HR: 14:00h
AN: B43C-02 INVITED     [Abstracts]
TI: Linking leaf photosynthesis to eddy-covariance measured fluxes on complex terrain
AU: * Katul, G
EM: gaby@duke.edu
AF: Duke University, Nicholas School of the Environment and Earth Sciences, Box 90328, Duke University, Durham, NC 27705 United States
AU: Finnigan, J
EM: John.finnigan@csiro.au
AF: CSIRO Atmospheric Research, CSIRO Atmospheric Research, FC Pye Laboratory, Black Mountain, Canberra, ACT 2601 Austria
AU: Poggi, D
EM: davide.poggi@duke.edu
AF: Politecnico di Torino, Dipartimento di Idraulica, Trasporti ed Infrastrutture Civili Politecnico di Torino, Torino, 10129 Italy
AB: It is recognized that topography influences almost all aspects of forest-atmosphere carbon exchange, yet a limited number of studies considered the role of topography on the structure of turbulence within vegetation and its ultimate effect on photosynthesis and net ecosystem carbon fluxes. Here, we focus on the interplay between radiative transfer, flow dynamics, and eco-physiological controls on CO2 sources and sinks within a canopy volume on a gentle cosine hill. In particular, we address how does topography alter the forest-atmosphere CO2 exchange rate when compared to uniform flat terrain. Towards this end, we present results from a first order closure model that explicitly accounts for the flow dynamics, radiative transfer, and the nonlinear eco-physiological processes within the canopy volume. We compare the first order closure model calculations of advective fluxes with: 1) recent field experiments on CO2 transport conducted in Tharandt, Germany; and 2) recent flume experiments for momentum transport in the presence and absence of a dense canopy on a train of hills. Implications for CO2 flux monitoring on complex topography are also discussed in the context of the relative roles of advective terms and the local CO2 sources and sinks.
DE: 3379 Turbulence
DE: 1851 Plant ecology
DE: 1878 Water/energy interactions
DE: 1615 Biogeochemical processes (4805)
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting