Modelling of moisture movement and irrigation scheduling in drip irrigated tomato using CROPWAT and HYDRUS-1D

Abstract

The irrigation systems require modernization and management by evaluating water system prerequisites precisely. A study was carried out at Srinagar during kharif 2022 to determine the crop water demands, irrigation scheduling and simulation of moisture movement under different irrigation regimes on tomato crop in open field conditions using CROPWAT and HYDRUS-1D models. The results revealed that the average crop water requirement at 100% ETC per plant per day was 0.24 l plant-1 day-1 during the initial stage, 0.37 l plant-1 day-1 during development stage, 0.85 l plant-1 day-1 during mid-stage and 0.74 l plant-1 day-1 during the end stage. Soil water content was simulated by HYDRUS-1D model in 0 to 30 cm of soil profile. Higher values (0.86 to 0.95) of coefficient of determination (R2) indicated that observed and simulated values of moisture content are highly correlated and the model predicts that lower values of mean absolute error (MAE) and root mean square error (RMSE) indicates that the HYDRUS-1D model is more accurate at simulating the movement of moisture under different irrigation regimes.

Keywords

• Crop water requirement
• CROPWAT
• HYDRUS-1D
• Irrigation scheduling
• Reference evapotranspiration
• Simulation