College - Author 1
College of Engineering
Department - Author 1
Materials Engineering Department
Degree Name - Author 1
BS in Materials Engineering
Date
6-2023
Primary Advisor
Trevor Harding, College of Engineering, Materials Engineering Department
Additional Advisors
Seeta Sistla, College of Agriculture, Food, and Environmental Sciences, Natural Resources Management and Environmental Sciences Department
Abstract/Summary
Plastic pollution in aquatic systems has traditionally been highlighted in past and current research due to the increase in plastic production every year. Unfortunately, quantitative and qualitative data regarding plastic pollution on land systems such as agricultural mulch is limited. Agricultural mulch breaks down into macroplastics and then degrades into microplastics. The microplastics investigated in this study are all secondary microplastics: microplastics that form due to weathering of larger fragments of plastic. Weathering can occur due to a variety of factors; however, UV radiation and mechanical weathering have been the factors of focus on most current research in microplastic formulation. Microplastic characterization has commonly been done using Fourier-Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) instrumentation. FTIR analysis of the microplastic samples can be used to quantify the amount of photooxidation that occurred in association with UV radiation. SEM analysis of the microplastic samples provides insight on the surface characteristics, size, and shape of the microplastic samples. This study investigated the surface characterization of fresh and field deployed low-density polyethylene mulch to address the gap in knowledge regarding the effect of plastic pollution on agricultural soils and better understand microplastic formation on agricultural land systems. Shredding was identified as the dominant damage feature present in the LDPE mulch samples. The thickness of the mulch affected the total amount of damage and surface area loss due to weathering conditions.
URL: https://digitalcommons.calpoly.edu/matesp/274