**5. Conclusions**

Our findings sugges<sup>t</sup> that habitat do not affect the total biomass of microorganisms, but microbial community composition is significantly influenced by the habitat microenvironment, which might alter the decomposition rate of litter. Results here implied that the number of individual PLFA in the forest floor and intermittent stream was significantly higher than that in the stream in the whole decomposition period. Compared with the late stage of litter decomposition, the difference of individual PLFA concentrations among the three habitats was reflected in the forest floor and aquatic system in the early stage of litter decomposition, but it was mainly reflected in the headwater stream and the intermittent stream in the late stage of litter decomposition. Interestingly, we linked the relationship between microbial community structure and litter decomposition and found that the microbial community showed the greatest correlation with the litter decomposition rate in streams. In conclusion, our results further clarify the dynamics of microbial communities during the litter decomposition in different habitats.

**Author Contributions:** Conceptualization, H.G., F.W. and X.Z.; data curation, H.G.; formal analysis, H.G.; funding acquisition, F.W. and D.W.; investigation, H.G., X.Z., W.W., L.Z. and R.W.; visualization, H.G.; writing-original draft, H.G.; writing-review and editing, H.G., F.W. and D.W. All authors have read and agreed to the published version of the manuscript.

**Funding:** The National Natural Science Foundation of China, gran<sup>t</sup> number 32001965, 32171641 and 32101509 which funded this study.
