Characteristics and driving factors of microplastics in surface water environment of China
In order to elucidate the occurrence characteristics and driving factors of microplastics in the surface water environment of China,this study based on published literature collected microplastic characteristics,experimental methods,and geographical environmental information from 1944 sampling sites.The research showed that the abundance of microplastics in the surface water environment of China ranged from 0 to 204183items/m3,and in sediment from 0to 79931items/kg.The abundance of microplastics exhibited significant spatial heterogeneity in the surface water environment of China.In water bodies,the abundance of microplastics was highest in inland river basins(13185.77items/m3),and the lowest was found in the Southeast rivers basin(2678.07items/m3).In sediment,the Huai River basin had the highest level of microplastic abundance(2145.61items/kg),while the Hai River basin had the lowest abundance(294.82items/kg).The morphologies of microplastics in water and sediment were mainly fibrous(58.29%/47.21%)and fragments(23.20%/30.03%),respectively.Small microplastics(<0.5mm)constituted the majority based on particle size(59.61%/62.76%).Transparent microplastics accounted for the largest proportion in terms of color(30.18%and 28.17%,respectively).The main materials of microplastics were polyethylene(PE)(25.49%/27.78%)and polypropylene(PP)(25.36%/22.69%).The characteristics of microplastics in water bodies are primarily influenced by natural environmental factors,with abundance,shape,and color features all significantly correlated with environmental factors such as temperature and precipitation.In contrast,the characteristics of microplastics in sediments are mainly influenced by socio-economic factors,with abundance,shape,and particle size features significantly correlated with socio-economic environmental factors such as GDP,night light intensity,and population density.Significant differences in microplastic characteristics,including abundance,morphology,color,and polymer types,are observed under different experimental treatments.Path analysis using partial least squares indicates that the influence of experimental treatments on microplastic characteristics is comparable to the geographical environment.The lack of standardized experimental methods makes it difficult to compare and validate different experimental results,highlighting the urgent need for the establishment of standardized experimental procedures to minimize the impact of experimental treatments on the observation of microplastic characteristics.
surface water environmentmicroplastic characterizationfugacity characterizationdriversgeographyexperimental procedure