炼铜厂对周边土壤和作物体内重金属含量及其空间分布的影响

Effect of copper refining on spatial distribution of heavy metal in surrounding soils and crops?

对富阳污染比较严重的一个小高炉周围农田的土壤进行了调查分析,结果发现该区土壤的重金属污染主要是As、Cd、Cu、Pb和Zn这5种元素,尤其是Cu、Pb、Zn,分别可达1775.6、1140.1和621.3mg/kg;在土壤重金属水平分布方向上,土壤受其污染的程度随污染源距离的增加而降低,到300m处已基本没有影响,在土壤重金属垂直分布方向上,其对土壤表层污染较为严重.并发现土壤微生物碳量与土壤重金属的含量有显著的负相关;在大田中采取的一些农艺改良措施虽然降低了土壤中有效重金属含量并提高了产量,但未能使水稻谷粒内的重金属含量达到国家卫生标准.

Investigation and analysis of soils and plants in the heavily polluted farm field near a smelting factory showed that the main elements in the pollutant included As,Cd,Cu,Pb and Zn, among which Cu,Pb and Zn content in soil were very high, reaching 1775.6, 1140.1 and 621.3 mg/kg respectively; The metal content in the soil decreased with increasing distance from the smelting factory and reached normal level at a distance of about 300 m. Heavy metal concentrations were relatively high at the surface soil layer (15 cm), and decreased with increasing soil depth. Soil microbial carbon content of surface layer was closely related to the concentration of heavymetal in soils. For the purpose amendment, some agricultural measures were adopted in a field experiment, which effectively reduced available heavy metal content in the soil and increased the crop yield. However, following these treatments, the heavy metal concentrations of grains did not attained the national sanitary standards.