HYDRUS-1D modelling of soil water regime in a rational irrigation pilot application (Nigrita, Greece).

Accurate estimation of the hydrological features in the unsaturated zone is mandatory for the effective planning of irrigation strategies. Irrigation scheduling depends on crop and soil type as well as climatic characteristics and is usually empirically conducted. This paper simulates the water flow in order to model the soil water balance in three agricultural fields (maize, cotton, alfalfa) located in the River Strymonas basin using the HYDRUS-1D model. The model is fed with meteorological data, soil data and soil moisture measurements. After the calibration, through HYDRUS-1D's inverse solution, model results were used to evaluate the irrigation activities applied in the pilot application fields in terms of irrigation dose, irrigation interval and soil moisture variation for the cultivation period. In addition, in order to measure the efficiency of the irrigation method evaluated in this work, water productivities for all three fields were compared with productivities yielded from similar applications and experiments as well as precision irrigation experiments found around the world at similar climates with the one at Nigrita. [ABSTRACT FROM AUTHOR]