淮河上游沉积物中重金属分布特征及污染评价

Distribution and Pollution Assessment of Heavy Metals in Sediments from Upper Reaches of Huaihe River

为了解淮河上游沉积物中重金属的含量及潜在生态危害程度,用电感耦合等离子质谱法和电感耦合等离子发射光谱法测定了16个采样点沉积物中Cu、Cr、Zn、Cd、Pb等5种重金属元素的含量,对沉积物中重金属元素的污染状况和潜在生态危害进行了评价。与河南省土壤重金属元素地球化学背景值相比,Cd富集最严重,其次为Pb;相关分析及主成分分析表明,淮河上游沉积物中Zn、Cu和Cr主要来源于岩石的自然风化与侵蚀过程,Cd主要来源于工业排污、化石燃料的燃烧以及农业活动,上述两种来源对Pb均有影响;地积累指数及潜在生态危害评价结果表明,部分采样点Cd的污染程度达到中等和强生态危害水平,应予以重视。

In order to understand the contamination level and ecological risk of heavy metals in surface sediments from the upper reaches of Huaihe River,Cu,Cr,Zn,Cd and Pb in 16 sediment samples were measured by inductively coupled plasma mass spectrometry( ICP-MS)and inductively coupled plasma optical emission spectrometer( ICP-OES). Compared with the background value of soil from Henan Province,Cd was enriched to some extent and followed by Pb. The potential source of heavy metals in sediments from the upper reaches of Huaihe River was identified by correlation analysis and principal component analysis. The results show that Zn,Cu and Cr mainly originate from natural weathering and erosion process; Cd mainly originates from human activities including industry,traffic and usage of fertilizer;both processes have influence on the content of Pb. The geo-accumulation index( Igeo) and the Hakanson potential ecological risk index indicate that Cd pollution is the most serious among all heavy metals in sediments from the upper reaches of Huaihe River.