顾及各向异性的三维克里金空间插值

Research on 3D Interpolation Approaches Based on Kriging with Anisotropic Spatial Structures

针对三维空间插值各向异性与属性变化难以结合的问题,提出了一种以地统计学为基础,实现对具有各向异性地理现象的三维空间插值方法。首先,利用分层采样的方法收集青海湖周边土壤钾含量值,并进行采样优化;然后,采用主成分分析(Principal Component Analysis,PCA)对采样数据进行属性变化的方向特征分析,提取属性的特征方向;接着,进行结构特征分析,拟合三个轴上的变异函数曲线,构建各向异性变异函数的统一套合模型,获得土壤钾含量的三维空间插值结果;最后,与局部径向基函数(Local radial basis function, LRBF)和三维普通克里金(3D ordinary kriging, 3D-OK)方法比较,这种方法对地理属性进行结构特征分析,拟合变异曲线,能够反映地理现象在三维空间中的各向异性特征,从而规范构建三维变异函数的统一套合模型,且插值精度高,是一种可行的顾及各向异性三维空间插值方法。

It is difficult to combine the anisotropy with the change of attributes in 3 D spatial interpolation,a three-dimensional interpolation method based on geo-statistics is proposed to realize anisotropic geographic phenomena.Firstly,using stratified sampling method to collect soil potassium content values around Qinghai Lake,and sampling optimization;Secondly,the principal component analysis(PCA)is used to analyze the direction characteristics of the attributes of the collected data,and the feature direction of the data attributes is extracted;Then,the structural characteristic analysis was carried out,and the variogram curves of three axes were fitted.The unified model of anisotropic variogram was constructed,and the three-dimensional interpolation results of soil potassium content were obtained;Finally,compared with the local RBF and 3 D ordinary Kriging method(OK),this method analyzes the structural characteristics of geographical attributes and fitting the variation curve,which can reflect the anisotropic characteristics of geographical phenomena in three-dimensional space,and thus standardize the construction of three-dimensional variation function unified nested model,moreover,the interpolation results are higher accuracy,and it is a feasible interpolation method considering anisotropic 3 D space.