Abstract:In order to understand the soil microbial community structure, its diversities of Castanopsis carlesii forests in Wuyi Mountain and Jian'ou Wanmulin Nature Reserves at northern Fujian, eastern China were investigated by phospholipid fatty acid (PLFAs) method. The results showed that soil microbial community composition in C. carlesii forest was rich, the diversity index, richness index and evenness index of soil microbial communities for the two forests were 2.92-3.01, 25.84-28.23 and 0.88-0.90, respectively. The total PLFAs, bacterial PLFAs, fungal PLFAs, actinomycete PLFAs, gram-positive bacterial PLFAs, and gram-negative bacterial PLFAs at soil depth of 0-10 cm were higher than those of 10-20 cm, and those in Jian'ou were higher than those in Wuyi Mountain. The ratio of gram-positive bacterial PLFAs to gram-negative bacterial PLFAs at soil depth of 10-20 cm was higher than that of 0-10 cm. In each soil layer, the content of bacterial PLFAs was significantly higher than those of fungal PLFAs, accounting for 46.0%-50.2% and 10.0%-11.5%, respectively, indicating that bacteria were dominated in soil microbial community. Principal component analysis showed that the difference in soil microbial community structure came from the sampling site.