Land Cover Changes in the Upper Great Ruaha (Tanzania) and the Upper Awash (Ethiopia) River Basins and their Potential Implications for Groundwater Resources

Kiran M. Chandrasekharan, Karen G. Villholth, Japhet J. Kashaigili, Gebrehaweria Gebregziabher, Paulo J. MandelaBazaz  | 2023

Summary

Unprecedented resource demands due to population growth, increasing food demand and urbanization, exacerbated by climate change, have led to unsustainable development pathways in many parts of the world. Information about the status and trends of land and water resources is a critical requirement for long-term policies and strategies for equitable and sustainable development. Satellite remote sensing offers cost-effective, rapid and reproducible methods to monitor indirectly the utilization patterns and trends of several natural resources such as land and water resources.

This report presents the results of a land cover change analysis conducted in two headwater catchments of river basins in sub-Saharan Africa, where impoverished communities critically depend on local land and water resources: the Upper Great Ruaha River Basin (UGRRB) in Tanzania (20,823 km2 , approx. 800,000 people) and the Upper Awash River Basin (UARB) in Ethiopia (10,695 km2 , approx. 5.3 million people). The two basins represent areas which are significantly different in terms of agricultural development and patterns of water resource use. UARB represents an agricultural region, which has emerging commercial farms, expanding urban centers and threatened natural vegetation. UGRRB still has significant areas under natural vegetation but expanding areas under irrigation. In UGRRB, surface water is the main source of irrigation water, while in UARB, groundwater resources are increasingly used for irrigation by smallholder farmers and commercial farms.