文献类型：期刊文献

英文题名：The Driving Effects of Nitrogen Deposition on Nitrous Oxide and Associated Gene Abundances at Two Water Table Levels in an Alpine Peatland

作者：Zhang, Wantong[1,2,4] Tao, Xiuping[2] Hu, Zhengyi[4] Kang, Enze[1] Yan, Zhongqing[1,3] Zhang, Xiaodong[1,3] Wang, Jinzhi[1,3]

第一作者：Zhang, Wantong

机构：[1] Institute of Wetland Research, Chinese Academy of Forestry, Beijing Key Laboratory of Wetland Services and Restoration, Beijing, 100091, China; [2] Insititute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, 610218, China; [3] Sichuan Zoige Wetland Ecosystem Research Station, Tibetan Autonomous Prefecture of Aba, 624500, China; [4] Sino-Danish Centre for Education and Research, University of Chinese Academy of Sciences, Beijing, 100049, China

年份：2022

外文期刊名：SSRN

收录：EI(收录号：20220469956)

语种：英文

外文关键词：Climate change - Denitrification - Groundwater - Nitrification - Nitrogen oxides - Soils - Wetlands

摘要：Alpine peatlands are recognized as a weak or negligible source of nitrous oxide (N2O). Anthropogenic activities and climate change resulted in the altered water table (WT) levels and increased nitrogen (N) deposition, which could potentially transition this habitat into a N2O emission hotspot. However, the underlying mechanism related with the effects is still uncertain. Hence, we conducted a mesocosm experiment to address the response of growing-season N2O emissions and the gene abundances of nitrification (bacterial amoA) and denitrification (narG, nirS, norB and nosZ) to the increased N deposition (20 kg N ha-1 yr-1) at two WT levels (WT-30, 30 cm below soil surface; WT10, 10 cm above soil surface) in the Zoige alpine peatland, Qinghai-Tibetan Plateau. The results showed that the WT did not affect N2O emissons, and this was attributed with the limitation of soil NO3-. The higher WT level increased denitrification (narG and nirS gene abundance) resulting in the depletion of soil NO3-, but the consequent NO3- deficiency further limited denitrificaition, while the WT did not affect nitrification (bacterial amoA gene abundance). Meanwhile, the N deposition increased N2O emissions, regardless of WT levels. This was associated with the N-deposition induced increase in denitrification-related gene abundances of narG, nirS, norB and nosZ at WT-30 and narG at WT10. Additionally, the N2O emission factor assigned to N deposition was 1.3% at WT-30 and 0.9% at WT10, respectively. Our study provided comprehensive understanding of the mechanisms referring N2O emissions in response to the interactions between climate change and human disturbance from this high-altitude peatland. ? 2022, The Authors. All rights reserved.