Metagenomic insights into soil microbial communities involved in carbon cycling along an elevation climosequences

Abstract

Summary Diversity and community composition of soil microorganisms along the elevation climosequences have been widely studied, while the microbial metabolic potential, particularly in regard to carbon (C) cycling, remains unclear. Here, a metagenomic analysis of C related genes along five elevations ranging from 767 to 4190 m at Mount Kilimanjaro was analysed to evaluate the microbial organic C transformation capacities in various ecosystems. The highest gene abundances for decomposition of moderate mineralizable compounds, i.e. carbohydrate esters, chitin and pectin were found at the mid‐elevations with hump‐shaped pattern, where the genes for decompositions of recalcitrant C (i.e. lignin) and easily mineralizable C (i.e. starch) showed the opposite trend (i.e. U‐shaped pattern), due to high soil pH and seasonality in both low and high elevations. Notably, the gene abundances for the decompositions of starch, carbohydrate esters, chitin and lignin had positive relationships with corresponding C compounds, indicating the consistent responses of microbial functional profiles and metabolites to elevation climosequences. Understanding of adaptation of microbial communities, potential function and metabolites to elevation climosequences and their influencing factors provided a new insight for the regulation of terrestrial C storage.

Embracing mountain microbiome and ecosystem functions under global change

“…recalcitrant carbon) but fewer simple resources (e.g. simple sugars) (Dai et al ., 2021), A‐strategists should outcompete other strategists by investing in extracellular enzyme machinery, and thus catalyse polymer decomposition, likely leading to declined microbial litter decomposition and soil carbon loss with increasing elevations. The complexity of microbial traits could also be quantitatively simplified by a newly developed framework into synthetic axes to define a low‐dimensional trait space and to cluster species based on their traits while identifying those species with unique combinations of traits (Mouillot et al ., 2021).…”

Metagenomic Insights into the Structure of Microbial Communities Involved in Nitrogen Cycling in Two Integrated Multitrophic Aquaculture (IMTA) Ponds

“…In this study, SCC showed significant increases in the glyoxylate and dicarboxylate metabolism and twocomponent systems in water relative to SC. Glycoxylate and dicarboxylate metabolism are typical C metabolic pathways, and two-component systems are essential for C metabolism [45]. The above results indicated that S. constricta may mainly cause a shift C cycling in the water of shrimp-crab ponds.…”

Soil bacterial community changes along elevation gradients in karst graben basin of Yunnan-Kweichow Plateau

“…Though alpha diversities (e. g. Shannon indexes) may be monotonically decreased with elevation increasing, the U-trend of beta diversity in our study was in accordance with previous studies ( Nottingham et al, 2018 ). These results suggested that though the dissimilarity of soil bacterial communities was affected by multiple environmental factors ( Dai et al, 2021 ), changeable conditions at low or high elevation area sustained higher biodiversity than that at long-term stability environment in middle elevation area ( Simpson, 1980 ). Moreover, if continuous samplings were obtained in karst graben basin of Yunnan-Kweichow Plateau, the real changing rules may be not U-trend.…”

“…Considering that environmental conditions determine soil bacterial compositions ( Xun et al, 2015 ), and the occurrence and functioning of soil bacteria depend on their niches ( Banerjee et al, 2018 ), soil bacterial abundances (e.g., Acidobacteria, Actinobacteria, Proteobacteria, Verrucomicrobia, Firmicutes, Chloroflexi, Gemmatimonadetes, Bacteroidetes, Planctomycetes, Nitrospirae, and Latescibacteria) can follow hump-shaped, decreasing, increasing or U-shaped patterns along altitudinal gradients. These bacteria followed the above patterns due to them at their own optimum conditions though the responses of their ecological lifestyles to altitudinal gradients remain unclear ( Nottingham et al, 2018 ; Dai et al, 2021 ). Besides that, the different distribution patterns of bacteria taxa in two layers may be due to their response depending on soil depth ( Barbour et al, 2022 ).…”