Diversity of prokaryotic microorganisms in alkaline saline soil of the Qarhan Salt Lake area in the Qinghai–Tibet Plateau

Abstract

The composition of microbial communities varies considerably across ecological environments, particularly in extreme environments, where unique microorganisms are typically used as the indicators of environmental conditions. However, the ecological reasons for the differences in microbial communities remain largely unknown. Herein, we analyzed taxonomic and functional community profiles via high-throughput sequencing to determine the alkaline saline soil bacterial and archaeal communities in the Qarhan Salt Lake area in the Qinghai–Tibet Plateau. The results showed that Betaproteobacteria (Proteobacteria) and Halobacteria (Euryarchaeota) were the most abundant in the soils of this area, which are common in high salinity environments. Accordingly, microbes that can adapt to local extremes typically have unique metabolic pathways and functions, such as chemoheterotrophy, aerobic chemoheterotrophy, nitrogen fixation, ureolysis, nitrate reduction, fermentation, dark hydrogen oxidation, and methanogenesis. Methanogenesis pathways include hydrogenotrophic methanogenesis, CO2 reduction with H2, and formate methanogenesis. Thus, prokaryotic microorganisms in high salinity environments are indispensable in nitrogen and carbon cycling via particular metabolic pathways.

Soil Microbial Stress Responses under External Chemical and Physical Environmental Stresses

“…The effects of salinization on plants are mainly ion toxicity and osmotic persecution [107] . In the high salt environment, the dominant phylum in the bacterial community is proteus, followed by Bacteroides , Firmicutes and Actinomycetes [108] . It is essential for prokaryotic microorganisms in a high salinity environment to participate in the nitrogen and carbon cycle through specific metabolic pathways.…”

Taxonomic diversity and functional potential of microbial communities in salt lakes Gudzhirganskoe and Nukhe-Nur (Barguzin depression, Baikal Rift Zone)

“…We ob-tained sequences whose closest homologues belonged to the bacteria Wenzhouxiangella, Methylonatrum, Alcanivorax, Nitrincola, Anoxynatronum, Spirochaeta. This group of bacteria was assigned to moderate halophiles (Zhilina et al, 1996;Wang et al, 2022;Borsodi et al, 2017;Liao et al, 2020). In winter, alkaliphilic bacteria were presented by the genus Roseinatronobacter (рН opt > 9.5) (Sorokin et al, 2000).…”

Development of Microbial Indicators in Ecological Systems

“…Liu et al investigated soil microbial community diversity and richness from eight distinct landscapes on the Loess Plateau, representing forests, grassland, and agricultural lands at the position of 107°39′–109°36′ and the altitude of 415–1633 m. They found that soil fungal diversity and richness were different among samplings, which indicates that the fungal community structure can be used as a bioindicator in the Loess Plateau region [ 58 ]. In the Qarhan salt lake area of the Qinghai-Tibet Plateau, Proteobacteria and Halobacteria were dominant in soil, indicating that they can be used as bioindicators to assess the Qarhan salt lake area [ 59 ].…”