Study On Fixing And Repairing Effect Of Solanum Nigra Combin Ed With Microbial Agent On Soil Cadmium Element

With the continuous development of industrial system in recent years,heavy metal polluta nts are concealed in soil and difficult to be found,but they do great harm to human health,hum an settlements,agricultural production and water and atmosphere.In this paper,Bacillus subtilis,Enterobacter cloacae,Hafnia alvei and Bacillus cereus were combined with four microbial ag ents.Combined remediation with cadmium-tolerant plant Solanum nigra,and observed the fixe d remediation effect of compound bacterial-Solanum Nigra repair method on soil cadmium ele ment.Compared with Solanum Nigra repair method,the plant height,chlorophyll content,supe roxide dismutase activity,catalase activity,malondialdehyde and other related indicators were a nalyzed,and the following conclusions were reached:(1)The preparation and dosage of complex bacterial agent is as follows:Bacillus subtilis d osage(A)was 6.673%,Enterobacter cloacae dosage(B)was 7.860%and Hafnia alvei dosage(C)was 7.097%.When Bacillus cereus dosage(D)was 7.474%,the removal rate of effective ca dmium ions in soil reached 64.346%.(2)Soil cadmium ion concentration is 0-20mg/kg has promoting effect to the growth of the black nightshade,but with the increase of the content of heavy metals will be inhibited the grow th of the black nightshade phenomenon.Soil cadmium ion concentration of 20 mg/kg,deadly ni ghtshade plant height growth than soil cadmium ion concentration of 1.5 mg/kg will be 20%hig her,about 35.8%higher chlorophyll content,catalase activity will be 15.1%higher,superoxide dismutase will be 11.4%higher.(3)The change amount of plant height,chlorophyll content,superoxide dismutase activity and catalase activity of Solanum solanum combined with complex bacterial agent in the repair g roup were significantly higher than those of the repair group,but with the passage of time,all s howed a downward trend.Under the action of complex bacterial agent,the accumulation of hea vy metal Cd2+in Solanum mongolica was less than that in Solanum mongolica repair group,an d the removal rate of available Cd2+in soil reached 77.97%.