DOI: 10.1111/gcb.13804
论文题名: Experimentally increased nutrient availability at the permafrost thaw front selectively enhances biomass production of deep-rooting subarctic peatland species
作者: Keuper F. ; Dorrepaal E. ; van Bodegom P.M. ; van Logtestijn R. ; Venhuizen G. ; van Hal J. ; Aerts R.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2017
卷: 23, 期: 10 起始页码: 4257
结束页码: 4266
语种: 英语
英文关键词: belowground nitrogen
; climate change
; Empetrum hermaphroditum
; fertilization
; frozen soil
; permafrost thaw
; root uptake
; Rubus chamaemorus
Scopus关键词: Empetrum hermaphroditum
; Eriophorum vaginatum
; Rubus chamaemorus
英文摘要: Climate warming increases nitrogen (N) mineralization in superficial soil layers (the dominant rooting zone) of subarctic peatlands. Thawing and subsequent mineralization of permafrost increases plant-available N around the thaw-front. Because plant production in these peatlands is N-limited, such changes may substantially affect net primary production and species composition. We aimed to identify the potential impact of increased N-availability due to permafrost thawing on subarctic peatland plant production and species performance, relative to the impact of increased N-availability in superficial organic layers. Therefore, we investigated whether plant roots are present at the thaw-front (45 cm depth) and whether N-uptake (15N-tracer) at the thaw-front occurs during maximum thaw-depth, coinciding with the end of the growing season. Moreover, we performed a unique 3-year belowground fertilization experiment with fully factorial combinations of deep- (thaw-front) and shallow-fertilization (10 cm depth) and controls. We found that certain species are present with roots at the thaw-front (Rubus chamaemorus) and have the capacity (R. chamaemorus, Eriophorum vaginatum) for N-uptake from the thaw-front between autumn and spring when aboveground tissue is largely senescent. In response to 3-year shallow-belowground fertilization (S) both shallow- (Empetrum hermaphroditum) and deep-rooting species increased aboveground biomass and N-content, but only deep-rooting species responded positively to enhanced nutrient supply at the thaw-front (D). Moreover, the effects of shallow-fertilization and thaw-front fertilization on aboveground biomass production of the deep-rooting species were similar in magnitude (S: 71%; D: 111% increase compared to control) and additive (S + D: 181% increase). Our results show that plant-available N released from thawing permafrost can form a thus far overlooked additional N-source for deep-rooting subarctic plant species and increase their biomass production beyond the already established impact of warming-driven enhanced shallow N-mineralization. This may result in shifts in plant community composition and may partially counteract the increased carbon losses from thawing permafrost. © 2017 John Wiley & Sons Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60807
Appears in Collections: 影响、适应和脆弱性
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作者单位: Systems Ecology, Department of Ecological Science, VU University Amsterdam, Amsterdam, Netherlands; Department of Ecology and Environmental Science, Climate Impacts Research Centre, Umeå University, Abisko, Sweden; UR1158 AgroImpact, INRA, Barenton-Bugny, France; Institute of Environmental Sciences, Leiden University, Leiden, Netherlands
Recommended Citation:
Keuper F.,Dorrepaal E.,van Bodegom P.M.,et al. Experimentally increased nutrient availability at the permafrost thaw front selectively enhances biomass production of deep-rooting subarctic peatland species[J]. Global Change Biology,2017-01-01,23(10)