文献类型：期刊文献

英文题名：Effects of long-term increased N deposition on tropical montane forest soil N2 and N2O emissions

作者：Tang, Wenguang[1,2] Chen, Dexiang[1] Phillips, Oliver L.[3] Liu, Xian[4] Zhou, Zhang[1] Li, Yide[1] Xi, Dan[4] Zhu, Feifei[2,7] Fang, Jingyun[5] Zhang, Limei[6] Lin, Mingxian[1] Wu, Jianhui[1] Fang, Yunting[2,7]

第一作者：Tang, Wenguang

通信作者：Fang, Yunting

机构：[1] Jianfengling National Key Field Observation and Research Station for Forest Ecosystem, Research Institute of Tropical Forestry, Chinese Academy of Forestry, Guangzhou, 510520, China; [2] CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, China; [3] School of Geography, University of Leeds, Leeds, LS2 9JT, United Kingdom; [4] College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, 350002, China; [5] Department of Ecology, College of Urban and Environmental Sciences, Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, 100871, China; [6] State Key Laboratory of Urban and Regional Ecology, Research Centre for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; [7] Qingyuan Forest CERN, The Chinese Academy of Sciences, Shenyang, Liaoning, 110014, China

年份：2018

卷号：126

起止页码：194-203

外文期刊名：Soil Biology and Biochemistry

收录：EI(收录号：20183905868760);Scopus(收录号：2-s2.0-85053803739)

语种：英文

外文关键词：Denitrification - Soils - Greenhouse gases - Nitrogen oxides - Forestry - Gas emissions - Tropics

摘要：Nitrogen (N) deposition is projected to substantially increase in the tropics over the coming decades, which is expected to lead to enhanced N saturation and gaseous N emissions from tropical forests (via NO, N2O, and N2). However, it is unclear how N deposition in tropical forests influences both the magnitude of gaseous loss of nitrogen and its partitioning into the N2 and N2O loss mechanisms. Here, for the first time, we employed the acetylene inhibition technique and the 15N-nitrate labeling method to quantify N2 and N2O emission rates for long-term experimentally N-enriched treatments in primary and secondary tropical montane forest. We found that during laboratory incubation under aerobic conditions long-term increased N addition of up to 100 kg N ha?1 yr?1 at Jianfengling forest, China, did not cause a significant increase in either N2O or N2 emissions, or N2O/N2. However, under anaerobic conditions, N2O emissions decreased and N2 emissions increased with increasing N addition in the secondary forest. These changes may be attributed to substantially greater N2O reduction to N2 during denitrification, further supported by the decreased N2O/N2 ratio with increasing N addition. No such effects were observed in the primary forest. In both forests, N addition decreased the contribution of denitrification while increasing the contribution of co-denitrification and heterotrophic nitrification to N2O production. Denitrification was the predominant pathway to N2 production (98–100%) and its contribution was unaffected by N addition. Despite the changes in the contributions of denitrification to N2O gas emissions, we detected no change in the abundance of genes associated with denitrification. While the mechanisms for these different responses are not yet clear, our results indicate that the effects of N deposition on gaseous N loss were ecosystem-specific in tropical forests and that the microbial processes responsible for the production of N gases are sensitive to N inputs. ? 2018