Microorganisms in permafrost can live in cold environments due to coadapted physicochemical processes in this environment. In this paper, the relation between microbial number and soil physicochemical properties at the headwaters area of the Urumqi River is analyzed by using fluorescence microscopy counting and oligo-culture techniques. In total, 20 samples from a 200-cm permafrost core were used as study materials. The study reveals that the number of culturable bacteria has a significantly positive correlation with soil water content, total carbon and total nitrogen concentrations, and a significantly negative correlation with soil pH value. In addition, the ratio of culturable bacteria to total cell number decreases with depths. The results demonstrate that the number of culturable bacteria in permafrost is closely correlated with soil physicochemical properties and depositional age.
Surface snow samples of different altitudes and snow pit samples were collected from Glacier No. 1 at the Urumqi River Head, Tianshan. Denaturing gradient gel electrophoresis （DGGE） was used to examine the diversity and temporal-spatial characteristics of eukaryotic microorganisms with different altitudes and depths. Results show that the eukaryotic microorganisms belong to four kingdoms--Viridiplantae, Fungi, Amoebozoa, and Alveolata. Among them, algae （especially Chlamydomonadales） were the dominant group. The diversity of eukaryotic microorganisms was negatively correlated with altitude and accumulation time, but positively correlated with 8180 values. These results indicate that temperature is the main factor for the temporal-spatial change of eukaryotic microorganisms, and the diversity of eukaryotic microorganisms could be an index for climate and environmental change.
Wei ZhangGaoSen ZhangGuangXiu LiuZhongQin LiLiZhe An
