This paper preliminary studied the movement of soil bacterial number, and the relationship with 8 kinds of ecological factors. The result indicated: soil bacterial number only appears a biggest value in one year (2.67×10-7个 individual g-1dry soil). Among 8 kinds of ecological factors, soil water content, temperature, hydrolyted nitrogen, quick acting postossium and active organic matter have straight relationship with siol bacteria, and have negative relationship with soil pH, electric conduct rate, effective phosphorus. The component analysis indicated that soil water content, temperature, electric conduct rate, active organic matter are principal effective factors.

This paper preliminary studied the movement of soil bacterial number, and the relationship with 8 kinds of ecological factors. The result indicated: soil bacterial number only appears a biggest value in one year (2. 67?10-7个 individual g-1 dry soil). Among 8 kinds of ecological factors, soil water content, temperature, hydrolyted nitrogen, quick acting postossium and active organic matter have straight relationship with siol bacteria, and have negative relationship with soil pH, electric conduct rate, effective phosphorus. The component analysis indicated that soil water content, temperature, electric conduct rate, active organic matter are principal effective factors.

The seasonal dynamics of the soil microbial growth and soil net respir ation rate were studied in the imminent Heptacodium miconioides community T he results indicate that the numbers of bacteria and actynomices of rhizosphere soil or that of bacteria ,fungi and actynomices of non rhizosphere soil as well as net respiration rate of soil maintain similar seasonal dynamics in which dis play mono peak curves and their biggest values occure in September but the bi ggest nu mber of fungi of rhizosphere soil is in October The microbial numbers of soil,e s pecially that of soil fungi ,are greatly affected by the water content and tempe rature of soil The net respiration rate of soil closely relate not only with t h e water content and temperature of soil,but also with the soil microbial numbers of non rhizosphere soil which are mostly responsible for the net respiration r ate of soil