随着全球气候变化与人类不合理利用之间的相互作用,青藏高原的高山草甸遭受了不同程度的风化。通过了解草甸退化过程中土壤微生物区系的多样性,可以促进发现退化机制和恢复策略。因此,我们使用Illumina测序技术来研究土壤微生物多样性的模式,微生物群落组成,以及所有非降解(ND)中微生物变化的驱动因素,轻度降级(LD),中度降解(MD),青藏高原东南部的高山草甸和严重退化(SD)。我们的研究结果指出,随着退化的加剧,植被特征显著降低,所有退化草甸的土壤参数差异显著。土壤有机碳(SOC)含量,总氮(TN),有效磷(AN),土壤总磷(AK)随着降解的增加而减少。无论草甸降解水平如何,优势细菌门都是相同的,其中放线菌(37.67%)和变形菌(20.62%)具有最高的相对丰度。同时,优势真菌为子囊菌(49.9%)。基于线性判别分析(LDA)和效应大小(LEfSe)方法,在退化的高山草甸中发现了38种细菌和49种真菌,其中大部分属于放线菌和子囊菌,分别。Mantel试验分析表明,细菌群落主要依赖于地下生物量,pH值,土壤有机碳,和总氮,虽然真菌群落显著依赖于土壤有机碳,总氮,可用氮气,和可用的钾。这些结果表明,高寒草甸的退化有助于青藏高原微生物多样性和组成的变化。然而,这种影响主要取决于土壤因素。
With the interaction between global climate change and unreasonable human utilization, the alpine meadows on the Qinghai-Tibet Plateau have suffered various weathering degrees. Uncovering the degradation mechanism and restoration strategies can be facilitated by gaining insights into the diversity of soil microflora during meadow degradation. Therefore, we used Illumina sequencing technology to investigate the patterns of soil microbial diversity, microbial community composition, and the driving factors of microbial change in all non-degraded (ND), lightly degraded (LD), moderately degraded (MD), and severely degraded (SD) alpine meadows in the southeastern Qinghai-Tibet Plateau. Our results pointed out that with the intensification of degradation, vegetation characteristics were significantly reduced, and soil parameters significantly varied among all degraded meadows. The contents of soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AN), and total phosphorous (AK) in soils decreased with the increase of degradation. The dominant bacterial phyla were the same regardless of the meadow degradation level with Actinobacteria (37.67%) and Proteobacteria (20.62%) having the highest relative abundance. Meanwhile, the dominant fungi were Ascomycota (49.9%). Based on the linear discriminant analysis (LDA) and effect size (LEfSe) method, 38 bacterial and 49 fungal species were found to be affected in the degraded alpine meadow, most of which belonged to Actinobacteria and Ascomycota, respectively. Mantel test analysis illustrated that the bacterial community was mainly significantly dependent on below-ground biomass, pH, soil organic carbon, and total nitrogen, while the fungal community was significantly dependent on soil organic carbon, total nitrogen, available nitrogen, and available potassium. These results suggest that the degeneration of alpine meadows contributes to the variability of the diversity and composition of microflora on the Tibetan plateau. Yet this effect is mainly dependent on soil factors.