Regional mechanistic estimations of sugar-cane water use

The application of a sugar-cane model, evolved from the mechanistic model SWAP, in the assessment of the sugar-cane water use and yields in Havana Province is shown. The model was interfaced to the GIS ILWIS in order to produce regional results. The soil hydraulic properties of all the sugar-cane cropping areas in the province were calculated through pedotransfer functions using available information from a 1:25 000 soil map. The daily values of the modified Penman evapotranspiration (ETP) were considered as the top boundary condition in the simulations. Free drainage was assumed as the bottom boundary condition of the 2-m layer. A weather generator was used to generate 50 years of daily rainfall and maximum ETP records. Site-specific assessments of water effects on sugar-cane yields were carried out, as well as water-management recommendations for each location. The present results can be used as a methodological guide for recommending the sugar-cane water management in any other part of the world.