Soil total organic carbon/total nitrogen ratio as a key driver deterministically shapes diazotrophic community assemblages during the succession of biological soil crusts  

作　　者：Lin Xu Bingchang Zhang Entao Wang Bingjian Zhu Minjie Yao Chaonan Li Xiangzhen Li 

机构地区：[1]Engineering Research Center of Soil Remediation of Fujian Province University,College of Resources and Environment,Fujian Agriculture and Forestry University,Fuzhou 350002,China [2]Geographical Science College,Shanxi Normal University,Linfen 041004,China [3]Escuela Nacional de Ciencias Biológicas,Instituto Politécnico Nacional,CD.México 11340,México [4]Key Laboratory of Environmental and Applied Microbiology,CAS,Environmental Microbiology Key Laboratory of Sichuan Province,Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdu 610041,China

出　　处：《Soil Ecology Letters》2021年第4期328-341,共14页土壤生态学快报（英文）

基　　金：the National Natural Science Foundation of China(32071548,31670503,42077206);the National Key Research and Development Program of China(2018YFE0107000);the 13th Five-year Informatization Plan of Chinese Academy of Sciences(XXH13503-03-106);the National Science Fund for Distinguished Young Scholars(41925028);China Biodiversity Observation Networks(Sino BON).

摘　　要：The diazotrophic community in biological soil crusts(biocrusts)is the key supplier of nitrogen in dryland.To date,there is still limited information on how biocrust development influences the succession of diazotrophic community,and what are the most important factors mediating diazotrophic communities during biocrust succession.Using the high throughput nifH amplicon sequencing,the diazotrophs in soils at different developmental stages of biocrust were comparatively studied.The results evidenced the decreases of TOC/TN ratio and pH value with biocrust development.Nostoc and Scytonema were the most dominant diazotrophic genera at all biocrust stages,while Azospirillum and Bradyrhizobium were abundant only in bare soil.Diazotrophic co-occurrence networks tended to be less complex and less connected with biocrust succession.The soil TOC/TN ratio was the most dominant factor mediating diazotrophic diversity,community composition and assembly processes,while diazotrophic-diversity and NO3–-N/NH4+-N ratio were positively correlated with the nitrogenase activity during biocrust succession.This study provided novel understandings of nitrogen fixation and succession patterns of diazotrophic community,by showing the effects of biocrust succession on diazotrophic diversity,community composition,community assembly and co-occurrence networks,and recognizing TOC/TN ratio as the most dominant factor mediating diazotrophs during biocrust succession.

关 键 词：Biological soil crust succession nifH amplicon sequencing DIAZOTROPHS Community assembly Co-occurrence networks 

分 类 号：S15[农业科学—土壤学]