Soil CO2 and N2O emissions and microbial abundances altered by temperature rise and nitrogen addition in active-layer soils of permafrost peatland

作者：Yanyu Song, Xiaofeng Cheng, Changchun Song, Mengting Li, Siqi Gao, Zhendi Liu, Jinli Gao, Xianwei Wang · 发表于：Frontiers in Microbiology · 年份：2022 · DOI：10.3389/fmicb.2022.1093487 · 被引用次数：33 · 研究领域：Peatlands and Wetlands Ecology、Climate change and permafrost、Soil Carbon and Nitrogen Dynamics

Changes in soil CO 2 and N 2 O emissions due to climate change and nitrogen input will result in increased levels of atmospheric CO 2 and N 2 O, thereby feeding back into Earth’s climate. Understanding the responses of soil carbon and nitrogen emissions mediated by microbe from permafrost peatland to temperature rising is important for modeling the regional carbon and nitrogen balance. This study conducted a laboratory incubation experiment at 15 and 20°C to observe the impact of increasing temperature on soil CO 2 and N 2 O emissions and soil microbial abundances in permafrost peatland. An NH 4 NO 3 solution was added to soil at a concentration of 50 mg N kg −1 to investigate the effect of nitrogen addition. The results indicated that elevated temperature, available nitrogen, and their combined effects significantly increased CO 2 and N 2 O emissions in permafrost peatland. However, the temperature sensitivities of soil CO 2 and N 2 O emissions were not affected by nitrogen addition. Warming significantly increased the abundances of methanogens, methanotrophs, and nir K-type denitrifiers, and the contents of soil dissolved organic carbon (DOC) and ammonia nitrogen, whereas nir S-type denitrifiers, β-1,4-glucosidase (βG), cellobiohydrolase (CBH), and acid phosphatase (AP) activities significantly decreased. Nitrogen addition significantly increased soil nir S-type denitrifiers abundances, β-1,4-N- acetylglucosaminidase (NAG) activities, and ammonia nitrogen and nitrate nitrog...