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1.
喀斯特地区春季土壤水分空间插值方法对比 总被引：1，自引：0，他引：1
以杨眉河小流域为研究区,通过土壤水分采样,选取辅助变量,采用普通克里金、协同克里金、回归克里金3种地统计学方法对土壤水分数据进行空间插值。结果表明：1）回归克里金对研究区土壤水分估算误差最小,其次为协克里金,普通克里金的误差最大;2）普通克里金生成的土壤水分表面最为平滑,而回归克里金最大程度反映了研究区实际的土壤水分空间变化;3）对于协同克里金,以湿度指数（WI）样点数据作为辅助变量的估算误差小于将WI栅格数据作为辅助变量的估算误差。总之,在可获得有效辅助变量的条件下,回归克里金对研究区土壤水分估算的效果优于协同克里金与普通克里金。 相似文献
2.
空间软数据及其插值方法研究进展 总被引：7，自引：0，他引：7
由于对地观测技术的迅速发展,空间数据的种类和数量增长迅猛,由空间数据反演得到的各种信息日趋膨胀,这些反演结果中的信息不少以软数据的形式出现。在实际应用中,这些软数据往往与空间插值的目标变量具有一定的相关性,甚至成为控制目标变量空间分布特征的重要因素。然而,由于这些数据通常表示为非数值形式,在计算和处理上存在着一定困难,以致被传统的插值方法所忽视,从而造成信息浪费。近来出现的空间软插值方法是一种利用空间软数据作为辅助信息并以改善插值效果的方法,能够较好的处理并利用软数据所隐含的信息,具有较好的应用发展前景。本文根据空间软数据的特点及其分类,系统综述了空间软插值方法及其应用领域。首先分析了空间数据软硬性质的根本区别,论述了软数据的分类和“硬化”方法,然后介绍空间插值模型中对空间软数据的集成方法和原理,最后对空间软插值方法及其应用研究领域进行了展望。 相似文献
3.
Climate spatial variability and data resolution in a semi-arid watershed, south-eastern Arizona 总被引：2，自引：0，他引：2
Susan M. Skirvin Stuart E. Marsh Mitchel P. McClaran David M. Meko 《Journal of Arid Environments》2003,54(4):667-686
In the 10,000 km2 San Pedro River watershed area in south-eastern Arizona, high-resolution spatial patterns of long-term precipitation and temperature were better reproduced by kriging climate data with elevation as external drift (KED) than by multiple linear regression on station location and elevation as judged by the spatial distribution of interpolation error. Mean errors were similar overall, and interpolation accuracy for both methods increased with increasing correlation between climate variables and elevation. Uncertainty in station locations had negligible effect on mean estimation error, although error for individual stations varied as much as 27%. Our future ability to examine spatial aspects of climate change at high spatial resolution will be severely limited by continuing closures of climate stations in this part of the United States. 相似文献
4.
Spatial interpolation of marine environment data using P-MSN 总被引：1，自引：0，他引：1
Bingbo Gao Maogui Hu Chengdong Xu Ziyue Chen Haimei Fan 《International journal of geographical information science》2020,34(3):577-603
ABSTRACTWhen a marine study area is large, the environmental variables often present spatially stratified non-homogeneity, violating the spatial second-order stationary assumption. The stratified non-homogeneous surface can be divided into several stationary strata with different means or variances, but still with close relationships between neighboring strata. To give the best linear-unbiased estimator for those environmental variables, an interpolated version of the mean of the surface with stratified non-homogeneity (MSN) method called point mean of the surface with stratified non-homogeneity (P-MSN) was derived. P-MSN distinguishes the spatial mean and variogram in different strata and borrows information from neighboring strata to improve the interpolation precision near the strata boundary. This paper also introduces the implementation of this method, and its performance is demonstrated in two case studies, one using ocean color remote sensing data, and the other using marine environment monitoring data. The predictions of P-MSN were compared with ordinary kriging, stratified kriging, kriging with an external drift, and empirical Bayesian kriging, the most frequently used methods that can handle some extent of spatial non-homogeneity. The results illustrated that for spatially stratified non-homogeneous environmental variables, P-MSN outperforms other methods by simultaneously improving interpolation precision and avoiding artificially abrupt changes along the strata boundaries. 相似文献
5.
