Microplásticos do plâncton na porção norte da APA Costa dos Corais (Tamandaré, Brasil)

Abstract

Microplastics are particles smaller than 5 mm and can be broadly classified as: filamentous, hard fragments and soft fragments. These particles are among the main current solid contaminants in the marine environment. Such fragments can be released into the environment in different ways, such as degradation itself through biotic or abiotic factors. After being degraded, these particles can be suspended in the water column, thus being able to be ingested by organisms, especially filters at the base of the food chain. The work aims to characterize the plankton microplastics in the waters that bathe the northern portion of the Costa dos Corais Environmental Protection Area, in Tamandaré (PE), aiming at the evaluation of three planktonic compartments in the area (estuarine plume, in the reefs and in the bay ). Samples from 4 campaigns carried out between Sep / 2017 and Mar / 2018 were analyzed, aiming to sample periods with different rainfall regimes, always at low water (to better establish the influence of estuarine plumes). The analyzed microplastics were quantified and classified according to type. To confirm the visually screened microplastics, tests were performed with nitric acid (HNO3). The results show that there is a higher incidence of filamentous microplastics (12 ± 13 mp / m³), compared to other types. The presence of filamentous microplastics reached an average density of 16.08 ± 16.22 mp m³ in the plume, in the dry period, and in the rainy period it had an average of 21.62 ± 20.77 mp m³ in the reefs. . The densities of filamentous microplastics were significantly different between points (plume, bay and reefs). In each period, even with this variation between the points, the data indicate that there was a variation between the points, but if compared to other studies, the variation is not significant, although the bay has shown variation in relation to the other areas. In the present study, the seasonal period did not have a significant influence on the increase in the presence of microplastics in the studied points, even though microplastics are common in estuarine systems in several parts of the world, the fact that there were no seasonal differences in the studied points ( it was expected that during the rains the occurrence of microplastics would be higher) due to the insertion of the Ilhetas and Mamucabas estuaries in a protected region (APA Guadalupe and ReBio de Saltinho).