山体控制区拓扑分析的山顶点提取方法

Mountain Peak Extraction Based on Topological Analysis of Mountain Control Area

山顶点是一个容易意会却难以量化的地理特征。从山体地貌的认知着眼,对不同类型山体的山顶点控制区域进行分析,研究山顶点的高程、控制区的高差阈值、山体面积及平均坡度等山体地形特征的量化分析方法;在此基础上建立基于闭合等高线树山顶点控制区分析模型;并对山体地形特征进行量化表达,形成以山体控制区为约束条件的规格格网DEM数据的山顶点提取方法。使用1∶25万的祁连山DEM数据对新方法进行实验验证,提取准确率为96.8%。为验证新方法的普适性,选取极高山、高山、中山、低山等山体的DEM数据进行实验,山顶点提取结果理想,准确率较高,说明该方法适用于多种山体类型。

Mountain peak is geographical feature that is well understood but difficult to quantify expression. Focus on the cognition of mountain landform,the control area of the mountain peak was analyzed,and the quantitative analysis method of the mountain topographic features such as the elevation of the mountain peak,the height difference threshold,the mountain area and the average slope of the mountain were studied in this paper. On this basis,the analysis model of the peak control area based on the closed contour tree was proposed. At the same time,a quantitative expression model of mountain terrain features was established. At last,the extraction method of constraining control area in standard grid DEM data was developed. In order to verify the effectiveness of the new method,the experiment is carried out using 1 ∶ 250 000 scale Qilian Mountain DEM data. Peak extraction accuracy rate is 96.8%. Then different DEM data of height mountain ranging from 7 230 meters to 850 meters are chosen to verify the universality of the new method. It demonstrates that this method is efficient,accurate and applicable to a variety of mountain types.