DOI: 10.1029/2018JG004530
Scopus记录号: 2-s2.0-85052640584
论文题名: Ecosystem Carbon Use Efficiency Is Insensitive to Nitrogen Addition in an Alpine Meadow
作者: Ma F. ; Song B. ; Zhang F. ; Quan Q. ; Zhou Q. ; Niu S.
刊名: Journal of Geophysical Research: Biogeosciences
ISSN: 21698953
出版年: 2018
卷: 123, 期: 8 起始页码: 2388
结束页码: 2398
语种: 英语
英文关键词: alpine meadow
; carbon cycle
; carbon use efficiency
; coupling relation
; N availability
英文摘要: Carbon use efficiency (CUE) is an important variable in carbon cycling and a key parameter in biogeochemical models, which is expected to increase with N availability. However, how CUE changes with N input rate remains elusive and lacks field evidence. We implemented a field manipulative experiment to examine effects of N addition with six levels of rate (0, 2, 4, 8, 16, and 32 g·N·m−2·year−1) on canopy CUE (the ratio of net primary productivity [NPP] to gross primary productivity [GPP]) and ecosystem CUE (the ratio of net ecosystem productivity [NEP] to GPP) in an alpine meadow on the Tibetan Plateau in 2014–2016. Over the 3 years, nitrogen addition treatments did not change canopy CUE or ecosystem CUE in comparing with the control, although it significantly increased GPP, NPP, and NEP; those components of CUE had the same response patterns to N addition rates, which shifted from linear responses in the first year to saturation responses thereafter. Moreover, GPP showed a positive linear relationship with NEP, NPP, ecosystem respiration, and autotrophic respiration under each N addition treatment with no changes in slope. The inherent coupling between GPP and ecosystem respiration, as well as GPP and autotrophic respiration, made CUE less sensitive to N addition than carbon fluxes themselves. The conclusions challenge the widely held hypothesis that ecosystem CUE increases with N addition. This study provides the first empirical evidences on the proposition that CUE is insensitive to N availability, which is of importance in model construction and parameterization. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/113442
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China; Department of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Institute of Qinghai-Tibetan Plateau, Southwest University for Nationalities, Chengdu, China
Recommended Citation:
Ma F.,Song B.,Zhang F.,et al. Ecosystem Carbon Use Efficiency Is Insensitive to Nitrogen Addition in an Alpine Meadow[J]. Journal of Geophysical Research: Biogeosciences,2018-01-01,123(8)