|Zara, Pedro - SSAI|
|Hollinger, Steven - ILLINOIS STATE WATER SUR|
Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: November 4, 1999
Publication Date: December 4, 1999
Technical Abstract: Biophysical parameters, such as leaf area index (LAI), biomass and fractions of absorbed photosynthetically active radiation (fAPAR) are required for use in advanced global models of climate, hydrology, biogeochemistry, and ecology. These variables describe vegetation canopy density and structure, and are related to functional process rates of energy and mass exchange. Both LAI and fPAR have been used extensively as satellite derived parameters for calculation of surface photosynthesis, evapotranspiration, and net primary production. Current procedures of retrieving these parameters from satellite data are based on statistical relationship with spectral vegetation indices derived from a combination of spectral reflectance measurements. An algorithm to retrieve these surface parameters by coupling satellite data with a radiative transfer model will be presented. The procedure developed was applied on a 50x300 km area in the Southern Great Plains to generate fields of LAI, biomass and fPAR using Landsat TM images acquired on three dates in 1997. The resulting fields of LAI and fPAR were verified with actual ground measurements collected at the SGP97 experiment.