Soil property data plays a crucial role in watershed hydrology and non-point source (H/NPS) modeling, but how to improve modeling accuracy with affordable soil samplings and the effects of sampling information on H/NPS modeling remains to be further explored. In this study, the number of sampling points and soil properties were optimized by the information entropy and the spatial interpolation method. Then the sampled properties were parameterized and the effects of different parameterization schemes on H/NPS modeling were tested using the Soil and Water Assessment Tool (SWAT). The results indicated that the required sampling points increased successively for soil bulk density (SOL_BD), soil saturated hydraulic conductivity (SOL_K) and soil available water capacity (SOL_AWC). Compared to the traditional database (Harmonized world soil database), the NSE and R performance by new scheme increased by 22.8% and 10.5%, respectively. The entropy-based optimization reduced the sampling points by 13.2%, indicating a more cost-effective scheme. Compared to hydrological simulation, sampled properties showed greater effects on NPS modeling, especially for nitrogen. This proposed method/framework can be generalized to other watersheds by upscaling field soil sampling information to the watershed scale, thus improving H/NPS simulation.

中文翻译：

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从田间土壤采样到流域模型：整合信息熵和插值方法进行升级


土壤属性数据在流域水文和面源（H/NPS）建模中发挥着至关重要的作用，但如何通过负担得起的土壤采样来提高建模精度以及采样信息对H/NPS建模的影响还有待进一步探讨。本研究通过信息熵和空间插值方法对采样点数量和土壤性质进行优化。然后对采样的属性进行参数化，并使用土壤和水评估工具 (SWAT) 测试不同参数化方案对 H/NPS 建模的影响。结果表明，土壤容重（SOL_BD）、土壤饱和导水率（SOL_K）和土壤有效水容量（SOL_AWC）所需采样点依次增加。与传统数据库（协调世界土壤数据库）相比，新方案的NSE和R性能分别提高了22.8%和10.5%。基于熵的优化减少了13.2%的采样点，是一种更具成本效益的方案。与水文模拟相比，采样特性对 NPS 建模的影响更大，尤其是氮。通过将现场土壤采样信息升级到流域规模，该方法/框架可以推广到其他流域，从而改进 H/NPS 模拟。