Caracterização e avaliação da qualidade ambiental do estuário Ponta do Tubarão (RN) com base na água, sedimento e macroalgas marinhas

Abstract

Estuaries and coastal zones are dynamic systems of great environmental, economic and social importance. All over the world these areas are becoming increasingly impacted because ofthe anthropogenic activities caused by rapid economic growth and urbanization. Thisresearchwas carried out in the Tubarão estuary, which is located in the northerncoast of Rio Grande do Norte, Brazil. The estuary area is part of the Ponta do Tubarão Sustainable Development Reserve (RDSEPT). In the surroundings of this conservation unit,several economic activitiesare developed,such as fishing, agriculture, aquaculture, saline and oil industry, besides ecological tourism. Considering the ecological, economic and social importance of this ecosystem, a study was runto characterize and evaluate the environmental quality of the Tubarão estuary through analysis of nutrients (N and P) and heavy metalsin water, sediment and seaweeds (Gracilariopsisand Hypnea). The research carried out for this purpose is composed of three chapters: (1) in the first chapter the dynamic of nutrientswas investigated to understand the biogeochemical processes and to identify possible anthropogenic impacts in this tropical ecosystem; (2) the second chapter of the thesisanalyzes and points out which compartments(water, sediment and seaweeds) that hold the largest concentration of heavy metals and finally thethird chapter (3) which examines the RDSEPT extractivists’ environmental perceptionand aims to measure the population's understandingof reserve environmental issues. The results obtained in the different chapters provide important information on the state of environment of the Tubarão estuary and maycontribute tothereservemanagement.