Simulating Regional Crop Growth and Yield by Using GIS-based EPIC Model

With global warming and increasing of extreme climate evens, climate change may impose positive or negative effects on crop growth and yield. The traditional crop productivity simulations based on crop models are normally site-specific. In this study, the spatial crop model is developed by integrating Geographical Information System (GIS) with Erosion Productivity Impact Calculator (EPIC) model to simulate regional crop growth and yield. Data are exchanged using ASCII or binary data format between GIS and EPIC model without a common user interface. The GIS-based EPIC model is applied to simulate the average corn and wheat yield of 1980s in North China. Compared with the statistical yields, the crops yield of Shandong and Beijing is underestimated by the GIS-based EPIC model, especially for Beijing. However, the errors are mostly less than 10%, except that in Beijing and Shandong. Thus, the simulation accuracy of the GIS-based EPIC model is acceptable. The simulation accuracy can be improved by using the detailed field management information, such as irrigation, fertilization and tillage.