RESUMO
Large gaps in reef distribution may hinder the dispersal of marine organisms, interrupting processes vital to the maintenance of biodiversity. Here we show the presence and location of extensive reef habitats on the continental shelf between the Amazon Reef System (ARS) and the Eastern Brazilian Reef System (ERS), two reef complexes off eastern South America. Formations located 20-50 m deep include both biogenic and geogenic structures. The presence of diverse reef assemblages suggests the widespread occurrence of rocky substrates below 50 m. These habitats represent an expansion of both the ARS and ERS and the closure of the only remaining large-scale gap (~ 1000 km) among West Atlantic reef environments. This indicates that the SW Atlantic harbors a single, yet heterogeneous, reef system that stretches for about 4000 km, and thus, represents one of the largest semi-continuous tropical marine ecosystems in the world.
Assuntos
Biodiversidade , Ecossistema , Animais , Organismos Aquáticos , Brasil , Recifes de Corais , PeixesRESUMO
The aim of the present study was to perform the first assessment of the abundance and classification of marine debris as well as determine the sources, transport and fate of this debris on an urbanized coast with multiple human activities. More than 80% of the marine debris was composed of synthetic materials. The beached marine debris was classified according to size. Meso-debris accounted for the highest portion of contamination (55%), followed by macro-debris (25.1%) and small debris (19.9%). Contamination by debris, such as cotton swabs (31%) and lollipop sticks (36.8%) accounted for the largest portion of the small debris class. Human recreational activities were the predominant source of debris, followed by navigation/fishing activities, domestic activities and industrial/port activities. The assessment of the predominance of human activities and the results of the model revealed a larger contribution of debris from recreational activities on nearby beaches on the small to larger scale and that rivers exert less of an influence due to the fact that they do not flow the entire year.