DOI: 10.1111/gcb.12328
论文题名: Vegetation feedbacks of nutrient addition lead to a weaker carbon sink in an ombrotrophic bog
作者: Larmola T. ; Bubier J.L. ; Kobyljanec C. ; Basiliko N. ; Juutinen S. ; Humphreys E. ; Preston M. ; Moore T.R.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2013
卷: 19, 期: 12 起始页码: 3729
结束页码: 3739
语种: 英语
英文关键词: C balance
; CO2
; Decomposition
; Nitrogen
; Peatland
; Photosynthesis
; Respiration
; Sphagnum
; Substrate-induced respiration
Scopus关键词: bog
; carbon balance
; carbon dioxide
; carbon sequestration
; carbon sink
; decomposition
; moss
; nitrogen
; nutrient
; ombrotrophic environment
; peatland
; photosynthesis
; respiration
; vegetation
; Canada
; Mer Bleue
; Ontario [Canada]
; Bryophyta
; Sphagnum
; Tracheophyta
; carbon dioxide
; nitrogen
; phosphorus
; potassium
; article
; breathing
; C balance
; Canada
; carbon sequestration
; decomposition
; ecosystem
; metabolism
; peatland
; photosynthesis
; plant
; season
; Sphagnum
; substrate-induced respiration
; wetland
; C balance
; CO2
; decomposition
; nitrogen
; peatland
; photosynthesis
; respiration
; Sphagnum
; substrate-induced respiration
; Carbon Dioxide
; Carbon Sequestration
; Ecosystem
; Nitrogen
; Ontario
; Phosphorus
; Plants
; Potassium
; Seasons
; Wetlands
英文摘要: To study vegetation feedbacks of nutrient addition on carbon sequestration capacity, we investigated vegetation and ecosystem CO2 exchange at Mer Bleue Bog, Canada in plots that had been fertilized with nitrogen (N) or with N plus phosphorus (P) and potassium (K) for 7-12 years. Gross photosynthesis, ecosystem respiration, and net CO2 exchange were measured weekly during May-September 2011 using climate-controlled chambers. A substrate-induced respiration technique was used to determine the functional ability of the microbial community. The highest N and NPK additions were associated with 40% less net CO2 uptake than the control. In the NPK additions, a diminished C sink potential was due to a 20-30% increase in ecosystem respiration, while gross photosynthesis rates did not change as greater vascular plant biomass compensated for the decrease in Sphagnum mosses. In the highest N-only treatment, small reductions in gross photosynthesis and no change in ecosystem respiration led to the reduced C sink. Substrate-induced microbial respiration was significantly higher in all levels of NPK additions compared with control. The temperature sensitivity of respiration in the plots was lower with increasing cumulative N load, suggesting more labile sources of respired CO2. The weaker C sink potential could be explained by changes in nutrient availability, higher woody : foliar ratio, moss loss, and enhanced decomposition. Stronger responses to NPK fertilization than to N-only fertilization for both shrub biomass production and decomposition suggest that the bog ecosystem is N-P/K colimited rather than N-limited. Negative effects of further N-only deposition were indicated by delayed spring CO2 uptake. In contrast to forests, increased wood formation and surface litter accumulation in bogs seem to reduce the C sink potential owing to the loss of peat-forming Sphagnum. © 2013 John Wiley & Sons Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/62262
Appears in Collections: 影响、适应和脆弱性
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作者单位: Environmental Studies Department, Mount Holyoke College, 50 College Street, South Hadley, MA, 01075, United States; Department of Geography, University of Toronto Mississauga, 3359 Mississauga Road North, Mississauga, ON, L5L 1C6, Canada; Department of Forest Sciences, University of Helsinki, Latokartanonkaari 7, Helsinki, FI- 00014, Finland; Department of Geography and Environmental Studies, Carleton University, 1125 Colonel By Dr, Ottawa, ON, K1S 5B6, Canada; Department of Geography, McGill University, 805 Sherbrooke Street West, Montreal, QC, H3A 0B9, Canada
Recommended Citation:
Larmola T.,Bubier J.L.,Kobyljanec C.,et al. Vegetation feedbacks of nutrient addition lead to a weaker carbon sink in an ombrotrophic bog[J]. Global Change Biology,2013-01-01,19(12)