摘要
【目的】分析新疆温宿县林果土壤重金属As、Hg、Cd、Pb和Cr的含量,明确该区域的重金属含量及分布状况,并对其安全性进行风险评价。【方法】2014年对温宿县5.33×104hm2（80万亩）林果取样调查,根据林果分布、树龄及土壤特征在1 300个样点中选取代表性138个样点,测定重金属As、Hg、Cd、Pb和Cr的总含量。采用污染指数法和潜在生态风险指数法,结合新疆土壤背景值、国家土壤质量二级标准,进行该区的土壤重金属总量分析和重金属污染评价。【结果】温宿县土壤重金属,As平均含量11.96 mg/kg,Hg平均含量0.032 mg/kg,Cd平均含量0.17 mg/kg,Pb平均含量22.93 mg/kg,Cr平均含量43.38 mg/kg,且5种土壤重金属变异系数均较小。以国家土壤环境质量标准（二级）为基础,各元素的污染指数污染程度排序为：As〉Cd〉Cr〉Pb〉Hg。污染评价表明,5种重金属元素（As、Hg、Cd、Pb和Cr）在温宿县土壤的单因子污染指数（Pi）中,均属于安全等级（Pi≤1）,为清洁水平;就综合污染指数（Ps）而言,该区域的土壤重金属元素污染程度也均属于安全等级（Px≤0.7）,为清洁水平;单因子潜在生态风险评价指数的平均值表明,温宿县5种重金属的潜在生态危害排序为：Hg（77.35）〉Cd（42.60）〉As（11.03）〉Pb（7.96）〉Cr（1.01）,重金属As、Pb和Cr处于低生态风险程度（Eir〈40）,重金属Hg和Cd处于中生态风险程度（Eir〈80）。5种重金属的综合潜在生态风险指数的范围为79.78~236.10,处于低生态风险程度（RI=139.94〈150）。【结论】新疆温宿县土壤重金属（As、Hg、Cd、Pb和Cr）含量均低于警戒线,污染程度均处于安全等级,单因子、综合生态风险评价也均属于低生态风险程度,说明温宿县的土壤环境质量整体良好。
[ Objective ] To make clear the level of heavy metal contamination by analyzing the total quan- tity in Wensu County and conduct risk assessment of their safety. [Method]In 2004, 138 soil samples in 17 sampling points in Wensu County were collected, and the total content of heavy metals （ As, Hg, Cd, Pb and Cr） was determined. [ Result]The results showed that in Wensu county As was 11.96 mg/kg, Hg 0.032 rag/ kg, Cd 0.17 mg/kg, Pb 22.93 mg/kg, Cr 43.38 mg/kg. The coefficient variability of heavy metals was real- ly little. According to the state soil environmental quality standards as the evaluation standard, the integrated pollution indexes of various elements were ： As 〉 Cd 〉 Cr 〉 Pb 〉 Hg. The pollution assessment showed that five kinds of heavy metals were all at security and clean level（ Pi ≤ 1 ）, so was the comprehensive pollution indices of heavy metals（ Px ~〈0.7）. The average values of potential ecological risk assessment showed that the various elements were： Hg （77.35） 〉 Cd （42.60） 〉 As （11.03） 〉Pb （7.96） 〉Cr（1.01）, a lower ecological risk level was estimated to soil heavy metals. The comprehensive range of potential ecological risk index of five finds of heavy metals was between 79.78 and 236.10, so a lower ecological risk level was determined, too. [ Conclusion] In Wensu county, the heavy metal contamination （As, Hg, Cd, Pb and Cr） is lower than the warning level, and the degree of pollution is below the safe level. The single factor and comprehensive ecologi- cal risk assessment are also at a low ecological risk, which indicates that the soil environmental quality is over- all good in Wensu County.
作者
付彦博
窦晓静
赖宁
黄建
王新勇
王治国
FU Yan- bo DOU Xiao - jing LAI Ning HUANG Jian WANG Xin - yong WANG Zhi - guo(Research Institute of Soil, Fertilizer and Agricultural Water Conservation, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China)
出处
《新疆农业科学》
CAS
CSCD
北大核心
2016年第12期2280-2289,共10页
Xinjiang Agricultural Sciences
基金
自治区公益性科研院所基本科研业务费专项资金"新疆土壤主要重金属污染修复措施研究"(ky2014037)
新疆农业科学院优秀青年基金"生物炭对土壤重金属镉吸附特征的影响"(xjnkq-2014004)
自治区科技成果转化专项资金项目"核桃健康果园水肥精准管理技术集成与示范"(201454122)~~
关键词
土壤
重金属
污染评价
生态风险
soil
heavy metals
pollution assessment
ecological risk
