Scale-dependent correlates of reptile communities in natural patches within a fragmented agroecosystem

Abstract

Studying biodiversity in light of increased fragmentation in agroecosystems requires the understanding of scale-dependent and multi-scale determinants of various community measures. In a heterogeneous agro-landscape, we aimed to understand whether: (1) Reptile communities are affected by a certain variable that belongs to a particular scale, or, by a combination of variables at different scales, and (2) Reptile community measures are affected differentially by variables related to different scales. We sampled reptiles in three 12.6 km2 land units by using 100 × 50 m plots within 27 natural habitat patches. We collected spatial information of different scale-oriented physical and biotic variables and analyzed changes in community measures at four scales—landscape, land unit, patch and plot—by using the model selection approach based on the AICc. Multiple-scale, rather than single-scale models, best explained all three community measures, indicating that the reptile community structure is highly affected by ecological processes operating at different scales, from the local up to the entire landscape scale. However, abundance, species richness and diversity were affected dissimilarly by different combined determinants and at different scales. Reptile biodiversity at our heterogenous agro-landscape is highly influenced by determinants of multiple scales, where each scale has its contribution to the overall obtained pattern. Number of individuals and species richness respond differently to various processes, depending on the scale at which these processes operate. Agro-landscapes retain the complexity of ecological systems and can serve to maintain natural communities through land sharing practices.