Fusion of Spatial and Temporal Information for Agricultural Land Use Identification - Preliminary Study for the VEGETATION Sensor

International audienceLaunched in March 1998 on the SPOT-4 platform, the VEGETATION sensor (VGT) has been designed for the analysis of vegetation dynamics. It provides daily images with 1km spatial resolution. Because of this daily sampling, it can be used for agricultural monitoring, with applications such as yield estimation and forecast, and detection of growth anomalies. These studies can furthermore be performed on large areas due to the large size of VGT scenes. The 1km spatial resolution, however, can be a problem when studying European agricultural areas: since agricultural parcels are usually relatively small, most VGT pixels contain several different land cover types and it is therefore necessary to perform pixel unmixing. For that purpose, the simultaneous use of SPOT-XS and VGT makes it possible to estimate daily reflectances of individual land coverages at the parcel level: SPOTXS is used to provide spatial information, i.e. the location of parcels, while VGT provides temporal information at a coarse spatial scale. The estimation of agricultural parameters for large areas is achieved through operational scenarios, which depend on the amount of data available. In this chapter, we detail one scenario, making use of one SPOT image and a VGT sequence to obtain land use at high spatial resolution together with its temporal behaviour