Abstract
The tremendous increase in industrial development and urbanization has become a severe threat to the Chinese climate and food security. The Agricultural Production System Simulator model was used to simulate soil nitrogen in black soil in Yangling Jilin Province for 20 years. The observed values are consistent with the simulated values. The predicted values of total soil NO(3)(-)-N and NH(4)(+)-N nitrogen are 10 kg ha(-1) and 5 kg ha(-1) higher than the observed values. The total soil NO(3)(-)-N loss has the same trend as the rainfall, and it increases with the number of rainfall days over the years. The average 20 years losses of NO(3)(-)-N and NH(4)(+)-N observed were 1375.91 kg ha(-1), and 9.24 kg ha(-1), while in the simulation increase was 1387.01 kg ha(-1) and 9.28 kg ha(-1), respectively. The difference between the observed and simulated values of NO(3)(-)-N and NH(4)(+)-N of mean loss was 11.15 kg ha(-1) and 0.04 kg ha(-1) respectively. Moreover, our findings highlight the opportunity further to improve management policies (especially for nitrogen) to maintain crop yield.