5.Conclusions
Classification of land use/cover in the Bangladesh floodplain using RADARSAT F3 data was addressed in this study. For reducing speckle in SAR imagery, two filters, Gamma-map and Frost were tested and Frost filter was found better than Gamma-map filter for both crop and flood monitoring. The disadvantage of using the Frost filter was that it takes longer exaction time than the Gamma-map filter ( about 4 times more ). Therefore the Gamma-map filter would be more efficient for near real time flood monitoring.

The ground truth data, acquired at the time of satellite overpass, were used to evaluate the classification of the radar data. By comparison of the SAR classification and ground observation data, the overall accuracy of gamma-map and frost filtered dataset were 64% and 69% .

The study area has a complex heterogeneous land use/cover. As it was possible to classify this complex land use/cover, it is expected that other parts of the country, where less complexity in land use/cover found could also be classified using similar SAR images. Hence, this study has demonstrated the potential of using radar data in monsoon season as a floodplain land use/cover mapping tool.

The study period of 1998 was an excessive flooding year and a similar study to assess the potential of SAR data in an average flooding year could be useful. Such a study, combined with the result of this project, would provide firmer conclusions about the potential of using SAR to manage flooding dynamics in Bangladesh.

Acknowledgements
The F3 images from May'98 to August'98 were by RADARSAT International under the Application Development Research Opportunity (ADRO) Project NO 418. This study was a collaborative project of the Tan Gail Compartmentalization Pilot project (CPP), with EGIS. Both CPP and EGIS are project under Water Resources Planning Organization of Ministry of Water Resource of Bangladesh Government. EGIS is executed with funding from the Royal Netherlands and Bangladesh Government. The support from Ir. Rob Koudaastal, Team Leader, EGIS is highly appreciated RADARSAT data are projected under copyright by the Canadian Space Agency, received by Canada Centre for Sensing and pre-processed by RADARSAT International Inc.

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