| Soil heavy metal pollution caused widespread concern because it is harm for ecological environment and creature. Research and development environmental protection and efficient repair methods of soil heavy metal pollution, control input of heavy metal pollutants become the hotspots. The main contents of this paper were: (1)The test would be developed by putting amendments into the medium block, in order to reduce the Cd uptake of plants. With green peppers, cabbage and corn as tested plants, We studied plant growth and uptake of cadmium, by changing the medium blocks in size and adding different concentrations and different types of amendments. (2) We study effect of sewage sludge compost application on heavy metals accumulation in soil and wheat shoots.The main results were as follows:(1) Medium block reduced the plant uptake of cadmium. Cadmium content of overground part of green peppers, cabbage, corn decreased by 5.90% -44.70%, 5.30% -42.8%, 14.72% -49.18%; root cadmium content decreased by 17% -45.70%, 13.90% -61.40% , 1.22% -45.06%.(2) The appropriate concentration of amendments was good for growth of plant. 40mg/kg of rare earth promote the growth of green pepper and cabbage. Fruit fresh weight of green pepper increased of 15.67%, shoot dry weight increased of 19.90%, root dry weight increased of 7.07%; Economic yield of cabbage increased by 9.84% -23.81%, shoot dry weight increased by 9.96% -18.35%. Medium block by adding attapulgite 10g/kg and 30g/kg promoted the growth of green pepper, fruit fresh weight increased 1.31% and 10.97%, shoot dry weight increased by 1.43% -11.11%. As to medium block with added amendments, shoot dry weight were all 1.85-2.42 times higher than the control, in which the case 30g/kg humic acid, 10mg/kg rare earth, 10g/kg and 50g.kg zeolite, corn on the ground dry weight was significantly higher than the control.(3) Adding appropriate concentrations of amendments to medium block increased the role of medium block on reducing plant uptake of cadmium. In the test of green pepper, by adding humic acid, cadmium content of green pepper of overground part decreased by 5% -13.75%, content of cadmium in the roots decreased by 25.60% with 10g/kg handling; As to the case of 10g/kg, 30g/kg and 50g/kg attapulgite, cadmium content of the overground part decreased by 0.39% -23.68%, the root decreased by 5.96%-23.78%. On the test of cabbage, by adding 30g/kg attapulgite, root cadmium content decreased by 1.68%, meanwhile, 200mg/kg of rare earth, root decreased by 7.82%. After testing ground corn added amendments, Cd content reduced by 13.94% -40.4%; corn roots decreased cadmium content 9.49% -44.39%. Humic acid of 30g/kg and zeolite of 10g/kg were better than other treatments.(4) Medium block of different sizes had different role of reducing plants absorbing cadmium. Absorption content of cadmium was as follows: small block> general block> thick block> large block. Large block significantly reduced the content of Cd of corn.(5) Zn, As content in soil and wheat increased with the application of sludge compost fertilizer; Hg content increased in the soil, while had no improved in wheat; Cu, Cd content of soil increased, and it did no relationship with sluge compost application in wheat.
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