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| Titel |
Global convergence in the temperature sensitivity of respiration at ecosystem level |
| VerfasserIn |
Miguel Mahecha, Markus Reichstein, Nuno Carvalhais, Gitta Lasslop, Holger Lange, Sonia Seneviratne, Mirco Migliavacca, Rodrigo Vargas |
| Konferenz |
EGU General Assembly 2010
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250042369
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| Zusammenfassung |
| The release of CO2 from the land surface—the “terrestrial ecosystem respiration”—constitutes a
major flux in the global carbon cycle, counterbalancing photosynthetic CO2 uptake.
Understanding the dynamics of the underlying processes, in particular, determining the
sensitivity of respiratory processes to temperature is central for quantifying the
climate–carbon cycle feedback. However, retrieving the “intrinsic” temperature response of
ecosystem respiration is complicated by the fact that observed CO2 fluxes and meteorological
drivers vary on multiple time scales. This multiscale variability induces confounding
effects that hamper the investigation of such temperature sensitivities in conventional
model–data synthesis approaches. We demonstrate how a multiscale approach is
needed to overcome problems of process identification when confounding factors
operate on different time scales and apply it to the widely used empirical Q10 model.
Here we approximate the “intrinsic" temperature sensitivity (Q10) of terrestrial
ecosystem respiration across 60 FLUXNET sites in different ecosystems. Our results
suggest that Q10 is largely temperature invariant, does not depend on plant functional
types and is confined to values around 1.5. These results resolve the long standing
debate how to parameterize the temperature sensitivity of respiratory processes in
current terrestrial biosphere models. We expect the presented model–data fusion
strategy to be of relevance for understanding various ecosystem–atmosphere feedback
systems. |
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