WATER REQUIREMENT FOR MAIZE CROP UNDER CLIMATE CHANGE IN MIRAB ABAYA WOREDA, SOUTHERN ETHIOPIA

Abstract

Climate change is a topic of discussion worldwide including Ethiopia. Ethiopia is one of the country’s most vulnerable to the impacts of climate variability and change on agriculture. This study investigates, crop water requirements under climate change scenarios for maize crop at Mirab-abaya woreda. Dynamically downscaled climate model outputs were obtained from CORDEX-Africa program for Representative Concentration Pathway (RCP) of both RCP 4.5 and RCP 8.5 scenarios which were used for future climatic conditions near-term climate; (2021 – 2050). The projected data was quality checked, bias corrected and model performance was evaluated. Mann Kendall trend detection and Sen’s slope estimator were used by XLSTATA to evaluate the trends of projection and to detect changes. Hargreaves method were used to estimate Current and future crop evapotranspiration of Maize. The result for observed future climate revealed that the maximum and minimum temperature increase during all time. However, Projections of future rainfall suggest that annual rainfall decreases in both scenarios, the current and future potential evapotranspiration show that increasing trend in both case except observed Mirab-abaya station. Crop Water Requirement A Computer Program for Irrigation Planning and Management (CROPWAT 8.0) has been used to estimate crop water requirement for maize. The result shows future Crop Water Use nd Irrigation Water Requirement of Maize will increase in the study area. The reason for this is due to increase in air temperature and decrease in average rainfall in future years. Therefore, mitigation and adaptation strategy and water harvesting are needed for cropping season to have effective production in the Mirab Abaya Woreda.