Development of environmental effects monitoring protocol in Brazil: a fish guide study of three river estuaries

摘要

In Brazil, there are no unified and effective environmental monitoring models for bodies of water. Thus, several methodologies are used that result in information that is often difficult to compare, especially for stakeholders involved in regional water management. Studies in some countries such as Australia, Chile, the USA, and Sweden use the monitoring model implemented in Canada that was developed in the early 1990s. This model was designed to evaluate whether the current environmental regulations are sufficiently protective for pulp and paper effluents and for metal mining effluents. In this study, the Canadian Environmental Effects Monitoring methodologies were applied to three different Brazilian river basins, with the goal of constructing a framework for monitoring environmental effects. Pilot studies were carried out in the estuarine regions of the Benevente, Jucu, and Santa Maria da Vitoria river basins, which are important rivers in the state of Espirito Santo. Evaluations included fish health, bioaccumulation studies, benthic invertebrate survey, and physical-chemical analyses of water and sediment. The quality of the environments was evaluated by means of seasonal samplings and comparisons between discharge, upstream, and downstream areas. This study made it possible to identify appropriate fish species to be used in environmental effects monitoring and the environmental quality of the rivers themselves as well as knowledge and policy gaps to implement such monitoring programs in Brazil. The study raises questions about the adequacy of Brazilian environmental legislation concerning tidal rivers.