Effects of agroecosystem landscape complexity on small mammals: a multi-species approach at different spatial scales

Context The effect of landscape complexity on biodiversity is an important topic in landscape ecology, and spatial scale is key to understand true species-landscape relationships. Objectives We assessed the effect of landscape complexity on the occurrence of small mammal species and species richness at different spatial scales in an agroecosystem of central Argentina. Methods We performed two capture-recapture samplings in 50 sites with different landscape complexity covering a ~ 452 km 2 area. We used a multi-species analysis following a Bayesian approach. We modeled species occurrence as a function of landscape complexity (estimated through the Shannon habitat diversity index) at six spatial scales. Results We found that the occurrence probability of species that are favored by agriculture intensification increased with the decrease of landscape complexity, whereas that of species dependent on natural habitats decreased. Some species occurred over the whole range of landscape complexity, one species was only present in the simplest landscapes and the others occurred at intermediate and high values of landscape complexity. Species richness increased with landscape complexity. On average, our results suggest that landscape complexity is perceived by small mammals at a spatial scale of 150-200 m. Conclusions Landscape heterogeneity is a key factor to maintain biodiversity and species persistence in agroecosystems. An important finding of our study is that a complex landscape at 200 m (16 ha) spatial scale would benefit most small mammal assemblage species. This result would be key to define management strategies for biodiversity conservation in agricultural landscapes of central Argentina.