الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Water productivity in agriculture needs to be raised to meet the increasing demand for food due to the increased population, especially in the scarce resource’s regions. AquaCrop simulates different agricultural-water management practices such as soil mulching and irrigation systems. Although soil temperature under mulching conditions has a significant impact on crop development and growth rate and other parameters. However, it is not included in the AquaCrop model. Besides that, the sub-surface drip (SSD) irrigation system simulation in the AquaCrop model did not consider the drip line depth and the capillary rise occurrence under the SSD Thus, the main objectives of this study are to i) improve AquaCrop model performance for better simulation of soil mulches by considering the heat changing under mulch materials. ii) develop SSD system considering the lateral depth and capillary rise. iii) investigate the impact of climate change under different emissions (RCP8.5 and RCP4.5) on yield, water productivity, and crop evapotranspiration, etc under two periods (2030s and 2040s). The proposed modification related to soil mulching simulation considered the differences between the temperatures under the mulch materials and air temperatures and described them as additional heat units in specific growth stages. Besides that, (SSD) system was developed considering the lateral depth effects water distribution and capillary rise. The modified AquaCrop model was verified and validated using experimental data of growing melon and tomato crops at Bari, Italy and Cairo, Egypt respectively. The verification was done using data of melon growth under different irrigation treatments (full irrigation, deficit irrigation and rain-fed watering regimes) and soil mulching practices (without mulching and black plastic mulch) while the validation has been done using tomato grown experiments under different mulching practices (without mulching, organic mulch, and black plastic mulch) and different irrigation systems (surface drip and sub -surface drip irrigation systems) plus, different irrigation schedules based on the original and the modified model. The performance of the modified model was better than the original model. The Root Mean Square Error (RMSE) was decreased by 40% to 75% in the verification process and by 72% to 84% in the validation process. Regarding the climate change impact assessments, the use of plastic mulch is considered the best practice in terms of water saving under climate change. Moreover, the CO2 concentration has a key role in changing the yield and water productivity.