A treatise on the use of geostatistics for the characterization of nonrenewable resources 总被引：1，自引：0，他引：1
James R. Carr 《Natural Resources Research》1992,1(1):61-73
Five decades of geostatistical development are reviewed to summarize the state of the art for spatial interpolation vis-à-vis kriging or a form thereof. Although a search of the literature reveals a variety of kriging methods, there are but two infrastructures for geostatistical interpolation: simple cokriging, for estimating a single variable using two variables, and generalized cokriging, for estimating one or more variables using the same number of variables that are estimated. The many forms of kriging are varieties of these two interpolation infrastructures. This notion is emphasized to aid the selection of an appropriate interpolation model for a nonrenewable resource. These models are discussed, and literature for the models and for applicable software is cited. Additionally, all aspects of spatial interpolation are discussed, including the adequacy of spatial sampling, distribution characteristics of spatial samples, semivariograms, search parameters, and selection of interpolation models in conformance with spatial data characteristics. Finally, the relationship between interpolation and raster-based geographic information systems is emphasized. 相似文献
6.
中国土壤温度的空间插值方法比较 总被引：15，自引：1，他引：14
利用中国698个气象站点1971~2000年的地面气候资料,采用三种不同方法预测中国0cm、20cm和40cm深度年均土壤温度的空间分布,其中普通克里格和泛克里格法直接以年均土壤温度数据为源数据、回归克里格法以中国年均气温数据和中国DEM数据为源数据进行预测。预测结果的准确性通过平均绝对误差(MAE)和均方根误差(RMSE)值来评价。结果表明回归克里格法预测的MAE值和RMSE值均为最小,说明其预测结果的准确性最好、预测的极端误差也最小;其次为泛克里格法;普通克里格法预测的效果最差。回归克里格法预测结果由于采用了中国DEM数据进行修正,在空间特征表达方面能够更好地表达复杂地形地区的局部变异,其平滑效应明显小于泛克里格法和普通克里格法的预测结果。 相似文献
7.
利用不同方法估测土壤有机质及其对采样数的敏感性分析 总被引：7，自引：5，他引：2
用随机方法从262个采样点中抽取200个点作为已知有机质含量的数据集,将所有采样点的碱解氮作为辅助数据预测有机质的空间分布。利用有机质信息的普通克立格法的方差解释量和预测精度最低,而回归克立格法因在预测过程中加入了回归残差而使方差解释量最大、预测精度最高。为了分析采样数对不同方法预测精度的影响,从上述已知有机质含量的200个点中分别随机抽取40、80、120、160个点构成4个数据集,分别利用它们的有机质信息和不同方法预测了有机质的空间分布,结果表明:对于每个数据集,4种方法的预测精度顺序均为RGK>COK>RG>OK,线性回归法的预测精度随采样点的增加基本不变,而其它三种方法的预测精度却逐渐提高。 相似文献
8.
不同时间尺度、季节的气温数据表现出不同的空间平稳特征。为探讨分析空间平稳性对气温插值的影响规律,采用趋势线法对气温数据进行空间平稳性探索,并对比分析不同空间平稳性条件下,普通线性回归、普通克里格、回归克里格的气温插值精度及插值结果的空间分布特点。结果显示：冬季日均、月均气温与年均气温呈现空间非平稳,插值精度随时间序列的增长而提高,随着气温数据逐渐趋于稳定,精度提高的幅度逐渐下降;夏季日均、月均气温呈现空间平稳,随时间序列的增长,插值精度的提高并不显著;夏季日均气温各插值方法的插值精度普遍高于冬季日均气温。与普通克里格相比,回归克里格能有效提高空间非平稳数据的插值精度。时间序列的增长削弱了不同插值算法之间的插值精度差异和插值结果空间分布差异。 相似文献
9.
