摘要
以北京市平谷区金矿区周边土壤为研究对象,采集40个表层(0~20 cm)土壤样品,测定土壤中As、Hg总量及其各赋存形态含量,并采用基于重金属形态的次生相原生相分布比值法(ratio of secondary phase to primary phase, RSP)和风险评价编码法(risk assessment code, RAC)对土壤中As、Hg污染程度及生态风险进行评价。结果表明:各采样区土壤中As、Hg总量均超出北京市土壤背景值,分别超出3.94~13.24,11~41.33倍;土壤中As、Hg主要以残渣态存在,除残渣态外,As主要以铁锰氧化态存在,开采沟和尾矿库土壤中Hg主要以碳酸盐结合态存在,开采沟下游和尾矿库外土壤中Hg则主要以强有机态存在;污染程度和生态风险评价结果显示,开采沟及下游土壤As、Hg污染程度较低,研究区土壤中As、Hg整体表现较低风险,在开采沟、YZ尾矿库和JHH尾矿库存在Hg的高风险和极高风险点位,应予以重视。研究结果为治理金矿区周边土壤As、Hg污染提供参考。
Concentrations and speciation characteristics of arsenic and mercury in 40 surface soil samples around a gold mining area in Pinggu District of Beijing were determined. The pollution and ecological risk of arsenic and mercury were evaluated by the Ratio of Secondary Phase to Primary Phase(RSP) and Risk Assessment Code(RAC). The results showed that the average concentrations of arsenic and mercury in the soil exceeded the background values of soil, by 3.94~13.24 times and 11~41.33 times respectively;arsenic and mercury were primarily dominated by residual fraction, in addition to the residual fractions, arsenic in the soil of mining gully and tailings pond was bound to the Fe-Mn oxides, whereas mercury in the soil downstream of mining gully and outside the tailings pond was bound to the carbonate and the organics;the results of the pollution and ecological risk showed that the pollution degree of arsenic and mercury in the soil of mining gully and downstream was relatively lower, in the soil of the study area arsenic and mercury were at lower risk;in the soil of mining gully, YZ tailings pond and JHH tailings pond mercury were at high and extremely high risk, respectively, which should be paid attention to. The results provided a reference for treating arsenic and mercury pollution in the soil around the gold mining area.
作者
周颖
王雪梅
蒋玉琢
赵云峰
季宏兵
ZHOU Ying;WANG Xue-mei;JIANG Yu-zhuo;ZHAO Yun-feng;JI Hong-bing(School of Energy and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China;Geological Engineering Design and Research Institute,Beijing 101500,China;College of Resource Environment and Tourism,Capital Normal University,Beijing 100048,China)
出处
《环境工程》
CAS
CSCD
北大核心
2021年第8期203-210,164,共9页
Environmental Engineering
基金
国家自然科学基金项目(41173113,41473122)。
关键词
重金属
金矿
尾矿库
赋存形态
生态风险
heavy metal
gold mine
mine tailings
speciation
ecological risk
