Canopy attributes of desert grassland and transition communities derived from multiangular airborne imagery

摘要: Abstract The surface bidirectional reflectance distribution function (BRDF) contains valuable information on canopy physiognomy for desert grassland and grass–shrub transition communities. This may be accessed by inverting a BRDF model against sets of observations, which encompass important variations in viewing illumination angles. paper shows that structural attributes can derived through inversion the Simple Geometric Model (SGM) developed this paper. It is difficult to sample features from ground because discontinuous nature canopies long intrinsic length scales remotely sensed spectral measures (>10 m). A multispectral digital camera was therefore used derive spatial multiangular data air SGM validated inverted with these. also using 3-D radiosity simulations driven maps field-measured plant dimensions. interpretation retrieved parameter (shrub density, shrub width height) reveals structure within grassland–shrubland communities, are clearly related optical high resolution panchromatic vegetation index images. To our knowledge, reports first attempts acquire landscapes multiple view angle at less than 1 km. results point further opportunities exploit spaceborne sensors such as Multiangle Imaging SpectroRadiometer (MISR) Compact High Resolution Spectrometer (CHRIS) NASA Terra European Space Agency's PROBA satellites, respectively.