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With the rapid development of the oil industry, the environment is also facing the problem of pollution. Diesel is one of the means of transport used most fuel, its process, its the unreasonable disposal will lead to soil pollution, serious damage to the soil environment. In this situation, the repair work undertaken. Among them, microbial remediation, development by leaps and bounds in recent years due to the economical, efficient and environmentally destructive small advantages. From Tongzhou District of Beijing, the paper soil samples were prepared in the laboratory long, wide, 1-meter high sand box device. After simulation of underground storage tanks, human lasted a year and diesel pollution from uniformly distributed points sampling, use of bioconcentration separation method, four degradation diesel strains. Finally, as the research object, this indigenous bacteria and microbial remediation of diesel contaminated soil. By taking into account the five strains of growth and environmental factors (temperature, pH, nitrogen, phosphorus source nutrients, salinity), to repair experimental study of diesel contaminated soil filter out bacteria, the main results are as follows: (1) direct separation, enrichment and purification methods, purification Four strains of bacteria diesel as the carbon source for growth: B-1, B-2, B-3 and B-4; its physiological and biochemical tests, and 16S rDNA full The sequence analysis of the identification results of four strains of B-1 is a micro genus Microbacterium sp. B-2 for a short-wave Xanthomonas Brevundimonas sp B-3 for Tetrathiobacter kashmirensis,, B-4 is a Pseudomonas genus Pseudomonas sp. . , Tetrathiobacter kashmirensis is a newly identified bacteria in the the diesel degradation of the study has yet reported in the literature. B-4 is a typical petroleum hydrocarbon degrading bacteria have been widely used in petroleum hydrocarbon degradation. (2) Indoor shaker experimental screening come to B-3, B-4's optimal growth conditions: temperature 25 ° C to 30 ° C, pH value of 7 to 7.5, the optimum nitrogen source NH4Cl optimal source of phosphorus K2HPO4 or KH2PO4, salt concentration of 0.5% to 5%. (3) two strains of biodegradation capability is superior to B-4 B-3's ability to degrade diesel fuel concentration is lower than 0.378mg / g B-3 of the degradation efficiency is lower, and concentration exceeds 0.378mg / g, the degradation efficiency increased with the concentration of diesel, B-3 degradation efficiency gradually increased to 60.98%. B-4 diesel optimum concentration of 0.252mg / g, and its degradation rate of 48.97%. When the concentration exceeds this range, the degradation rate of decline of the two strains. Bacteria tolerance range, high concentration of pollutants, toxic bacteria, inhibit microbial growth. (4) the medium of the soil system to understand the degradation of performance of the two strains. The overall degradation rate in the 30 ° C and 35 ° C, the degradation effect, B-3 is better than B-4. In the low temperature range of 20 ° C and 25 ° C, 15 days experiment, the B-3 with temperature increases, the degradation rate their was a positive correlation, B-4 the same. Therefore, the actual restoration project, about 15-20 days for microbial supplement the nutrients it with adequate nutrition play a degrading performance.
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