Validation of Bayesian Kriging of Arsenic, Chromium, Lead, and Mercury Surface Soil Concentrations Based on Internode Sampling
Validation of Bayesian Kriging of Arsenic, Chromium, Lead, and Mercury Surface Soil Concentrations Based on Internode Sampling
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DOI：
10.1021/es803322w
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发表时间：
2009-06-15
影响因子：
11.4
通讯作者：
McDermott, S.
中科院分区：
文献类型：
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作者：
Aelion, C. M.;Davis, H. T.;McDermott, S.
贝叶斯克里金法是估算金属空间分布的有用工具;然而，估算值通常仅在统计学上得到验证。在这项研究中，表层土壤样品收集在一个统一的网格和分析的As，Cr，Pb和Hg。数据通过贝叶斯克里金法在各个位置进行插值。使用留一交叉验证（LOOCV）统计方法对估计值进行验证，该方法比较了测量值和LOOCV预测值。验证也进行了使用额外的现场采样的土壤金属浓度之间的原始采样位置，这是比较克里格预测分布点。LOOCV结果表明，贝叶斯克里金是一个很好的预测金属浓度。当测量节间金属浓度和估计克里格值进行比较，测量值位于第5 - 95百分位数的预测分布在超过一半的节间位置。估计和测量的节间浓度是最相似的As和Pb。克里格估计值没有比较，以及低于分析最低检测限的浓度或非常接近原始采样节点的节间样品的测量值。尽管土壤中金属浓度存在固有的变异性，但克里格估计值在统计学上和现场测量中得到了验证
Bayesian kriging is a useful tool for estimating spatial distributions of metals; however, estimates are generally only verified statistically. In this study surface soil samples were collected on a uniform grid and analyzed for As, Cr, Pb, and Hg. The data were interpolated at individual locations by Bayesian kriging. Estimates were validated using a leave-one-out cross validation (LOOCV) statistical method which compared the measured and LOOCV predicted values. Validation also was carried out using additional field sampling of soil metal concentrations at points between original sampling locations, which were compared to kriging prediction distributions. LOOCV results suggest that Bayesian kriging was a good predictor of metal concentrations. When measured internode metal concentrations and estimated kriged values were compared, the measured values were located within the 5th-95th percentile prediction distributions in over half of the internode locations. Estimated and measured internode concentrations were most similar for As and Pb. Kriged estimates did not compare as well to measured values for concentrations below the analytical minimum detection limit or for internode samples that were very close to the original sampling node. Despite inherent variability in metal concentrations in soils, the kriged estimates were validated statistically and by in situ measurement