Title :
Estimation of forest canopy leaf area index using directional ASAS measurements
Author :
Johnson, Lee F. ; Peterson, David L.
Author_Institution :
Johnson Controls World Services, NASA Ames Res. Center, Moffett Field, CA, USA
Abstract :
Coniferous forest canopy reflectance was derived from radiance data collected the Advanced Solid-State Array Spectroradiometer (ASAS). Red and near-infrared (NIR) responses were examined as a function of view zenith angle (θV), solar zenith angle (θ S), and site characteristics. Relationships were formulated between the normalized difference vegetation index (NDVI) and canopy leaf area index (LAI). It is suggested that the offnadir NDVI is a more stable estimator of LAI than is the nadir-view NDVI
Keywords :
forestry; geophysical techniques; infrared imaging; remote sensing; Advanced Solid-State Array Spectroradiometer; IR visible infrared; LAI; airborne method; canopy; directional ASAS; forest forestry; geophysical measurement technique; land surface; leaf area index using; light reflectance; nadir-view illumination direction; normalized difference vegetation index NDVI; offnadir; optical imaging; red; remote sensing; solar zenith angle; terrain mapping; vegetation mapping NIR; view angle; view zenith angle; Area measurement; Atmospheric modeling; Data acquisition; Iron; NASA; Reflectivity; Sensor arrays; Solid state circuits; Spectroradiometers; Vegetation;
Conference_Titel :
Geoscience and Remote Sensing Symposium, 1994. IGARSS '94. Surface and Atmospheric Remote Sensing: Technologies, Data Analysis and Interpretation., International
Conference_Location :
Pasadena, CA
Print_ISBN :
0-7803-1497-2
DOI :
10.1109/IGARSS.1994.399575
