Deposition of solid waste in different tides on the beaches of Santos- SP, Brazil Amanda Aparecida Carminatto, Carlos Matuck, Edineia Farraboti, Fabiola Andrea Chofard Adami, Janaina Alves Klein, Maria das Graças Freitas dos Santos, Walter Barrella

Abstract

Solid waste deposited in the intertidal zone on the beaches of Santos, SP-Brazil, was characterized and quantified. Beaches are commonly impacted by the deposition of rubbish deliberately discarded in this environment by the population and by marine litter that is brought to the beach through the natural movement of the tides. The methodology was applied to an area of ​​33 thousand square meters, in the summer season, high season and neap tide. Two samplings were carried out, one at low tide and the other at high tide. The amount of plastic waste found results in a negative impact on the sustainability of coastal and marine resources. Through statistical tests of the collected data, the absolute differences and the sum of the abundance of each item and on each of the beaches sampled were evaluated, and similarities and dissimilarities between them were identified through cluster analysis. The presence of waste in abundance on the beaches studied was verified and its distribution was measured under different conditions. The Bray Curtis index and the Kruskall Wallis analysis were used for these analyses, and three similar groups of distribution of this waste were identified, which shows, in addition to the waste deliberately discarded on the beaches, the influences of the hydrodynamic movement between the estuarine region and the coast, worsening deposition. This discusses differences between beaches, the waste found at high tide and low tide, the interference of competent bodies for local action and the awareness of residents and tourists.