To determine the relationship between forest litter and soil microbial community structure,the decomposition effects of the main species leaf litter in Loess Plateau Ziwuling Mountain on the genotypic diversity of soil microbial communities were studied using the PCR-DGGE method. The diversity analysis results indicated that the tendency of the Shannon-Wiener index of soil microbes treated by single leaf litter was as follows: Quercus liaotungensis(3.54)>Pinus tabulaeformis(3.49)>Betul platyphylla(3.30). The microbial community diversity of soils treated by different leaf litter varied:the diversity in some pots increased, while that in others decreased. The highest Shannon-Wiener index was found in the mixed leaf litter treatment of Quercus-liaotungensis-Pinus-tabulaeformis-Betul-platyphylla. Cluster analysis results indicated that eight kinds of soil samples were divided into four groups: the mixed leaf litter treatment (S2, S5, S3 and S4), the single leaf litter treatment (S7 and S8), the single leaf litter treatment (S6), and none-leaf litter treatment (S1). These results showed that the soil bacterial community structure changed significantly after it was treated by leaf litter. The change in the microbial community structure varied differently between single treatment and mixed treatment. These changes were caused by different types of forest litter and their interaction.

leaf litter; microbial community; microbe; soil