Experimental Study on Crop Coefficient under Mulched Drip Irrigation in Hetao Irrigation District of Inner Mongolia

Through the field experiments,crop coefficients were calibrated under mulched drip irrigation based on Penman-Monteith equation and the water balance method,and the irrigation scheduling was studied.Results indicated that crop coefficients of maize were 0.162,0.718,1.251 and 0.409 while crop coefficients of sunflower were 0.194,0.779,1.26 and 0.315 in the early growth stage,rapid growth stage,mid-growth stage and mature stage under mulched drip irrigation,respectively.The water consumptions of maize and sunflower in the whole growth stage were 445 and 340mm under mulched drip irrigation,which decreased by 12.7%and 4.5%compared to traditional irrigation,respectively.