The pivotal role of land cover around forest fragments for small-mammal communities in a Neotropical savanna

While harboring the bulk of the planet's biodiversity, tropical ecosystems have experienced intense land conversion for agriculture. Studies examining the impacts of land-use change on tropical biodiversity have primarily focused on forest cover loss but have overlooked the ecological potential of habitats surrounding forest fragments to modulate biodiversity loss. We examined whether small-mammal communities changed with the land cover surrounding forest fragments, and how functional traits affected responses to land cover. Small mammals were sampled in the Brazilian Cerrado using live-trap transects. Three landscape types were identified according to the surroundings of the transects (within 750-m-radius buffers): forest- (=50% forest cover), pasture-, and crop-dominated landscapes (<50% forest cover, with predominance of pastures or crops, respectively). We examined the composition of functional traits across landscape types and used abundance models to analyze the response of small-mammal communities to land cover. From forest-dominated to pasture- and crop-dominated landscapes, the abundances and/or species richness of the largest, forest-specialist, frugivorous/granivorous, and terrestrial species decreased. In forest-dominated landscapes, abundances and species richness were slightly affected by land cover surrounding forest fragments. In pasture- and crop-dominated landscapes which represent the less-preserved landscapes, increased proportions of native forests, open formations, and, to some extent, pastures, supported the increased abundance of small mammals. Land cover surrounding forest fragments is critical for maintaining the diversity of species and functional traits within small-mammal communities. Our results emphasize the need to maintain native vegetation in human-modified landscapes to maintain biodiversity and ecological functions.

Automated summary

Tropical ecosystems, which harbor the highest biodiversity on the planet, are facing significant land conversion for agriculture. Previous studies have focused on the impacts of forest cover loss on tropical biodiversity, neglecting the role of habitats surrounding forest fragments. This study found that the composition and abundance of small-mammal communities are closely related to the land cover surrounding forest fragments, emphasizing the importance of maintaining native vegetation in human-modified landscapes.