北疆典型棉区土壤微塑料污染现状及分布特征

为研究北疆棉区土壤微塑料的污染现状及分布特征，于2021年4月采集分析了不同覆膜年限(0、5、10、20、30 a)及不同土层深度(0～10、10～20、20～30 cm)的土壤样品。结果表明：北疆棉区土壤中微塑料丰度范围为1 565～3 560个·kg^-1，且随着覆膜年限的增加微塑料丰度值呈现升高趋势，但地膜的使用量与微塑料丰度的关联度逐渐降低，10～30 cm土壤微塑料丰度与地膜的使用量关联度高;该区域土壤微塑料形状主要有薄膜状、碎片状、纤维状和发泡状4种；微塑料颜色包括白色透明、黑色、黄色和其他颜色，所占比例分别为69.02%、14.78%、6.49%和9.71%；微塑料粒径随覆膜年限增加而减小，粒径<0.5 mm的微塑料所占百分比最大;利用傅里叶衰减全反射红外光谱(FTIR)随机调查发现，研究区内土壤微塑料的主要成分分别是聚乙烯(PE)占比45%、聚丙烯(PP)占比20%、聚酰胺(PA)占比16%；各覆膜年限土壤微塑料污染负荷指数在1.70～2.57之间，且随着覆膜年限的增加而增加，研究区微塑料污染负荷指数达到2.09，微塑料污染等级已达重度。研究表...

Soil microplastic pollution and distribution characteristics in a typical cotton field in northern Xinjiang, China

In order to study the soil microplastic pollution and distribution characteristics in typical areas of cotton cultivation in northern Xinjiang, in April 2021, we collected soil samples from different depths(0-10, 10-20 cm, and 20-30 cm) from a field that had been subjected to film mulching for different lengths of time(0, 5, 10, 20 years, and 30 years). Analysis of the samples revealed that the abundance of microplastics in the soil of the cotton field ranged from 1 565 items·kg^-1 to 3 560 items·kg^-1, and showed an increasing trend with a longer period of time under film mulching.The degree of correlation between the amount of agricultural film mulch and the abundance of microplastics gradually decreased, whereas the degree of correlation between the abundance of microplastics and the amount of agricultural film mulch in the 10-30 cm soil layer was high. There were four types of soil microplastic, namely film, debris, fibers, and foam. The microplastics differed in color, with transparent white, black, and yellow being the most common, accounting for 69.02%, 14.78%, and 6.49% of the total microplastics, respectively. Other colors contributed to the remaining 9.71%. The size of microplastic particles decreased with an increase in coating life, with the largest fraction being those microplastics with particle size of <0.5 mm. Analysis of random samples using Fourier attenuated total reflection infrared spectroscopy revealed that the main components of soil microplastics in the study area were polyethylene(45%), polypropylene(20%), and polyamide(16%). The soil microplastic pollution index for soils subjected to film mulching for a different number of years ranged from 1.70 to 2.57, which increased with an increase in the length of time under film mulching. The microplastic pollution load index in the study area reached 2.09, indicating that the microplastic pollution had reached a severe level. The findings of this study reveal different extents of microplastic pollution in the study area, and accordingly the ecological risks posed by microplastic pollution should be assessed.