Simulation of water-salt transport and balance in cultivated-wasteland system based on SWAP model in Hetao Irrigation District of China

• Published in: Agricultural water management 2024-12, Vol.305, p.109132, Article 109132
• Main Author: Yuan, Chengfu
• Format: Article
• Language: English
• Subjects: agricultural land; autumn; China; Crop yield; Groundwater; irrigation scheduling; salinity; Salt flux; Soil salinity; soil salts; soil water; Soil water content; wastelands; Water flux; water table
• ISSN: 0378-3774
• DOI: 10.1016/j.agwat.2024.109132

Water and salt transport among different use type land is important to irrigation management in arid area. In this study, a typical irrigation unit including cultivated land and wasteland in Hetao Irrigation District of China was selected to explore water and salt transport between cultivated land and wasteland system. Soil water-salt dynamics, groundwater depth and salinity were observed within the period of crop growing and autumn irrigation period in 2018 and 2019. Calibrated SWAP model was used to simulate water and salt flux of cultivated land and wasteland during the crop growing period and autumn irrigation period. Furthermore, water-salt transport exchange capacity was calculated between cultivated land and wasteland system in study area. Groundwater was recharged by soil water and soil salt was leached in cultivated land during the crop growing period. Soil water was recharged by groundwater and soil salt was accumulated in saline wasteland during the crop growing period. During the crop growing period, the total leaching of soil salinity was 15.64 t·ha−1 in cultivated land. Soil salt accumulation was 2.03 t·ha−1 in saline wasteland. During the autumn irrigation period, the total leaching of soil salinity was 14.93 t·ha−1 in cultivated land. Total leaching of soil salinity was 1.56 t·ha−1 in saline wasteland. Overall, saline wasteland had an important role to receive salt from cultivated land and maintain salt dynamic balance in arid irrigation area with shallow groundwater. •Soil water-salt transport is complex and varying situation in cultivated-wasteland system.•SWAP model simulate water and salt flux in cultivated-wasteland system.•Calculating water-salt exchange capacity in cultivated-wasteland system.•Saline wasteland is drainage region for cultivated land in draining off water and salt.•Saline wasteland regulates water-salt balance and maintaining salt dynamic balance.