| With the rapid development of the population quantity, the demand of grain by human being is enlarged day by day, and a lot of pesticide and herbicide and other toxic or harmful materials were used in the agriculture. The half-life of these materials are all very long, in the meanwhile, most of them have biological toxicity, so they could stay in the environment and keep destroying the ecological environment, especially harm the animals, plants and human seriously. So how to establish an efficient, safe and cheap way to deal with these pollutants is a focus over the worldwide. This study took the atrazine, a kind of herbicide which is widely used in northen parts of China, as the research object. According to analyze the influence of the degrading conditions and research the atrazine degrading bacteria immobilized technology, to find an efficient and feasible way to deal with the atrazine which residue in the soil. The main study contents and results as follows:1) The study built a serious accurate, effect method to extract and analyze atrazine which in the solution and soil. Used the gas chromatograph(GC) which equipped with a fused silica chromatographic column(300mm×0.53mm) packed with 14% OV-1701 as the detection tools, to detect the content of atrazine. Choose the CHCl3 as extractant to extract atrazine in the solution. The recovery rates were ranged from 99.45%-99.84%. Choose the mixed solution (methanol: water=9:1) as the extractant to extract atrazine in the soil, the process include immersion, oscillation, air pump filtration, distillation and extraction. The recovery rates were ranged from 91.89%9-97.68%. The two results shows, the methods which the study chose are accord with the demand of pesticide residue analysis.2) The study researched the two high effect atrazine degrading bacteria J2 and J6 which isolated by our own laboratory, and research the influence to the growth and degrading effect of J2 and J6 by the different external conditions. The result showed:the best degrading conditions of J2 and J6 is 30℃and the pH is 73) The study tested the influence of the different immobile material and methods to the degrading effect of high effect atrazine degrading bacteria J2 and J6. The study chose the sodium alginate, PVA and vermiculite as the research object. And found that the sodium alginate embedding method is the best immobile way to the atrazine degrading bacteria. The best immobile condition of both the two strains is that the concentration of sodium alginate is 2%, the concentration of CaCl2 is 4% and the particle size is 2.13mm. But the result of variance analyse and F test showed that when the concentration of the sodium alginate in the range among 1%-3%, the concentration of CaCl2 in the range among 2%-4%, the particle size among 1.70mm-2.13mm, they are not influence the degrading rate significantly.4) The study researched the degrading characters in different conditions of the two high effect atrazine degrading bacteria J2 and J6 which after immobilization. The best temperature of the two degrading bacteria which after immobile is both 30℃. The best pH of J2 is 7, and when pH is 6-10, the degrading rate of J6 is in a high position, over 90%. Compare with the degrading bacteria which didn't immobile showed that both of the degrading bacteria all have residence to the too high or too low temperature and pH value. It means the immobile method could improve the tolerability of the degrading bacteria to the bad environment.5) The study researched soil remediation by the degrading bacteria primarily. After immobile processing, both of the atrazine degrading bacteria J2 and J6 showed the high efficient in the soil. The degradation rate of the atrazine in the soil is over 98%. The result showed the atrazine degrading bacteria J2 and J6 which after immobile could degrade the atrazine in the soil high efficiency.
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