title: The microbial gene diversity along an elevation gradient of the Tibetan grassland.
abstract: Tibet is one of the most threatened regions by climate warming, thus understanding how its microbial communities function may be of high importance for predicting microbial responses to climate changes. Here, we report a study to profile soil microbial structural genes, which infers functional roles of microbial communities, along four sites/elevations of a Tibetan mountainous grassland, aiming to explore the potential microbial responses to climate changes via a strategy of space-for-time substitution. Using a microarray-based metagenomics tool named GeoChip 4.0, we showed that microbial communities were distinct for most but not all of the sites. Substantial variations were apparent in stress, N and C-cycling genes, but they were in line with the functional roles of these genes. Cold shock genes were more abundant at higher elevations. Also, gdh converting ammonium into urea was more abundant at higher elevations, whereas ureC converting urea into ammonium was less abundant, which was consistent with soil ammonium contents. Significant correlations were observed between N-cycling genes (ureC, gdh and amoA) and nitrous oxide flux, suggesting that they contributed to community metabolism. Lastly, we found by Canonical correspondence analysis, Mantel tests and the similarity tests that soil pH, temperature, NH4(+)-N and vegetation diversity accounted for the majority (81.4%) of microbial community variations, suggesting that these four attributes were major factors affecting soil microbial communities. On the basis of these observations, we predict that climate changes in the Tibetan grasslands are very likely to change soil microbial community functional structure, with particular impacts on microbial N-cycling genes and consequently microbe-mediated soil N dynamics.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Yang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
authors.forename: Shiping
authors.initials: S
authors.lastname: Wang
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China.
authors.forename: Depeng
authors.initials: D
authors.lastname: Xu
authors.affiliation: Department of Botany and Microbiology, Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA.
authors.forename: Hao
authors.initials: H
authors.lastname: Yu
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China.
authors.forename: Linwei
authors.initials: L
authors.lastname: Wu
authors.affiliation: Key Laboratory of Adaption and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China.
authors.forename: Qiaoyan
authors.initials: Q
authors.lastname: Lin
authors.affiliation: 1] Key Laboratory of Adaption and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China [2] Shapotou Desert Experiment and Research Station, Cold and Arid Regions and Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, China.
authors.forename: Yigang
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, China.
authors.forename: Xiangzhen
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Botany and Microbiology, Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA.
authors.forename: Zhili
authors.initials: Z
authors.lastname: He
authors.affiliation: Department of Botany and Microbiology, Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA.
authors.forename: Ye
authors.initials: Y
authors.lastname: Deng
authors.affiliation: 1] State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China [2] Department of Botany and Microbiology, Institute for Environmental Genomics, University of Oklahoma, Norman, OK, USA [3] Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
authors.forename: Jizhong
authors.initials: J
authors.lastname: Zhou
mesh_terms: D000531:Altitude; D001419:Bacteria / Q000235:genetics* / Q000378:metabolism; D017753:Ecosystem; D064351:Genes, Microbial / Q000235:genetics*; D014644:Genetic Variation; D054892:Metagenome; D056186:Metagenomics; D006109:Poaceae / Q000382:microbiology; D012988:Soil Microbiology; D018609:Tibet