Os manguezais são um dos ecossistemas mais importantes do planeta, no entanto o seu potencial é afetado pelas atividades humanas intensas e pela expansão urbana. Um dos principais impactos sobre manguezais é a disposição de resíduos sólidos de origem antropogênica. O objetivo deste trabalho foi realizar uma avaliação da poluição por resíduos sólidos em duas áreas de manguezais associadas ao estuário do rio Potengi - Natal (RN), estabelecendo sua relação com a localização e os níveis de utilização e exploração dessas áreas. Foi realizado um diagnóstico das áreas através de observações mensais e entrevistas informais a fim de se determinar as características e os usos predominantes. Para avaliação dos resíduos sólidos, foram demarcadas, em cada área, 3 parcelas de 50m2 cada. As amostragens foram realizadas mensalmente durante 06 meses, três do período chuvoso e três do período seco. Foram analisados, além da abundância, a localização no ambiente, a classificação segundo a constituição (plástico, metal, vidro, papel, madeira, tecido e orgânico) e, quando possível, sua fonte mais provável (usuários locais, doméstica, mista e pesca). As áreas apresentaram características ambientais e de uso completamente distintas. Nos seis meses de amostragem de resíduos sólidos, foi registrado um total de 1.381 itens, 77 para a área 1 e 1.304 para a área 2. Em ambas as áreas, a categoria mais frequente de resíduos foi o plástico. Também em ambas as áreas, os resíduos sobre o sedimento foram maioria. Na área 1, a fonte predominante foi a mista, contribuindo 49% do total de itens, enquanto que, na área 2, 57% dos resíduos identificados provavelmente se originaram nos usuários locais. A grande quantidade de resíduos encontrados na área 2 demonstra que a área precisa de planejamento e infraestrutura para receber turistas, com a instalação de lixeiras para coleta de resíduos sólidos em quantidades suficientes e educação ambiental com comerciantes, usuários e guias turísticos.

Mangroves are one of the most important ecosystems on Earth; however, its potential is affected by intense human activities and urban sprawl. The increase of the populations in localities near the coast has been pressing this and other natural biological systems. One of the main impacts on mangroves is solid waste disposal from anthropogenic origin. Studies on the impact of solid waste in coastal regions are quite widespread and well known, but are generally made with a focus on the beaches or in the marine environment, while research on mangroves are quite scarce. The estuary of Potengi river (Natal-RN) has a great environmental and socio-economic importance; in its mangroves, about 1,200 families survive by collecting crustacean and shellfish. According to local studies, the estuary is affected by intense changes that occurred during the last century, mainly due to disorderly growth of Natal city. The objective of this work was to carry out an assessment of solid waste pollution in two mangrove areas associated with the estuary of the Potengi River, establishing its relationship with the location and levels of use and exploitation of these areas. A diagnosis of the areas was carried out through monthly observation, to determine their main characteristics and types of use. For a detailed survey of the main uses were made contacts and informal interviews with local residents, fishermen, tourists, traders and government agencies. For evaluation of solid waste were demarcated three transects of 50m2 each in each area. Samples were taken monthly for 06 months (three of the rainy season: May, June and July, and three of the dry season: September, October and November); the abundance and location in the environment (sediment or suspended), were analyzed. The classification according to the constitution (plastic, metal, glass, paper, wood, fabric and organic) and when possible, their most likely source (local users, domestic, mixed and fishing) also were determined. The areas showed environmental characteristics and use completely different. In the Area 1 the access is difficult because it is done through a dirt road that enters a very narrow trail bordered by thick vegetation and with erosion process. The mangrove presents good condition, with vegetation preserved and used only by locals. In the Area 2 there is only a narrow strip of mangrove totally limited in their faces west and south by urban structures. Besides the paved lanes that allow the arrival to the area, providing parking and stalls for selling crafts and food, the place has an access that was opened with the removal of mangroves, and built on a high rock allowing the arrival of hundreds of tourists to Reis Magos Fort. In the six months of sampling, was recorded a total of 1,381 items of solid waste, 77 for Area 1 and 1304 for Area 2. Area 2 had approximately 17 times more items than Area 1, however, in both areas, the most frequent category of litter was plastic. Also, in both areas, litter on the sediment was majority. In the area 1 the predominant source was mixed contributing 49% of the total items, while in area 2, 57% of the residues identified, probably originated in the local users. The large amount of residues found in the area 2, demonstrates that the area needs planning and infrastructure to receive tourists, with the installation of bins for collect solid wastes in sufficient quantities and environmental education with tradespeople, users and tour guides.