Changes in Alpine Soil Bacterial Communities With Altitude and Slopes at Mount Shergyla, Tibetan Plateau: Diversity, Structure, and Influencing Factors

Abstract

The alpine ecosystem as one of the most representative terrestrial ecosystems has been highly concerned due to its susceptibility to anthropogenic impacts and climatic changes. However, the distribution pattern of alpine soil bacterial communities and related deterministic factors still remain to be explored. In this study, soils were collected from different altitudes and slope aspects of the Mount (Mt.) Shergyla, Tibetan Plateau, and were analyzed using 16S rRNA gene-based bioinformatics approaches. Acidobacteriota and Proteobacteria were identified consistently as the two predominant phyla in all soil samples, accounting for approximately 74% of the bacterial community. The alpha diversity of the soil bacterial community generally increased as the vegetation changed with the elevated altitude, but no significant differences in alpha diversity were observed between the two slopes. Beta diversity analysis of bacterial community showed that soil samples from the north slope were always differentiated obviously from the paired samples at the south slope with the same altitude. The whole network constituted by soil bacterial genera at the Mt. Shergyla was parsed into eight modules, and Elev-16S-573, Sericytochromatia, KD4-96, TK10, Pedomicrobium, and IMCC26256 genera were identified as the “hubs” in the largest module. The distance-based redundancy analysis (db-RDA) demonstrated that variations in soil bacterial community thereof with the altitude and slope aspects at the Mt. Shergyla were closely associated with environmental variables such as soil pH, soil water content, metal concentrations, etc. Our results suggest that environmental variables could serve as the deterministic factors for shaping the spatial pattern of soil bacterial community in the alpine ecosystems.

Whole-Genome Sequencing and Metagenomics Reveals Diversity and Prevalence of Soil Listeria spp. in the Nantahala National Forest

“…3B). The shift of bacterial community composition with elevation has also been noted in other mountain regions and attributed to changes in soil physicochemical properties [71,72]. In future studies, conducting ecological network analysis of Listeria spp.…”

Association between Soil Physicochemical Properties and Bacterial Community Structure in Diverse Forest Ecosystems

“…In previous studies, vegetation, associated soil physicochemical properties, and stand age have been shown to influence bacterial community composition [70,72,81]. Additionally, we did not consider the effects of altitude on the soil bacterial community, despite the pronounced altitudinal patterns observed in soil bacterial communities [70,89,92,93]. Finally, the observed patterns are based on a single sampling event.…”

“…Previous studies suggest that soil bacterial community assembly is driven by a combination of deterministic and stochastic processes [8,46], but the relative importance of these two processes varies greatly depending on forest stand age [8], environmental factors [53,[85][86][87], plant diversity [8], SOC [85,88], soil pH [86,89], soil moisture [87,89], and soil fungi [90] as critical mediators. Numerous pieces of evidence support that the soil bacterial community is primarily dominated by stochastic processes [53,71,84,91].…”

Comparative Study of Soil Microbial Diversity on Different Slope Orientations in Karst Rocky Mountains of Guangxi, China

“…The dynamics, activity and ecology of soil microbial community are significantly affected by topography, temperature, soil moisture, and soil organic matter (Florinsky et al, 2004; Zou et al, 2022). Slope orientations, by altering the solar radiation received by the surface, can affect microclimates (e.g., soil temperature, evapotranspiration) (Florinsky et al, 2004; Bennie et al, 2008), soil properties (e.g., water retention, soil organic matter) (Yimer et al, 2006; Geroy et al, 2011), and hydrological processes (Broxton et al, 2009).…”