GERSON FERNANDINO DE ANDRADE NETO

This study aimed to quantify marine litter before and during the COVID pandemic found on urban touristic beaches closed to beachgoer access in northeastern Brazil. Litter identification and quantification was conducted during April, June, and August 2019, when 3583 items were sampled, and replicated during the same months in 2020, when access to the beaches studied was prohibited and a significant reduction in the amount of litter was found, 1812 items (49% decrease). Transects were used to monitor and classify litter according to its source, namely: autochthonous (litter that was locally discarded) and allochthonous (litter from other sites and sources). All beaches were classified as “very clean” and presented a smaller amount of litter during the beach closure period. The highest total marine litter reduction between the periods studied was 83%, while autochthonous litter in particular showed the most significant reduction, 88%. The comparison between the quantity and type of litter found in both periods showed greater specific anthropic pressure from beach users.

Continuous input of plastic litter in ocean and coastal environments achieved alarming levels that are exposing new settings in natural systems. While novel plastic debris pollution, with rock-like appearance, has been reported worldwide, fundamentally geological analyses are still lacking. We surveyed the first occurrence of multiple associated plastic debris on a single outcrop located in a remote site (Trindade Island, SE Atlantic Ocean). Even though all plastic debris forms consisted of polypropylene and polyethylene, through a sedimentary approach (cross section, macro, and micro analyses) distinct types were identified. We detected plastiglomerates, geogenic analogous to conglomerates, divided into in situ and clastic types, and formed over beach sediment. We identified plastistones as a new type with homogeneous composition (lacking incorporated materials), geogenic-looking igneous rocks, divided into in situ and clastic types, and formed over rock surfaces. We linked pyroplastics, geogenic analogous to clasts, to clastic plastiglomerates/plastistones, therefore representing clastic types of plastic debris forms. This association was correlated in a depositional system model, which suggests that plastic debris forms are rock synthetic equivalents in which humans act as depositional and post-depositional agents.