Evaluation of water movement and nitrate dynamics in a lysimeter planted with an orange tree

摘要: a b s t r c Adoption of high input irrigation management systems for South Australian horticultural crops seeks to provide greater control over timing and fertilizer applications. The HYDRUS 2D/3D model was used simulate water movement in the soil under an orange tree planted field lysimeter supplied with 68.6 mm 29 days. Simulated volumetric contents statistically matched those measured using capacitance probe. Statistical measures (MAE, RMSE, tcal) indicating correspondence between simulated moisture content were within acceptable range. modelling efficiency (E) relative (RE) satisfactory range, except RE at day 19. daily cumulative drainage fluxes also values well. Cumulative flux 48.9% applied water, large losses even controlled High due light texture rainfall (70 mm) during experimental period. root uptake 40% water. calibrated evaluate several scenarios involving nitrate fertigation. numerical analysis NO3-N dynamics showed that 25.5% taken up by 15 days fertigation commencement. rest (74.5%) remained soil, available uptake, but vulnerable leaching later growing season. seasonal simulation revealed accounted 50.2% nitrogen as fertilizer, plant N recovery amounted 42.1%. scenario further application event had little impact on its citrus lysimeter. However, slightly higher occurred when late schedule, or spread out across all pulses, rather than being early middle. Modelling pulsing uptake. Applying less (50% 75% ETC) resulted efficiency. This study applications crop can be better regulated enhance inputs conditions.