Evaluation and Application of System Dynamic Model for Determination nitrate leaching in the agricultural lands under sugarcane cultivation under climatic scenarios in Amirkabir Sugarcane Agro-Industry

The nitrogen cycle in the soil is an important part of the nitrogen cycle in the world and is largely influenced by climate change. The developed model was calibrated and evaluated by system dynamics method in order to simulate nitrogen behavior in soil in Amirkabir sugarcane Agro-Industry. Data from complete irrigation and fertilization treatments (depth of irrigation was 120 mm and 4 split equal to 450 kg.ha-1) were used to calibrate the model. Also, treatments of 150, 250 and 350 kg.ha-1 were used to evaluate the model. In order to goals of this study, the output of three models of BNU-ESM, CESM-CAM and EC-EARTH was applied with two scenarios RCP2.6 and RCP8.5. The results showed that climate change would increase nitrate losses, mineralization and ammonium sublimation. The amount of nitrate losses in the EC-EARTH2.6 climatic pattern showed an increase of 5% for future period (2016-2035) compared to the base period (1971-2000). Mineralization in the base period was equal to 93.5 kg.ha-1, which is less than the values obtained with less variation models. This phenomenon also reduces the process of denitrification from 29.65 to 20.1 kg.ha-1. The change from the RCP2.6 to RCP8.5 scenario has led to an increase in nitrate losses, mineralization and ammonium volatilization, which indicates the effect of increasing the concentration of carbon dioxide gas on these processes.