Michael Kuntz 《International journal of geographical information science》2014,28(9):1904-1921
Small-sized housing samples and price predictions at nonobserved locations require geostatistical approaches, particularly the kriging estimator. Nevertheless, geostatistics has thus far received little attention in real estate economics. The article’s objective is to empirically compare the prediction accuracy of univariate kriging variants, namely detrended kriging (DK) and universal kriging (UK), and multivariate extensions, including detrended cokriging (DCK) and universal cokriging (UCK). Both latter methods consider structural and neighborhood characteristics as auxiliary variables. While the price surfaces of DK and UK show nearly identical cross-validated accuracies, the cross-validation-based prediction accuracy of DCK and UCK differ in favor of the latter. If real estate agencies are faced with a univariate sample of property prices, either DK or UK can be used, while in the multivariate case, UCK is recommended, although numerically more complex. 相似文献
10.
Oktay Erten Mehmet Siddik Kizil Erkan Topal Lachlan McAndrew 《Natural Resources Research》2013,22(3):207-227
Tropical laterite-type bauxite deposits often pose a unique challenge for resource modelling and mine planning due to the extreme lateral variability at the base of the bauxite ore unit within the regolith profile. An economically viable drilling grid is often rather sparse for traditional prediction techniques to precisely account for the lateral variability in the lower contact of a bauxite ore unit. However, ground-penetrating radar (GPR) offers an inexpensive and rapid method for delineating laterite profiles by acquiring fine-scale data from the ground. These numerous data (secondary variable) can be merged with sparsely spaced borehole data (primary variable) through various statistical and geostatistical techniques, provided that there is a linear relation between the primary and secondary variables. Four prediction techniques, including standard linear regression, simple kriging with varying local means, co-located cokriging and kriging with an external drift, were used in this study to incorporate exhaustive GPR data in predictive estimation the base of a bauxite ore unit within a lateritic bauxite deposit in Australia. Cross-validation was used to assess the performance of each technique. The most robust estimates are produced using ordinary co-located cokriging in accordance with the cross-validation analysis. Comparison of the estimates against the actual mine floor indicates that the inclusion of ancillary GPR data substantially improves the quality of the estimates representing the bauxite base surface. 相似文献
11.
Katsuaki Koike Toshiaki Minta Shinya Ishizaka Michito Ohmi 《Natural Resources Research》1996,5(1):23-32
An application of a geotechnical database system for primary evaluation of ground-water resources in a sedimentary basin is proposed. The database consists of 1200 borehole logs including geologic columns,in situ test results, ground-water level, water quality data, and resistivity logs. The Kumamoto plain, situated in southwest Japan, is chosen as a study area. The evaluation process consists of two steps: (1) modeling of shapes of water-bearing strata, and (2) modeling of distribution of physical quantity which has some relationship with the porosity of those strata. In step (1), the shapes of upper and/or lower surface of the pyroclastic flow deposits and the andesitic lava were determined, whereas the three-dimensional distribution model of resistivity was constructed from resistivity logging data obtained from 100 boreholes and using the proposed interpolation method in the step (2). An empirical equation between the porosity and the resistivity of the lava was also identified. The integration of two types of model and the empirical equation contributed to an estimate of the total volume of the ground-water under the study area. 相似文献
12.
Quantitative assessment of mineral resources with an application to petroleum geology 总被引：2，自引：0，他引：2
The probability of occurrence of natural resources, such as petroleum deposits, can be assessed by a combination of multivariate statistical and geostatistical techniques. The area of study is partitioned into regions that are as homogeneous as possible internally while simultaneously as distinct as possible. Fisher's discriminant criterion is used to select geological variables that best distinguish productive from nonproductive localities, based on a sample of previously drilled exploratory wells. On the basis of these geological variables, each wildcat well is assigned to the production class (dry or producer in the two-class case) for which the Mahalanobis' distance from the observation to the class centroid is a minimum. Universal kriging is used to interpolate values of the Mahalanobis' distances to all locations not yet drilled. The probability that an undrilled locality belongs to the productive class can be found, using the kriging estimation variances to assess the probability of misclassification. Finally, Bayes' relationship can be used to determine the probability that an undrilled location will be a discovery, regardless of the production class in which it is placed. The method is illustrated with a study of oil prospects in the Lansing/Kansas City interval of western Kansas, using geological variables derived from well logs. 相似文献
13.
