Relationships between reflectances at coarse and fine resolution on heterogeneous landscapes

The description of ecosystem structure and functioning is necessary in view of the monitoring of vegetation resources dynamics. It is therefore necessary to have spatial and temporal resolutions allowing respectively the characterization of the horizontal structure and the functional cycles. The images from NOAA-AVHRR are largely used for monitoring vegetation. Mixed pixel reflectance obtained using moderate spatial resolution instrument can be approximated by using a linear mixture model. The land use information obtained from high spatial resolution data allows the deconvolution of the response of a mixed pixel into the different components responses. A methodological adjustment has been performed over a spatially complex area in the West Africa. For this study, M.S.R data have been obtained through the degradation of SPOT images. This simulation gave the opportunity to check all the parameters of the model and therefore to testify its reliability and its sensitivity