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Reclaimed water irrigation is one of the potential ways of solving the shortage of water resources,and the pollution risk on migration behavior of heavy metals in the soil which are irrigated by reclaimed water and the related soil surface is still short of research. Through the experimental study of different kinds of water irrigation methods on vegetable,it can be concluded that compared with sewage irrigation and tap water irrigation,reclaimed water irrigation does not pollute the soil,and it greatly saves the cost of water resources,and even provides a large number of growth elements for vegetables. The results show that after leaching by reclaimed water for 60 days,Cr,Cd,As,Hg,Pb,Ni,Zn and Cu from reclaimed water are enriched in soil to a certain degree,but with the leaching time extending,concentrations of the heavy metal remain stable. The variation of heavy metal content in soil irrigated by reclaimed water is small in vertical depth,basically showing a horizontal trend. According to Soil Environmental Quality Standards( GB15618- 1995),soil irrigated by reclaimed water does not exceed the standard,better than soil quality standard of planting vegetables.
Reclaimed water irrigation is one of the potential ways of solving the shortage of water resources, and the pollution risk on migration behavior of heavy metals in the soil which are irrigated by reclaimed water and the related soil surface is still short of research. study of different kinds of water irrigation methods on vegetable, it can be threaded that compared with sewage irrigation and tap water irrigation, reclaimed water irrigation does not pollute the soil, and it greatly saves the cost of water resources, and even provides a large number of growth elements for vegetables. The results show that after leaching by reclaimed water for 60 days, Cr, Cd, As, Hg, Pb, Ni, Zn and Cu from reclaimed water are enriched in soil to a certain degree, but with the leaching time extending, concentrations of the heavy metal remain stable. The variation of heavy metal content in soil irrigated by reclaimed water is small in vertical depth, basically showing a horizontal trend. Accord ing to Soil Environmental Quality Standards (GB15618-1995), soil irrigated by reclaimed water does not exceed the standard, better than soil quality standard of planting vegetables.