Estimated Of Evapotranspiration And Crop Water Requirements Of Some Selected Crops At Tono Irrigation Scheme In The Upper East Region Of Ghana

2016

English

A research was conducted at Tono Irrigation area in the Upper East Region of Ghana to estimate evapotranspiration and crop water requirement of some selected crop. FAO Penman-Monteith and Surface Energy Balance System Algorithm methods were used to estimate Potential crop and actual crop evapotranspiration during 2008/2009 crop season. This was done using climatic parameters like temperature, rainfall, wind speed, relative humidity and sunshine hours and fourteen (14) Aster images acquired in November, December, January, February, March and April which were the period of irrigation in the study area. The test crops included rice, tomato, onion and cowpea which are part of the major crops cultivated in the study area. The research findings revealed that rice has the highest evapotranspiration and crop water requirement than tomato, cowpea and onion. Potential crop and actual crop evapotranspiration were 902 and 610, 787 and 588, 381 and 365, 496 and 466 respectively. Also reference crop evapotranspiration was the lowest at the peak of the rainy season which gave lowest temperature and irrigation water demand. The field study also revealed that infilteration was very prominent at the valley bottom area where rice was cultivated. The result from the study can serve as a guide by irrigation managers in quantifying irrigation performance and the amount of water needed by each crop daily, monthly and seasonally.

Asaana, J.; Nketia, K. A.; Asamoah, E.; Asenso-Gyambibi, D.