title: Global remote sensing of water-chlorophyll ratio in terrestrial plant leaves.
abstract: I evaluated the use of global remote sensing techniques for estimating plant leaf chlorophyll a + b (C(ab); μg cm(-2)) and water (C(w); mg cm(-2)) concentrations as well as the ratio of C(w)/C(ab) with the PROSAIL model under possible distributions for leaf and soil spectra, leaf area index (LAI), canopy geometric structure, and leaf size. First, I estimated LAI from the normalized difference vegetation index. I found that, at LAI values <2, C(ab), C(w), and C(w)/C(ab) could not be reliably estimated. At LAI values >2, C(ab) and C(w) could be estimated for only restricted ranges of the canopy structure; however, the ratio of C(w)/C(ab) could be reliably estimated for a variety of possible canopy structures with coefficients of determination (R(2)) ranging from 0.56 to 0.90. The remote estimation of the C(w)/C(ab) ratio from satellites offers information on plant condition at a global scale.
authors.affiliation: Center for Far Eastern Studies and Graduate School of Science and Engineering (Science), University of Toyama 3190 Gofuku, Toyama, 930-8555, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Kushida
keywords: Leaf area index; leaf chlorophyll concentration; leaf water concentration; radiative transfer; remote sensing