摘要
为研究黔西北炼锌矿区土壤和矿渣中重金属总量及形态分布特征,采用Tessier五步连续提取法和风险评价编码法(RAC)探讨其污染程度。结果表明,除Cr和Ni外,其他各重金属平均值均超出贵州省的土壤背景值,其中Pb、Zn、Cd污染严重。形态分析表明,土壤和矿渣样品中Pb、Zn、Mn以残渣态(分别占其总量的45.91%、55.11%、42.71%)和铁锰结合态(分别占其总量的33.33%、28.26%、41.78%)为主;Cd的可交换态和碳酸盐结合态之和占总量的30.63%;Cu的有机结合态为65.11%,其次是残渣态30.79%;Cr和As则以残渣态为主要形态,平均占比均超过90%。RAC评价结果表明,矿区周边土壤中Cd元素具有极高的潜在生态风险,其他重金属潜在生态风险水平较低。
Contents and spatial distribution of heavy metals in the soils of the zinc mining area in northwestern Guizhou Province were investigated and characterized and pollution degrees and risks of the heavy metals were analyzed and assessed with the Tessier sequential extraction method and risk assessment code ( RAC), respectively. Results show that the average contents of all the studied heavy metals, except Cr and Ni, were higher than their respective background values of Guizhou Province. The soils were seriously contaminated with Pb, Zn and Cd in samples. Fractionation of the pollutants shows that in the soils and slag, Pb, Zn and Mn existed mainly in the form of residue ( accounting for 45.91%, 55.11% and 42. 71% of their respective total), and in ferromanganese bound form (33.33%, 28.26% and 41.78%) , Cd in exchangeable form and carbonate bound form, together making up 30. 63%; Cu in organo-bound form (65.11%) and then in the form of residue (30.79%) ; and Cr and As in the form of residue (both exceeding 90%). RAC shows that Cd in the soil poses a very high potential ecological risk, while the others have relatively low ones.
作者
冯艳红
郑丽萍
应蓉蓉
张亚
林玉锁
王国庆
FENG Yan-hong Zheng Li-ping YING Rong-rong ZHANG Ya LIN Yu-suo WANG Guo-qing(Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing 210042, China)
出处
《生态与农村环境学报》
CAS
CSCD
北大核心
2017年第2期142-149,共8页
Journal of Ecology and Rural Environment
基金
环保公益性行业科研专项(201409041
201409042)
2015年中央级公益性科研院所基本科研业务专项
中国工程院全国土壤环境保护及污染防治战略咨询研究项目
江苏省自然科学基金(BK20130104)
国家自然科学基金(41301278)
关键词
炼锌矿区
镉(CD)
重金属形态
风险评价
zinc mining area
cadmium
speciation of heavy metal
risk assessment