Effect of LDPE microplastics on chemical properties and microbial communities in soil. (20th April 2022)

• Record Type: Journal Article
• Authors: Palansooriya, Kumuduni Niroshika; Shi, Liang; Sarkar, Binoy; Parikh, Sanjai J.; Sang, Mee Kyung; Lee, Sang‐Ryong; Ok, Yong Sik
• Is Part Of: Soil use and management. Volume 38:Number 3(2022)
• Page Start: 1481
• Page End: 1492
• Publication Date: 2022-04-20
• Subjects: Actinobacteria -- heavy metals -- low‐density polyethylene -- microbial community -- microplastics -- soil quality; Soil management -- Periodicals; 631.4
• DOI: 10.1111/sum.12808
• Languages: English
• ISSNs: 0266-0032

Abstract

Abstract: The accumulation of plastics in the soil ecosystem poses an increasing environmental concern worldwide. However, little is known about the effect of plastic concentrations on soil properties and soil biota. In this study, we investigated the effect of low‐density polyethylene (LDPE) microplastics (MPs) on the chemical and microbial properties of agricultural soil using a set of microcosm experiments. The soil was incubated for 100 days with LDPE at concentrations of 0%, 0.1%, 1%, 3%, 5%, and 7% at 25°C with 70% water‐holding capacity. Along with soil chemical analysis, we conducted an analysis of soil microbial properties on the first day and again after 100 days of incubation. LDPE concentrations of ≥1% significantly ( p < .05) decreased the pH but increased the electrical conductivity of the soil in comparison with the control (0% LDPE at 100 days). Increasing the LDPE concentration did not affect the soil exchangeable cation content or the available Pb concentration. Firmicutes were the most abundant phyla in the soil on the first day, whereas Proteobacteria, Firmicutes and Actinobacteria became dominant in all treatments after 100 days. An increasing LDPE concentration increased the abundance of Actinobacteria and decreased Proteobacteria. Principal component analysis demonstrated that only 7% LDPE was positively correlated with Actinobacteria, indicating that higher concentrations of LDPE contributed to the growth of this phylum. The findings of this study imply that MP contamination could affect soil chemical properties and microbial activity and that these effects primarily depend on MP concentrations in soil.