Exploration of strategies to improve irrigation management of alfalfa (Medicago sativa L.), berseem (Trifolium Alexandrinum L.) and silage maize (Zea mays L.) in Tadla – Morocco

Abstract

The CropSyst model, an operative crop model, is used to explore irrigation scenarios for the main folder crops in Tadla irrigated area in Morocco. The calibration and validation of CropSyst model have been realized previously for alfalfa, silage maize and berseem. The model was run for a 40 year simulation with climatic data measured daily; using several scenarios involving a combination of irrigation times and water amounts. For alfalfa, the results obtained indicate that applying 1600 mm of irrigation water amount maximizes irrigation water efficiency (1.21 kg/m3) and achieve a yield of 23.1 t/ha (95% of the yield potential). In the case of maize, application of 648 mm through 2 irrigations in initial phase, 2 irrigations in linear and two in final phases allows to achieve high biomass yield and better water use. On berseem, the simulation results confirm that the adoption of the scenario that provides 625 mm allows obtaining 14.1 t/ha of dry matter which represents 94% of the yield potential. Finally, the coupling of the results of four years (2008 - 2012) experimentations with the simulations of scenarios by CropSyst has shown to be highly effective in order to improve the folder crops irrigation in the Tadla