Global International Waters Assessment: Brazil Current, GIWA Regional Assessment 39

University of Kalmar on behalf of United Nations Environment Programme (2004)

This report presents the assessment of the GIWA region Brazil Current, including drainage basins and their associated coastal/marine zones. Three separate sub-regions have been assessed within the region: the South/Southeast Atlantic Basins, East Atlantic Basins, and So Francisco River Basin. Increased anthropogenic pressures due to economic development and urbanisation in the coastal area have polluted the water environment and caused severe impact on important ecosystems such as coastal plains and mangrove ecosystems. Significant changes in the suspended solids transport/sedimentation dynamics in the river basins due to unsustainable land use practices associated to intense deforestation and damming has caused increasing erosion of coastal zones, siltation of riverbeds, and modified the stream flows resulting in periods of water scarcity and flooding in some basins. The root causes of pollution and habitat and community modification are identified for the bi-national Mirim Lagoon Basin, a transboundary freshwater body shared between Brazil and Uruguay, and Doce River Basin that hosts biomes of global importance. Potential remedial policy options are presented.