Extraction of Hongze Lake Reclamation Area Based on RADARSAT SAR and LANDSAT ETM+

Due to some limitations of the visible and near infrared bands in remote sensing, radar remote sensing technology, which is capable in all-time, all-weather, and penetrating to some degree and so forth, has become a new technology and new method in rapid, large-scale information extraction. In this paper, the feasibility of using radar image as data source in terms of information extraction of Hongze Lake reclamation area is discussed. Firstly, based on RADARSAT-1 data, radar image was calibrated, geometrically corrected and filtered. Secondly, classification was carried out on SAR data and ETM+ data by using thresholds with the help of groundtruth data. Then, the ETM+ data was classified into the categories of aquaculture, open water, rice paddy and wetland vegetation by using wetness and spectral characteristics. Finally, the categories extracted from two different data sources were combined together. The results show that the methods used in this research are practical and efficient. The overall accuracy of classification is 93% with high Kappa Coefficient of 0.87.