermophilous and basiphilous species.
The silicicolous Matgrass grasslands were studied on the summit areas of Pohorje Mountains (NE Slovenia) (Fig. 1) at altitudes at ca. 1500 m a.s.l. We analysed relevés of association Homogyno alpinae-Nardetum (alliance Nardo-Agrostion tenuis, order Nardetalia) (Kaligaric & Skornik, 2002). Pohorje, the most dominant mountain range in the NE Slovenia, is situated at the south-easternmost edge of the Central (non-carbonate) Alps. The main characteristic of these grasslands are acid soils (pH less than 4.0), the result of the non-carbonate geological bedrock, predominantly metamor-phic rocks and granodhiorythic lacolith (Hinterlechner-Ravnik, 1995). The study area has the montane climate with fresh summers and cold winters. The average temperature in the coldest month is below -3"C and in the warmest month above 10"C. The average annual pre-
cipitation is approx. 1336 mm (Ribniska koca, 1530m) (Furlan, 1980). These grasslands occur mainly on flat plains and gentle sloping ridges with very dry and shallow soils, poor with minerals and with low pH values (Kaligaric & Skornik, 2002). They are rich in species designated as xerophilous and acidophilous species.
Vegetation survey
We analysed 30 relevés of dry grasslands on calcareous bedrock - association Scabioso hladnikianae-Caricetum humilis (Skornik, 2001) and 32 vegetation relevés of dry grasslands on silicicolous bedrock - association Homogyno alpinae-Nardetum (Kaligaric & Skornik, 2002). Relevés were collected using standard procedure of the sigmatistic method (Braun-Blanquet, 1964; Westhoff & van der Maarel, 1973; Dierschke, 1994).
Allocating a CSR plant functional type to plant species and vegetation samples (relevés)
The CSR scheme takes into account a number of different plant traits (Hodgson et al., 1999). To determine one of 19 CSR functional types for 122 plant species recorded in 62 analysed vegetation relevés we used a rapid method for attribution of CSR type from simple measurements and data published by Hodgson et al. (1999). We used the following plant traits: canopy
Sonja ŠKORNIK et al.: RELATION BETWEEN CSR FUNCTIONAL SIGNATURES OF DRY GRASSLANDS ..., 101-112
height, leaf dry matter content, flowering period, flowering start, lateral spread, leaf dry weight, specific leaf area. Traits were chosen from our own database (protocol standardized by Cornelissen et al., 2003). Calculations of CSR coordinates were made by entering these data into the spreadsheets of Hodgson et al. (1999), made available for this purpose at www.ex.ac.uk/ ~rh203/allocating_csr.html. For 21 plant species we used data from a look-up table with CSR types for 1000 European species (source J. G. Hodgson, UCPE Sheffield).
The relative proportions of CSR functional types for our 62 samples (relevés) of vegetation were calculated and plotted in CSR triangle by using spreadsheet-based tools of Hunt et al. (2004), available at www.people. exeter.ac.uk/rh203/allocatingcsr.html.
To test differences in relative proportions of C-, Sand R-strategists among relevés of calcareous and silici-colous dry grasslands, we used a Student's t-test for independent samples (SPSS Inc., 2006), since the data were sufficiently normally distributed (Shapiro-Wilks and Lilliefors tests).
Nomenclature
Taxonomic nomenclature follows Martincic et al. (2007), syntaxonomic nomenclature follows Mucina et al. (1993), Grabherr & Mucina (1993) and Skornik (2003).
RESULTS
The total number of vascular plant species recorded in 62 relevés of studied grassland communities was 143 with 105 in the calcareous (mean=45±6.8 per plot, N=30) and 45 (mean=16±3.8 per plot, N=32) in the silicicolous grasslands. There are only 7 common species, namely Antennaria dioica, Anthoxanthum odora-tum, Cruciata glabra, Gymnadenia conopsea, Luzula campestris, Potentilla erecta and Veronica chamaedrys, 98 exclusive to the calcareous and 38 exclusive to the silicicolous semi-dry grasslands. All species are listed in Appendix 1.
Characteristic of calcareous semi-dry grasslands are particularly many calciphilous and xerophilous species, such as Acinos alpinus, Anthericum ramosum, Bromop-sis erecta, Centaurea scabiosa subsp. fritschii, Globularia punctata, Helianthemum ovatum and Koeleria pyrami-data, which are absent on non-carbonate soil. In silicicolous grasslands calcifuge species which can tolerate soil with lower pH values appear, such as Arnica montana, Calluna vulgaris, Carex pilulifera, Festuca rubra, Hieracium pilosella, Nardus stricta and Ranunculus acris.
