Comparative Study of Radiative and Carbon Fluxes at Three Ecosystems in Germany, Canada and Costa Rica (ComRadE)


Our understanding of forest ecosystem processes such as energy and carbon exchange is limited. The fraction of absorbed photosynthetically active radiation (FAPAR) by forest canopies is a crucial variable for assessing global carbon balances and currently there is an urgent need for reference data to validate satellite-derived FAPAR products. Overall, there exist only few studies combining radiation quantity, quality and carbon fluxes in forest ecosystems, despite the necessity of reliable data and process understanding as input for biogeochemical models under the aspect of ongoing climatic change.

The project ComRadE provided insights associated to carbon and energy fluxes in a boreal, a temperate, and a tropical dry forest. It also initiated a long-term collaboration between the involved institutes of the RWTH Aachen University (LFG Physical Geography and Climatology), the University of Alberta (Alberta Centre for Earth Observation Sciences) and the Research Center Jülich (Agrosphere Institute IBG-3) including the establishment of a long-term coordinated environmental measurement program of radiative fluxes.

In the meantime, it could be shown in a spruce forest in the Eifel, that the experimental set-up with PAR sensors in combination with sap flow sap flow measurements, correlations between the absorbed photosynthetic between the absorbed photosynthetically active radiation and the carbon carbon fluxes can be recorded and that these can also be linked to effects of water shortage due to drought. The results were published in 2023 and will be included in the project "MW³ - Standardised Monitoring of Standardised monitoring of growth responses of important forest tree species to extreme climatic events".


Funding IRS - International Research Space

Department of Geography RWTH Aachen, Department of Physical Geography and Climatology:

  • Prof. Dr. Michael Leuchner
  • Oliver Reitz, M.Sc.

University of Alberta, Centre for Earth Observation Sciences (CEOS):
Prof. Dr. Arturo Sanchez-Azofeifa

Research Center Jülich, Agrosphere Institute (IBG-3):
PD Dr. Heye Bogena, Dr. Alexander Graf