sugarcane irrigation scheduling by combining remote sensing data and swap model in mirza-kuchak-khan sugarcane agro-industry, ahwaz, iran

irrigation scheduling means applying the right amount of water at the right time. in this research, thecurrent irrigation scheduling implemented in the mirza-kuchak-khan sugarcane agro-industry farmslocated in ahwaz was compared with the actual sugarcane crop water requirement using swapmodel. due to lack of field measured data, the swap model was calibrated and evaluated usinglandsat 7 etm+ images taken over the study area at twelve different dates during the sugarcanegrowing season. according to the results simulated by the swap model, the seasonal irrigation depthapplied (2640 mm) was much more than that required by the crop and, as a result, a significantamount of irrigation water was wasted in the form of deep percolation. the water productivity wasestimated to be 0.35 ton/ha.cm. in order to decrease deep percolation and improve water productivity,six irrigation plans including the possibility to reduce irrigation depth or eliminate some irrigationevents, or change irrigation times were evaluated by the swap model. for every plan studied, animproved irrigation scheduling was suggested. according to the swap simulations, implementationsof the suggested irrigation scheduling by eliminating some irrigation events or changing irrigationtimes can reduce seasonal irrigation depth by 27% and improve the water productivity by 30%.reducing irrigation depth by 20% can also increase the water productivity by 26%. in case bothscenarios mentioned can be applied together, the irrigation depth would decrease 42% and waterproductivity would increase 68%.