[Occurrence Characteristics and Ecological Risk Assessment of Microplastics in Different Land Use Types in China]

Microplastics， as an emerging pollutant， pose significant potential risks to environmental media due to their persistent nature. In this study， 6，008 soil samples were selected from 71 articles published between 2018 and 2024. Data on microplastic abundance， morphological features， and polymer types were collected to investigate the characteristics of microplastic pollution across different land use types in China， the correlations between their properties， and the variations in ecological risks. The results revealed that the order of microplastic abundance was agricultural soils （average abundance： 3 856.834×10³ items·kg^-1） > unused lands （1 002.34×10³ items·kg^-1） > construction lands （461.21×10³ items·kg^-1）. The most prevalent microplastic shapes in Chinese soils were fragments， fibers， and films， with sizes predominantly concentrated in small particles （0-0.5 mm）. Transparent， black， and white were the most frequent colors observed， while polypropylene （PP） and polyethylene （PE） emerged as the dominant polymer types. Moderate correlations were found between microplastic abundance and color/shape in agricultural soils， whereas strong correlations existed between abundance and polymer types in construction land soils. Soil microplastic pollution in China arises from the combined effects of multiple factors， including economic development， the tertiary sector， agricultural practices， and human activities. Studies have shown that agricultural lands exhibit the highest ecological risk， while unused lands present relatively lower risks.