Variation in Soil Microbial Communities Along an Elevational Gradient in Alpine Meadows of the Qilian Mountains, China

Abstract

Bacterial, archaeal, and eukaryota diversity in mountainous areas varies along elevational gradients, but details remain unclear. Here, we use a next-generation sequencing method based on 16S/18S rRNA to reveal the soil microbial diversity and community compositions of alpine meadow ecosystems along an elevation span of nearly 2,000 m (1,936–3,896 m) in China’s Qilian Mountains. Both bacterial and eukaryota diversity increased linearly with increasing elevation, whereas archaeal diversity increased, but not significantly. The diversity patterns of several phyla in the bacterial, archaeal, and eukaryota communities were consistent with the overall elevational trend, but some phyla did not follow this pattern. The soil microbial community compositions were shaped by the coupled effects of regional climate and local soil properties. Intradomain links were more important than interdomain links in the microbial network of the alpine meadows, and these links were mostly positive. The bacteria formed more connections than either archaea or eukaryota, but archaea may be more important than bacteria in building the soil microbial co-occurrence network in this region. Our results provide new visions on the formation and maintenance of soil microbial diversity along an elevational gradient and have implications for microbial responses to climate change in alpine ecosystems.

Shifts in Soil Microbial Community Composition, Function, and Co-occurrence Network of Phragmites australis in the Yellow River Delta

“…In the present study, we constructed intra- and inter-kingdom co-occurrence networks based on bacterial and fungal OTUs. The results showed that intra-kingdom interactions (bacteria, bacteria, fungi, and fungi) form more easily than inter-kingdom (bacteria–fungi) interactions, indicating that microorganisms were more susceptible to the influence of intra-kingdom microorganisms ( Duan et al, 2021 ). Moreover, considering that the positive correlations between microbes were determined by their positive ecological interactions, such as commensalism and mutualism, it is not surprising that most interactions were positive because the degradation of OM requires the cooperation of various microorganisms, especially recalcitrant OM containing cellulose, hemicellulose, and lignin ( Wang et al, 2016 ).…”

“…Soil microorganisms, the main decomposers of plant and animal residues, are important components of the ecosystem and play key roles in regulating biogeochemical processes, including carbon, nitrogen, and sulfur cycling ( Madsen, 2011 ). Soil microbial community diversity and composition are susceptible to variations in biotic and abiotic factors, including plant litter, soil physicochemical properties, and climatic factors ( Cavicchioli et al, 2019 ; Gołębiewski et al, 2019 ; Duan et al, 2021 ). In particular, soil is a direct medium for the life of soil microorganisms, and slight changes in its physicochemical properties will significantly affect the diversity and composition of soil microorganisms.…”

Distinct Elevational Patterns and Their Linkages of Soil Bacteria and Plant Community in An Alpine Meadow of the Qinghai–Tibetan Plateau

“…In the current study, plant and soil bacterial diversity had different elevation diversity patterns. Previous studies yielded different findings on microbial community patterns with increasing elevation: a monotonous decrease [ 23 ], or increase [ 44 ], or no trend [ 45 ], or a humpbacked trend [ 46 ]. These different elevation distribution patterns of soil microbes might be caused due to the large variety of different environmental conditions [ 15 ].…”

Data_Sheet_1.docx

“…In the present study, we constructed intraand inter-kingdom co-occurrence networks based on bacterial and fungal OTUs. The results showed that intra-kingdom interactions (bacteria, bacteria, fungi, and fungi) form more easily than inter-kingdom (bacteria-fungi) interactions, indicating that microorganisms were more susceptible to the influence of intra-kingdom microorganisms (Duan et al, 2021). Moreover, considering that the positive correlations between microbes were determined by their positive ecological interactions, such as commensalism and mutualism, it is not surprising that most interactions were positive because the degradation of OM requires the cooperation of various microorganisms, especially recalcitrant OM containing cellulose, hemicellulose, and lignin (Wang et al, 2016).…”

“…Moreover, considering that the positive correlations between microbes were determined by their positive ecological interactions, such as commensalism and mutualism, it is not surprising that most interactions were positive because the degradation of OM requires the cooperation of various microorganisms, especially recalcitrant OM containing cellulose, hemicellulose, and lignin (Wang et al, 2016). Recently, microbial co-occurrence networks that were more inclined toward intrakingdom symbiosis have been reported in a variety of habitats, such as the rhizosphere and mountainous areas (Duan et al, 2021;Qian et al, 2021).…”