Biodegradable dissolved organic carbon shapes bacterial community structures and co-occurrence patterns in large eutrophic Lake Taihu  

作　　者：Lei Zhou Yongqiang Zhou Xiangming Tang Yunlin Zhang Erik Jeppesen 

机构地区：[1]Taihu Laboratory for Lake Ecosystem Research,State Key Laboratory of Lake Science and Environment,Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences,Nanjing 210008,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Department of Bioscience,Aarhus University,Silkeborg 8600,Denmark [4]Sino-Danish Centre for Education and Research,Beijing 100049,China [5]Limnology Laboratory,Department of Biological Sciences and Centre for Ecosystem Research and Implementation,Middle East Technical University,Ankara 06800,Turkey [6]Institute of Marine Sciences,Middle East Technical University,Mersin,Turkey

出　　处：《Journal of Environmental Sciences》2021年第9期205-217,共13页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos.41930760, 41807362, and 41977322);the Provincial Natural Science Foundation of Jiangsu in China (No.BK20181104);the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (No.QYZDB-SSWDQC016);supported by WATEC (Centre for Water Technology, AU);the TüBITAK outstanding scientists program 2232 (project 118C250)。

摘　　要：Interactions between dissolved organic matter(DOM)and bacteria are central in the biogeochemical cycles of aquatic ecosystems;however,the relative importance of biodegradable dissolved organic carbon(BDOC)compared with other environmental variables in structuring the bacterial communities needs further investigation.Here,we investigated bacterial communities,chromophoric DOM(CDOM)characteristics and physico-chemical parameters as well as examined BDOC via bioassay incubations in large eutrophic Lake Taihu,China,to explore the importance of BDOC for shaping bacterial community structures and co-occurrence patterns.We found that the proportion of BDOC(%BDOC)correlated significantly and positively with the DOC concentration and the index of the contribution of recent produced autochthonous CDOM(BIX).%BDOC,further correlated positively with the relative abundance of the tryptophan-like component and negatively with CDOM aromaticity,indicating that autochthonous production of protein-like CDOM was an important source of BDOC.The richness of the bacterial communities correlated negatively with%BDOC,indicating an enhanced number of species in the refractory DOC environments.%BDOC was identified as a significant stronger factor than DOC in shaping bacterial community composition and the co-occurrence network,suggesting that substrate biodegradability is more significant than DOC quantity determining the bacterial communities in a eutrophic lake.Environmental factors explained a larger proportion of the variation in the conditionally rare and abundant subcommunity than for the abundant and the rare bacterial subcommunities.Our findings emphasize the importance of considering bacteria with different abundance patterns and DOC biodegradability when studying the interactions between DOM and bacteria in eutrophic lakes.

关 键 词：Biodegradable dissolved organic carbon Bacterial community Co-occurrence networks Chromophoric dissolved organic matter Habitat niche breadth 

分 类 号：X524[环境科学与工程—环境工程]