Comparison of Microplastic Characteristics in Mulched and Greenhouse Soils of a Major Agriculture Area, Korea.

Soil microplastic (MP) contamination through plastic mulch and greenhouse soils is a global concern. However, whether plastic mulch contaminates the soil to a greater or lesser extent than the contamination caused by building greenhouses with MPs has not been documented. This study is the first to examine and compare the abundance and distribution of MPs in greenhouses and mulched soils of Korean agriculture field to obtain the polymer types and sizes of MPs present. The MP abundances in the greenhouse and mulched soils ranged from 50 to 379 and 158 to 943 particles kg^{− 1}, respectively, with an average abundance of 221.4 and 356.8 particles kg^{− 1}. No significant differences (p > 0.05) were observed in soil MP contamination between the greenhouse and mulching sites. At both sites, fragments (91%) were the predominant MP shape. MPs with a size < 300 μm were dominant, covering 99.57% of the mulch site and 99.69% of the greenhouse. Six MP polymers in the greenhouse and mulching sites: polypropylene, polyethylene, polyethylene terephthalate, polyvinyl chloride, polyethylene amide, and polymethyl methacrylate were identified. The soil MP contaminants in greenhouses and mulch sites in the Haean Basin have originated from the use of plastic films, and ropes. The first-hand data established by this study showed the same degree of MP contamination in mulch and greenhouse soils, which provides important background information on MP characteristics to understand the environmental behavior and ecological effects of MPs in soil systematically and comprehensively. [ABSTRACT FROM AUTHOR]