DOI: 10.1029/2018GB006001
论文题名: Soil Organic Matter Temperature Sensitivity Cannot be Directly Inferred From Spatial Gradients
作者: Abramoff R.Z. ; Torn M.S. ; Georgiou K. ; Tang J. ; Riley W.J.
刊名: Global Biogeochemical Cycles
ISSN: 0886-6236
EISSN: 1944-9224
出版年: 2019
卷: 33, 期: 6 语种: 英语
英文关键词: algorithm
; carbon sequestration
; climate change
; environmental gradient
; global warming
; machine learning
; microbial activity
; organic compound
; sensitivity analysis
; soil carbon
; soil organic matter
; soil temperature
; spatial analysis
学科: climate change
; microbial dynamics
; organomineral associations
; soil carbon
; soil modeling
; temperature sensitivity
中文摘要: Developing and testing decadal-scale predictions of soil response to climate change is difficult because there are few long-term warming experiments or other direct observations of temperature response. As a result, spatial variation in temperature is often used to characterize the influence of temperature on soil organic carbon (SOC) stocks under current and warmer temperatures. This approach assumes that the decadal-scale response of SOC to warming is similar to the relationship between temperature and SOC stocks across sites that are at quasi steady state; however, this assumption is poorly tested. We developed four variants of a Reaction-network-based model of soil organic matter and microbes using measured SOC stocks from a 4,000-km latitudinal transect. Each variant reflects different assumptions about the temperature sensitivities of microbial activity and mineral sorption. All four model variants predicted the same response of SOC to temperature at steady state, but different projections of transient warming responses. The relative importance of Qmax, mean annual temperature, and net primary production, assessed using a machine-learning algorithm, changed depending on warming duration. When mineral sorption was temperature sensitive, the predicted average change in SOC after 100 years of 5 °C warming was −18% if warming decreased sorption or +9% if warming increased sorption. When microbial activity was temperature sensitive but mineral sorption was not, average site-level SOC loss was 5%. We conclude that spatial climate gradients of SOC stocks are insufficient to constrain the transient response; measurements that distinguish process controls and/or observations from long-term warming experiments, especially mineral fractions, are needed. ©2019. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/160123
Appears in Collections: 气候变化与战略
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作者单位: Lawrence Berkeley National Laboratory, Berkeley, CA, United States; Laboratoire des Sciences du Climat et de l'Environnment, Orme des Merisiers, Gif-sur-Yvette, France; University of California, Berkeley, Berkeley, CA, United States
Recommended Citation:
Abramoff R.Z.,Torn M.S.,Georgiou K.,et al. Soil Organic Matter Temperature Sensitivity Cannot be Directly Inferred From Spatial Gradients[J]. Global Biogeochemical Cycles,2019-01-01,33(6)