Soil microbial‐mediated sulfur cycle and ecological network under typical desert halophyte shrubs

Abstract

The sulfur (S) cycle is one of the geochemical element cycles in which microorganisms play a key driving role. The microbial function of soil S cycling in response to desert degradation, however, remains largely unknown. We used metagenomics to analyze the characteristics of microbial communities and their functional genes involved in the S cycles under natural water gradients with three typical halophytes shrubs in the Ebinur Lake basin Desert, China. Our results showed that the rhizosphere effect, water gradient, and halophyte type played a major role in shaping the S cycle. On the whole, in the rhizosphere type and low water environment, the functional genes involved in the S cycle had high abundance, and the sulfur oxidizing protein (SOX) system in Alhagi sparsifolia had a high expression level. In the S cycle network structure, as the soil water content decreased, the complexity in S gene networks increased, showing the characteristics of clustering and high connectivity. Indicates the strengthening mode in microbial interactions with the water content. Interestingly, the negative correlation of the network changed with the water content, and there was more competition among communities under the low water gradient and more cooperation under the high water gradient. Through the correlation between environmental factors and the network, nitrate (NO 3 À ) and soil available S (AS) constrained most S gene ecology networks. The key species involved in the S cycle were halophilic microorganisms. These results can enhance the understanding of soil S biogeochemical processes and contribute to the mitigation of desertification by improving soil conservation.

Salinity affects microbial function genes related to nutrient cycling in arid regions

“… Diagram depicting the sulfur cycling processes. The middle sulfur cycling diagram is reprinted with permission from Li et al (2022) , licensed under John Wiley & Sons. *, **, and *** indicate significant differences in functional genes between hypersaline and saline soils at FDR < 0.05, FDR < 0.01, and FDR < 0.001, respectively.…”

Drivers of rhizosphere microbial differences in desert genus Haloxylon

“…Microbial community ecology has evolved from initially describing microbial communities to a mechanistic understanding of the underlying processes of community assembly (Ovaskainen et al, 2017). Combat between deterministic and stochastic processes influences the assembly of microbial communities (Li, Lv, & Hu, 2022). Emphasizing the contribution of different ecological processes to community assembly is the key to deepening our understanding of microbial ecology (Stegen et al, 2016).…”