Ordination of species within CSR space (Tab. 1) demonstrate that CR, SC, CSR and the combination of SC and CSR types are prevalent strategies of plant species on both calcareous and silicicolous semi-dry grasslands. The most frequent are competitive-ruderals (CR), which were especially strongly represented in the species composition of silicicolous semi-dry grasslands (33.34%). Examples of competitive-ruderals are species Agrostis capillaris, Carlina acaulis, Cirsium pannonicum, Linum catharticum, Plantago media, Rhinanthus gla-cialis and Stellaria graminea. Stress-tolerant competitors (SC) included some grasses, sedges and rushes, e.g. Carex flacca, Deschampsia caespitosa, Luzula luzuloi-des and Molinia caerulea. CSR strategists include small geophytes (e.g. Orchis tridentata, Orchis ustulata and Primula veris), small deep-rooted forbs with rosettes (e.g. Antennaria dioica, Plantago lanceolata, Scabiosa columbaria, Silene vulgaris) and small sedges like Carex ornithopoda (Append. 1 ).
Tab. 1: CSR strategies of 143 plant species recorded in 62 relevés of dry grasslands from calcareous (30 relevés) and silicicolous (32 relevés) geological substrates. Values are percentage frequencies. Tab. 1: CSR strategije 143 rastlinskih vrst suhih travnikov na karbonatni (30 popisov) in silikatni (32 popisov) geološki podlagi. Vrednosti v tabeli ustrezajo frekvencam (%) pojavljanja vrst.
	Calcareous	Silicicolous
N of relevés	30	32
N of plant species	105	45
CSR plant strategy		
C	2.9	0.0
S	1.0	0.0
R	0.0	0.0
CR	19.1	33.3
SR	1.0	0.0
SC	17.1	11.1
CSR	17.1	8.9
C/CR	4.8	2.2
C/SC	3.8	2.2
C/CSR	3.8	0.0
CR/CSR	1.9	4.4
R/CR	2.9	4.4
R/CSR	0.0	0.0
R/SR	1.0	0.0
SR/CSR	4.8	2.2
SC/CSR	5.7	15.6
S/SC	5.7	6.7
S/CSR	5.7	6.7
S/SR	1.9	2.2
Sonja SKORNIK et a!.: RELATION BETWEEN CSR FUNCTIONAL SIGNATURES OF DRY GRASSLANDS ..., 101-112
The positions of calculated functional signatures for all 62 relevés of studied grasslands in CSR space are presented in Figure 2. Relevés are arranged on the right side of the triangle along the line, where stress and competition in various equilibria are the most important determinants of the vegetation.
When calculating functional signatures, we considered the percentage of abundance of each plant species in relevé. Differences in functional signatures within the samples (relevés) of both vegetation types are due to fluctuations in abundance of dominant species which can be linked to differences in soil characteristics of microhabitat or to disturbance abundance (Fig. 2). Relevés of calcareous grassland positioned in the upper part of the triangle represent less-managed grasslands that exhibit conditions favourable to the species with stressed C component, such as Brachypodium pinnatum, Centaurea scabiosa subsp. fritschii and Peucedanum oreoseli-num. The relative importance of S-coordinate in the part of relevés of silicicolous grasslands was revealed due to the strong dominance of stress-tolerant grass species Nardus stricta in those vegetation samples.
The comparison of relative proportions of C, S and R components among relevés showed significantly (P <0.0001) higher relative proportions of S component (mean=0.52, N=32) in silicicolous grasslands than in calcareous grasslands (mean=0.37, N=30). On the other hand, calcareous grasslands had significantly (P
C
Fig. 2: CSR ordination of releves (N=62, 143 species) of dry grasslands from calcareous and silicicolous geological substrates. Legend: ■ - calcareous dry grasslands; O - silicicolous dry grasslands.
Sl. 2: CSR ordinacija popisov (N=62, 143 vrst) suhih travnikov na karbonatni in silikatni geološki podlagi. Legenda: ■ - popisi karbonatnih suhih travnikov; O -popisi silikatnih suhih travnikov.
<0.0001) higher relative proportions of C component (mean=0.46, N=30) than acid grasslands (mean=0.31, N=32).
