DOI: 10.1111/gcb.13489
论文题名: The sensitivity of soil respiration to soil temperature, moisture, and carbon supply at the global scale
作者: Hursh A. ; Ballantyne A. ; Cooper L. ; Maneta M. ; Kimball J. ; Watts J.
刊名: Global Change Biology
ISSN: 13541013
出版年: 2017
卷: 23, 期: 5 起始页码: 2090
结束页码: 2103
语种: 英语
英文关键词: climate change
; global carbon cycle
; primary productivity
; soil moisture
; soil respiration
; soil temperature
英文摘要: Soil respiration (Rs) is a major pathway by which fixed carbon in the biosphere is returned to the atmosphere, yet there are limits to our ability to predict respiration rates using environmental drivers at the global scale. While temperature, moisture, carbon supply, and other site characteristics are known to regulate soil respiration rates at plot scales within certain biomes, quantitative frameworks for evaluating the relative importance of these factors across different biomes and at the global scale require tests of the relationships between field estimates and global climatic data. This study evaluates the factors driving Rs at the global scale by linking global datasets of soil moisture, soil temperature, primary productivity, and soil carbon estimates with observations of annual Rs from the Global Soil Respiration Database (SRDB). We find that calibrating models with parabolic soil moisture functions can improve predictive power over similar models with asymptotic functions of mean annual precipitation. Soil temperature is comparable with previously reported air temperature observations used in predicting Rs and is the dominant driver of Rs in global models; however, within certain biomes soil moisture and soil carbon emerge as dominant predictors of Rs. We identify regions where typical temperature-driven responses are further mediated by soil moisture, precipitation, and carbon supply and regions in which environmental controls on high Rs values are difficult to ascertain due to limited field data. Because soil moisture integrates temperature and precipitation dynamics, it can more directly constrain the heterotrophic component of Rs, but global-scale models tend to smooth its spatial heterogeneity by aggregating factors that increase moisture variability within and across biomes. We compare statistical and mechanistic models that provide independent estimates of global Rs ranging from 83 to 108 Pg yr−1, but also highlight regions of uncertainty where more observations are required or environmental controls are hard to constrain. © 2016 John Wiley & Sons Ltd
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60965
Appears in Collections: 影响、适应和脆弱性
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作者单位: Department of Ecosystem and Conservation Sciences, College of Forestry and Conservation, University of Montana, 32 Campus Drive, Missoula, MT, United States
Recommended Citation:
Hursh A.,Ballantyne A.,Cooper L.,et al. The sensitivity of soil respiration to soil temperature, moisture, and carbon supply at the global scale[J]. Global Change Biology,2017-01-01,23(5)