鉴于传统各向异性二维半变异函数各向同性化方法未充分考虑或无力精确描述其内部结构信息的缺陷,本研究通过引入线性广义尺度不变（GSI）模型,以DEM数据作为验证对象,对二维半变异函数各向异性结构信息进行多尺度建模,并采用旋转椭圆法、两步搜索作图法等方法对系统参数进行估计,最后以球状模型为例对理论半变异函数的估计精度,及其在空间数据插值中的应用效果进行对比研究。结果表明：各向异性普遍存在于地形数据的空间变异中,有证据表明,这种各向异性结构中处处显现出不同的变形特征,但是也存在着某种规则性的成分,如各向同性圆形或近圆形等值线,因此,在对坐标进行各向同性化处理时不适合采用“一刀切”的方式去处理;GSI系统参数皆能得到较高精度的估计,如决定系数R2普遍达到了0.99以上,间接证明了GSI模型对地形数据各向异性结构处理的有效性和适用性;通过理论模型估计和插值结果对比,线性GSI坐标转换法比传统坐标转换法有了明显的精度提升,并且展现出了较高的边缘信息恢复能力,但也表现出了一定的局限性和不稳定性。 相似文献
14.
Several alternative estimation and interpolation methods for making annual precipitation maps of Asturias are analysed. The
data series in this study corresponds to the year 2003. There exists an evident relationship between precipitation and altitude,
with a high correlation coefficient of 0.70, that reflects the hillside effect; that is, the increase in the amount of precipitation
in more mountainous areas. The direct spatial variability of precipitation and of altitude and the cross variability of precipitation–altitude
are defined by two exponential variogram models: one with a short-range structure (15–30 km) that reflects the control exerted
by the lesser, local mountain ranges over the amount of precipitation; and another with a long-range structure (80 km) that
supposes the influence over precipitation of the major mountainous alignments of the inland areas of the Cantabrian Mountain
Range (Cordillera Cantábrica) situated between 60 and 90 km from the coastline. These variogram models had to be validated for coregionalization by the
Pardo-Igúzquiza and Dowd method so as to be able to make the cokriging map. The geometric estimation methods employed were
triangulation and inverse distance. The geostatistical estimation methods developed were simple kriging, ordinary kriging,
kriging with a trend model (universal kriging), lognormal kriging, and cokriging. In all of these methods, a 3 × 3 km2 grid was selected with a total of 2580 points to estimate, a circular search window of 60 km, and a relatively small number
of samples with the aim of highlighting the local features and variations on isohyet maps. The kriging methods were implemented
using the WinGslib software, incorporating two specific programs, Prog2 and Fichsurf, so as to be able then to make isohyet
maps using the Surfer software. All the methods employed, apart from triangulation, rendered realistic maps with good fits
to the values of the original data (precipitation) of the sample maps. The problem with triangulation lies not in the reliability
of the estimates but in the fact that it gives rise to contrived maps because of the tendency of isohyets to present abundant
triangular facets. The reliability of the methods was based on cross-validation analysis and on evaluation of the different
types of errors, both in their values and in their graphical representations. Substantial differences were not found in the
values of the errors that might discriminate some methods from others in an evident way. Bearing the aforesaid in mind, should
we have to make an evaluation of the different estimation methods in decreasing order of acceptance, this would be: kriging
with a trend model, inverse distance, cokriging, lognormal kriging, ordinary kriging, simple kriging, and triangulation. The
application of other estimation methods such as colocated cokriging, kriging with an external drift, and kriging of variable
local means (residual kriging) is dependent on the availability of a digital model of the terrain with an altitude grid of
the region. 相似文献
15.