DISCUSSION
As expected and observed for a long time (e.g., Gigon, 1987, Grime, 1979; Partel, 2002), great floristic differences between the calcareous and non-calcareous (silicolous) grasslands were found. These habitats have only a few common species and many species related to either basic or acidic soil pH. It is generally accepted that the main reason why some substrates host different plant species than others lies in chemical processes and factors rather than in physical ones (temperature, moisture, etc.) (Kinzel, 1983; Gigon, 1987).
The calcareous grasslands are characterized by high species richness, typical of these semi-natural grasslands (Bromion erecti) in extensive use, which are among the most species-rich habitats in Europe (Willems et a/., 1993). Partel (2002) and Ewald (2003) suggest that the relationship between local species density and soil pH is determined by regional species pool size (Zobel et a/., 1998), which in turn reflects the relative abundance of soil types during the evolutionary history of the flora. Ewald (2003) observed that calcareous sites in Central Europe have higher species density and larger species pool than acidic sites, and argues that this is due to a Pleistocene bottleneck for acidophiles. Peet et a/. (2003) contradict the assertion of Partel (2002) and Ewald (2003). They conclude that richness on higher pH sites is a result of generally more favorable conditions for plant growth and/or establishment. It is known that more baserich sites are generally more invasible (e.g., Davis et a/., 2000; Brown & Peet, 2003), presumably owing to greater resource availability on high-base sites. Under extreme acidity, the nutrient cations are so mobile that they are easily leached into groundwater (Gurevitch et a/, 2002).
CSR classification of all species recorded (Tab. 1) expresses the response on stress and disturbance in the studied grasslands. The three primary C-, S-, and R-strategists represent extremes in the range of conditions available to plants (Grime, 2001) and are therefore very rare in grasslands we have researched. Namely, these are habitats experiencing intermediate intensities of stress and disturbance and in such circumstances the vegetation usually includes many species with strategies intermediate between those of the competitor, the stress-tolerator, and the ruderal (Grime, 2001). For the investigated unfertilised dry grasslands, effect of disturbance is mainly due to the mowing once a year (or even every second year) and occasional grazing (Kaligarič & Skor-nik, 2002; Skornik et a/., 2006). Although these disturbances are severe, they occur infrequently and prevent dominance by competitors. The competitive nature of
Sonja ŠKORNIK et a/.: RELATION BETWEEN CSR FUNCTIONAL SIGNATURES OF DRY GRASSLANDS ..., 101-112
species in the present study is restricted also by moderate stress conditions, due to nutrient-deficient and shallow soils which experience desiccation during summer. Many species within competitive-ruderals and stress-tolerant competitors (e.g. $grosf/s cap/7/ar/es, Ca-rex I/acca, DescKamps/a caesp/fosa, 0o//n/a caeru/ea) are perennials showing capacity for rapid lateral vegetative spread and for efficient colonisation of temporary gaps (Lovett-Doust, 1981).
According to Hunt ef a/. (2004), the integrative power of the functional signatures within the context of the CSR system of plant functional types is especially useful in comparative studies of widely differing samples. We hypothesized that despite very different floristic composition there will be no significant differences in functional signatures between relevés of silicicolous and calcareous dry grasslands. Our results do not support our hypotheses, however, they agree with the observations that more base-rich sites are less stressful for plants. We can observe some relevés, which showed similar values of functional signatures (Fig. 2). These were samples of calcareous grasslands characterised by severe level of stress due to extremely shallow dry soil and less-managed or even unmanaged samples of silicicolous dry
grasslands. Species which were abundant in these habitats were stress-tolerant competitors (SC, S/SC). Examples are Carex Kum///s, .oe/er/a pyram/Gafa, LeonfoGon /n-canus, H/ppocrep/s comosa and D/anfKus carfKus/ano-rum, all species which were abundant in calcareous grasslands. The predominant stress-tolerant competitors in the case of overlapping acidic dry grasslands were members of the Ericaceae: Ca//una vu/gar/s, Vacc/n/um myrf///us and V. v/f/s-/Gaea. In Europe and North America these sclerophyllous shrubs species are very common and associated with nutrient-deficient acidic soils if management regimes allow the development of woody vegetation (Grime, 2001). Beside the soil chemistry, the altitudinal distribution of sample grasslands should not be neglected as well; the silicicolous grasslands were sampled in higher altitudes, where growing period is shorter and climatic conditions are sharper. These require plant strategies closer to S strategy, which was actually confirmed within the present study.
In conclusion, although some authors have expressed doubts concerning the predictive power of CSR theory (Wilson & Lee, 2000), we have demonstrated its usefulness in comparative analysis of plant communities of widely differing species composition.
