Spectral vegetation relationships in a tropical rain forestJordan's (1969) spectral method of leaf-area index determination from measurements of the transmitted light at the forest floor is evaluated under a wide variety of illumination conditions in the Luquillo Rain Forest of Puerto Rico, using a hand-held radiometer. Previously suggested 'correction factors' for temporal adjustment were found to degrade the data. Quantitative use of the method was found to be restricted to high sun periods. Data collected under uniformly overcast conditions were of greater stability than under clear skies, however, stability was impaired by changes in cloud thickness. Care must be taken to minimize irradiational variability and to adquately sample the spatial variability.
Document ID
19800036079
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Holben, B. N. (NASA Goddard Space Flight Center Greenbelt, MD, United States)
Tucker, C. T. (NASA Goddard Space Flight Center Earth Resources Branch, Greenbelt, Md., United States)