A Physical Model of the Bidirectional Reflectance of Vegetation Canopies 2. Inversion and Validation
نویسنده
چکیده
A physically based, analytical model of the bidirectional reflectance of porous media was derived in a companion paper (Verstraete et al., this issue). This model is validated against laboratory and ground-based measurements taken over two vegetation covers, both in the visible and near-infrared spectral regions. An inversion procedure, based on a nonlinear optimization technique, is used to infer the intrinsic optical properties of the leaves, as well as information on the morphology of the canopies, that is, on the geometrical arrangements of these scatterers in space. The model is then used to generate theoretical bidirectional reflectances, using the values of the relevant parameters retrieved from the inversion procedure, and these values compare favorably with the actual observations over the entire range of illumination and observation angles. The values of the parameters retrieved from the inversion procedure are discussed, validated against actual independent measurements, and interpreted in terms of the physical and morphological properties of the vegetation covers.
منابع مشابه
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