EVALUATION OF REFERENCE EVAPOTRANSPIRATION FOR GERIYO IRRIGATION PROJECT USING FAO-56 PENMAN MONTIETH MODEL IN YOLA, NIGERIA
Estimates of reference crop evapotranspiration (ETo) are widely used to define crop water requirements. These estimates are used in the planning process for irrigation schemes to be developed as well as to manage water distribution in existing schemes, thus accurate determination of reference evapotranspiration is very essential for precise computation of crop water use and productivity. This study was conducted to evaluate reference evapotranspiration for Geriyo Irrigation Project using FAO-56 Penman monteith model which is an effective tool for irrigation planning and management. Climatic data for the period of 15 years (2004-2019) were obtained from Upper Benue River Basin Development Authority metrological gauge station, Yola, Adamawa State, Nigeria for analysis. Climatic parameters such as solar radiation, slope of saturation vapour, Saturation vapour deficit, actual saturation vapour, and psychometric constant were determined and used in the FAO-56 Penman monteith model. The model was validated using evapotranspiration obtained by Pan Evporation method and had an R2 value of 0.715. Results indicated that mean reference evapotranspiration value of 3.56 mm/day was obtained for the study area. The result revealed that solar radiation had the highest effect on evapotranspiration since it provide the energy needed for evapotranspiration to take place.The reference evapotranspiration determined using FAO56PM can be used for effective irrigation planning and management that will improve crop production and water productivity in the study aera.
Authors : Tya, T. S. K. and Umaru, A. B.
Category : Open Access Volume (Issue) : 7(1) Date Uploaded : 14th June 2021