Liu Guangxiu

Quantitative characteristics of microorganisms in permafrost at different depths and their relation to soil physicochemical properties

The microorganisms in permafrost could live in cold environment through the coadapted physicochemical process,which exists between microorganisms in permafrost and permafrost environment.In this paper,the relation between microbial number and soil physicochemical properties of permafrost at different depths at the headwaters of the urumqi River is analyzed by using fluorescence microscopy counting and oligo-culture techniques.Totally,20 samples from a 200-cm permafrost core were used as study materials.It is found that the number of cultivable bacteria has a significant positive correlation with soil water content,total carbon and total nitrogen concentrations,and a significant negative correlation with pH value.Meanwhile,the ratio of cultivable bacteria to total cell number decreases with depth.The results demonstrate that the number of cultivable bacteria in permafrost is closely correlated with soil physicochemical properties and depositional age.