Evaluating the impacts of Microplastics on Soil and Plant Health: A Greenhouse Pot Experiment

Voiceover

Presenter(s)

Cortiney Galuska, Vincent McKnight

Abstract or Description

Microplastics (MPs) have been studied extensively in terms of their impacts on marine life, but there is a much smaller body of research targeting the impact of MPs pollution on terrestrial ecosystems. This is particularly important given that many terrestrial plants form the basis of our economy and our diet. Furthermore, the presence of high concentrations of MPs can alter soil physical and chemical properties, which in turn may have negative effects on soil biological communities and their functions and plant growth and performance. Therefore, we will conduct a greenhouse pot experiment for 70 days to evaluate how different volumes and MP size fractions of Polyethylene Terephthalate (PET) will impact growth of tomato plants (Solanum lycopersicum) and the biological, chemical, and physical properties of soils. In addition to a control treatment, we will have nine MP treatments (three size fractions × three volumes × five replications), comparing MP volumes (relative to soil, W/W) of 0.1%, 1%, and 5% and size fractions of 0.5 mm, 1 mm, and 2 mm for each volume treatment. Tomato plants will initially be grown in single seed cells for an incubation time of 14 days. After incubation, the healthy tomato plants will be transferred to the one-gallon pots. Plant growth measurements (shoot length, flower/fruiting number) will be taken weekly, and the plants will be harvested at the end the study to measure root/shoot volume. Soil composition parameters will be measured pre and post treatment to test for significant differences in several physical (e.g., soil moisture content and soil compaction), chemical (e.g., pH, electrical conductivity, soil organic matter, macro- and micro-nutrients), and biological (e.g., microbial biomass, enzymes, and mineralizable nitrogen) soil health indicators. The knowledge from this study will increase our understanding of soil and plant health due to MP contamination on terrestrial ecosystems.

Mentor

Dr. Ruhland and Dr. De