基于GIS技术的茂兰喀斯特典型地貌提取与空间分布特征研究

Study on Extraction and Spatial Distribution Characteristics of Karst Geomorphology in Maolan based on GIS Technology

摘要: 茂兰保护区喀斯特地貌十分发育且形态丰富多样，以峰丛漏斗和峰丛洼地最为典型，为进一步探索该类类型地貌的空间规律和内部关系，加深典型地貌的理解和认识，以万分之一地形图为基础，矢量化得到数字高程模型，在ArcGis中利用工具提取地貌属性数据，根据划分原则确定地貌类型，采用Fisher判别法对分类的地貌结果进行验证，同时确定未定义的地貌类型，并建立判别方程。然后回传数据到ArcGis中修正数据，利用密度制图、3D分析等多种方法相结合，探讨了茂兰保护区典型地貌空间分布特征。其结果为：1) 基于Fisher判别分析法对典型地貌分类验证，正确率为91.9%，判别方程可用于对典型地貌进行有效分类。2) 典型地貌水平空间分布划分为高、中、低三个密度等级区域，其中，漏斗高密度为5.09个•km⁻²、中密度2.93个•km⁻²、低密度0.9个•km⁻²；洼地高密度为2.21个•km⁻²、中密度1.09个•km⁻²、低密度0.29个•km⁻²。3) 典型地貌在不同海拔上具有显著差异性表现。

Abstract: Manlan reserve karst landforms are well-developed and form rich variety, with peak cluster funnel and peak cluster depression is most typical, in order to further explore the types of the landscape space law and internal relations, deepening the understanding and awareness of the typical landforms, on the basis of one over ten thousand topographic maps, digital elevation model, vector quantization in ArcGis attribute data using tools to extract features. The geomorphic types were determined according to the classification principle. Fisher discriminant method was used to verify the classified geomorphic results, and the undefined geomorphic types were determined and the discriminant equation was established. Then, the data were returned to ArcGis to modify the data, and various methods such as density mapping and 3D analysis were used to discuss the spatial distribution characteristics of typical geomorphology in Maolan Reserve. The results were as follows: 1) Fisher discriminant analysis was used to verify the classification of typical landforms, and the accuracy was 91.9%. The discriminant equation could be used to effectively classify typical landforms. 2) The horizontal spatial distribution of typical geomorphology was divided into high, medium and low density regions, among which the density of funnel was 5.09•km⁻², the density of funnel was 2.93•km⁻² and the density of funnel was 0.9•km⁻². The high density, medium density and low density of the depression were 2.21•km⁻², 1.09•km⁻² and 0.29•km⁻² respectively. 3) There are significant differences in typical landforms at different elevations.