Optimizing soil water and salt environment is a key link to improving crop growth and achieving sustainable agricultural development. In this study, the response of controlled irrigation combined with aluminum sulfate to soil water, salt, and sugar beet growth was systematically investigated by combining the remote sensing image of the Jilin-1 satellite and the Hydrus-WOFOST coupling model. The results showed that controlled irrigation combined with aluminum sulfate could effectively improve soil structure, promote salt leaching and migration, enhance the water-holding capacity of the 0–50 cm soil layer, maintain soil water content at 18.5–23.5%, and control soil salt content at 1.26–1.43 g/kg. The leaf area index (LAI) and yield of sugar beet were significantly affected by soil water and salt coupling. Among them, the W 2 S 3 treatment (irrigation amount: 270 m 3 /ha, aluminum sulfate: 90 g/m 2 ) had the best effect, with LAI increasing by 19.42% and yield increasing by 30.84%. The ensemble Kalman filter (EnKF) is introduced to further improve the simulation accuracy of deep soil water and salt (R 2 is greater than 0.85), and realize the expansion from the field point scale to the regional scale. Combined with the BP neural network, the suitable application ratios were screened: irrigation amount, 278.96–285.31 m 3 /ha, and aluminum sulfate, 86.78–109.04 g/m 2 . This study has significant application value in saline-alkali land improvement and crop precision management, providing theoretical support and a technical path for realizing efficient agricultural water use and effective saline-alkali land management.
Chen et al. (Tue,) studied this question.