Eutrophication causes microbial community homogenization via modulating generalist species

Mengdie Geng; Weizhen Zhang; Ting Hu; Rong Wang; Xiaoying Cheng; Jianjun Wang

doi:10.1016/j.watres.2021.118003

Eutrophication causes microbial community homogenization via modulating generalist species

Water Res. 2022 Feb 15:210:118003. doi: 10.1016/j.watres.2021.118003. Epub 2021 Dec 24.

Authors

Mengdie Geng¹, Weizhen Zhang², Ting Hu³, Rong Wang³, Xiaoying Cheng⁴, Jianjun Wang⁵

Affiliations

¹ School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Nanjing 210008, China.
² State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Nanjing 210008, China; Center for the Pan-third Pole Environment, Lanzhou University, Lanzhou 730000, China.
³ State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Nanjing 210008, China.
⁴ School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China. Electronic address: chengxiaoy@jiangnan.edu.cn.
⁵ State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: jjwang@niglas.ac.cn.

PMID: 34982976
DOI: 10.1016/j.watres.2021.118003

Abstract

Eutrophication substantially influences the community structure of aquatic organisms and has become a major threat to biodiversity. However, whether eutrophication is linked to homogenization of microbial communities and the possible underlying mechanisms are poorly understood. Here, we studied bacterial and fungal communities from water and sediments of 40 shallow lakes in the Yangtze-Huaihe River basin, a representative area characterized by intensifying eutrophication in China, and further examined the beta diversity patterns and underlying mechanisms under eutrophication conditions. Our results indicate that eutrophication generally caused biotic homogenization of bacterial and fungal communities in both habitats showing decreased community variations for the sites with a higher trophic state index (TSI). In the two habitats, community dissimilarities were positively correlated with TSI changes for both taxonomic groups, while the local contribution to beta diversity (LCBD) remarkably declined with increasing TSI for the fungal community. These phenomena were consistent with the pivotal importance of the TSI in statistically accounting for beta diversity of bacterial and fungal communities in both habitats. In addition, we found that physicochemical factors such as water temperature and pH were also important for bacterial and fungal communities in water, while heavy metal elements were important for the communities in sediments. Interestingly, generalist species, rather than specialist species, were revealed to more dominantly affect the variations in beta diversity along the trophic gradient, which were quantified by Bray-Curtis dissimilarity and LCBD. Collectively, our findings reveal the importance of generalist species in contributing to the change of beta diversity of microbial communities along trophic gradients, which have profound implications for a comprehensive understanding of the effects of eutrophication on microbial community.

Keywords: Beta diversity; Biotic homogenization; Eutrophication; Generalist species; Local contributions to beta diversity (LCBD).

MeSH terms

Bacteria / genetics
Biodiversity
Eutrophication*
Lakes
Microbiota*