Dispersão de sementes por formigas no Brasil: tendências, lacunas e impactos das mudanças no uso da terra

Abstract

Brazil is the country with the greatest biodiversity in the world, however the loss of species caused by the increase in anthropic modifications is increasingly alarming. Ants participate in several ecosystem functions and are identified as important seed dispersers, which may contribute to mitigating the loss of large seed dispersers in anthropized landscapes. Empirical evidence demonstrates negative impacts of anthropic disturbances on ant diversity and on seed dispersal. However, there is an urgent need for studies that include what has been done so far to support conservation strategies for this function. In addition, it is necessary to use tools that assess not only the impacts on species diversity, but also more specific aspects, such as the distribution of habitat affinity groups. In this way, it is also possible to evaluate other aspects of the functions performed by the species. In this sense, we made an overview of what has been evaluated about seed dispersal by ants in Brazil. We subsequently used this extensive database and information to assess the effect of land use changes on the distribution of ant habitat affinity groups and on the ecosystem function of seed dispersal. Thus, this thesis presents two original chapters organized as manuscripts to be sent to scientific journals. In the first chapter we carried out a systematic review to investigate the role of ants on seed dispersal in Brazil. In the second chapter, we elaborated a list of ant species that occur in Brazil and classified them according to their habitat affinity. Subsequently, we verified the effect of land use modifications on the frequency of species in ant habitat affinity groups and on the ecosystem function of seed dispersal. In this thesis, we provide crucial information for the development of monitoring strategies for both assemblages and ecosystem functions performed by ants. Thus, this thesis proves to be highly relevant for a deeper understanding of the impacts caused on ecological communities, which is crucial for directing conservation strategies.