This research will test the hypothesis that photosynthetic efficiency and capacity can be predicted from "physiological reflectance indices" derived from spectral reflectance of vegetation. This hypothesis assumes that leaves and canopies follow ecophysiological "rules" of light energy distribution resulting in consistent relationships between PAR distribution and photosynthetic fluxes. Experimental studies employing concurrent measurements of spectral reflectance, leaf gas exchange and fluorescence on evergreen species will develop a mechanistic understanding of relationships between photosynthetic regulation and spectral reflectance. These experiments will be used to derive a leaf-level model incorporating "physiological reflectance indices" linking spectral reflectance to photosynthetic fluxes. Experimental comparisons of leaf and canopy reflectance will provide algorithms for predicting photosynthetic efficiency and capacity from canopy spectral reflectance. %%% This work enables a young and very promising ecosystem scientist utilizing minority students at an undergraduate institution. Although the most understanding of physiological function at the leaf and canopy levels, the conclusions may benefit future studies of vegetation-atmosphere interactions involving remote sensing at the landscape level.
