“河-湖”沉积物重金属环境特征及来源解析

以府河及其受纳湖泊为研究对象,辨识"河-湖"系统沉积物中重金属的空间分布、地球化学特征和生态风险,利用正定矩阵因子分解模型(PMF)解析沉积物中重金属的潜在来源.结果表明,该"河-湖"系统沉积物中主要金属污染物为Cd、Cu和Zn,且Cd存在生态风险.与受纳湖体相比,府河污染水平及风险程度更高.湖体空间分析显示,河流入口呈现更高的金属含量及风险水平.PMF分析表明,研究区沉积物重金属主要受到人为活动的影响(55.7%),包括工业排放(20.3%)、化肥施用(19.5%)和水产养殖(15.9%).

Environmental Characteristics and Source Apportionment of Heavy Metals in the Sediments of a River-Lake System

In this study, the geochemical characteristics and ecological risks of heavy metals in the sediments of a river-lake system were comprehensively identified and the spatial distribution was analyzed. Meanwhile, the potential sources of heavy metals in the sediments were apportioned using the positive matrix factorization model (PMF). The elements Cd, Cu, and Zn were identified as the main pollutants in the sediments of the river-lake system; in particular, Cd indicated an ecological risk. Compared with receiving lakes, the river is more polluted and poses a more significant risk. Spatial analysis of the lake suggested that the entrance of rivers had a relatively higher pollution degree and risk, indicating that rivers may be an important channel to transfer pollutants into the lake. PMF modelling showed that the heavy metals in the sediments were mainly associated with human activities (55.7%), including industrial emissions (20.3%), fertilizer application (19.5%), and aquaculture (15.9%).