Although environmental research has recently begun to focus on the ubiquity of microplastics in terrestrial systems, there is still lack of comprehensive data which describe microplastics levels in soils and the factors influencing the distribution of this contaminant. Here, we show that microplastics contamination (3877 ± 2356 p·kg^‒1) is omnipresent in numerous soil samples collected along the Yangtze River. Subsoils (4005 ± 2472 p·kg^‒1) showed higher levels of microplastics than topsoils (3748 ± 2301 p·kg^‒1), while polyamide (32%) was the most commonly found polymer in the samples. Small microplastics particles (<200 µm) accounted for approximately 70% of the microplastics detected in subsoils. In terms of shape, microfragments were the most common type of microplastic particle, accounting for 34% of total microplastics, followed by microfibers (30%). Furthermore, microplastics contamination was found to be positively correlated with both the population of the study area and precipitation, yet negatively correlated with the elevation of the sampling site. Our study represents the first large-scale study of microplastic contamination in riparian soils along the Yangtze River, and provides important data regarding the ecotoxicology and ecosystem effects of microplastics in terrestrial environments.

尽管最近的环境研究开始着眼于地面系统中普遍存在的微塑料，但仍然缺乏描述土壤中微塑料含量以及影响该污染物分布的因素的综合数据。在这里，我们发现沿长江采集的大量土壤样品中普遍存在微量的塑料污染（3877±2356 p·kg ^‒1）。底土（4005±2472 P·千克^-1）显示出更高水平的塑料微粒的比表层土（3748±2301 P·千克^-1），而聚酰胺（32％）是样品中最常见的聚合物。微小的塑料微粒（<200 µm）约占地下土壤中检测到的塑料微粒的70％。就形状而言，微碎片是最常见的微塑料颗粒类型，占微塑料总量的34％，其次是微纤维（30％）。此外，发现微塑料污染与研究区域的人口和降水均呈正相关，而与采样地点的高度呈负相关。我们的研究代表了长江沿岸土壤中微塑性污染的首次大规模研究，并提供了有关陆地环境中微塑性的生态毒理学和生态系统影响的重要数据。