DEGRADATION OF LOW-DENSITY POLYETHYLENE AND PLANTANUS ACERIFOLIA LEAVES IN AN EPHEMERAL POND AND ARID GRASSLAND

Amy K Fetters; California State University, Bakersfield; afetters@mcbioinc.com; Rae E McNeish

Plastic pollution is a pervasive contaminant of concern worldwide. To understand the fate of plastic pollution in arid landscapes, I am investigating how low-density polyethylene plastic degrades compared to naturally occurring leaves from Plantanus acerifolia (London planetree) in terrestrial and freshwater habitats. I investigated 1) if leaf and plastic degradation rates differ, and if this pattern is consistent across habitats, and 2) how leaf and plastic materials impact macroinvertebrate communities. A traditional leaf pack experiment was conducted with three treatments; natural leaves, plastics, and a mix of both materials. Leaf packs were anchored in a grassland and ephemeral pond in February 2021 (n = 55 treatment habitat-1) and subsets were harvested every 1-3 months for one year (n = 3-6 leaf packs treatment-1 habitat-1). Results indicated that plastic degraded 115 × faster in the grassland compared to the pond, while natural leaves degraded 1.7 × faster in the pond compared to the grassland. Macroinvertebrates did not preferentially colonize certain leaf pack treatments, suggesting that plastic could serve as an alternative habitat resource for macroinvertebrates. This study provides insight into how varying environmental conditions can impact plastic degradation in the environment, advancing knowledge on the fate of plastics in arid habitats.

Poster Session  InPerson Presentation