Seasonality, wind and characteristics of plastic polymer accumulation on Western Australia's south coast

Abstract

Global studies have investigated plastic polymer distribution, but few have investigated the drivers of polymer deposition. Little work has been done in Australia, particularly on Western Australian beaches. In 2018, Wow Ecotours collected daily plastic samples from Shelley Beach on the south coast of Western Australia. A subset of 873 items was taken from five different density categories, and their polymer types were identified using Raman Spectrometry. The most abundant polymer was high-density polyethylene 45 %, followed by polypropylene and low-density polyethylene, with 33.5 % and 14 %, respectively. Onshore wind was the predominant factor driving plastic accumulation on the beach, but this did not vary significantly between polymers. The spring season has significant fluctuations in the length, mass, and area of the collected samples.