Soil microbial biomass C, N in biocrust: A meta-analysis

The biological soil crust (biocrust) has many crucial ecological functions in dryland ecosystems. Differentiation of soil microbial biomass in different ecosystems’ biocrust under various climatic and soil conditions remains unknown, restricting our knowledge of biocrust microbiomes regulating terrestrial carbon and nitrogen cycling globally. We selected 255 paired observations from 45 global study sites for meta-analysis to quantify the effect of biocrust type, soil texture, and ecosystem type on soil microbial biomass in biocrust and identify the underlying impact factors. The results showed that biocrust had significantly higher soil microbial carbon and nitrogen contents (SMBC and SMBN, respectively) than bare (non-crust) soil (P < 0.05). Biocrust also significantly increased total nitrogen (TN) (143.68%), soil organic carbon (SOC) and TN ratio (C: N) (9.93%), and soil water content (SWC) (60.18%), and decreased pH (0.72%) (P < 0.05). Overall, the SMBC significantly differed b..., ,