Temporal versus spatial variation in leaf reflectance under changing water stress conditions

Leaf reflectance changes associated with changes in water stress were analysed in two separate experiments. Results indicate that the variation in reflectance among collections of leaves of a given species all at the same level of water stress is at least as great as the variation in reflectance associated with changesin water stress for a givenleaf collection of that species. The implicationis that results from leaf reflectance-water stress studies have only limited applicability to the remote sensing of plant canopy water stress.