西安市西郊菜园土壤重金属污染评价

Evaluation of Soil Heavy Metal Pollution in the Western Suburbs of Xi'an Garden

在西安市西郊菜园区采集土壤样品,测定土样中Zn、Pb、Cd和Cr 4种重金属元素的含量,分别为138.79、39.11、0.30、67.63mg/kg。利用单因子指数法、内梅罗综合因子指数法和地积累指数法,对菜园土壤重金属的污染情况进行评价。结果表明,3个采样区的土壤受到不同程度的污染,其中Zn为中度污染,Pb、Cd为轻度污染-中度污染,Cr为无污染-轻度污染,综合污染程度依次为三民村>北石桥>鱼化寨西村。同时,测定重金属各种形态含量。通过生物有效性分析,发现4种重金属中Zn和Pb对植物的潜在威胁较大,Cd对植物的影响较小,Cr会对植物造成危害。

By collecting samples in western suburbs garden of Xi＇an, the content of heavy metals in soil was investigated. The content of soil samples of Zn, Pb, Cd and Cr were 138.79, 39.11,0.3 and 67.63 mg/kg. The circumstances of heavy metal pollution were evaluated with sin- gle factor index method, Nemerow comprehensive index method and geoaccumulation index method. The results showed that the three soil sam- piing areas affected to different degrees of pollution ： Zn was moderately pollution, Pb, Cd was light pollution to moderately pollution and Cr was pollution to light pollution, pollution levels from high to low is Sanmin Village 〉 Beishi bridge 〉 Yuhuazhai Village. The content of various forms of heavy metals were determined, through biological effectiveness analysis, it was found that Zn and Pb had high potential threats on plant, Cd had little effect on plant. Cr will cause harm to the plant.