Research On Digital Geomorphologic Mapping Based On RS And DEM Of Tonle Sap Area Cambodia

The paper focus on the work of finding mineral in the area of The Tonle Sap, Cambodia, starting on landform research, nailing down the landform type of possible existent placer and its distribution, picking up the configuration and modality of landform type, and protracting landform information graphs. According to the landform type in the area of the Tonle Sap, Cambodia, we try to mainly accumulate fluvial landform characteristics of landform and fluvial corrosive landform. So we can start on the research of landform and micro-landform charting to carry out digital landform charting based on the remote sensing image of pixel by using TM, ALOS data and SRTM DEM data.We used the TM image data, we directly select pixel spectrum, monitoring and classifying surface cover by methods of Spectral Angle Mapper and Maximum likelihood. For ALOS image data, we select Vegetation index RVI,DVI,TSAVI and DEM data participate in unsupervised classification finished the classification of land-cover and built a basis for digital landform charting.Using digital terrain analysis technique to realize the extraction of tenain, based on SRTM DEM. During the process of the terrain factor extracting, by the using of the image segmentation function of the German software eCognition, take the light projection or segmentation of remote sensing images obtained polygon vector data instead of the traditional grid as Statistics. Modify traditional ups and downs of the tenain, with an average elevation, the average slope of tenain, and other methods of calculation. Aiming at Sap Lake area for the accumulation of special landscape environment, the first use of anti-SRTM DEM data to extract water from the method and achieved very good results. Analyze the results of the research, and choose the appropriate classification of images and thematic maps participation in the digital landscape mapping, and object-oriented image classification technology into digital mapping of the landscape. Use remote sensing images from micro-topography and landscape, and take DEM as a component of remote sensing images, pixel-based classification of remote sensing imagery, tenain of thematic maps such as joint participation image segmentation and classification, and eventually realize the types of landscapes and figures landscape mapping, obtain topography, micro-topography thematic map.The results of the research and the innovative points:1. The vector polygon data which obtains by the illumination projection or the remote sensing phantom division will replace traditional the graticule mesh to take the statistical scope, may enhance the tenain factor obviously to the tenain expressive force, and maintained the landform boundary and the actual surface tallies the nature.2. The remote sensing data with DEM conelation images, such as stretched DEM, average elevation chart, tenain prominency chart together fellowship the image classification. This mehod help the researchers can giving consideration to the elevation Information when they do the remote sensing image classification.The result of the classification has a good classifying quality, with less mistakes, more recognized kinds.The taxonomic boundary line get in this way with the diversity of land-cover and terrainfactor.3. Introducing the object-oriented remote sensing image classification method into the cartography of geomorphology classification,the method can helping clearing the isolated points, protruding points, and removaling the influence of salt and pepper noise.