基于地统计学和遥感的岩溶区石漠化空间变异特征

Spatial variability of karst rock desertification based on geostatistics and remote sensing

为了全面掌握岩溶区石漠化的空间分布特征,解决区域内遥感影像阴影区域石漠化信息"缺失"的问题,该文以广西平果县果化镇生态重建示范区为例,借助图像处理软件ENVI(environment for visualizing images)提取研究区域石漠化指数。在GIS技术支持下,利用地统计学的方法对剔除阴影区后的石漠化指数进行了空间变异特征分析。结果表明,研究区域石漠化指数主要受内在因子的共同作用,具有强烈的空间自相关性;Kriging插值结果表明,研究区域石漠化指数较高的区域主要分布在研究区的西南部和东北部,各石漠化等级的空间分布表现为条带状和斑块状分布。岩性和地形地貌条件是影响石漠化空间变异的主要因素。研究利用地统计学的方法很好地估计了阴影区石漠化指数的"缺失"信息,为岩溶区石漠化监控、评估提供了新的思路与方法。

In order to master the spatial variability of karst rock desertification, and solve the problem of the shadow ＂missing＂ information of remote sensing images existing in the karst area,rock desertification indices were extracted in Guohua Ecological Experimental Area,which was in Pingguo county of Guangxi province by applying image processing software of ENVI（environment for visualizing images）. And the rock desertification indices of the shadow areas were excluded with the remote sensing images, then their spatial distribution were analyzed with geostatistical method. The results indicated that the rock desertification indices of the study area were impacted intrinsic factors and performed strong spatia1 autocorrelation. The spatial distribution maps of the rock desertification indices interpolated by Kriging interpolation method showed that the higher indices emerged in the northeast and southwest of the study area, and the spatial distribution of the karst rock desertification was apparently strip and block. The spatial distribution of the rock desertification levels in the study area is chiefly controlled by lithology and topography. Using geostatistical methods to predict the shadow ＂missing＂ information can provide a new idea and method for monitoring and evaluation of the karst rock desertification.