DOI: 10.1007/s10533-014-0021-z
Scopus记录号: 2-s2.0-84911806045
论文题名: Nitrogen fixation can exceed inorganic nitrogen uptake fluxes in oligotrophic streams
作者: Kunza L.A. ; Hall R.O. ; Jr.
刊名: Biogeochemistry
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2014
卷: 121, 期: 3 起始页码: 537
结束页码: 549
语种: 英语
英文关键词: Algal assemblage dynamics
; Ammonium uptake
; N cycling
; Nitrate uptake
; Nitrogen fixation
; Streams
Scopus关键词: ammonium
; biofilm
; concentration (composition)
; denitrification
; inorganic nitrogen
; nitrate
; nitrogen cycle
; nitrogen fixation
; oligotrophic environment
; stream
; Ditch Creek
; Grand Teton National Park
; United States
; Wyoming
; algae
英文摘要: Nitrogen fixation can be a dominant flux of nitrogen (N) input providing up to 97 % of new N into some terrestrial and up to 82 % into some aquatic ecosystems, yet N2 fixation is rarely considered in the context of other N cycling fluxes. We compared N2 fixation with dissolved inorganic N (DIN) uptake fluxes in several streams. We measured N2 fixation in nine streams in Grand Teton National Park, Wyoming, USA and surrounding areas and we compared our estimates to the ammonium (NH+4)uptake, nitrate (NO-3) uptake, and denitrification estimates from the literature for those streams. N2 fixation was negligible or below detection in the four streams with NO-3 concentrations >20 μg NO-3 -N L−1. N2 fixation exceeded NO-3 uptake in two of the nine streams and NH+4 uptake in one stream. To further examine the relationship between N2 fixation and DIN uptake, we chose Ditch Creek, which is a low-N stream (<5 µg DIN-N L−1) with high rates of N2 fixation. We measured N2 fixation, NH+4 uptake, and NO-3 uptake biweekly throughout one summer. In Ditch Creek, DIN uptake exceeded N2 fixation at the beginning and end of the summer, but from July to the beginning of September N2 fixation was up to eight times greater than DIN uptake. The epilithic biofilm in Ditch Creek accumulated 1.5 g N m−2 throughout the summer, and N2 fixation may have contributed up to 73 % of that accumulation. Ditch Creek N2 fixation surpassed denitrification for both Ditch Creek and many streams. N2 fixation can be a dominant flux in low-N stream ecosystems. © 2014, Springer International Publishing Switzerland. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83677
Appears in Collections: 气候减缓与适应 气候变化事实与影响
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作者单位: Program in Ecology, Department of Zoology and Physiology, University of Wyoming, 1000 E. University Avenue, Laramie, WY, United States; Department of Chemistry and Applied Biological Sciences, Atmospheric and Environmental Sciences program, Rapid City, SD, United States
Recommended Citation:
Kunza L.A.,Hall R.O.,Jr.. Nitrogen fixation can exceed inorganic nitrogen uptake fluxes in oligotrophic streams[J]. Biogeochemistry,2014-01-01,121(3)