Reproducibility of the wet part of the soil water retention curve: a European interlaboratory comparison (dataset)

The soil water retention curve (SWRC) is a key soil property required for predicting basic hydrological processes. The SWRC is often obtained in the laboratory with non-harmonized methods. Moreover, procedures associated with each method are not standardized. This can induce a lack of reproducibility between laboratories using different methods and procedures or using the same methods with different procedures. The goal here was to estimate the inter- and intralaboratory variability of the measurement of the wet part (from 10 to 300 hPa) of the SWRC. An interlaboratory comparison was carried out between 14 laboratories, using artificially constructed, porous reference samples that were transferred between laboratories according to a statistical design. The retention measurements were modelled by a series of linear mixed models using a Bayesian approach. This allowed the detection of sample-to-sample variability, interlaboratory variability, intralaboratory variability and the effects of sample changes between measurements. Here we present the dataset containing measured data from the interlaboratory comparison, R code to implement models, and final model results.土壤水分特征曲线（Soil Water Retention Curve, SWRC）是预测基础水文过程所需的关键土壤物性参数。该曲线通常通过实验室非标准化方法获取，且各方法配套的操作流程亦未统一。这会导致采用不同方法与流程的实验室间，或使用相同方法但流程存在差异的实验室间，出现实验结果难以复现的问题。本研究旨在估算土壤水分特征曲线湿段（压力区间为10至300 hPa）测量结果的室间与室内变异程度。研究依托统计设计开展了14家实验室间的比对实验，使用人工制备的多孔参考样品按照实验设计在各实验室间流转。研究采用贝叶斯方法构建系列线性混合模型对持水率测量数据进行建模，借此可识别样品间变异、室间变异、室内变异以及两次测量间样品变化带来的影响。本数据集包含本次实验室间比对的实测数据、模型实现所用的R代码以及最终模型结果。