Nascentes de Mata Atlântica: panorama e ecologia da fauna de Oligochaeta (Annelida) e implicações para conservação

Abstract

Springs are important landscape elements due to its economic, social and ecological importance. In view of the increasing degradation of these ecosystems, added to low knowledge about their biodiversity in tropical regions, the main goal of this study is to increase the knowledge about springs in tropical regions and to provide information on the diversity and ecological aspects of aquatic oligochaetes in this ecosystem. To confirm the lack of studies in springs, specifically considering freshwater oligochaetes, a bibliographic survey has was made basead on the studies carried in a period of 30 years (1985-2015) in various continental aquatic environments around the world. The survey showed that spring are one of the least studied ecosystems, together with cave water bodies and swamps. For this study, fauna was collected, physical and chemical variables were measured, and a rapid assessment protocol (RAP) were applied at spring located in different cities of Minas Gerais State, either in Conservation Units or in public and private areas. The results showed differences among the oligochaetes species composition found in spring that rises diffusely forming a flooded area (helocrene), in comparasion to spring that forms streams (rheocrene) and that ones that forms a pond (limnocrene). Probably, it is due to the high heterogeneity of this kind of spring. We also verified that beta diversity was high at the three types of springs, suggesting that efforts to conserve these ecosystems should include many spring systems of all types. After applying RAP, this study emphasized that, besides the major numbers of spring, water have been classified as optimum also the springs located in urban areas were classified as moderate or poor, even when some of them were located in Conservation Units. This result highlights importance of Conservation Units on spring preservation, and also the vulnerability of these systems when inserted in urban environments. This study contributes not only for academic knowledge, but also for environmental management, once it points out the habitats and places that need more studies, showing the importance of preserving different types of spring systems for the maintenance of diversity. It also indicate the requirements for major inspections and the legal enforcement provisions needed, in order to avoid further transformations in the natural conditions of these systems.