川中丘陵土壤重金属元素潜在生态风险评价与预警

以《土壤环境质量标准》(GB 15618-1995)(pH>7.5)为评价标准,对四川省内江市双桥乡土壤重金属As,Cd,Cr,Cu,Hg,Ni,Pb,Zn的污染风险开展了评价工作:以一级标准(自然背景值)为计算依据,对研究区进行了土壤重金属潜在生态风险评价和生态风险预警.通过研究发现:依据国家二级标准(pH>7.5),研究区土壤重金属污染风险均处于无污染级;潜在生态风险评价结果显示,土壤较高水平的Cd在构成环境污染的同时,也构成了严重的生态危害;从生态风险预警评估综合评价指数来看,研究区的土壤重金属总体处在低警级别,但部分样点的单项风险指数级别稍高,应该加强对个别重金属的风险防治.

Content of Heavy Metal Elements of Ecological Risk Assessment and Early Warning in the Hilly Region of Sichuang Central Section

The pollution of soil heavy metals,including As,Cd,Cr,Cu,Hg,Ni,Pb,Zn,is assessed according to the Standard of Soil Environment Quality(GB15168-1995).The soil heavy metal potential ecological risk assessment and ecological risk warning is calculated according to the Standard of Soil Environment(natural background value).The result shows that the soil heavy metal pollution risk in the pollution-free level which based on the national secondary standard(pH>7.5);the potential ecological risk assessment result shows that soil Cd to a higher level in an environmental pollution at the same time,pose a serious ecological hazards;from the composite index of the ecological risk warning assessment of soil heavy metals in general for the entire study area in the low police level,but has been part of the sample points of a single risk index slightly higher level,should strengthen the control measures for individual heavy metals.