Ábrahám Levente (szerk.): Válogatott tanulmányok VI. - Natura Somogyiensis 19. (Kaposvár, 2010)
SALAMON-ALBERT É., HORVÁTH F., & ORTMANN-AJKAI A.: Climatic conditions and habitats in Belső-Somogy, Külső-Somogy and Zselic as vegetation-based landscape regions II. Temperature and precipitation sensitivity of woodlands
52 NATURA SOMOGYIENSIS ent spatial scales connected with some vegetation classification according to bioms, continents, countries and regions (OZENDA and BOREL 2000, HOSSEL et al. 2003, PIOVESAN et al. 2005, THOMPSON et al. 2005, ATTORF. et al. 2007, THOMPSON et al. 2008). Need for smaller-scale studies are expressed by more and more authors currently (e.g. LINDNER et al. 2010), but conclusions derived from scientific results based on large scale studies have to be applied with caution. Distributions may not match climate exclusively, because of biotic interactions, adaptive evolution, dispersal limitation and historical chance that each or all could exist behind the phenomena (BEALE et al. 2008). Bioclimatic indices connected to vegetation data are widely used for interpretation of species or habitat distribution or suitability in vegetation science under different climate scenarios (HOSSELL et al. 2003, BEAUMONT et al. 2005, HUMANS et al. 2005, ATTORRE et al. 2007, Czúcz et al. 2009). They were originated from the monthly temperature and precipitation data in order to generate more biologically meaningful variables, representing annual trends, seasonality and extreme or limiting environmental factors (HIJMANS et al. 2005). Climate has been shown to be a significant environmental feature in determining vegetation distribution and classification for European scales, especially in woody habitat types. It is important that we are able to describe current habitat distribution in a reliable way according to climate surface and quantify their climate envelope by a climatic niche concept. It will be reassuming used for analysing and detecting functional landscape diversity and climatic sensitivity of woodlands, to be able to understand the impacts of temperature and precipitation at different scales. Habitat distribution models often built up on bioclimatic variables as abiotic predictors according to niche stability and evolution (GUISAN-ZIMMERMANN 2000, ZIMMERMANN et al. 2010). Habitat distribution models (HDMs) derived from species distribution modelling (SDMs), can evaluate range of occurrence from environmental point of view, leading towards habitat adaptation under certain climatic conditions. Novel analyses, e.g. connecting distribution models with other ecological phenomena, can provide novel capacities for understanding specific and general drivers of ranges in occurrence. In this study our aims were to reveal 1) what the climatic range and the character of woodland distributions are, 2) what the relations between regional and habitat climate envelopes are, 3) which climate variables the most significant in woodland habitat distribution and climate sensitivity are. Material and method Study area The study area includes the territory of three vegetation based landscape regions of South Transdanubia: Külső-Somogy, Belső-Somogy and Zselic, covering about 5705 km 2 (570500 ha) in total (Fig 1). Their borders are defined on the basis of present zonal or dominant extrazonal or edaphic vegetation by the knowledge of local expert botanists. It is not derived from any database ( MOLNÁR CS. et al. 2008) and differs from the previously used, country-wide, geography-based landscape divisions (e.g. MAROSI and SOMOGYI 1990). Elevation varies in a moderate range from lowlands (96 m a.s.l.) to hills (300 m a.s.l.), average altitude is 161 m a.s.l. Long-term annual precipitation varies between 562 and 753 mm, the average is 674 mm, the annual temperature varies between 9.8 °C and 11.3 °C, the average is 10.8 °C. Studied regions are at the intersection of three climatic areas: from west as the atlantic, from east as the continental and from south as the mediterranean, that can influence the general climatic pattern. According to the main
