Study Of Coastal Wetland Resources Remote Sensing Survey And Thematic Mapping

Coastal wetlands investigation around ZhuHai city supported by remote sensing , GIS and GPS, using SPOT-5 data was studied in this paper, and the methods and accuracy of wetlands classification by remote sensing and thematic mapping technology were discussed.The study indicates that the classification effect on either supervised classification or unsupervised classification for wetlands classification with the SPOT-5 image is not satisfied. Otherwise, the method combining with computer classification and visual interpretation is the better to get wetlands information from SPOT-5 image. Furthermore, a complete set of wetlands remote sensing thematic mapping flow was summed up in this paper. The main content of this study is summed up as follows:1. Field investigation was conducted in the study area. The interpretation signs and wetland classification system were established.2. The 4,1,2 bands were selected for wetlands classification by spectral analysis of SPOT-5 images, enhanced the accuracy of remote sensing classification.3. The multi-spot image and panchromatic spot image are fusioned by using PCI PANSHARP latest remote sensing software integration algorithm .4. Image preprocessing,visual interpretation , unsupervised classification,supervised classification were conducted and the results of classifications were compared and the accuracies were evaluated.5. The space database of wetlands thematic data of the study area was established and thematic maps were produced .Also the new method to automatic extractting axis lines from polygon elements was discussed in this paper.