文献类型：期刊文献

英文题名：Fates of atmospheric deposited nitrogen in an Asian tropical primary forest

作者：Wang, Ang[1,6,7] Zhu, Weixing[1,3] Gundersen, Per[4] Phillips, Oliver L.[5] Chen, Dexiang[2] Fang, Yunting[1,6]

第一作者：Wang, Ang

通信作者：Chen, DX[1];Fang, YT[2]

机构：[1]Chinese Acad Sci, Inst Appl Ecol, CAS Key Lab Forest Ecol & Management, Shenyang 110164, Liaoning, Peoples R China;[2]Chinese Acad Forestry, Res Inst Trop Forestry, Guangzhou 510520, Guangdong, Peoples R China;[3]SUNY Binghamton, Dept Biol Sci, Binghamton, NY 13902 USA;[4]Univ Copenhagen, Dept Geosci & Nat Resource Management, DK-1958 Frederiksberg C, Denmark;[5]Univ Leeds, Sch Geog, Leeds LS2 9JT, W Yorkshire, England;[6]Qingyuan Forest CERN, Shenyang 110016, Liaoning, Peoples R China;[7]Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China

年份：2018

卷号：411

起止页码：213-222

外文期刊名：FOREST ECOLOGY AND MANAGEMENT

收录：;EI(收录号：20180704782659);Scopus(收录号：2-s2.0-85041463776);WOS:【SCI-EXPANDED(收录号:WOS:000426409100022)】；

基金：The work was financially supported by the National Key Research and Development Program of China (2016YFA0600802), the Strategic Priority Research Program of Chinese Academy of Sciences (XDB15020200), the Special Research Program of the Research Institute for Tropical Forestry of CAF (RITFYWZX2014-01), Key Research Program of Frontier Sciences of Chinese Academy of Sciences (QYZDB-SSW-DQC002), Overseas Scholar funding (31528003), the National Natural Science Foundation of China (31370464, 31422009, 31400386 and 31400422), Fundamental Research Funds of CAF (Nos. CAFYBB2014QB038). OLP acknowledges the support of European Research Council Advanced Grant 291585 (T-FORCES) and a Royal Society-Wolfson Research Merit Award. We would like to thank many students and field staff for assisting sampling and analyses. Prof. J. Titus from Binghamton University provided highly useful edits on the revision of this paper. Constructive comments by reviewers and the editor have greatly improved the quality of this paper. The work was jointly supported by the Jianfengling National Key Field Station.

语种：英文

外文关键词：N-15 tracer; Nitrogen deposition; Nitrogen retention; Plant uptake; Carbon sequestration; Total ecosystem recovery

摘要：The impacts of increasing nitrogen (N) deposition on forest ecosystems, including on carbon (C) sequestration, largely depend on the extent to which forests are N-limited and so whether and where deposited N is retained within the ecosystem. The N-15 tracer method can provide excellent insight into the ecosystem fates of N, but while it has been extensively used in temperate forests it has yet to be sufficiently employed in tropical forests, which are often thought not to be N-limited. Here, we used stable isotope (NH4+)-N-15 and (NO3-)-N-15 tracers applied as solutions to the forest floor to examine the fates of different forms of N in a tropical montane primary forest with low background atmospheric N deposition (6 kg N ha(-1) yr(-1)) in China. We found that a substantial amount of 15N was assimilated by plants over time and significantly more N-15 was recovered following (NO3-)-N-15 addition than following (NH4+)-N-15 addition: 7% and 16% of N-15 were recovered three months after the respective (NH4+)-N-15 and (NO3-)-N-15 tracer additions and 11% and 29% respectively after one year. In contrast to plants, the organic layer was only an important short-term sink for deposited N: while 21% and 12% of the N-15 from (NH4+)-N-15 and (NO3-)-N-15 additions were accumulated in the organic layer after three months, more than half of the retained N-15 was lost after one year. Mineral soil was the largest sink for deposited N, and the N-15 retained in soil was relatively stable over time for both N forms, with 39% and 32% of the initial N-15 input recovered after one year for (NH4+)-N-15 and (NO3-)-N-15 tracer additions, respectively. Overall, the total ecosystem N-15 recovery one year after the (NH4+)-N-15 and (NO3-)-N-15 tracer additions was large (60% and 66% respectively), and not significantly different from total recovery after three months, suggesting that a large proportion of deposited N could be retained in the longer term. Based on the measured fate of N-15 one year after labeling and the C:N ratios of different plant components, this tropical forest's carbon sequestration efficiency is calculated to be 17 kg C per kg N added, comparable to the values reported for temperate and boreal forests in Europe and North America and indicating substantial N limitation of this tropical forest. Our results suggest that anthropogenic N input in moderate levels may contribute to enhance C sequestration in some tropical forests, without significant long-term loss of N to the environment.