城市污泥与湖泊底泥土地利用对土壤-植物系统中养分及重金属Cd、Pb的影响

Effects of Land Utilization of Municipal Sludge and Lake Sediment on Nutrients and Heavy Metals(Cd,Pb) in Soil-Plant System

采用田间小区试验,探讨了城市污泥与湖泊底泥土地利用对土壤-植物系统中养分及重金属Cd、Pb的影响。结果表明,城市污泥与湖泊底泥能有效增加土壤养分含量;重金属Cd、Pb仅累积在土壤耕层,难以向下迁移;随施用量的增加,小麦籽粒产量及其对养分的吸收量均随之增加,但仍有大量养分存留在土壤中;植株对重金属的富集顺序表现为根系>茎叶>籽粒,Cd>Pb,其中,籽粒中重金属Cd、Pb含量均未超出我国食品中重金属限量的卫生标准;如果该污泥、底泥分别以100,200 t/hm2的施用量施入土壤,可以连续施用5 a和6

The plot experiments were conducted to study the effects of land utilization of municipal sludge and lake sediment on nutrients and heavy metals （Cd,Pb） in soil-plant system. The results showed that content of nutrients could be increased in the soil by application of municipal sludge and lake sediment, heavy metals of Cd,Pb accumulated in the surface soil layer without migrating downward into deep soil layer. With the increasing of application of municipal sludge and lake sediment on soil, the yield of wheat seed and the content of nutrients, absorbed by wheat, both increased, but mass of nutrients accumulated in the soil, the accumulation of heavy metals were in an order： root〉stem〉seed, Cd〉Pb, the content of heavy metals of Cd,Pb in wheat seed were not exceeded the National Control Hygienic Standard for Foods, municipal sludge and lake sediment could be applied 5 years and 6 years on soil continuously, even the amount of application was 100 t/hm^2 and 200 t/hm^2.