七子花土壤微生物数量及呼吸速率的季节动态*

研究濒危植物七子花群落土壤微生物的生长及其呼吸速率的季节动态，结果表明：根际土壤细菌、放线菌，根围土壤细菌、真菌、放线菌的数量和土壤总呼吸速率具有相似的季节变化规律：全年呈单峰曲线变化，最大值均出现在9月份，但根际土壤真菌数量的最大值出现在10月份。土壤微生物数量受土壤含水量和温度的影响较大；土壤总呼吸速率不仅与土壤含水量和温度存在密切关系，而且与土壤微生物数量显相关，土壤微生物是土壤总呼吸的重要承担。

THE SEASONAL DYNAMICS OF SOIL MICROBIAL NUMBER AND RESPIRATION RATE IN HEPTACODIUM MICONIOIDES COMMUNITY

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