ALMANAC model is a practical model, which was first used as a part of EPIC model to simulate the decline of land productivity caused by soil erosion. ALMANAC model can simulate crop growth process and soil water balance process, including: light interception by crop leaves, biomass accumulation, biomass distribution in different organs of crops, full utilization of water by crops, absorption of nutrients, and constraints of environmental factors on crop growth process, such as water stress, temperature stress and nutrient stress. The ALMANAC model provides a util editor. This is a very friendly interface database editing program, can directly provide users with the input variable database prompt operation.