Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China.
Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China.
Chemosphere. 2023 Nov;342:140146. doi: 10.1016/j.chemosphere.2023.140146. Epub 2023 Sep 11.
As the third largest river in the world, microplastic pollution in the Yangtze River basin is currently attracting worldwide attention. However, fragmented research information is insufficient to reveal the occurrence and driving mechanisms of microplastics throughout the Yangtze River basin. Building on a systematic review of 20 existing publications, this study constructed a dataset including microplastic data from 366 samples in the Yangtze River basin through a data filtering process, and data on natural conditions and anthropogenic activities from 101 basin municipalities. Further, multivariate statistical analysis was utilized to enhance the understanding of the abundance, composition and drivers of microplastics within the basin. Differences in microplastic abundance among the sampling sites were up to 5 orders of magnitude, with the highest abundance value found in the upstream city of Chengdu. The comprehensive diversity index used to describe the composition characteristics of microplastics ranged from 0.31 to 0.68, slightly higher than the national average. Based on a statistical analysis framework, natural conditions and anthropogenic activities were shown to jointly drive the distribution of microplastics, and the dominant driver shifted between the two with spatial variation. In the upstream, anthropogenic activities dominated by GDP (r = 0.85, P < 0.01) were the main positive factor. In the middle and downstream, natural conditions and anthropogenic activities had comparable driving forces as the stability of natural resistance increased, and both were positively correlated with microplastics. Combining the constructed normalized stepwise linear regression model with GIS spatial analysis, the basin-wide application demonstrated that microplastic pollution in the upstream and delta deserved more attention. After coupling the distance factors, microplastic pollution was concentrated in the middle and downstream of the Yangtze River basin, covering important drinking water sources. This study provided important data support for subsequent targeted microplastic reduction and treatment.
作为世界第三大河，长江流域的微塑料污染目前引起了全球关注。然而，碎片化的研究信息不足以揭示整个长江流域微塑料的发生和驱动机制。本研究在对 20 篇现有文献进行系统综述的基础上，通过数据过滤过程，构建了一个数据集，其中包括来自长江流域 366 个样本的微塑料数据，以及来自流域 101 个城市的自然条件和人为活动数据。此外，还利用多元统计分析方法增强了对流域内微塑料丰度、组成和驱动因素的理解。采样点之间的微塑料丰度差异高达 5 个数量级，丰度最高的采样点位于上游城市成都。用于描述微塑料组成特征的综合多样性指数范围在 0.31 到 0.68 之间，略高于全国平均水平。基于统计分析框架，自然条件和人为活动共同驱动了微塑料的分布，且随着空间变化，主导驱动因素在两者之间发生转换。在上游地区，以 GDP 为主导的人为活动（r = 0.85，P < 0.01）是主要的积极因素。在中下游地区，随着自然阻力的稳定性增加，自然条件和人为活动的驱动力相当，两者均与微塑料呈正相关。将构建的归一化逐步线性回归模型与 GIS 空间分析相结合，进行全流域应用表明，上游和三角洲地区的微塑料污染更值得关注。在耦合距离因素后，微塑料污染集中在长江中下游地区，覆盖了重要的饮用水源。本研究为后续有针对性的减少和处理微塑料提供了重要的数据支持。
