Influence of evapotranspiration assessment on the accuracy of moisture transport modeling under the conditions of sprinkling irrigation in the south of Ukraine

The paper presents the results of computational experiments for evaluating the impact of different evapotranspiration assessment methods usage on the accuracy of soil moisture dynamics simulation for the conditions of sprinkling irrigation. We consider a differential one-dimensional model of moisture transport stated in terms of water head which uses as an initial data the estimates of evapotranspiration according to the methods of Ivanov, Shtoiko, Penman-Monteith and SEBAL. The differential moisture transport model was discretized using the finite-difference scheme. Its unknown parameters values were found by solving an inverse problem using the metaheuristic particle swarm optimization algorithm. We perform water head modeling accuracy assessment using different methods of evapotranspiration evaluation along with their linear combination. The Ivanov's method was found to be the most accurate in the conditions of soybean growing in the south of Ukraine under sprinkling irrigation while linear combination of four considered methods gives an additional increase of accuracy by 6.5%.