新疆农田土壤中微塑料分离方法优化及其来源、分布和污染特征研究

Microplastics pollution has become a global environmental problem, related research reports were mainly focused on aquatic ecosystems. However, there were few reports on the pollution of microplastics in terrestrial ecosystems, especially in the environmental soil. This project is aimed at the pollution status of microplastics in farmland soils in arid regions of xinjiang, we present the key scientific issues of microplastics source and distribution patterns and size and abundance change laws of different space-time distribution in different types of farmland soil. The research project includes: the separation and extraction method of microplastics is further optimized, combining with previous field investigation and literature review, the surface microstructures are characterized by scanning electron microscopy (SEM), and the microplastics components are identified by attenuated total reflection infrared spectroscopy (ATR-FTIR)and Microscopic Raman spectroscopy (Micro-Raman); The source and distribution of microplastics in soil are analyzed through the study of different crop types of farmland at different depths in the outskirts of Urumqi; The abundance and size variation of microplastics with different crop types farmland soils in different years were further researched and the pollution characteristics such as the category, shape and color of microplastics in soil were also further discussed. This research can provide some scientific basis for risk control and treatment of soil microplastic pollution in arid areas of xinjiang.

微塑料污染已成为全球性环境问题，相关研究报道主要集中在水生生态系统中，但是针对陆地生态系统尤其是土壤中微塑料的污染却鲜有报道。本项目针对新疆干旱区农田土壤中微塑料的污染现状，提出了在新疆干旱区不同类型农田土壤中，不同时空分布的MP 来源、分布规律和MP 大小、丰度变化规律如何的关键科学问题。主要研究内容包括：结合先前的实地调研和文献查阅，进一步优化农田土壤中MP的分离提取方法，并利用扫描电子显微镜表征其表面微形貌，利用衰减全反射红外光谱和显微拉曼光谱鉴定MP的成分类别；通过研究乌鲁木齐市郊不同作物类型农田不同深度耕作层土样，对比分析农田土壤中MP的来源途径和分布规律；深入研究使用不同年份不同作物类型农田土壤中微塑料的丰度、大小变化规律，并进一步探讨土壤中MP的类别，形状，颜色等污染特征。本项目研究可为新疆干旱区农田土壤微塑料污染的风险管控与治理提供一定的科学依据。

微塑料污染已成为全球性环境问题，相关研究报道主要集中在水生生态系统中，但是针对陆地生态系统尤其是土壤中微塑料的污染却鲜有报道。本项目针对新疆干旱区农田土壤中微塑料的污染现状，提出了在新疆干旱区不同类型农田土壤中，不同时空分布的MP&nbsp;来源、分布规律和MP&nbsp;大小、丰度变化规律如何的关键科学问题。主要研究内容包括：结合先前的实地调研和文献查阅，进一步优化农田土壤中MP的分离提取方法，并利用扫描电子显微镜表征其表面微形貌，利用衰减全反射红外光谱和显微拉曼光谱鉴定MP的成分类别；通过研究乌鲁木齐市郊不同作物类型农田不同深度耕作层土样，对比分析农田土壤中MP的来源途径和分布规律；深入研究使用不同年份不同作物类型农田土壤中微塑料的丰度、大小变化规律，并进一步探讨土壤中MP的类别，形状，颜色等污染特征。本项目研究可为新疆干旱区农田土壤微塑料污染的风险管控与治理提供一定的科学依据。取得的主要研究结果如下（1） 建立了普遍适用于干旱区农田土壤中微塑料的分离提取方法和微塑料识别表征方法；（2）发现新疆农田土壤中微塑料的主要来源是残留地膜碎片，且尺寸以< 500μm的薄膜为主；（3）农田土壤中微塑料广泛分布在整个耕作层中；（4）地膜微塑料丰度和老化程度随覆膜年份的增加而增加，尺寸则随年限的增加而逐渐减小；（5）不同农田利用类型中微塑料丰度依次为大棚>菜地>大田；（6）农业活动、作物类型、耕种模式对土壤微塑料污染水平影响显著。项目研究成果可为干旱区农田土壤地膜微塑料对土壤环境效应的影响机制实验设计和地膜源微塑料的污染风险管控与治理提供一定的科学依据。