Hydrochemistry Predominantly Shapes the Unique Nitrogen-Fixing Bacterial Communities in Tibetan Hot Springs  

作　　者：Zhao-Qi Song Li Wang Yaru Ma Dandan Deng Yang Song Feng Liang Xiangyu Guan Wen-Jun Li Hongchen Jiang 

机构地区：[1]Engineering Technology Research Center of Biomass Degradation and Gasification,College of Biology and Food,Shangqiu Normal University,Shangqiu 476000,China [2]School of Ocean Sciences,China University of Geosciences,Beijing 100083,China [3]State Key Laboratory of Biocontrol,Guangdong Key Laboratory of Plant Resources,School of Life Sciences,Sun Yat-sen University,Guangzhou 510275,China [4]State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430074,China

出　　处：《Journal of Earth Science》2025年第1期134-145,共12页地球科学学刊(英文版)

基　　金：supported by the National Natural Science Foundation of China(Nos.31300430,42172339,91951205);Key Scientific Research Project Plan of Colleges and Universities in Henan Province(No.18A180002);Science and Technology Research Project of Henan Province(No.152102310352)。

摘　　要：The Tibetan Plateau has a large number of hot springs with varying temperatures and hydrochemistry,high elevation,and limited nitrogenous nutrition.Nitrogen-fixing bacteria(NFB)can fix N_(2)to form ammonia and thus provide bioavailable nitrogen.However,there is limited knowledge about the distribution of NFB and its influencing factors in Tibetan hot springs.Here,we measured hydrochemical variables of the hot springs with a wide temperature range(32–77°C)in the Qucai and Daggyai geothermal zones on the Tibetan Plateau and investigated the composition of NFB using high-throughput sequencing of 16SrRNA and nif H genes.The Cl^(-)/SO_(4)^(2-)ratio in Qucai hot springs was higher than that in Daggyai,indicating that Qucai and Daggyai hot springs were more affected by the supply of liquid and gaseous phases,respectively.The NFB communities consisted predominantly of Nirtospirae,Chloroflexi,Deltaproteobacteria and an unidentified clade,with the last three acting as the main NFB with over 42%of the communities(the proportions are significantly larger than those found in hot springs of other geothermal regions).This demonstrates the uniqueness of NFB communities in Tibetan hot springs.NFB richness was limited by temperature in the studied Tibetan hot springs and was significantly lower than in low-elevation geothermal regions.The NFB community was predominantly affected by hydrochemistry,in contrast to the entire prokaryotic community,which was primarily influenced by temperature.This study expands our current understanding of NFB distribution and diversity as well as biogeochemical process in geothermal spring environments.

关 键 词：HYDROCHEMISTRY nitrogen-fixing bacteria nifH gene community structure Tibetan hot springs 

分 类 号：Q938[生物学—微生物学] P314.1[天文地球—固体地球物理学]