Determination of the Vegetation Hotspot Diurnal and Seasonal Change by Real Scene Models
植被冠层热点的季相和日相变化

The vegetation hotspot dependence on its stucture at various times in one day and various growth periods is investigated in this paper. We simulate the interaction of light and vegetation based on three dimensional plant canopies.Our approach consists of four processes. Firstly,the biophysical parameters,such as corn plant height,leaf base height,size of leaf,and shape of leaf,are measured on field,and the statistics of the parameters is obtained based on the measurement. Secondly,the three dimensional structure of canopy is built by the CSM (Computer Scene Model)according to the statistics under a pixel configuration,such as planting by row or by random. Thirdly,the zenith and azimuth of sun are calculated for the simulated site on earth. Fourthly,hotspots and bi directional reflectance distribution functions are calculated by the LIM (Light Interception Model)under various sun and viewing geometric conditions. Finally we evaluate diurnal consecutive hotspot and seasonal consecutive hotspot. The characteristic and scientific objectives of hotspot satellite Triana also are introduced. The simulated result will improve our understanding about the Triana data,and help us to use the dada effectively.