Patterns of accumulation of plastics and other trash on beaches on the Baja California peninsula

Keywords: marine plastic pollution, plastic on beaches, Baja California
Abstract Type: Poster Abstract

Abstract

Since the beginning of their mass manufacture over a half-century ago, plastics have become a ubiquitous environmental pollutant. Massive amounts of plastic trash are deposited on remote islands, and these have garnered much attention in recent years. Marine plastic pollution threatens biodiversity, but understanding the extent of environmental contamination and the hazards to biodiversity are complicated by a dearth of data on accumulation patterns and rates. I document the amount of several types of anthropogenic debris accumulated on eleven beaches on the Baja California Peninsula surveyed four times between 2017 and 2022. Beaches were sampled at the high tide line, the mid beach, and along the dune line. Sampling was in 10 square meter quads for each zone. I report on the total amount of debris by type, identify differences in debris density according to beach zone, and calculate the mass and volume of the trash in each sample quad to extrapolate total mass and volume of trash on each beach. I also compare the results of two sampling strategies used by previous researchers. Though only one component of the debris accumulating in marine and coastal environments, plastics make up the dominant contribution of marine trash pollution. While microplastics dominate in more distal locations where buoyant and durable plastic waste might degrade over a journey of several years or more, much younger macroplastic debris is more common in continental coastal environments, as near shore currents tend to trap much debris in coastal waters and keep it there.