Modeling the spatial distribution of soil properties by generalized least squares regression: Toward a general theory of spatial variates
Modeling the spatial distribution of soil properties by generalized least squares regression: Toward a general theory of spatial variates
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DOI：
10.2489/jswc.68.3.172
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发表时间：
2013-05-01
影响因子：
3.9
通讯作者：
Angulo-Martinez, M.
中科院分区：
文献类型：
--
作者：
Begueria, S.;Spanu, V.;Angulo-Martinez, M.
土壤特性的空间分布评估引起了土壤科学家的极大兴趣，既可以用于测试有关土壤形成过程的假设，也可以用于预测非采样位置的土壤特性（制图）。在本文中，我们讨论了空间变量建模的各种方法，并提出了一个建模框架，该框架能够合并空间变量中通常发现的最重要的效应，包括固定和随机空间效应、空间趋势和异方差。我们提供了一个案例研究，分析了西班牙比利牛斯山脉流域的八种土壤特性。作为解释性协变量，我们使用几个地形参数，这些参数可能与该地区活跃的成土过程相关。其中一些被证明对于解释土壤特性的变异性很有用，解释了高达 77% 的差异。我们关注模型选择的重要性，以确定哪些效应与每个土壤参数建模相关。我们发现完整的模型不一定对于所有测试的变量都是最优的，并且该模型应该适应每个个案的复杂性。本文对空间变量建模的讨论以及空间变量一般理论的最终发展做出了贡献。
Assessment of the spatial distribution of soil properties has achieved considerable interest among soil scientists, both for testing hypotheses about soil formation processes and for predicting the properties of soils at nonsampled locations (mapping). In this paper, we provide a discussion of the various approaches to the modeling of spatial variates, and we propose a modeling framework that is able to incorporate the most important effects usually found in spatial variates, including fixed and random spatial effects, spatial trends, and heteroscedasticity. We provide a case study of the analysis of eight soil properties in a mountain catchment in the Spanish Pyrenees. As explanatory covariates, we use several topography parameters, which can be related to the pedogenetic processes active in the area. Several of them proved useful for explaining the variability of soil properties, explaining up to 77% of their variance. We focus on the importance of model selection in order to determine which effects are relevant for modeling each soil parameter. We find that the full model is not necessarily optimal for all the variables tested and that the model should be adapted to the complexity of each individual case. This paper is a contribution to the discussion on the modeling of spatial variates and to the eventual development of a general theory of spatial variates.