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| Titel |
Global spatiotemporal distribution of soil respiration modeled using a global database |
| VerfasserIn |
S. Hashimoto, N. Carvalhais, A. Ito, M. Migliavacca, K. Nishina, M. Reichstein |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1726-4170
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| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 12, no. 13 ; Nr. 12, no. 13 (2015-07-09), S.4121-4132 |
| Datensatznummer |
250118017
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| Publikation (Nr.) |
 copernicus.org/bg-12-4121-2015.pdf |
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| Zusammenfassung |
| The flux of carbon dioxide from the soil to the atmosphere (soil respiration)
is one of the major fluxes in the global carbon cycle. At present, the
accumulated field observation data cover a wide range of geographical
locations and climate conditions. However, there are still large
uncertainties in the magnitude and spatiotemporal variation of global soil
respiration. Using a global soil respiration data set, we developed a
climate-driven model of soil respiration by modifying and updating Raich's
model, and the global spatiotemporal distribution of soil respiration was
examined using this model. The model was applied at a spatial resolution of
0.5°and a monthly time step. Soil respiration was divided into the
heterotrophic and autotrophic components of respiration using an empirical
model. The estimated mean annual global soil respiration was
91 Pg C yr−1 (between 1965 and 2012; Monte Carlo 95 % confidence
interval: 87–95 Pg C yr−1) and increased at the rate of
0.09 Pg C yr−2. The contribution of soil respiration from boreal
regions to the total increase in global soil respiration was on the same
order of magnitude as that of tropical and temperate regions, despite a lower
absolute magnitude of soil respiration in boreal regions. The estimated
annual global heterotrophic respiration and global autotrophic respiration
were 51 and 40 Pg C yr−1, respectively. The global soil respiration
responded to the increase in air temperature at the rate of
3.3 Pg C yr−1 °C−1, and Q10 = 1.4. Our study scaled
up observed soil respiration values from field measurements to estimate
global soil respiration and provide a data-oriented estimate of global soil
respiration. The estimates are based on a semi-empirical model parameterized
with over one thousand data points. Our analysis indicates that the climate
controls on soil respiration may translate into an increasing trend in global
soil respiration and our analysis emphasizes the relevance of the soil carbon flux from
soil to the atmosphere in response to climate change. Further approaches
should additionally focus on climate controls in soil respiration in
combination with changes in vegetation dynamics and soil carbon stocks, along
with their effects on the long temporal dynamics of soil respiration. We
expect that these spatiotemporal estimates will provide a benchmark for
future studies and also help to constrain process-oriented models. |
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