Qin Zhen Wu Dong Luo Shaocheng Ma Xiugang Huang Ke Tian Fei Xiao Kun Chen Xiao Hou Min Pan Heping 《Natural Resources Research》2020,29(4):2619-2634
Fractured tight sandstone reservoirs are dual-pore systems including matrix pores and natural fractures, which both contribute to the system permeability. However, most previous studies either calculated the matrix permeability or obtained the fracture permeability to represent the system permeability in the logging evaluation of fractured tight sandstones because existing logging methods cannot distinguish the two types. In this study, a novel method is proposed to estimate the system permeability in fractured tight sandstones using geophysical logs. First, the fracture characteristics in the Upper Triassic Chang 8 member of the Yanchang Formation, southwest Ordos Basin, China, were analyzed. Based on the hydraulic flow unit approach, the formation classification criteria and the corresponding permeability–porosity models were established; then, the pure matrix permeability in the dual-pore system was calculated using geophysical logs. Based on the fracture characteristics, the relative pure fracture permeability was obtained using the Sibbit and Faivre method. By applying the Parsons’ model in boreholes, the system permeability was then calculated by coupling the relationship between the two permeabilities. Finally, two field applications in the study area demonstrate the feasibility of the proposed method, and the logging responses, application effects and applicable conditions of this method are discussed in detail. These applications indicate that the proposed method is suitable for tight reservoirs with fracture widths less than 200 μm, and considered to be dual-pore systems.
相似文献16.
利用Cokriging提高估算土壤盐离子浓度分布的精度——以黄河三角洲为例 总被引：10，自引：1，他引：9
估算土壤中化学物质的含量与空间分布是了解多孔介质中水盐运移规律并进而因地制宜地提出盐渍土改良措施的关键。大面积的实地采样分析费时费力且耗资巨大。通过地统计分析, 使用有限的采样数据可获得土壤溶质的准确变异。本文探讨和比较了Ordinary kriging (OK) 与Cokriging (COK) 这两种内插方法。结果显示一半的采样点数据的COK较之全部采样点数据的OK精度更高, 相对均方根误差降幅为130.83%;采用同样的协同变量 (239个全盐量数据), 一半的采样点数据的COK较之全部采样点数据的COK精度更高, 相对均方根误差降幅为20.10%。协同变量与主变量的相关度决定了COK的预测精度, 当相关系数由77%升高为99%时, 相对均方根误差降低了48.30%。 相似文献
17.
The Capanema Mine, an iron ore deposit, is located in the central portion of the Quadrilátero Ferrífero, State of Minas Gerais, southeastern Brazil. Mine development data from approximately 7000 drillholes were used for a comparative study between kriging variance and interpolation variance as uncertainty measurements associated with ordinary kriging estimates. As known, the traditional kriging variance does not depend on local data and, therefore, does not measure the actual dispersion of data. On the other hand, the interpolation variance measures adequately the local dispersion of data used for an ordinary kriging estimate. This paper presents an application of the concept of interpolation variance for measuring uncertainties associated with ordinary kriging estimates of Fe and silica grades. These data were selected for their distinct statistical characteristics with Fe presenting a negatively skewed distribution and, consequently, a low dispersion, and silica a positively skewed distribution and, therefore, a high variability. Comparative studies between the two uncertainty measurements associated with ordinary kriging estimates of Fe and silica proved the superiority of the interpolation variance as a reliable and precise alternative to the kriging variance. 相似文献
18.
癌症已成为危害全球居民健康的重大民生问题,选取合适的空间插值方法分析小区域癌症数据的空间特征可对区域性癌症防控工作的有效开展提供依据。本研究以湖南省苏仙区2012和2016年以村为单位的肺癌死亡率数据为研究对象,以平均误差和均方根误差为评价指标,对反距离加权（IDW）、普通克里金（OK）、趋势面分析（TSA）、多元线性回归（MLR）与协同克里金（CK）五种典型空间插值方法进行精度效果对比及参数优选,并结合不同插值方法的优缺点,确定癌症数据的最优插值方法。结果表明：插值精度方面,CK法的均方根误差最小、插值精度最高,OK、IDW（幂值=1）和MLR次之,TSA（阶数=5）最低;插值效果方面,五种插值方法的实测值和预测值均显著相关,除CK外,其它四种方法均对死亡率低估程度较大,CK和OK插值结果的空间分布效果更好。同时考虑空间因素和影响因子的CK方法是小区域苏仙区2012年、2016年肺癌死亡率最优插值方法,应用该方法可对区域性癌症防控工作的有效开展提供最优的技术支撑。本论文的研究思路也可为小区域癌症数据空间插值方法及参数优选提供参考。 相似文献
19.
