title: Carbon constrains fungal endophyte assemblages along the timberline.
abstract: The alpha diversity of foliar fungal endophytes (FEs) in leaves of Betula ermanii in a subalpine timberline ecotone on Changbai Mountain, China increased with elevation. There were also significant differences in beta diversity along the elevation gradient. Among the environmental variables analysed, leaf carbon significantly increased with elevation, and was the most significant environmental factor that constrained the alpha and beta diversity in the FE communities. Tree height and the cellulose, lignin, and carbon/nitrogen ratio of the leaves also affected the FE assemblages. When controlled for the effects of elevation, leaf carbon was still the main driver of changes in evenness, Shannon diversity and FE community composition. The results offered clues of the carbon acquisition strategy of the foliar FEs across this cold terrain. There was strong multicollinearity between both annual precipitation and temperature, with elevation (|Pearson r| > 0.986), so the effects of these climatic variables were impossible to separate; however, they may play key roles, and the direct effects of both warrant further investigation. As pioneer decomposers of leaf litter, variations in diversity and community composition of FE measured here may feedback and influence carbon cycling and dynamics in these forest ecosystems.
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing, 210008, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Teng
authors.initials: T
authors.lastname: Yang
authors.affiliation: Argonne National Laboratory, Institute for Genomics and Systems Biology, Argonne, IL, 60439, USA.
authors.forename: Pamela
authors.initials: P
authors.lastname: Weisenhorn
authors.affiliation: Argonne National Laboratory, Institute for Genomics and Systems Biology, Argonne, IL, 60439, USA.|Departments of Ecology and Evolution.|Surgery, University of Chicago, Chicago, IL, 60637, USA.|Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA, 02543, USA.|College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Jack A
authors.initials: JA
authors.lastname: Gilbert
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing, 210008, China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Ni
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing, 210008, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Ruibo
authors.initials: R
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing, 210008, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing, 210008, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Chu
mesh_terms: D029662:Betula / Q000382:microbiology*; D002244:Carbon / Q000378:metabolism*; D057486:Carbon Cycle / Q000502:physiology; D002681:China; D008411:Chytridiomycota / Q000302:isolation & purification / Q000378:metabolism*; D017753:Ecosystem; D060026:Endophytes / Q000378:metabolism*; D065928:Forests; D055137:Glomeromycota / Q000302:isolation & purification / Q000378:metabolism*; D008031:Lignin; D009584:Nitrogen / Q000378:metabolism; D018515:Plant Leaves / Q000382:microbiology; D014197:Trees / Q000382:microbiology
chemical_list: D002244:Carbon; D008031:Lignin; D009584:Nitrogen