北京市通州污灌区土壤环境质量监测和蔬菜重金属污染状况研究

Monitoring of soil environment pollution and vegetable contamination by heavy metals in Tongzhou irrigation area of Beijing city

通过对北京市通州污灌区土壤现状调查与蔬菜重金属污染监测,结合土壤环境质量标准、食品卫生标准及污灌区污染历史,分析对比该区土壤和蔬菜重金属污染状况及其变化。结果表明,本次监测通州污灌区土壤中重金属平均含量均达到土壤环境质量标准(GB15618-1995)中二级标准限量。对照土壤中的重金属Cu、Pb、Cr、Cd和As均达到土壤一级标准。凉水河两岸和通惠北干渠中重金属含量均高于对照土壤,说明污灌区污水灌溉已使土壤受到一定程度的污染。与二十世纪70年代末监测结果相比,土壤中多数重金属含量处于上升趋势。污灌区蔬菜重金属含量监测结果表明,其含量水平均达到食品卫生标准,说明污灌区蔬菜尚未受到严重污染。

Based on the inspection about Tongzhou sewage irrigation area of Beijing city at south-eastern suburb and according to soil environment quality standard, food sanitation standard and by comparing the pollution status with that in 1970s, the status and content changes of heavy-metals in soil and vegetables were obtained. The heavy-metal average content of soil of the sampled area reached the second grade standard of soil environment quality standard （GB15618-1995）. The content of Cu, Pb, Cr, Cd and As of soil for reference reached the first grade standard. The heavy-metal content of soils from the banks of Liangshui River and the main trench of Tonghuibei were larger than that of the background soil, which indicated that the soils of the sewage irrigation area was contaminated by sewage irrigation. The content levels of most of heavy-metals in soils tended to increase by comparing with the status in 1970s. The content of Cu, Pb, Cr, Cd and As in vegetable reached the food sanitation standard, which suggested that the vegetable from above sewage irrigation area was not heavily contaminated.