PRIMERJAVA CSR FUNKCIONALNIH OZNAK SUHIH TRAVIŠČ Z DVEH RAZLIČNIH GEOLOŠKIH PODLAG
Sonja Š.ORN/.
Oddelek za biologijo, Fakulteta za naravoslovje in matematiko, Univerza v Mariboru, SI-2000 Maribor, Koroška 160
E-mail: sonja.skornik@uni-mb.si
./avG//a +4RTM4N Činžat 17, SI-2343 Fala
0/f/a .$L/G$R/Č
Oddelek za biologijo, Fakulteta za naravoslovje in matematiko, Univerza v Mariboru, SI-2000 Maribor, Koroška 160
POVZETE.
Z našo šfuG//o smo že/e// oGgovor/f/ na vprašan/e, a// raz//čna poG/aga - Narbonafna /n ne-Narbonafna s///Nafna vp//va na raz//Ne v CSR /unNc/ona/n/ oznaN/ GveK po sfruNfur/ poGobn/K rasf//nsN/K zGružb. Za lunNc/ona/no pr/mer-/avo smo uporab/'//' Gr/'me-ov moGe/ CSR eNo/ošN/K sfrafeg// rasf//n. Proučevan/ suK/ fravn/N/ preGsfav//a/o anfropoge-n/ Kab/faf, N/ /e nasfa/ Nof pos/eG/ca Go/gofra/ne fraG/c/ona/ne eNsfenz/vne paše oz. Nošn/e. To so frav/šča z zmerno proGuNcZ/o, N/ so N//ub Nonfrasfn/ geo/ošN/ poG/ag/ poGvržena pr/mer///v/ Nomb/nac/// zmerne mofn/e fer sfresa. S/eG-n// /e preGvsem pos/eG/ca poman/Nan/a Kran// v f/eK fer voGnega sfresa zaraG/ p//fN/K Namn/f/K fa/, N/ se v po/efn/K mesec/K pogosfo /zsuš//o. TaNo smo posfav/// K/pofezo, Ga N//ub ze/o raz//čn/ I/or/sf/čn/ sesfav/ ne bomo naš// sfaf/sf/-čno znač/7n/K raz//N v lunNc/ona/n/K oznaNaK za oba f/pa vegefac//e. $na//z/ra// smo 30 I/foceno/ošN/K pop/sov suK/K fravn/Nov na Narbonaf/K (asoc. Scabioso hladnikianae-Caricetum humilis, zveza Bromion erecti) fer 32 I/foceno/ošN/K pop/sov s/7/Nafn/K suK/K fravn/Nov (asoc. Homogyno alpinae-Nardetum, zveza Nardo-Agrostion tenuis). Na osnov/ pr/mer/ave I/or/sf/čne sesfave smo pofrG///, Ga se suK/ fravn/N/ na Narbonafn/ /n s/V/Nafn/ geo/ošN/ poG/ag/ meG sabo
Sonja ŠKORNIK et al.: RELATION BETWEEN CSR FUNCTIONAL SIGNATURES OF DRY GRASSLANDS ..., 101-112
zelo razlikujejo, saj se od zabeleženih skupno 142 vrst, samo 7 rastlinskih vrst pojavlja tako na silikatnih kot tudi na karbonatnih travnikih. Primerjavo tipov CSR ekoloških strategij smo izvedli na osnovi frekvenc (v %) pojavljanja vrst v skupinah popisov. Pokazala je, da je sestava CSR tipov ekoloških strategij na obeh tipih suhih travnikov zelo podobna. Na obeh traviščih prevladujejo vrste s t.i. sekundarnimi CSR ekološkimi strategijami C-R, C-S in CSR, značilne za vrste podvržene zmernemu stresu in motnji. Pri izračunavanju funkcionalih oznak popisov upoštevamo ne samo prisotnost/odsotnost temveč tudi pokrovnost vrst v popisih. Primerjava razporeditve funkcionalnih oznak popisov v CSR trikotniku je tako pokazala, da imata na proučevana suha travišča najpomembnejši vpliv stres in kompeticija v različnih razmerjih. Razlike v funkcionalnih oznakah med popisi znotraj posameznega tipa suhih travnikov se pojavljajo zaradi nihanja v pogostnosti dominantnih vrst, ki so posledica razlik v talnih razmerah ter stopnjah motnje. Kljub temu, da so si funkcionalne oznake nekaterih popisov iz različnih geoloških podlag zelo podobne, pa so statistične analize pokazale statistično značilne večje relativne deleže komponente S in manjše relativne deleže komponente C v popisih silikatnih travnikov. Naši rezultati tako ne podpirajo naše hipoteze, v kateri smo predvideli, da ne bomo našli statistično značilnih razlik v funkcionalnih oznakah za oba tipa vegetacije. Zato pa lahko naše izsledke uporabimo za potrditev domneve o bolj stresnih razmerah na rastiščih z nižjimi pH vrednostmi tal. Ta domneva namreč predstavlja enega izmed najpogostejših odgovorov, ki ga različni raziskovalci ponujajo na zelo znano vprašanje v ekologiji rastlin, zakaj obstaja toliko večja vrstna pestrost na tleh z višjimi vrednostmi pH v primerjavi s tlemi z nižjimi pH vrednostmi.
