PARENT SESSION
Contributed Oral Session 6: Biodiversity: Management, Theory, and Techniques
Monday, August 8, 8:00 AM - 11:30 AM, Meeting Room 516 D, Level 5, Palais des congrès de Montréal

Determinants of arthropod diversity in farming landscapes: A multi-scale assessment.

Aviron, Stéphanie^*,1, Jeanneret, Philippe¹, Schüpbach, Béatrice¹, Pfiffner, Lukas², Walter, Thomas¹, Herzog, Felix¹, ¹ Agroscope FAL Reckenholz, Zürich, Switzerland² FIBL, Frick, Switzerland

ABSTRACT- To understand the relationships between biodiversity patterns and the environment, analysis must be conducted at multiple spatial scales. In farming landscapes, species diversity depends not only on habitat quality and local management, but also on the landscape pattern, which is linked to farming type and intensity. Moreover, species respond to landscape features at different scales depending on their ecology and dispersal ability. In this study, we investigated the effect of factors at the local and landscape scales on the diversity of three arthropod taxa (spiders, carabid beetles and butterflies) in three regions with contrasted landscape pattern and farming intensity. The respective impacts of (i) habitat type/management, (ii) landscape context at different spatial scales and (iii) regional localisation (the region) were tested on arthropod species richness and species assemblages. Habitat type/management and region had the strongest influence on arthropod diversity. The region factor reflects, among others, an influence of farming type and intensity and of landscape pattern at the regional scale as well as of biogeographic situation. Landscape context did not affect the number of arthropod species, but had a significant effect on species assemblages. Spider, carabid and butterfly assemblages did not respond to landscape pattern at the same spatial scales. Butterflies were more closely correlated to the amount of semi-natural habitats at large scale. In contrast, carabid beetles and spiders reacted to landscape context at both small and large scales, due to contrasted life-history traits of species. To conclude, our results show that habitat management locally, farming intensity and landscape pattern at a large scale are determinant factors acting specifically on the arthropod taxa. Landscape features are also important, but are relevant factors only at specific spatial scales depending on the studied taxa.

Key words: spatial scale, landscape features, farming intensity, arthropod diversity