C. H. Grohmann S. S. Steiner 《International journal of geographical information science》2013,27(8):895-906
The shuttle radar topography mission (SRTM), was flow on the space shuttle Endeavour in February 2000, with the objective of acquiring a digital elevation model of all land between 60° north latitude and 56° south latitude, using interferometric synthetic aperture radar (InSAR) techniques. The SRTM data are distributed at horizontal resolution of 1 arc‐second (～30 m) for areas within the USA and at 3 arc‐second (～90 m) resolution for the rest of the world. A resolution of 90 m can be considered suitable for the small or medium‐scale analysis, but it is too coarse for more detailed purposes. One alternative is to interpolate the SRTM data at a finer resolution; it will not increase the level of detail of the original digital elevation model (DEM), but it will lead to a surface where there is the coherence of angular properties (i.e. slope, aspect) between neighbouring pixels, which is an important characteristic when dealing with terrain analysis. This work intents to show how the proper adjustment of variogram and kriging parameters, namely the nugget effect and the maximum distance within which values are used in interpolation, can be set to achieve quality results on resampling SRTM data from 3” to 1”. We present for a test area in western USA, which includes different adjustment schemes (changes in nugget effect value and in the interpolation radius) and comparisons with the original 1” model of the area, with the national elevation dataset (NED) DEMs, and with other interpolation methods (splines and inverse distance weighted (IDW)). The basic concepts for using kriging to resample terrain data are: (i) working only with the immediate neighbourhood of the predicted point, due to the high spatial correlation of the topographic surface and omnidirectional behaviour of variogram in short distances; (ii) adding a very small random variation to the coordinates of the points prior to interpolation, to avoid punctual artifacts generated by predicted points with the same location than original data points and; (iii) using a small value of nugget effect, to avoid smoothing that can obliterate terrain features. Drainages derived from the surfaces interpolated by kriging and by splines have a good agreement with streams derived from the 1” NED, with correct identification of watersheds, even though a few differences occur in the positions of some rivers in flat areas. Although the 1” surfaces resampled by kriging and splines are very similar, we consider the results produced by kriging as superior, since the spline‐interpolated surface still presented some noise and linear artifacts, which were removed by kriging. 相似文献
20.
基于多元成土因素的土壤有机质空间分布分析 总被引：6，自引：0，他引：6
以陕西省蓝田县2013年667份土壤有机质样本为对象,运用GIS空间分析及遥感数字图像处理收集整理土壤类型、地形、植被等成土因子,利用多元线性回归分析集成所有成土因子对土壤养分进行空间分布预测。结果表明:通过分级统计均值定权法和像元线性拉伸法将所有成土因子统一为相对度量值,并根据成土因子与有机质含量的相关性显著程度进行因子取舍,有利于集成各类成土因子构建多元线性回归模型。预测结果定性分析表明:多元线性回归预测结果与kriging法预测结果在宏观上具有一致的空间分布趋势;但多元线性回归预测结果土壤有机质空间分布特征带有各种成土因子的变化特征,从视觉效果上,克服了传统插值法中存在的斑块状分布现象,更精细的描述了本区域内有机质空间分布趋势; MPE和RMS定量精度分析显示,在集成多元成土因素对有机质进行空间分布分析时,本文方法优于常用kriging插值法,该法可作为集成多元成土因子对土壤养分空间分布预测的有效方法。本区域内土壤有机质高值区域主要集中在地势低平、坡度缓和、湿度适中的农耕区,地势较高、坡度陡的山区有机质含量低。 相似文献