Ključne besede: karbonatni suhi travniki, silikatni suhi travniki, vrstna sestava, funkcionalni tipi rastlin, morfološke
poteze rastlin, Slovenija
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Species	CSR plant strategy	Calcareous	Silicicolous
			
Acinos alpinus	CSR*	70	
Agrostis capillaris	CR		9
Anacamptis pyramidalis	R/CR	20	
Anemone nemorosa	C/SC		19
Antennaria dioica	CSR*	17	2S
Anthericum ramosum	C/CR	S7	
Anthoxanthum odoratum	SR/CSR	20	16
Anthyllis vulneraria	CR	80	
Arnica montana	CR		97
Arrhenatherum elatius	C/CSR	13	
Asperula cynanchica	SR/CSR	63	
Avenella flexuosa	SC/CSR		63
Avenochloa pubescens	CR	13	
Betonica officinalis	C/CR	13	
Brachypodium rupestre	C	100	
Briza media	SC/CSR	80	
Bromopsis erecta agg.	C/CSR	83	
Buphthalmum salicifolium	CR	93	
Calluna vulgaris	SC		78
Campanula barbata	CR		7S
Carex caryophyllea	S	87	
Carex flacca	SC	60	
Carex humilis	S/SC	S0	
Carex montana	S/SC	70	
Carex ornithopoda	CSR*	27	
Carex pilulifera	SC/CSR		34
Carlina acaulis	CR	67	
Carlina vulgaris	CR	13	
Centaurea pannonica	CR	10	
Centaurea jacea subsp. jacea	SC/CSR	30	
Centaurea scabiosa subsp. fritschii	C/CR	90	
Centaurea triumfettii	CR	20	
Appendix 1: A list of 143 plant species recorded in 62 relevés of dry grasslands from calcareous (30 relevés) and
silicicolous (32 relevés) geological substrates. Species values are percentage frequencies.
(*) Data from look-up table with CSR types for 1000 European species (source f. G. Hodgson, UCPE Sheffield).
Priloga 1: Seznam 143 rastlinskih vrst zabeleženih v 62 popisih suhih travišč na apnenčasti (30 popisov) in silikatni
(32 popisov) geološki podlagi. Vrednosti ustrezajo frekvencam pojavljanja vrst v skupinah popisov
(*) Podatki, ki smo jih povzeli iz tabele s CSR tipi za 1000 vrst Evropske flore (vir f. G. Hodgson, UCPE Sheffield).
