A influência da dinâmica e dos diferentes usos na distribuição e origem de microplásticos no litoral da Ilha Grande, Angra dos Reis (RJ)

Abstract

The coastlines are increasingly threatened by solid waste pollution, which puts coastal environments and the populations which depend on them for their livelihoods at risk. Plastic has been the item mentioned, in increasing numbers, among solid waste. Corroborating the growing microplastic pollution, which has been mapped globally in various surveys. This work aims to build a diagnosis about microplastic pollution on the coast of Ilha Grande (Angra dos Reis, RJ) based on the understanding of the role of source areas (continental and marine) and coastal processes (waves, currents and tides) in transport and deposition of materials. In this sense, it is necessary to identify the occurrence and sources of solid waste and the role of coastal processes in the distribution of these materials. The coast of Ilha Grande is characterized as the most extensive island in the southern region of the state of Rio de Janeiro, with about 80 beaches, part of which are facing the continent and the other facing the Atlantic Ocean. A large part of this island is covered by the remaining vegetation of the Atlantic Forest, which makes up the Tamoios Environmental Protection Area (APA dos Tamoios). Local biodiversity and coastal systems have their equilibrium constantly threatened by the expansion of tourism and oil activities in the region. The population of Ilha Grande, concentrated mainly in the villages of Abraão, Dois Rios and Provetá, depends to a large extent on activities related to tourism and artisanal fishing. The methodology of this study consists of carrying out a bibliographic review on the theme, collections between the seasons (winter and summer) and laboratory analyzes for the characterization and classification of micro solid waste on 10 beaches around Ilha Grande: Grande Araçatiba, Japariz, Abraão, Abraãozinho and Pouso, located on the north face; Lopes Mendes, Dois Rios, Parnaioca, Aventureiro and Meros, in the southern sector of the island. The results obtained from the monitoring carried out in the winter of 2018 and summer of 2019 show a higher occurrence of microplastics on the beaches located on the southern edge of the island, with emphasis on the Lopes Mendes and Dois Rios beaches; on the north face, the largest amounts of microplastics were found on the beaches of Japariz and Abraãozinho. Polystyrene (styrofoam) is predominant, followed by fragments, pellets, fibers, films and plastic foams.