文献类型：期刊文献

英文题名：Soil acid cations induced reduction in soil respiration under nitrogen enrichment and soil acidification

作者：Li, Yong[1,2] Sun, Jian[1] Tian, Dashuan[1] Wang, Jinsong[1] Ha, Denglong[3] Qu, Yuxi[3] Jing, Guangwei[3] Niu, Shuli[1,4]

第一作者：李勇;Li, Yong

通信作者：Niu, SL[1]

机构：[1]Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, Key Lab Ecosyst Network Observat & Modeling, Beijing 100101, Peoples R China;[2]Chinese Acad Forestry, Inst Wetland Res, Beijing Key Lab Wetland Serv & Restorat, Beijing 100091, Peoples R China;[3]Jigongshan Nat Reserve, Xinyang 464000, Peoples R China;[4]Univ Chinese Acad Sci, Dept Resources & Environm, Beijing 100049, Peoples R China

年份：2018

卷号：615

起止页码：1535-1546

外文期刊名：SCIENCE OF THE TOTAL ENVIRONMENT

收录：;EI(收录号：20173804183894);Scopus(收录号：2-s2.0-85029538208);WOS:【SCI-EXPANDED(收录号:WOS:000414922600157)】；

基金：The authors would like to thank Wei Zhang, Mengjun Hu and Yanchun Liu for their help in the field station. This study was financially supported by National Natural Science Foundation of China (41403073, 31625006) and the Thousand Young Talents program to S. Niu.

语种：英文

外文关键词：Autotrophic respiration; Heterotrophic respiration; Nitrogen deposition; Soil acidification; Microbial community composition; Cellulose degrading enzymes

摘要：Atmospheric nitrogen (N) deposition and soil acidification both can largely change soil microbial activity and root growth with a consequent impact on soil respiration (R-s). However, it remains unclear which one, N enrichment or soil acidification, plays more important role in impacting soil respiration. We conducted a manipulative experiment to simulate N enrichment (10 gm(-2) yr(-1) NH4NO3) and soil acidity (0.552mol H+ m(-2) yr(-1) sulfuric acid) and compared their effects on R-s and its components in a subtropical forest. The results showed that soil pH was reduced by 0.4 similarly under N addition or acid addition after 3 years' treatment. Acid addition decreased autotrophic respiration (R-a) by 22-35% and heterotrophic respiration (R-h) by 22-23%, resulting in a reduction of R-s by 22-26% in the two years. N addition reduced R-a, R-h, R-s less than acid addition did. The reductions of R-s and its components were attributed to increase of soil acid cations and reduction of cellulose degrading enzymes activity. N addition and soil acidification significantly enhanced fungal to bacterial ratio. All the cellulose degrading enzymes were reduced more by soil acidity (43-50%) than N addition (30-39%). The principal component scores of degrading enzymes activity showed significantly positive relationships with R-h. Structural equation model showed that soil acidification played more important role than N enrichment in changing R-s and its components. We therefore suggest that soil acidification is an important mechanism underlying soil respiration changes, and should be incorporated into biogeochemical models to improve the prediction of ecosystem C cycling in the future scenarios of anthropogenic N deposition and acid enrichment. (C) 2017 Elsevier B.V. All rights reserved.