evaluated for other cases (crops, areas) as well, which eventually may result in a more generalized approach. 
Moreover, for operational applications of the combined use of optical and radar measurements, the translation 
to the use of spacebome data must be studied. The role of optical satellites like NOAA-AVHRR, Landsat-TM 
and SPOT must be evaluated in relation to the role of radar satellites like ERS-1 and JERS-1. 
6 - ACKNOWLEDGEMENTS 
This paper describes a study that was carried out in the framework of the NRSP-2 under responsibility of the 
Netherlands Remote Sensing Board (BCRS) and under contract no. 9837/92/NL/GS of ESA. Moreover, NASA 
and ESA are acknowledged for providing the AVIRIS and AIRSAR data in the framework of MAC Europe 1991. 
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