污泥农用对土壤和作物重金属累积及作物产量的影响

以3 a定位试验为基础，比较3种不同处理的污泥肥料（消化污泥、污泥堆肥及污泥复混肥）农田施用下土壤养分、土壤和作物籽粒中Mn、Cu、Zn、Pb、Cd 5种重金属的积累以及作物产量的变化情况，以阐明污泥农用对土壤及作物的影响。研究表明，3种污泥肥料提高了土壤中氮素和有机质的含量；与空白和普通化肥处理相比，3种污泥肥料增加了土壤中Mn和Cu的含量，而对土壤交换态重金属含量没有显著影响；3种污泥处理均增加了小麦籽粒中Zn的含量；相对普通化肥处理，3种污泥肥料处理对小麦和玉米产量均无显著影响。合理施用污泥肥料可以有效地提高作物产量；污泥肥料施用对土壤重金属有一定累积效应，但短期施用对土壤比较安全。

Effects of farmland application of sewage sludge on crop yields and heavy metal accumulation in soil and crop

Based on a 3 years located experiment, the heavy metals such as Mn, Cu, Zn, Pb, Cd concentration of soil and crop and crop yields were investigated for the different treatments on farmland application of sewage sludge, by comparing soil nutrient, heavy metal contents of soil and crop and crop yields, the treatments included three different kinds of sewage sludge, namely digested sludge, sludge compost and sludge compound fertilizer. The results indicated that three kinds of sewage sludge could significantly increase the contents of total organic matter and total nitrogen in soil. Compared to treatments of control and ordinary chemical fertilizeres, three different kinds of sewage sludge could increase Mn, Cu contents in soil, but had not significant influence to exchangeable heavy metals in soil. Three kinds of sewage sludge could increase Zn contents in wheat grain. Compared to the ordinary chemical fertilizer, the use of three different kinds of sewage sludge had no significant effect to yield of wheat and maize. Reasonable use of sewage sludge can be effective in raising crop yield. Sewage sludge application had a certain cumulative effect on soil heavy metals, but short-term application was relatively safe.