Impacts of climate and land use/cover changes on the sustainability of irrigation water in West Africa: a systematic review

Abstract

Climate and LULC changes have a great influence on the hydrological processes which include evapotranspiration, infiltration, surface runoff, groundwater flow, and stream discharge regime. This study aims to review the existing literature on the impacts of climate, and LULC changes on the sustainability of irrigation water in West Africa. The future of irrigation in West Africa will be driven by strong external factors, such as rapid population growth, climate change, and LULC change. The annual average temperature is between 25.9 and 34°C. Rising temperatures have affected all sectors, including water resources, increased irrigation demand, and the sustainability of agricultural production. Reduction in precipitation will reduce river flows and increase evaporation due to a drier atmosphere, thereby reducing the amount of water available in reservoirs for irrigation. The current demand for freshwater in West Africa for irrigation purposes is expected to triple by 2050. From 1997 to 2018, forest area decreased by 24.6%, while residential and agricultural land areas increased by 140% and 11.7%, respectively, in West Africa. Effective mitigation and adaptation measures are the policy issue for the observed adverse impacts of future climate and LULC changes on the sustainability of irrigation water availability in West Africa.