Simulation of Water and Salt Dynamics under Different Water-Saving Degrees Using the SAHYSMOD Model

Water shortage and soil salinization are the main issues threatening sustainable development of agriculture ecology in Hetao Irrigation District (HID). The application water-saving practices is required for agricultural development. However, further study to assess effects these on water salt dynamics long term. In this study, impacts different were investigated HID, Northwest China. SAHYSMOD (integrated spatial agro-hydro-salinity model) was used analyze irrigation scenarios. results indicate that model shows a good performance after successful calibration (2007–2012) validation (2013–2016). salinity cultivated land middle upper reaches district decreased slightly, while lower increased significantly over next 10 years under current drainage conditions. It predicted if amount diverted reduced by up 15%, maximum volume could reach 650 million m3 yr–1. For fixed reduction rate total diversion, prioritized measure should be given reduce field quota, then improve efficiency canal system. Although certain can saved through various measures, effect saving analyzed comprehensively, optimal management scheme determined considering ecological requirement HID.