贵州洞穴空间格局及影响因素分析

Spatial pattern of the caves in Guizhou Province and their the influencing factors

以贵州水文地质图和地形图为基础,利用Arc GIS对境内近5000个洞穴洞口海拔、经纬度提取及所在地层、岩性、水系、构造划分,并运用最邻近指数、空间分析与耦合分析处理,研究了贵州全省4960个洞穴的分布特征,探讨了洞穴空间格局与地理要素之间的关系。通过对贵州洞穴进行点格局分析,得出最近邻指数为0.53,泰森多边形检验其变异系数达72.469%,符合凝聚分布模式;并采用点密度函数将全省洞穴划分为4个集聚区和1个弱影响区,即遵义—铜仁强影响区、毕节强影响区、黔西南—六盘水强影响区、贵阳—安顺—黔南强影响区和黔东南弱影响区。其中贵阳—安顺—黔南强影响区是洞穴最主要的分布区,占全省洞穴总量的36.63%,该影响区面积占全省面积的24.67%。贵州洞穴分布呈西密东疏的分布特征,形成明显的"片状"格局。在其研究背景下,地层、岩性、构造、气候、水文、海拔等因素主要制约洞穴的分布、数量、空间格局及其发育。

Based on the hydrogeological and topographic map of Guizhou Province, Arc GIS was used to extract the information of nearly 5000 caves in the province, including the altitude,latitude and longitude, the strata, lithology, water system, and structure division. The nearest neighbor index, spatial analysis and coupling analysis methods were used to examine the distribution of 4960 caves in Guizhou Province. The relationship between cave spatial pattern and geographical elements was discussed. Through the point pattern analysis of the caves, it is found that the nearest neighbor index is 0.53, and the variation coefficient is 72.469% tested by Thiessen polygons, which is consistent with the model of aggregate distribution. Through the dot density function method, all the caves were divided into 4 clusters, namely, Zunyi-Tongren strong influence area, Bijie strong influence area, Liupanshui-Qianxinan strong influence area,and Guiyang- Anshun- Qiannan strong influence area, and one weak influence area（Qiandongnan weak influence area）. Among them, Anshun- Qiannan- Guiyang strong influence area is the most important area, accounting for 36.63% of the total number of the caves, and24.67% of the total area of the province. The caves in Guizhou are concentrated in the west and sparsely distributed in the east, shwoing clear ＂flake＂-shaped pattern. Results indicated that the natural factors such as strata, lithology, structure, climate, hydrology, and elevation mainly affect the distribution, quantity, spatial pattern and development of the caves.