© 2002 Heron Publishing—Victoria, Canada
How the environment, canopy structure and canopy physiological functioning influence carbon, water and energy fluxes of a
temperate broad-leaved deciduous forest—an assessment with the biophysical model CANOAK
Dennis D. Baldocchi (1, 2), Kell B. Wilson (3) and Lianhong Gu (1)
1. Ecosystem Science Division, Department of Environmental Science, Policy and Management, 151 Hilgard Hall, University of California-Berkeley,
Berkeley, CA 94720, USA / 2. Author to whom correspondence should be addressed (Baldocchi@nature.berkeley.edu) / 3. Atmospheric Turbulence and Diffusion Division, NOAA, P.O. Box 2456, Oak Ridge, TN 37831, USA / Received August 3, 2001; accepted March 6, 2002; published online October 1, 2002
Summary
This paper focuses on how canopy structure, its physiological functioning and the environment interact to control and drive
the exchange of carbon dioxide (CO2) and water vapor between a temperate forest stand and the atmosphere. First, we present an overview of how temporal and spatial
variations in canopy structure (e.g., leaf area index, species, leaf inclination angles, leaf clumping) and physiological
functioning (e.g., maximal stomatal conductance, photosynthetic capacity) modulate CO2 and water vapor fluxes. Then, with the biophysical model CANOAK, we quantify the effects of leaf dimension and thickness,
vertical variations in leaf area and photosynthetic capacity, leaf clumping, leaf inclination angles, photosynthetic capacity,
stomatal conductance and weather on the annual sums of CO2, water vapor and sensible heat exchange. Finally, we discuss how much detail is needed in a model to predict fluxes of CO2 and water vapor with acceptable fidelity.
Keywords:
biocomplexity, biosphere–atmosphere interactions, canopy photosynthesis, ecophysiology, evaporation.
