污泥有机肥长期农用污染土壤的伴矿景天吸取修复

 在污泥有机肥长期农用土壤上种植伴矿景天,与常规的玉米-小麦-胡萝卜轮作处理比较,田间试验探讨了连续植物修复效率和污泥有机肥长期施用导致的重金属污染土壤上农产品的污染风险。结果表明,长期污泥农用土壤上农作物和超积累植物生长良好,与未施用污泥肥料处理相比,继续施用条件下“玉米-小麦-胡萝卜”轮作作物中Zn、Cd 浓度有所上升,且小麦、胡萝卜中Cd 浓度均超过国家食品安全标准。种植Zn、Cd 超积累植物伴矿景天吸取修复处理下土壤中重金属浓度显著降低,土壤全量Cd 下降56.0%;继续施用污泥条件下土壤全量Cd 下降仍可达48.4%。证明在施用污泥条件下,种植伴矿景天和农作物,能够实现污泥安全处置、促进农作物生长和污染重金属高效吸取修复的3 重目标。

Phytoremediation of cadmium/zinc contaminated agricultural soil by long term application of sewage sludge manure using Sedum plumbizincicola

To compare with the conventional maize-wheat-carrot crop rotation model, a two-year field plot experiment of planting Sedum plumbizincicola, cadmium and zinc hyperaccumulator,has been carried out to study the safe agricultural production and repeated phytoremediation efficiency of a Zn/Cd contaminated soil as resulted from long-term application of sewage sludge containing manure. The results show that crops and S. plumbizincicola grow well in the soil under long-term application of sewage sludge manure. Compared with the control, the Zn and Cd concentrations in corn-wheat-carrots crop rotation system are all increased, but the Cd concentrations in wheat and carrots exceed and fail to meet the National Food Quality Standard. The Zn and Cd concentrations in soil under S. plumbizincicola treatments decreas markedly. The phytoremediation efficiency of Cd by S. plumbizincicola is 56.0%, while for the treatment of“continuous application of sewage sludge manure”, the phytoremediation efficiency is still as high as 48.4%. So under conditions of application of sewage sludge, planting with S. plumbizincicola and corn, the triple objectives of safe handling of sludge, promoting crop growth, and high phytoextraction efficiency could be achieved altogether.