Isolation And Characteristics Of Soil Cadmium Tolerance And Phenanthrene Degrading Bacteria And Study On Its Influence To Diversity Of Soil Microbial Communities

Soil plays an important role in commit the various pollutants in environment. With the rapid development of the economic, more pollutant emitted to the environment, which cause more soil pollution. Polycyclic aromatic hydrocarbon (PAH) and heavy metal are important pollutants. It is important to carry out research on Eco-environmental protection and remediation to the pollution caused by their compound pollution.The research took Phenanthene (Phe) and Cadmium (Cd) as the tested pollutant. The bacteria were acquired form the soil which was polluted by PAHs and heavy metals, and the bacteria had the efficient biodegradation to degrade Phe in the presence of Cd. Then carry on a further research about degradation bacteria to study about the characteristic of degradation. Analyze the microbial functional diversity to evaluate the bioremediation and liability of the degradation bacteria W.J. Hope to offer the science basis for biodegradation about the PAHs in compound pollution's soil. Get a result as follows:With the Cd, a bacterium was separated from the compound polluted soil which can use Phe as sole carbon source. After 16S rDNA, the sequence and system evolvement analysis, this bacterium was authenticated as Alcaligenes, and named W.J.The curves of growth on different concentration of phenanthrene and cadmium showed that the period of logarithm growth is 0~20h and high concentrations of cadmium has no obvious toxicological effects to the growth.The degradation HPLC analysis results showed that the strain W.J has strong capable in degrading Phe and the degradation rates were about 45% after 5 days in the presence of Cd.Soil microbial community function was assessed with the Biolog method. The results showed that soil microbial metabolic diversity in CK was significantly higher than that in the soils in which Cd, Phe, W.J or their combination was added. It indicated that Cd, Phe has significantly negative effect on the sole-carbon-source metabolic ability of soil microbial communities, particularly when both of them were present.Application of degradation bacteria incubation makes soil microbial communities same as control. Variance analyze of soil microbial communities metabolic ability to 3l sole carbon source shows that Phe have significant negative effort on 22 out of 31 sole-carbon-source metabolic ability. After the application of degradation bacteria, only 4 sole-carbon-source metabolic ability decrease. It shows that the incubate application has a considerably effect in soil communities reversion.