Legal reserves ensure alpha and beta ant diversity in highly modified agricultural landscapes

Abstract

To preserve biodiversity, the Brazilian law postulates that rural properties must keep a percentage of native vegetation cover, denominated as “Legal Reserve” (LR). Recent political efforts are being made to disoblige the farmer to keep the LRs. In this study we evaluated the role of LRs in ensuring the ant biodiversity on LRs and soybean plantations. Ants were collected in 42 landscapes within Amazonian forests and Cerrado savannahs and the transition vegetation between them. In each landscape, sets of pitfall traps were placed in a paired design, in the Legal Reserve area and in the adjacent soybean cultivation matrix. As expected, the number of species was extremely lower on soybean plantations. Despite richness, we observed strong turnover between the LRs and plantations. The landscape types on which the Legal Reserve was inserted did not influence the number, but did influence the composition of species. Also, the similarity among samples decay with geographic distance only on LRs. Our results show the importance of the maintenance of Legal Reserve areas for the ants and associated biodiversity in agro-ecosystems. This fact reinforces the need to preserve the Legal Reserves as described in Brazilian law.

Keywords

• Ant assembly
• Ecosystem Services
• Habitat loss
• Landscape Ecology
• Pitfalls trap.