Study And Practice On Updating Landuse Base Data By Using RS Technology

The traditional technology of updating large-scale and middle-scale landuse basic map in our country is under-developed and there is great artificial disturbance. It cannot catch up the changing information and it is difficult to locate the changing space position of the cadastral parcels. The work takes a lot of time and a large amount of labor. In many areas, it is very difficult to upgrade the map in time each year.The appearance of commercial high-resolution satellite image makes it possible to update large-scale landuse map frequently. Basing on RS, the updating method of the basic landuse map is becoming one of the most important study direction in landuse and cover change field over the world.Combining remote sensing digital image manipulation technology with GPS technology, the thesis proposes a technical procedure to update the landuse base-map and landuse database from a practical angle. Consulting the cost performance of different satellite remote sensing data sources, the thesis provides reference for choice of methods of upgrading the map with all kinds of scales; provides a method of making landuse DRG and ortho-photo image; discusses in detail how to choose correcting method and merging method.There are two ways to find out the changed information. One is to detect automatically by comparing the base period RS image and the upgraded RS image. The other is by overlapping the RS image, the changed map-patches, and the landuse data. Supported by the GPS, the changed map-patches can be verified, and the scattered land sort and the missing map-patches supplemented. By converting GPS data into GIS data, it can import updated data into GIS system. Based on GIS, changed map-patches layers are modified and compiled, and the topology relations are built. The landuse map and landuse database are updated.As an application to Yangzhong city in Jiangsu Province, the method of updating landuse base map by remote sensing technology has been proved valid. The conclusion is that the new method is feasible and can be mastered easily, and its achievement is satisfactory. Compared with traditional methods, this method can reduce the workload greatly.