Effect of forests structure and small-scale environmental conditions on the community of epigeic arthropods (Carabidae, Araneae)

Forests are more than a stand of trees in the landscape. They represent a complex, functional system of interacting and often interdependent biological, physical and chemical components (Kimmins 1997). In the past, complex interactions were increasingly recognized over time as food webs, abiotic processes and biotic feedbacks since then defined as the forest ecosystem. Trees grow in a world of multitrophic interactions (van der Putten et al. 2001). One component of this functional system is represented in several aspects by spiders and insects, as they contribute considerably to the biodiversity and ecosystem functioning in forest habitats (Watt et al. 1997). There is knowledge on the community composition of several forests of different stand type or tree species composition referring to soil dwelling arthropods. Moreover, studies often highlight the orientation of single arthropod species on abiotic factors or the composition of species assemblages in case studies; these represent ecologically well described groups that can be used as indicators of habitat quality (Pearce and Venier 2006; Cardoso et al. 2004). Evidence on the scale of interactions between the species and their environment are rare. This applies particularly to examples based on fine spatial and temporal scales.:Zusammenfassung 1 Summary 4 Chapter 1 General Introduction 7-19 1.1 Arthropods as a permanent component of forest ecosystems 7 1.2 Spiders and carabids in forest ecosystems 10 1.3 Are spiders and carabids in ecosystems dispensable? – functional diversity in natural antagonists 13 1.4 Objectives 20 Chapter 2 Influence of environmental parameters on small-scale distribution of soil-dwelling spiders in forests: what makes the difference, tree species or microhabitat? 23 2.1 Abstract 23 2.2 Introduction 24 2.3 Methods and materials 25 2.4 Results 32 2.5 Discussion 45 2.6 Conclusions 51 Chapter 3 Microhabitat heterogeneity in temperate forests: is distance to stems affecting ground-dwelling spider communities? 61 3.1 Abstract 61 3.2 Introduction 62 3.3 Materials and Methods 63 3.4 Results 68 3.5 Discussion 77 Chapter 4 The impacts of seasonality, forest type and succession on the community structure of temperate-forest ground beetles. 88 4.1 Abstract 88 4.2 Introduction 90 4.3 Methods and materials 92 4.4 Results 98 4.5 Discussion 113 4.6 Conclusions 120 Chapter 5 Is the age of forest habitats affecting the reproductive rate of generalist predatory ground beetle species? 129 5.1 Abstract 129 5.2 Introduction 131 5.3 Methods and materials 133 5.4 Results 138 5.5 Discussion 150 5.6 Conclusions 153 Chapter 6 General Discussion 161 6.1 Management effect 169 6.2 Future prospect 170 Liste der Veröffentlichtungen 173-174 Danksagun