[Temporal and Spatial Distribution of Microplastic Contamination in Soil and Influencing Factors: A Global Analysis]

Soil microplastic contamination is an increasingly serious global environmental challenge with significant implications for soil health, ecosystem functioning, and potential human health risks. This study provides a comprehensive analysis of the spatial and temporal distribution patterns of soil microplastic pollution across different geographic regions. Data were synthesized from 94 published studies, encompassing 1 629 sampling sites collected between 2008 and 2022. The analysis revealed marked regional differences in microplastic abundance. Soils in China exhibited the highest pollution levels (mean: 3 486.0 items·kg^-1), followed by EU countries (mean: 2 334.7 items·kg^-1), while North America showed relatively lower concentrations (mean: 443.5 items·kg^-1). Temporal trends indicated a significant increase in soil microplastic contamination since 2015, coinciding with the rapid global growth in plastic production, which surpassed 350 million tons annually. Land use assessments showed that forest and unused lands contained significantly higher concentrations of microplastics compared to agricultural and urban soils. This suggests complex pollution pathways that extend beyond direct human activities. Correlation analysis and XGBoost modeling identified agricultural and industrial activities as the primary drivers of soil microplastic accumulation, surpassing factors such as population density or general economic indicators in explanatory power. The study further underscores the critical importance of standardized detection methods, as analytical techniques significantly influence the reported levels of contamination. These findings offer essential insights for the development of targeted mitigation strategies and policy frameworks to address the escalating issue of soil microplastic pollution, highlighting the need for an integrated approach that simultaneously addresses economic development and environmental protection goals.