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

Cite this dataset

Tian, Chang (2022). Soil microbial biomass C, N in biocrust: A meta-analysis [Dataset]. Dryad.


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 between biocrust type, ecosystem type, and soil texture (P < 0.05). Compared with other biocrust types, lichen crust had the strongest positive effect on SMBC (822.48%). Grassland ecosystems had stronger positive effects on SMBC in biocrust than forest ecosystems, and sand and sandy loam soils had higher SMBC in biocrust than loam soils. Notably, altitude drives the positive effects of biocrust on SMBN and the negative effects of biocrust on SMBC and SMBC and SMBN ratio (SMBC: SMBN). Mean annual temperature (MAT) positively affected SMBC based on regression analysis. Further analysis revealed that SMBC and SMBN positively correlated with SOC, C: N, SWC, and urease activity and negatively correlated with pH. The random forest analysis confirmed that SOC, C: N, and altitude could be considered determinants of SMBC, SMBN, and SMBC: SMBN, respectively. Climatic factors and soil nutrients differently affected soil microbial biomass C, N and their ratio in biocrust. The high contribution of lichen crust to SMBC should be incorporated into regional and global models to predict the effects of climate change on soil carbon budgets in ecosystems worldwide.


National Natural Scientific Foundation of China

Ministry of Science and Technology of the People's Republic of China