RESUMO
Cagarras Islands Archipelago, a no-take MPA in Southeast Brazil, was designated as Natural Monument (MONA Cagarras) and, more recently, recognized as Hope Spot for biodiversity conservation. This study aimed to assess plastic contamination by analyzing marine litter and microplastics in MONA Cagarras and surrounding waters. Marine litter (34.12 kg) was caught by artisanal fishermen in MONA Cagarras proximities, and plastics represented â¼79 %. Personal hygiene items and strains of hair were found, suggesting sewage-derived contamination from Ipanema SSO. Microplastics were detected in MONA Cagarras surface waters. Fragments and black particle were the most frequently found microplastic shape and color, respectively. µ-FTIR analysis identified, in descending order of occurrence, polystyrene-PS, polyethylene-PE, polyvinyl chloride-PVC, polypropylene-P, and polyamide-PA. Our integrated results of macro and microplastic contamination highlight an issue of effective conservation and health of marine biodiversity in MONA Cagarras and surrounding waters and a concern for better management of Brazilian MPAs.
Assuntos
Biodiversidade , Monitoramento Ambiental , Plásticos , Esgotos , Poluentes Químicos da Água , Brasil , Plásticos/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Microplásticos/análise , Ilhas , Conservação dos Recursos NaturaisRESUMO
Angra dos Reis can receive up to 1.3 million tourists in the summer season. The lack of an adequate sanitary system makes sewage contamination a growing concern in Ribeira Bay, Angra dos Reis, Brazil. This study aims to investigate the seasonal variation of faecal indicator bacteria (FIB) and abiotic variables in Itanema cove situated within Ribeira Bay. Despite the seasonal population increase (>80 individuals) and the absence of an integrated sanitary system, our results indicate that Itanema is still a stable estuarine environment. From 2017 to 2019, the mean salinity was 27.91, pH was 7.82, and water temperature was 25.01 °C. However, the FIB number was 105, suggesting the absence of sewage treatment in Itanema's outfall. Following current conservation status, baseline studies are mandatory for background references of endangered coastal areas such as Itanema cove. These studies are crucial for future governance decisions and sustainable tourism implementation in Angra dos Reis.
Assuntos
Bactérias , Água do Mar , Brasil , Fezes , Humanos , EsgotosRESUMO
The dark false mussel Mytilopsis leucophaeata occurs as non-native species in Asia, Europe and South America. Despite the low population density usually found in its native range, M. leucophaeata forms dense clusters in newly invaded areas which lead to impacts on local organisms and environment. Some of the impacts of non-native species on newly colonized areas may be positive. However, despite the empirical evidences of increase in water transparency by freshwater dresseinids, the hypothesis that dark false mussel enhances the quality of brackish water has never been tested so far. Thus, the present study aimed to determine M. leucophaeata impacts on the water quality of a nutrient-enriched coastal lagoon by (1) analyzing a historical water dataset for pre- and post-invasion at Rodrigo de Freitas Lagoon (Brazil) and (2) experimentally testing dark false mussel direct effects on water quality. Historical field data evidenced significant lower phytoplankton abundance and chlorophyll a, and higher water transparency for the post-invasion period. These pattens were also supported by time-series analyses, which detected a decreasing trend for total coliforms density and an increased trend for dissolved oxygen over time. Moreover, time series indicated a gradual increase in lagoon water level with time, but none or minor changes were evidenced for floodgates operation routine, meteorological variables, and the frequency of sewage input. In microcosms, M. leucophaeata was effective to increase water transparency and decrease E. coli densities. The combination of field and laboratory data partially supported the hypothesis that M. leucophaeata invasion promoted an improvement in lagoon water quality, but increased phosphorus availability through excretion in microcosm assays. Management of dark false mussel populations seems to be a potential strategy for water quality improvement within already invaded systems where high sewage-enriched effluents are released. However, as non-native species often unbalance ecological relationships and functioning of the invaded ecosystems, new introductions of M. leucophaeata must be avoided.