The soil water retention curve (SWRC) describes how much water can be retained and is available for plants in soil under different matric potentials. SWRC plays an essential role in the modeling of soil hydraulic processes and can be estimated with pedotransfer functions (PTFs). Splintex 2.0 is a PTF model developed with a user-friendly computer interface that can estimate soil hydraulic functions' parameters. As opposed to common PTFs that need to be calibrated using empirical data, Splintex 2.0 was based on a semi mechanistic model that translates particle-size distribution data into solid mass fractions and pore-size distribution. The objective in this work was to widely test the performance of Splintex 2.0 against the performance of its previous version (Splintex 1.0) using a database of 1355 samples from various countries. This large number of samples allowed a detailed quantification of the univariate and bivariate probability distributions of the estimated parameters in different hydrogeology, climate, and soil types. The accuracy of Splintex 2.0 was examined by means of linear correlation analysis (r) for random errors and of mean error (ME), mean absolute error (MAE), and root mean square error (RMSE) for systematic errors. The Splintex 2.0 model overcame the estimation’s discrepancy of SWRCs from its previous version and performed similarly with two other published PTF models. In particular, Splintex 2.0 performed as well as these published PTFs in estimating water content at field capacity over a wide range of soil types. In summary, because of its mechanistic nature, Splintex 2.0 can be an alternative model for estimating SWRC and field capacity in new areas where there is a lack of calibration data.

土壤保水曲线（SWRC）描述了可以保留多少水，以及在不同基质势下土壤中的植物可利用的水量。SWRC在土壤水力过程建模中起着至关重要的作用，并且可以用pedotransfer函数（PTF）进行估算。Splintex 2.0是使用用户友好的计算机界面开发的PTF模型，该界面可以估算土壤水力功能的参数。与需要使用经验数据进行校准的常见PTF相对，Splintex 2.0基于半机械模型，该模型将粒度分布数据转换为固体质量分数和孔径分布。这项工作的目的是使用来自不同国家的1355个样本的数据库，将Splintex 2.0的性能与其以前版本（Splintex 1.0）的性能进行广泛的测试。大量的样本可以对不同水文地质，气候和土壤类型中估计参数的单变量和双变量概率分布进行详细的量化。通过线性相关分析来检查Splintex 2.0的准确性（r）代表随机误差，均值误差（ME），平均绝对误差（MAE）和均方根误差（RMSE）代表系统误差。Splintex 2.0模型克服了SWRC与其先前版本的估计差异，并且与其他两个已发布的PTF模型具有相似的性能。特别是，Splintex 2.0在评估各种土壤类型的田间持水量时的性能与这些已发表的PTF一样出色。综上所述，由于其机械特性，Splintex 2.0可以作为一种替代模型，用于在缺乏校准数据的新区域中估算SWRC和现场容量。