Experimental and numerical evaluation of soil water and salt dynamics in a corn field with shallow saline groundwater and crop-season drip and autumn post-harvest irrigations

作者：Shuhao Guo, Xianyue Li, Jiřı́ Šimůnek, Jun Wang, Yuehong Zhang, Yanan Wang, Zhixin Zhen, Rui He · 发表于：Agricultural Water Management · 年份：2024 · DOI：10.1016/j.agwat.2024.109119 · 被引用次数：17 · 研究领域：Soil and Unsaturated Flow、Soil Moisture and Remote Sensing、Irrigation Practices and Water Management

In areas with shallow saline groundwater, soil salts inevitably accumulate in the root zone during the growth period due to irrigation and upward movement of salts from the groundwater. In Northern China, autumn irrigation (AIR) with large amounts of water is commonly employed post-harvest to mitigate soil salt stress on crop growth in the subsequent year. Optimizing the total irrigation depth during both crop-growth and non-growth periods is challenging because of the movement of soil salts, which is influenced by their two-dimensional distribution around drippers and the impact of the winter freeze-thaw cycles, significantly affecting water flow and solute transport during winter. In this study, the HYDRUS-1D and HYDRUS-2D models were integrated and calibrated using experimental data collected from 2021 to 2023 in China's Ordos south bank irrigation area. This model integration was conducted to assess soil water and salt dynamics during the non-growth and corn-growth periods under different irrigation strategies: a) AIR with high (A H ) and low (A L ) irrigation depths, and b) drip irrigation (DIR) with high (D H ), medium (D M ), and low (D L ) irrigation depths. The results indicated that HYDRUS effectively modeled the electrical conductivity of the saturation paste extract ( EC e ) across different irrigation strategies, yielding an average coefficient of determination ( R 2 ) and the root mean square errors (RMSE) of 0.87 and 0.53 dS m −1 , respectively. Generally, EC e...