HR: 16:45h
AN: H54C-04    [Abstracts]
TI: Aspects of Radiation Budget, Subsurface Lateral Moisture Exchange, and Vegetation Function in Areas of Complex Topography.
AU: * Ivanov, V Y
EM: viva@mit.edu
AF: Ralph M. Parsons Laboratory, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 15 Vassar St., Cambridge, MA 02139 United States
AU: Bras, R L
EM: rlbras@mit.edu
AF: Ralph M. Parsons Laboratory, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 15 Vassar St., Cambridge, MA 02139 United States
AU: Istanbulluoglu, E
EM: erkan@mit.edu
AF: Ralph M. Parsons Laboratory, Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 15 Vassar St., Cambridge, MA 02139 United States
AU: Vivoni, E R
EM: vivoni@nmt.edu
AF: Department of Earth and Environmental Science New Mexico Institute of Mining and Technology, 801 Leroy Place, MSEC 244, Socorro, NM 87801 United States
AB: There is evidence that topography strongly affects the state, function, and distribution of vegetation by controlling incoming solar radiation and lateral redistribution of soil moisture. However, numerical experiments studying the effects that a topography can have on vegetation have oversimplified the treatment of topography and/or the representation of vegetation. We investigate the control of topography on vegetation state and stress via detailed modeling of radiation and soil moisture budgets across the varied terrain of a watershed. A detailed vegetation-hydrology model parameterizes the processes of canopy radiative transfer and rainfall interception and couples the processes of infiltration and evapotranspiration to photosynthesis via moisture uptake through a root systems with varied profiles. The model is applied on a continuous basis to synthetic watersheds of topography dominated by either convex or concave hillslopes. The numerical analysis is carried out for several plant functional types and soils. Inferences from the spatially-distributed dynamics are used to examine topographic niches favorable to vegetation.
DE: 1800 HYDROLOGY
DE: 1851 Plant ecology
DE: 1866 Soil moisture
DE: 1878 Water/energy interactions
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting