DOI: 10.1111/gcb.12793
论文题名: Rapid carbon turnover beneath shrub and tree vegetation is associated with low soil carbon stocks at a subarctic treeline
作者: Parker T.C. ; Subke J.-A. ; Wookey P.A.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2015
卷: 21, 期: 5 起始页码: 2070
结束页码: 2081
语种: 英语
英文关键词: Betula
; Carbon inventory
; Dwarf birch
; Ectomycorrhiza
; Gas flux
; Shrub expansion
; Soil carbon cycling
; Subarctic
Scopus关键词: biomass
; carbon cycle
; carbon sequestration
; deciduous tree
; ectomycorrhiza
; flux measurement
; shrub
; soil carbon
; subarctic region
; treeline
; tundra
; vegetation
; Abisko
; Lapland [Eurasia]
; Norrbotten
; Sweden
; Betula
; Betula nana
; Betula pubescens
; Empetrum nigrum
; carbon
; carbon dioxide
; soil
; biomass
; birch
; carbon cycle
; chemistry
; climate change
; Ericaceae
; fungus
; growth, development and aging
; metabolism
; physiology
; soil
; Sweden
; tree
; tundra
; Betula
; Biomass
; Carbon
; Carbon Cycle
; Carbon Dioxide
; Climate Change
; Ericaceae
; Fungi
; Soil
; Sweden
; Trees
; Tundra
英文摘要: Climate warming at high northern latitudes has caused substantial increases in plant productivity of tundra vegetation and an expansion of the range of deciduous shrub species. However significant the increase in carbon (C) contained within above-ground shrub biomass, it is modest in comparison with the amount of C stored in the soil in tundra ecosystems. Here, we use a 'space-for-time' approach to test the hypothesis that a shift from lower-productivity tundra heath to higher-productivity deciduous shrub vegetation in the sub-Arctic may lead to a loss of soil C that out-weighs the increase in above-ground shrub biomass. We further hypothesize that a shift from ericoid to ectomycorrhizal systems coincident with this vegetation change provides a mechanism for the loss of soil C. We sampled soil C stocks, soil surface CO2 flux rates and fungal growth rates along replicated natural transitions from birch forest (Betula pubescens), through deciduous shrub tundra (Betula nana) to tundra heaths (Empetrum nigrum) near Abisko, Swedish Lapland. We demonstrate that organic horizon soil organic C (SOCorg ) is significantly lower at shrub (2.98 ± 0.48 kg m-2) and forest (2.04 ± 0.25 kg m-2) plots than at heath plots (7.03 ± 0.79 kg m-2). Shrub vegetation had the highest respiration rates, suggesting that despite higher rates of C assimilation, C turnover was also very high and less C is sequestered in the ecosystem. Growth rates of fungal hyphae increased across the transition from heath to shrub, suggesting that the action of ectomycorrhizal symbionts in the scavenging of organically bound nutrients is an important pathway by which soil C is made available to microbial degradation. The expansion of deciduous shrubs onto potentially vulnerable arctic soils with large stores of C could therefore represent a significant positive feedback to the climate system. © 2014 John Wiley & Sons Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/61593
Appears in Collections: 影响、适应和脆弱性
There are no files associated with this item.
作者单位: Biological and Environmental Sciences, School of Natural Sciences, University of Stirling, Stirling, United Kingdom; Department of Animal and Plant Sciences, Alfred Denny Building, University of Sheffield, Sheffield, United Kingdom; Environmental Sciences, School of Life Sciences, Heriot-Watt University, Edinburgh, United Kingdom
Recommended Citation:
Parker T.C.,Subke J.-A.,Wookey P.A.. Rapid carbon turnover beneath shrub and tree vegetation is associated with low soil carbon stocks at a subarctic treeline[J]. Global Change Biology,2015-01-01,21(5)