Sandy beach pollution: pollutants distribution and levels on benthic biodiversity

Abstract

For decades, marine and coastal ecosystems have been impacted by pollution produced by anthropogenic activities, mainly related to agriculture, industry and urbanization. Most of the substances released on natural systems represent critical threats due to their persistence, toxicity, bioaccumulation and trophic transfer capacity. For this reason, efforts to evaluate and map pollutants levels and their associated impacts on biodiversity and human health are a crescent need for the implementation of effective management strategies. This kind of assessment is especially relevant in sandy beaches, once human populations depend on resources and essential ecosystem services provided by these environments. Nevertheless, little is known about how pollutants affect sandy beaches and their biota, mainly because sediment samples usually do not allow this type of analysis in these environments. In this context, the aims of this study are to investigate the concentration of heavy metals, organic pollutants and microplastics in benthic organisms of sandy beaches and map pollution levels on the Northern Coast of São Paulo State (NCSP). For this purpose, adult individuals of Donax hanleyanus and Emerita brasiliensis will be used as biomonitors along 48 beaches of the region. Tissue of the organisms will be used in the chemical analyses to determine the concentrations of each pollutant. The total concentration of each pollutant group will be individually evaluated using repeated measures ANOVA to investigate potential differences among beaches and between both species. Lastly, the obtained data will be integrated in multivariate analyses to derive conclusions about the current status of pollution in sandy beaches of the NCSP. Maps will be produced to understand variations in the pollution levels among the different beaches, which will be related to potential sources of emission and discussed in terms of the existence or need of public policies in the region. Thus, the present study expects to identify which beaches receive higher amount of pollutants and therefore require major attention from decision makers for conservation, monitoring and management actions. (AU)