盐渍化对许多地区的农业和环境构成严重威胁,柴达木盆地也是如此,青海省,中国西北部。微生物对调节生态系统的生化循环具有重要影响;然而,探索微生物多样性和与盐渍土生态系统的相互作用的系统研究仍然很少。因此,本文进行了16SrRNA高通量测序,以表征不同盐渍化水平土壤下的微生物多样性:非盐渍化(NS,2.25g/L),中度盐化(MS,6.14g/L)和高度盐化(HS,9.82g/L)。α多样性结果表明,HS土壤与NS和MS土壤差异显著。相似性分析(ANOSIM)和主坐标分析(PCoA)表明NS和MS紧密聚集,而HS与其他两个分离。在分类学水平上观察到微生物组成的显着差异。在研究的土壤中,变形杆菌(42.29-79.23%)是最丰富的门。在MS和HS土壤中,γ变形杆菌(52.49和66.61%)的丰度较高。在HS土壤中,甲虫和假单胞菌是主要细菌;在MS土壤中,固氮菌和甲基杆菌含量很高。通过线性判别分析(LDA)效应大小(LEfSe)分析检测到大多数属于变形杆菌和放线菌的属,这表明具有降解有机物和完成营养循环能力的微生物可以很好地适应盐条件。进一步分析(冗余分析和Mantel检验)表明微生物群落主要与土壤盐分有关,电导率(EC1:5),总磷(TP)和氨氮(NH4+-N)。总的来说,这项研究的结果可以为更好地理解柴达木盆地不同盐渍土壤中的优势土著微生物及其在生化循环中的作用提供见解,青海省,中国。有关典型杨树种下微生物群落的研究应进一步阐明植物-微生物相互作用的机理和微生物在盐渍土壤修复中的应用效益。
Salinization is a severe threat to agriculture and the environment in many areas, and the same in Qaidam Basin, Qinghai Province, Northwestern China. Microorganisms have an important influence on regulating the biochemical cycles of ecosystems; however, systematic research exploring microbial diversity and interactions with saline-soil ecosystems\' environmental variables remains scarce. Thus, 16 S rRNA high-throughput sequencing was performed in this paper to characterize microbial diversity under different levels of salinized soils: non-salinized (NS, 2.25 g/L), moderately salinized (MS, 6.14 g/L) and highly salinized (HS, 9.82 g/L). The alpha diversity results showed that the HS soil was significantly different from the NS and MS soils. An analysis of similarity (ANOSIM) and a principal co-ordinates analysis (PCoA) indicated that NS and MS clustered closely while HS separated from the other two. Significant differences in microbial composition were observed at the taxonomic level. Proteobacteria (42.29-79.23 %) were the most abundant phyla in the studied soils. Gammaproteobacteria (52.49 and 66.61 %) had higher abundance in the MS and HS soils at the class level; Methylophaga and Pseudomonas were the predominant bacteria in the HS soil; and Azotobacter and Methylobacillus were abundant in the MS soil. Most genera belonging to Proteobacteria and Actinobacteria were detected via a linear discriminate analysis (LDA) effect size (LEfSe) analysis, which indicated that microbes with the ability to degrade organic matter and accomplish nutrient cycling can be well-adapted to salt conditions. Further analyses (redundancy analysis and Mantel test) showed that the microbial communities were mainly related to the soil salinity, electrical conductivity (EC1:5), total phosphorus (TP) and ammonia nitrogen (NH4+-N). Overall, the findings of the study can provide insights for better understanding the dominant indigenous microbes and their roles in biochemical cycles in different saline soils in the Qaidam Basin, Qinghai Province, China. The researches related to microbial community under typical poplar species should further clarify the mechanism of plant-microbial interaction and benefit for microbial utilization in salt soil remediation.