阳宗海不同深度沉积物中微塑料的赋存特征及来源分析

Occurrence Characteristics and Sources of Microplastics in Sediments at Different Depths in Yangzong Lake

为探究阳宗海不同深度沉积物中微塑料的污染特征及来源,于2022年6月布设8个采样点并利用重力取样器采集30 cm的沉积物短钻,采用密度浮选法分离沉积物中的微塑料,利用体视显微镜和拉曼光谱仪器对微塑料的理化特征进行检验.结果表明:阳宗海0~10 cm、10~20 cm、20~30 cm深度沉积物中微塑料平均丰度分别为(782.11±313.97)个/kg、(188.68±52.95)个/kg和(148.32±68.34)个/kg,整体平均丰度为(373.04±345.39)个/kg,丰度随深度递减.微塑料形状以纤维状为主,颜色以蓝色和透明为主,粒径主要集中在2 mm以下;主要聚合物类型为聚乙烯(PE)和聚氯乙烯(PVC).结合微塑料理化特征和周边人类活动,渔网和纺织品可能是微塑料的主要来源.

To investigate the pollution characteristics and sources of microplastics in sediments of different depths in Yangzong Lake,in June 2022 short drills of 30 cm of sediment were collected from 8 sampling points in Yangzong Lake using a gravity sampler,and microplastics in the sediments were separated by density flotation,and the physical and chemical characteristics of the microplastics were examined by using stereomicroscope and Raman spectrometer.The results showed that the average abundance of microplastics in 0~10 cm,10~20 cm and 20~30 cm sediments in Yangzong Lake was(782.11±313.97),(188.68±52.95)n/kg and(148.32±68.34)n/kg.The overall average abundance was(373.04±345.39)n/kg,and the abundance decreases with depth.The shape of microplastics is mainly fibrous,and the color is blue and transparent.Furthermore,the particle size is mainly concentrated below 2 mm.The main polymer components were polyethylene(PE)and polyvinyl chloride(PVC).Fishing nets and textiles are probably the main sources of microplastics by combining with the characteristics of microplastics and surrounding human activities.