Figure 4: (A) Detrended correspondence analysis (DCA) of soil microbial communities using 454-pyrosequencing data from A, B, and C soil sample, respectively. Detrended correspondence analysis of all communities indicated that the microbial community and structure of sample C was different from the microbial community of sample A and B. The values of Axis 1 and 2 are percentages that the corresponding axis can explain. (B) Hierarchical clustering analysis of microbial communities in the three sites (sample A, sample B and sample C) in the city of Lanzhou based on 454-pyrosequencing.