Species	CSR plant strategy	Calcareous	Silicicolous
			
Chamaecytisus supinus	SC/CSR	33	
Chamaespartium sagittale	S/CSR	10	
Cirsium pannonicum	CR	70	
Cruciata glabra	S/SC	23	13
Dactylis glomerata	C/CSR	50	
Deschampsia caespitosa	SC		16
Dianthus carthusianorum	SC	63	
Dorycnium germanicum	CR/CSR	17	
Euphorbia cyparissias	CSR	60	
Euphorbia verrucosa	S/SC	63	
Euphrasia stricta	CR/CSR		6
Festuca rubra agg.	CSR		50
Festuca rupicola	S/CSR	87	
Galium mollugo	C/CSR	13	
Galium verum	SC/CSR	40	
Genista januensis	CS*	77	
Gentiana cruciata	CR		19
Gentiana pannonica	CR		22
Gentiana utriculosa	SR/CSR	20	
Gentiana verna subsp. tergestina	SC	20	
Gentianella germanica	CSR*	20	
Geranium sanguineum	C/SC	33	
Globularia cordifolia	SC	10	
Globularia punctata	C/SC	80	
Gymnadenia conopsea	S/SR*	40	44
Helianthemum ovatum	SR/CSR	93	
Hieracium aurantiacum	CR		28
Hieracium bauhinii	C/CR	30	
Hieracium laeviculae	CR		41
Hieracium pilosella	SC	17	
Hippocrepis comosa	SC	73	
Homogyne alpina	CR		47
Hypericum montanum	SC/CSR		6
Hypericum perforatum	SC		13
Hypochoeris maculata	C/CR	53	
Hypochoeris uniflora	CR		25
Inula salicina	CS*	17	
Knautia drymeia	CR	50	
Koeleria pyramidata	S/SC	100	
Laserpitium siler	C/SC	23	
Leontodon helveticus	R/CR		47
Leontodon hispidus subsp. danubialis	CR	37	
Leontodon incanus	SC	73	
Leucanthemum vulgare	C*	40	
Leucanthemum ircutianum	CR		9
Lilium martagon	CSR*	10	
Linum catharticum	CR	67	
Linum viscosum	CS*	10	
Lotus corniculatus	SC/CSR	77	
Luzula campestris	S/CSR	17	41
Species	CSR plant strategy	Calcareous	Silicicolous
			
/uzu/a /uzu/o/'Ges	SC		41
/uzu/a p/'/osa	SC/CSR		44
/uzu/a s\/vaf/'ca	SC/CSR		38
L\cKn/'s I/os-cucu//	CR		38
0eG/'cago /upu//'na	R/SR	17	
0e/amp\rum prafense	CR/CSR		75
0o//n/'a caeru/ea	SC		6
NarGus sfr/'cfa	S/CSR		100
OrcK/'s mor/'o	S/SR	13	
OrcK/'s fr/'Genfafa	CSR*	33	
OrcK/'s usfu/afa	CSR*	23	
PeuceGanum cervar/'a	C	10	
PeuceGanum oreose//'num	C/SC	83	
PK\feuma orb/'cu/are	SC	30	
PK\feuma sp/'cafum	C/CR		6
P/'mp/ne//a sax/'fraga	CR	47	
P/anfago /anceo/afa	CSR	83	
P/anfago meG/'a	CR	90	
P/afanfKera b/Yo//a	R/CR	10	
Po/\ga/a cKamaebuxus	CS*	23	
Po/\ga/a comosa	S/SC	90	
Po/\ga/a vu/gar/'s	SC/CSR	13	6
Po/\gonafum oGorafum	CR	13	
Pofenf/'//a erecfa	S/CSR	27	100
Pr/'mu/a vu/gar/'s	CSR*	33	
Prune//a granG/I/ora	CR/CSR	43	
Prune//a /ac/'n/'afa	CR	27	
Prune//a vu/gar/'s	R/CR	17	
PseuGorcK/'s a/b/'Ga	R/CR		13
Pu/saf/'//a granG/'s	CSR*	10	
Ranuncu/us acr/'s	CSR		9
Ranuncu/us bu/bosus	SR	43	
Ranuncu/us nemorosus	CR	33	
RK/'nanfKus g/ac/'a//'s	CR	57	
RK/'nanfKus m/'nor	SR/CSR	10	
RK/'nanfKus pu/cKer	CR		6
Sa/v/'a prafens/'s	CR	50	
Sangu/'sorba m/'nor	SC	97	
Scab/'osa co/umbar/'a	CSR*	17	
Scab/'osa K/aGn/'N/'ana	CR	53	
Scab/'osa fr/'anGra	CR	63	
S/'/ene nufans	S/CSR	40	
S/'/ene vu/gar/'s	CSR*	20	
So//'Gago v/'rgaurea	CR		59
SfacK\s recfa	SC	37	
Sfe//ar/'a gram/'nea	CR		6
7eucr/'um cKamaeGrys	SC/CSR		6
7Ka//'cfrum m/'nus	S/CSR	13	
7Kes/'um bavarum	CSR*	60	
Species	CSR plant strategy	Calcareous	Silicicolous
			
Thlaspi praecox	SC	33	
Thymus pulegioides	SC/CSR	60	
Tofieldia calyculata	CS*	13	
Trifolium montanum	SC	83	
Trifolium pratense	CSR	17	
Vaccinium myrtillus	S/SC		66
Vaccinium vitis-idaea	S/SC		69
Veratrum album subsp. album	CR		50
Veronica chamaedrys	CSR	10	6
Veronica jacquinii	SC	63	
Viola canina	CSR*	13