Sulfate reduction is an important biogeochemical process in the ecosphere; however, the major taxa of sulfate reducers have not been fully identified. Here, we used epicPCR (Emulsion, Paired Isolation, and Concatenation PCR) technology to identify the phylogeny of sulfate-reducing prokaryotes (SRP) in sediments from Tibetan Plateau saline lakes. A total of 12,519 OTUs and 883 SRP-OTUs were detected in ten lakes by sequencing of 16S rRNA gene PCR amplicons and epicPCR products of fused 16S rRNA plus dsrB gene, respectively, with Proteobacteria , Firmicutes, and Bacteroidetes being the dominant phyla in both datasets. The 120 highly abundant SRP-OTUs (> 1% in at least one sample) were affiliated with 17 described phyla, only 7 of which are widely recognized as SRP phyla. The majority of OTUs from both the whole microbial communities and the SRPs were not detected in more than one specific lake, suggesting high levels of endemism. The α-diversity of the entire microbial community and SRP sub-community showed significant positive correlations. The pH value and mean water temperature of the month prior to sampling were the environmental determinants for the whole microbial community, while the mean water temperature and total nitrogen were the major environmental drivers for the SRP sub-community. This study revealed there are still many undocumented SRP in Tibetan saline lakes, many of which could be endemic and adapted to specific environmental conditions. Electronic supplementary material The online version of this article (10.1186/s40168-019-0688-4) contains supplementary material, which is available to authorized users.

Degradation succession in forests is an important and serious land use/cover change problem in ecology, and during these processes soil microbial communities mediate the recycling of most important nutrients. To reveal the effect of degradation succession processes on soil microbial community diversity, structure, and species interrelationships, we collected abundant samples (21 per vegetation type) in broad-leaved forest, coniferous forest, and meadow to observe the microbial community dynamics. The results showed that diversity and structure of soil prokaryotic and fungal communities responded differently to different forest degradation processes, diversity of soil microbial communities increased during degradation processes. Soil microbial communities abundance changes may indicate that prokaryotic communities showed a living strategies change as an ecological adaption to harsh conditions during forest degradation process. While for fungal communities, their abundance changes may indicate that environmental selection pressure and plant selectivity during forest degradation process. Changes in soil prokaryotic communities and fungal communities were both correlated with soil carbon and nitrogen loss. The soil microbial interaction network analysis indicated more complex species interrelationships formed due to the loss of soil nutrients during degradation succession processes, suggesting soil microbial communities might form more complex and stable networks to resist the external disturbance of soil nutrient loss. All results suggested soil microorganisms, including bacteria, archaea and fungi, all involved in the soil nutrient decline during the forest degradation process.

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