International Journal of Biometeorology

, Volume 49, Issue 6, pp 377–387

Predicting the onset of net carbon uptake by deciduous forests with soil temperature and climate data: a synthesis of FLUXNET data

  • Dennis D. Baldocchi
  • T. A. Black
  • P. S. Curtis
  • E. Falge
  • J. D. Fuentes
  • A. Granier
  • L. Gu
  • A. Knohl
  • K. Pilegaard
  • H. P. Schmid
  • R. Valentini
  • K. Wilson
  • S. Wofsy
  • L. Xu
  • S. Yamamoto
Original Article

DOI: 10.1007/s00484-005-0256-4

Cite this article as:
Baldocchi, D.D., Black, T.A., Curtis, P.S. et al. Int J Biometeorol (2005) 49: 377. doi:10.1007/s00484-005-0256-4

Abstract

We tested the hypothesis that the date of the onset of net carbon uptake by temperate deciduous forest canopies corresponds with the time when the mean daily soil temperature equals the mean annual air temperature. The hypothesis was tested using over 30 site-years of data from 12 field sites where CO2 exchange is being measured continuously with the eddy covariance method. The sites spanned the geographic range of Europe, North America and Asia and spanned a climate space of 16°C in mean annual temperature. The tested phenology rule was robust and worked well over a 75 day range of the initiation of carbon uptake, starting as early as day 88 near Ione, California to as late as day 147 near Takayama, Japan. Overall, we observed that 64% of variance in the timing when net carbon uptake started was explained by the date when soil temperature matched the mean annual air temperature. We also observed a strong correlation between mean annual air temperature and the day that a deciduous forest starts to be a carbon sink. Consequently we are able to provide a simple phenological rule that can be implemented in regional carbon balance models and be assessed with soil and temperature outputs produced by climate and weather models.

Keywords

PhenologyEddy covarianceCO2 exchangeCanopy photosynthesis

Copyright information

© ISB 2005

Authors and Affiliations

  • Dennis D. Baldocchi
    • 1
  • T. A. Black
    • 2
  • P. S. Curtis
    • 3
  • E. Falge
    • 4
  • J. D. Fuentes
    • 5
  • A. Granier
    • 6
  • L. Gu
    • 7
  • A. Knohl
    • 8
    • 16
  • K. Pilegaard
    • 9
  • H. P. Schmid
    • 10
  • R. Valentini
    • 11
  • K. Wilson
    • 12
  • S. Wofsy
    • 13
  • L. Xu
    • 1
    • 15
  • S. Yamamoto
    • 14
  1. 1.Ecosystem Science Division, Department of Environmental Science, Policy and ManagementUniversity of CaliforniaBerkeleyUSA
  2. 2.Faculty of Agricultural SciencesUniversity of British ColumbiaVancouverCanada
  3. 3.Department of Evolution, Ecology & Organismal BiologyOhio State UniversityColumbusUSA
  4. 4.Bayreuth UniversityBayreuthGermany
  5. 5.Department of Environmental SciencesUniversity of VirginiaCharlottesvilleUSA
  6. 6.INRAChampenouxFrance
  7. 7.Environmental Science DivisionOak Ridge National LaboratoryOak RidgeUSA
  8. 8.Max Planck Institute for BiogeochemistryJenaGermany
  9. 9.RISOERoskildeDenmark
  10. 10.Department of GeographyIndiana UniversityBloomingtonUSA
  11. 11.Department of Forest Science and EnvironmentUniversita’ di TusciaViterboItaly
  12. 12.Atmospheric Turbulence and Diffusion DivisionNOAAOak RidgeUSA
  13. 13.Department of Earth and Planetary ScienceHarvard UniversityCambridgeUSA
  14. 14.National Institute of Advanced Industrial Science and TechnologyTsukubaJapan
  15. 15.Present address: LICORLincolnUSA
  16. 16.Present address: ESPMUniversity of CaliforniaBerkeleyUSA