Approach And Application Of Topographic Slope Gradation Polygon Aggregation Based On SRTM

The DEM (Digital Elevation Model) is one of the main components of the GIS spatial database, and its application has been widely into many fields of mapping, remote sensing, environmental resources, agriculture or forestry land use planning, urban planning, disaster, and hydropower projects, military, etc. Digital Elevation Model, as the carrier of a variety of geographic information, which contains rich topography information and Geosciences knowledge, is the data basis of Geographic Information System digital terrain analysis. The emergence of SRTM (Shuttle Radar Topography Mission) technology changed the conventional way of data acquisition, and provides a large number of data sources for the research of the digital elevation model.Slope means the degree of surface tilt, topographic slope is the terrain surface tilt quantitative description. The slope has been one of the research focus of the Earth Science analysis. Therefore, the slope is first and foremost consideration of the terrain factor in research work of soil and water conservation, water conservancy, soil erosion, land use planning, natural disaster risk prediction, transportation construction, urban layout and planning. Slope gradation with different classification methods. The slope of the quantitative studies should also consider the Topographic Slope Gradation polygon aggregation. The aggregation of the polygon is also one of the main factors affect the application of slope classification map. There is no uniform procedure at this stage of the aggregation of the slope polygon method. And most of the aggregation approach to human-computer interaction. Therefore, there are a variety of slope polygons aggregate differences and the quality of the slope classification map is affected. And it leads to a negative slope classification map application.The paper analyzes the SRTM data of the Applied Research, and Digital Elevation Model data acquisition, construction method and Research. The terrain slope gradation experiment using raster resample and interpolation methods establishes the different experimental area30m resolution digital elevation models by SRTM data, and analyzes and judges suitability of the different interpolation methods.Based on30m resolution digital elevation model, select with reasonable calculation model of slope and classification method of slope; extract information of terrain slope and divide information of slope grade,then generate original slope gradation map. Studying with the aggregation of slope polygon rules and methods, and realize the slope polygon aggregation with adjacent map spot and nearby slope grade. That means low adjacent map spot aggregation to high adjacent map spot and high adjacent to low adjacent map spot,and two aggregation of principle be used in selecting and combination, and then make the choice of surplus map spot aggregation with nearby polygon, in the end realize the classification of slope polygon aggregation, optimize the slope classification map.