Bacterial Diversity Of Haloalkaline Lakes In Desert Hunshandake In Inner Mongolia

Haloalkaline lake is one kind of extremes, which is distributed widely in China especially in Inner Mongolia. However the extremphiles are not yet studied enough in these environments. This paper characterized the structure of bacteria community and their diversity of water samples of haloalkaline lake Sanggedalai, Dagenao and Zhagesitainao in Desert Hunsandake, using pure culture and 16S rDNA library construction.The results showed that, the isolates from Sanggedalai were Gammaproteobacteria, Bacilli and Actinobacteria, in which the former two were the dominant with a proportion of 46.2%. Similarities of two strains S03 and S09 were very low to the known type strains, with highest homology of 72% and 88.7% respectively, for which these were probably new bacteria ofγ-proteobacteria. Two bacterial groups were isolated from Dagenao and Zhagesitai, namely Gammaproteobacteria and Bacilli; the former accounting for 80%, was the dominant group in Dagernao; the proportions of the two groups was nearly equal in Zagesitai. One strain had a highest homology of 84.3% with the known, for which the isolate maybe is a new strain of Bacilli from Dagernao.In 16S rDNA gene library, microbial diversity index of salt lake in Sanggedalai was 0.8916, the distribution evenness of different species was 0.2972, species richness was 1.6368 and the Gammaproteobacteria is the dominant bacteria. In this environment microorganism's species are quite unitary, and the unknown strains are very few. Microbial diversity index of saline lake in Dagenao was 1.9230, the distribution evenness of different species was 0.4312, species richness was 4.5712 , Cyanobacteria were the dominant bacteria and was unique class of population in the environment, accounting for 53% of the entire community. In Dagenao, there were 13% of an unknown bacteria, indicating that the environment existed certain new microbes. Microbial diversity index of salt lake in Sanggedalai was 3.7281, the distribution evenness of different species was 0.6201, species richness was 12.3442, these indicators suggested that the microorganisms in the environment had a high species diversity, high species richness, and distributed more uniformly. Also, there were a lot of uncultured microorganisms in a high percentage of 56.6% in the lake.