The Extraction Of Geomorphologic Factors Based On Map Algebra

In the study of the relief, The geomorphologic factors plays an important role because it reflects the natural structure of the geomorphology of internal relatios. But the geomorphologic factors is precessed date rather than original data. In theory, DEM contain all the geomorphologic information, but in fact since the error aroused by the DEM accuracy and structure,translated algorithm and so on, The geomorphologic factors of the DEM is not idea. Ovrer the years it has been one of the basic issuess which constrainting the integrated geomorphology.In this paper, based on the DEM data sources of areas of Loess Plateau which in the north of Shaanxi Province,we used the map algebra theory and methods related, research and probe into a new way of extracting the geomorphologic factors . Due to the high-accurational DEM is a data basis of the extracting geomorphologic factors, we firstly introduces the methods of establishment of the DEM and the interpolated algorithms in common use, whose error and precision are analysed in the later. on this basis, Base on the map algebra we mainly studyed the DEM generation methods, finally we brought forward a method of establishing MADEM which is based on the map algebra.Then we mainly probed into the application value of using map algebra to extract geomorphologic factors, using the instances to proved the superiority and broad prospect of the new method. The algorithms we discussed all had been carried out on ArcGIS 9.1. At last, we discussed the precision and errrs of the extracted geomorphologic factors.As what the paper itself studying is one of the follow-up researches of the algebra map, the research result show that: the method of using algebra map to extract the geomorphologic factors does have a lot of advantages, which is worth being researched more thoroughly and widely. We also can drawn: currently the precision of extraction of the geomorphologic factors is really far from to meet the needs in reality. They have advantages and weakness clearly and there is big space to be improved.