Adsorption And Degradation Of Atrazine In Soil By The Charcoal Enriched With Consortia Of Degradation Bacteria

The application of immobilized microorganism has become the hotspot that more and more scholars are reserching.It is widely used in industry,agriculture, medicine,environment protection and energy exploration etc.And has widely development foreground.On the basis of comprehensively.Analyses soil environment of our country soil,the paper works out the organic contaminated soil-purifide technique.With immobilized microoganism on charcoal method to make organism degradation experiments,the motion is to develop a new approach to improve organic contaminated soil degradation rates.The main items as following:1.Sludge witch comed from zhong shan chenmical plant aerobisis demesticating,two strains are able to grow on atrazine as nitroge source and have highly effctive degradation ability,labelled 7 and 32.2.The growth characteristic study of 7 and 32 strains indicated that they enter into the stage of logarithm in 12 hour and stationary in 36 hour.The most appropriate growth condition of the two strains were stuided:the optimal pH to two strains are between 8.0-9.0, and they adapt for growth in alkaline condition and are restrained in metaaeide condition. But to 7 strain,the effect of temperature is not obvious;to 32 strain,the optimal temperature is between 20-30℃,the growth begain decline.In the meantime,the physiological and biochemical character were indentified.3.The adsorption-desorption of atrazine on charcoal was studied.The results showed that charcoal had great adsorption ability.The meawhile,adsorption test was carried on by red earth with 2%carbon content and shajiang black soil with carbon content to atrazine with different concentrations.The results indicated the absorption quantity of atrazine was more when charcoal was put in soil containing different concentrations atrazine,comparing with that in soil solutions without charcoal.The porosity of charcoal have obvious enrichment to atrazine and the enrichment capability of charcoal is more than soil.Charcoal as carrier to microorganism immobilization according to the strong adsorption quantity of charcoal, the charcoal adsord and degrade atrazine in soil after microorganism is immobilized on charcoal.The meanwhile,charcoal have no secondary pollutin,so it is can be as carbon source to growth demand of crop.All these prove that charcoal can be as ideal carrier to microorganism immobilization.4.The biodegradation of atrazine with 40 mg/kg concentrations in soil by immobilized single strain and mix strain was studied.The results showed that the biodegradation capacity of atrazine by immobilized microorganism in carbon was improved compared with free microorganism,the degradation rate of immobilized microorganism to atrazine within reach 60%,but 35%to free microorganism.meanwhile,the effect of sterilization to biodegradation capacity of atrazine is less.Biodegradation capacity of immobilized microorganism was more than indigene bacterium.5.Atrazine metabolites were detected and identified by LC-MS.Atrazine metabolites were detected and identified by LC-MS.The result suggests that the isolate 32 bacteria can metabolize atrazine into Hydroxyatrazine,Hydroxydeisopropylatrazine and Hydroxydeethylatrazine;and 7 bacteria can metabolize atrazine into Deethylatrazine.