Agricultural land-use intensity and its effects on small mammals in the central region of Argentina

Abstract

Agriculture intensification is one of the main threats to biodiversity in agricultural systems. The effectiveness of conservation strategies in these systems depends mainly on the compromise between biodiversity conservation and agricultural land use. The aim of this study was to assess the effect of land-use intensity, characteristics of linear habitats (field borders) and their surrounding fields (landscape) on small mammal richness and abundance in agricultural systems of Argentina. In autumn 2009, we performed a removal sampling in 60 traplines located in the field borders of high or low land-use intensity regions. In traplines under high land-use intensity we found seven species while under low land-use intensity we found ten. Characteristic species of grasslands and woodlands such as Monodelphis dimidiata, Thylamys pallidior, Necromys lasiurus and Graomys griseoflavus were only captured in traplines under low land-use intensity. Higher numbers of Calomys musculinus species (habitat generalist) were observed under high land-use intensity while Akodon azarae and Oxymycterus rufus species, known as habitat specialists, were more frequently found in the low land-use intensity region. Border width and height, as well as land use of both sides of the border, were major variables for explaining small mammal abundances. Our results suggest that conservation of wide field borders with characteristics similar to those of natural habitats would be crucial for sustainable management of Pampean agricultural systems which hold high richness and abundance of small mammal species.