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首页> 外文期刊>Soil Science Society of America Journal >Evaluation of the Rawls et al. (1982) Pedotransfer Functions for their Applicability at the U.S. National Scale
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Evaluation of the Rawls et al. (1982) Pedotransfer Functions for their Applicability at the U.S. National Scale

机译：罗尔斯等人的评价。 （1982）Pedotransfer函数在美国国家范围内的适用性

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摘要

Large scale environmental impact studies typically involve the use of simulation models and require a variety of inputs, some of which may need to be estimated when adequate measured data are absent. As an example, soil water retention needs to be estimated for a large number of soils that are to be used in the context of the U.S. national scale Conservation Effects Assessment Project (CEAP). Use of a set of well known linear regression based pedotransfer functions (PTFs) developed in 1982 was proposed to address such data need. Examination of the underlying data as well as comparative estimations to an independent US-wide data set revealed that the proposed equations were most likely meant to use organic carbon (OC) data in place of the reported organic matter (OM) data. Other discrepancies-possibly due to misreporting-were also found in a large portion of the OM data. These PTFs were also developed from data originating from only 18 U.S. states-and 48% of them dominated by 3 U.S. states-while major cropland states/regions were barely or not represented at all. Resulting estimations showed non-random distribution of estimation residuals (i.e., bias) that could however be corrected with data transformations and by using a k-Nearest Neighbor algorithm as an alternative PTF technique. We recommend that the PTF equations proposed in 1982 not be used in the context of the U.S. national scale CEAP project. Alternative solutions should ensure the proper representation of U.S. soils and their properties.
机译：大规模环境影响研究通常涉及使用仿真模型，并且需要各种输入，而当缺少足够的测量数据时，可能需要估计其中的一些输入。例如，在美国国家规模的保护效应评估项目（CEAP）的背景下，需要估计大量土壤的土壤保水率。提出使用1982年开发的一组众所周知的基于线性回归的pedotransfer函数（PTF）来解决此类数据需求。对基础数据以及对一个独立的美国范围内的数据集的比较估计表明，所提出的方程式最有可能意在使用有机碳（OC）数据代替所报告的有机物（OM）数据。在大部分OM数据中也发现了其他差异（可能是由于误报所致）。这些PTF也是根据仅来自美国18个州的数据开发的，其中48％由美国3个州控制，而主要耕地州/地区则几乎没有或根本没有代表。所得的估计值显示出估计值残差（即偏差）的非随机分布，但是可以通过数据转换以及使用k最近邻算法作为替代PTF技术进行校正。我们建议不要在美国国家规模的CEAP项目中使用1982年提出的PTF方程。替代解决方案应确保正确表示美国土壤及其特性。

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