Study On Metabolism And Transimission Of The Pathogenic Bacteria In Soil After The Treated Water Irrigation

Because of the development of the social, the result of citifying process and the growth of the human population, water crisis had become one of the important constraints. The treated water which could be used for the irrigation has important significance to alleviate water crisis.Studies have shown that through the teated water irrigation, the crop production has increased, but the water discharge different with irrigation demand in space and time, the treated water contain complex components. The pathogenic microorganism is one of them. These pathogenic microorganisms have an enormous impact on the soil, plants and human health. Therefore, the study of the metabolism and transmission could be used for the basic research and premise work of security identification.Abut the metabolism on the soil after the treated water irrigation, the comprehensive comparative experiment was designed for the analysis research. The paper analysis the environmental factors which contains the particle size distribution, moisture content, pH, temperature and nutrients.On the other hand, The changes of the pathogen microorganism quantity following with one environmental factor when the other environmental conditions unchanged were determined ,the critical point of metabolism environmental factor was found;On the other hand, the comparison of the environment effects were made, the comparison could be used for the reference of treated water irrigation,and could gave some advice on how to take measures to reduce health risks;Finally, puts forwards some suggestions about the artificial control measures which was used to reduce the health risk of the pathogen metabolism and bring down the cost of sewage treatment.The study of adsorption consists of two parts. The two parts are the soil water in saturated and unsaturated. When the soil water in saturated,the E. coli was uesed for the study model, a dynamic adsorption curve of E. coli was build up.With the help of the adsorption curve, the quantitative division about the pathogen was completed. In this process,these microorganisms were divided into three parts(the direct harmful microorganisms,the potentially harmful microorganisms and the no harmful microorganisms ),so the adsorption of soil could be accurately predicted. When the soil in unsaturated, the effect of the soil depth and the pathogen microorganisms concentration on the adsorption of the soil was determined,and the study supplied a theoretical foundation for the bacteria health risks.Through the studies of metabolism and transmission, these environmental factors ( such as pathogens temperature, PH value, moisture content, nutrients, particle size distribution )and impact factors of pathogen transmission (such as the concentration of wastewater pathogens, the volume of reversible adsorption, and the separated from the soil pore) serve as evaluating indicator. With the help of evaluating indicators,the evaluation system of the pathogen hazards in sewage irrigation was set up. On the basis of the evaluation system, comprehensive index was used to evaluate the pathogen hazards in sewage irrigation...