Effect of soil archaea on N2O emission in alpine permafrost

Soil microbial communities are pivotal in permafrost biogeochemical cycles, yet the variations of abundant and rare microbial taxa and their impacts on greenhouse gas emissions in different seasons, remain elusive, especially in the case of soil archaea. Here, we conducted a study on soil abundant and rare archaeal taxa during the growing and non-growing seasons in the active layer of alpine permafrost in the Qinghai-Tibetan Plateau. The results suggested that, for the archaeal communities in the sub-layer, abundant taxa exhibited higher diversity, while rare taxa maintained a more stable composition from the growing to non-growing season. Water soluble organic carbon and soil porosity were the most significant environmental variables affecting the compositions of abundant and rare taxa, respectively. Stochastic and deterministic processes dominated the assemblies of rare and abundant taxa, respectively. The archaeal ecological network influenced N₂O flux through different modules. Rare taxa performed an essential role in stabilizing the network and exerting important effects on N₂O flux. Our study provides a pioneering and comprehensive investigation aimed at unravelling the mechanisms by which archaea or other microorganisms influence greenhouse gas emissions in the alpine permafrost.