Estimation of Crop Water Requirement Using CROPWAT Model for Onion and Tomato, A Case Study of Raya Azebo District, Ethiopia

Abstract

Water is becoming gradually scarce worldwide. Aridity and drought are considered natural causes of scarcity of water on earth. Man-made desertification and water shortages have further aggravated the natural scarcity of water worldwide. Water scarcity has a huge impact on food production and without water people do not have a means of watering their crops and therefore, to provide food for the fast-growing population, farmers need to increase their output from existing cultivated areas to satisfy the food demand of an increasing population in the world especially in Ethiopia. Irrigation systems essential to enhance crop productivity in order to meet future food demand and ensure food security. The study was carried out to estimate the crop water requirement of onion and tomato in Raya valley, Northern Ethiopia. By using the climatic data, cropevapotranspiration (ETc)and reference crop evapotranspiration (ETo) for each crop were determined using CROPWAT 8.0.The study shows that crop water requirement of onion with a growing period of 100 days to maturity requires 366.0 mm depth of water on off season and 338.9 mm on main season respectively. Crop water requirement of tomato with a growing period of 125 days to maturity requires 509.9 mm depth of water on off season and 472.1 mm on main season respectively. These results can be used for planning and for most efficient water use and to optimize production of the onion and tomato in the study district.

Keywords:Reference Evapotranspiration (ETo), Crop water requirement (ETc), Model, Onion, Tomato,CROPWAT

DOI: 10.7176/JBAH/11-8-04

Publication date: April 30^th 2021