Satellite ET-based irrigation performance: Strategies to increase rainfed crops production in the lower Baro watershed, Ethiopia

Abstract

Satellite-based irrigation performance is a valuable tool for improving yields in irrigated areas across the world and requires adequate land for long-term development. This study aimed to increase irrigation performance and yield gap variation of rainfed crops using the database of FAO’s Water Productivity Open Access Portal (WaPOR) and the Global Yield Gap Atlas. The evapotranspiration ( ET) performance of irrigation is expressed in equity ( CV of ET), reliability, adequacy ( CV of ET), and water productivity (kg∙m-3). The rainfed crops are interpreted in terms of metric tonnes/ha. Specifically, 20,325 km2 of suitable pastoral land across eight sub-classes was converted to rainfed rice, sugarcane, maize, and vegetable crops. Results showed that the R2 value was 0.97 at Baro Itang and –0.99 at Sor Metu, with the Baro Gambella sub-catchment having the largest yield gap of 4.435.2, 8.870.4, and 10.080∙106 kg when the yield increased by 1/3, 2/3, and 3/4. On the other hand, Gumero Gore had the smallest yield gap of 10,690, 29,700, and 33,750 kg, respectively. The management regime was 2.87, 0.87, and 0.35 kg∙m-3 for growers in the estate, farmer association, and individual, respectively. The study concludes that no single irrigation technique can be considered the best, and a thorough analysis of spatiotemporal variation of the irrigation performance indicators and the yield gap in the water-scarce lower Baro watershed is required.

Keywords

• crop water productivity
• evapotranspiration
• irrigation performance
• lower baro
• yield gap