Diversity and Variation of Asymbiotic Nitrogen-Fixing Microorganisms in Alpine Grasslands on the Tibetan Plateau

Frontiers in Ecology and Evolution

A. Allan Degen¹  Zhanhuan Shang²  Fei Li⁴  Lingyan Qi⁴  Yanfu Bai⁴  Lin Ma⁴  Zhen Peng⁴  Wenyin Wang⁴  Jin Han⁴  Xiaochun Wang⁴  Tao Zhang⁴  Wenyan Li⁴  Haijun Zeng⁴  Mei Huang⁴ 

[1] Desert Animal Adaptations and Husbandry, Wyler Department of Dryland Agriculture, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Beersheba, Israel;Qinghai Provincial Key Laboratory of Adaptive Management on Alpine Grassland, Qinghai Academy of Animal and Veterinary Sciences, Qinghai University, Xining, China;Qinghai Provincial Key Laboratory of Restoration Ecology of Cold Areas, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, China;State Key Laboratory of Grassland Agro-Ecosystems, School of Life Sciences, Lanzhou University, Lanzhou, China;

关键词: asymbiotic nitrogen-fixing bacteria;    alpine grassland;    Tibetan Plateau;    diversity;    community structure;   

DOI  :  10.3389/fevo.2021.702848

来源: DOAJ

【 摘 要 】

Asymbiotic nitrogen-fixing (ANF) bacteria contribute a substantial amount of nitrogen in ecosystems, especially in those with low symbiotic nitrogen fixation (SNF) capability. Degradation of alpine grassland is widespread on the Tibetan Plateau and sown grassland has become one of the main strategies for grassland restoration. However, the diversity and community structure of ANF bacteria in different grassland types remain unknown. The aim of this study was to fill this gap. Soil samples were obtained from 39 grassland plots selected from three counties in the eastern Tibetan Plateau. The plots were classified as natural grassland (NG), sown grassland (SG), lightly degraded grassland (LDG), and severely degraded grassland (SDG). ANF microbial communities of the four grassland types were compared at the level of community and species diversity by 16S rRNA high-throughput sequencing technology. The phylum Proteobacteria accounted for >72% of the ANF bacteria. The community structures of soil ANF bacteria differed significantly (p < 0.01) among grassland types. We concluded that: (1) planting gramineous forage could possibly mitigate the decrease in diversity of soil ANF bacteria caused by grassland degradation; and (2) the diversity of soil ANF bacteria in alpine grassland of the Tibetan Plateau is closely related to grassland degradation and restoration.

【 授权许可】

Unknown