Coupled simulation on soil-water-nitrogen transport and transformation and crop growth

Quantitative description of the soil-water-nitrogen transport and transformation in soil-crop system is very important to the high efficient use of water and nitrogen resources and protection of water and soil environment. A coupling model was developed to simulate the soil-water-nitrogen transport and transformation and crop growth based on the dynamic processes of soil water, heat and solute transport and transformation, and with considering the variation of meteorological factors and the dynamics of soil water and nitrogen and their impact on crop growth. The data sets of 2007–2008 field experiments for winter wheat with different irrigation depth were used to validate the soil-water-nitrogen transport and transformation with crop growth simulation model. The results indicated that the simulated values of soil water content, soil nitrate concentration, grain yield, biomass and evapotranspiration were in good agreement with the observed values. The model can be used to simulate the dynamics of soil water and nitrogen change pattern and crop growing pattern for different crop species under different water and nitrogen management practices, and thus the optimal water and fertilizer management pattern for farmland can be obtained.