Salinity shapes microbial diversity and community structure in surface sediments of the Qinghai-Tibetan Lakes

Abstract

Investigating microbial response to environmental variables is of great importance for understanding of microbial acclimatization and evolution in natural environments. However, little is known about how microbial communities responded to environmental factors (e.g. salinity, geographic distance) in lake surface sediments of the Qinghai-Tibetan Plateau (QTP). In this study, microbial diversity and community structure in the surface sediments of nine lakes on the QTP were investigated by using the Illumina Miseq sequencing technique and the resulting microbial data were statistically analyzed in combination with environmental variables. The results showed total microbial community of the studied lakes was significantly correlated (r = 0.631, P < 0.001) with lake salinity instead of geographic distance. This suggests that lake salinity is more important than geographic distance in shaping the microbial diversity and community structure in the studied samples. In addition, the abundant and rare taxa (OTUs with relative abundance higher than 1% and lower than 0.01% within one sample, respectively) were significantly (P < 0.05) correlated (r = 0.427 and 0.783, respectively) with salinity, suggesting rare taxa might be more sensitive to salinity than their abundant counterparts, thus cautions should be taken in future when evaluating microbial response (abundant vs. rare sub-communities) to environmental conditions.

Microbial community composition in alpine lake sediments from the Hengduan Mountains

“…Proteobacteria (22.27%–64.48%) was the dominant phylum in all sediments, followed by Bacteroidetes (4.40%–30.85%), Acidobacteria (2.47%–12.32%), Chloroflexi (1.13%–9.82%), and Planctomycetes (0.87%–12.78%), which accounted for a large proportion of the phyla in most sampling stations. This result is similar to the results of microbial diversity studies in surface sediments of Qinghai Lake, Tibet (Yang, Ma, Jiang, Wu, & Dong, ). At the class level, Betaproteobacteria , Deltaproteobacteria , Gammaproteobacteria , Acidobacteria , Alphaproteobacteria, and Sphingobacteria were dominant, and appeared in almost all samples Appendix Figure ).…”

A glimpse of the prokaryotic diversity of the Large Aral Sea reveals novel extremophilic bacterial and archaeal groups

“…Hypersaline lakes offer a unique environment for microbial life and are considered as hot spots of microbial diversity (Ley et al, ; Oren, ). Microbes are fundamental components of hypersaline aquatic ecosystems and play essential roles in global biogeochemical cycles (Sorokin et al, ; Yang, Ma, Jiang, Wu, & Dong, ).…”

Analysis of microbial communities in natural halite springs reveals a domain‐dependent relationship of species diversity to osmotic stress

“…However, only a few studies have investigated the effect of salinity on microbial alpha diversity, with conflicting results: either no correlation (Casamayor et al ., ; Joint et al ., ; Wang et al ., ) or mixed results depending on the diversity index used (Benlloch et al ., ; Dillon et al ., ; Campbell and Kirchman, ). The most convincing study to date used Illumina sequencing of 16S rRNA genes to demonstrate significantly declining diversity with salinity (Yang et al ., ) based on a sample set of nine lakes.…”