Welcome to Chinese Agricultural Science Bulletin,

Chinese Agricultural Science Bulletin ›› 2008, Vol. 24 ›› Issue (12): 432-435.

Special Issue: 土壤重金属污染

• 农业资源与环境科学 • Previous Articles     Next Articles

The Effect of the Application of Sludge on Content of Heavy Metal in the Soil

  

  • Received:2008-09-17 Revised:2008-09-26 Online:2008-12-05 Published:2008-12-05

Abstract: With the rapid increase of sewage treatment plants, the disposal and the environmental impact of sewage sludge have been paid more and more attention. Land application of sewage sludge has become an important way for sludge disposal due to its lower cost and higher efficiency. But heavy metals contained in sludge are important confined factor to sludge application on agricultural land on a large scale. The investigation of speciation of metals both in sludge-amended soil and in sludge itself may help to assess the bioavailable metal fractions and the possibility of mobilization of these metals in soil. The modified three-step sequential extraction procedure proposed by the BCR was used to predict Cu Pb Cd Zn fractional distribution in rice soil amended with composted sludge. There is significant increasing on Cu,Pb,Cd,Zn contents in rice soil amended with sludge application as compared with that in the reference soil. The total contents of Cu,Pb,Zn were much lower even in soil applied with sludge at doses of 60t hm-2 than national soil environmental standards. The fractional orders of four heavy metal elements in rice soil amended with sludge was followed: residual>oxidizable >reducible >exchangeable and weak acid soluble. The stable orders of these metals in rice soils was followed: Zn>Cu>Cd=Pb.