西宁火烧沟下游表层泥质沉积物中重金属含量及评价  

Concentration and Assessment of Heavy Metals in Surface Sediment in the Lower Reaches of Huoshaogou,Xi′ning City

作　　者：常华进[1,2] 曹广超[2] 陈克龙[1,2] 

机构地区：[1]青海师范大学生命与地理科学学院,西宁810008 [2]青藏高原环境与资源教育部重点实验室,西宁810008

出　　处：《水土保持研究》2013年第5期247-250,256,共5页Research of Soil and Water Conservation

基　　金：青海师范大学科研创新计划项目;国家自然科学基金(41002011)

摘　　要：重金属元素是一类重要的污染物,研究其在表生环境中的含量及污染程度,对于环境保护和治理具有重要意义。利用ICP-MS测试方法对青海省西宁市火烧沟下游城区段表层泥质沉积物中As,Cd,Pb,Ti,V,Cr,Mn,Ni,Cu,Zn共10种重金属元素的含量进行了分析测定,并利用污染系数、地累积指数和潜在生态危害指数等指标评估了其污染程度。结果表明:火烧沟下游表层泥质沉积物中Cd,Cr和Zn含量(平均值分别为0.39μg/g,183μg/g和135μg/g)明显高于青海省土壤平均值,As和Pb含量(平均值分别为16.0μg/g和21.9μg/g)接近或略高于青海省土壤平均值;Cd污染明显,达到了中等—较高生态危害风险级别,其他元素为低生态危害风险级别;多风险因子指数(119.4)显示已达到中等生态风险级别。火烧沟下游已出现较明显的重金属污染,应控制As,Pb,Cr,Zn,尤其是Cd向火烧沟中的排放。Heavy metals are the important pollutants in surface environment, and it has great significance to study their concentrations and contamination levels in terms of environmental protection and control. Con- centrations of heavy metals including As, Cd, Pb, Ti, V, Cr, Mn, Ni, Cu and Zn in surface sediment in the lower reaches of Huoshaogou in Xi＇ning City have been analyzed using ICP-MS, and contamination evaluation has been carried out using multiple parameters including the pollution coefficient, the geoaecumulation index and the potential ecological risk. Results show that concentrations of Cd, Cr and Zn in the sediments are av- erage 0.39μg/g, 183 μg/g and 135 μg/g, respectively, which are significant higher than the soil average lev- els of Qinghai Province, and concentrations of As and Pb are average 16.0 μg/g and 21.9 μg/g, respectively, which are near or somewhat higher than the soil average levels of Qinghai Province. The potential ecological risk evaluation indicates that Cd is the most important pollutant and belongs to middle-high ecological risk, and the other elements belong to low ecological risk. The ecological risk index of the ten heavy metals rea- ches up to 119.4 and belongs to middle ecological risk, which indicates that Huoshaogou lower reaches is suf- fering from obvious contamination. The results suggest that significant heavy metal pollution exists in the surface sediment in the Huoshaogou lower reaches, and sewage discharge with As, Pb, Cr, Zn, especially Cd into the river should be restricted.

关 键 词：重金属 泥质沉积物 火烧沟 西宁市 

分 类 号：X820.4[环境科学与工程—环境工程]