The microbial gene diversity along an elevation gradient of the Tibetan grassland

作者：Yunfeng Yang, Ying Gao, Shiping Wang, Depeng Xu, Hao Yu, Linwei Wu, Qiaoyan Lin, Yigang Hu, Xiangzhen Li, Zhili He, Ye Deng, Jizhong Z. Zhou · 发表于：The ISME Journal · 年份：2013 · DOI：10.1038/ismej.2013.146 · 被引用次数：303 · 研究领域：Microbial Community Ecology and Physiology、Polar Research and Ecology、Soil Carbon and Nitrogen Dynamics

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 s...