A review of the shrinking and expanding Eastern Africa rift valley lakes: The case of Ethiopian and Kenyan lakes

Abstract

Study region: Ethiopian and Kenyan Rift Valley (EKRV) Study focus: The morphological changes in EKRV lakes exemplify the complex interplay between human activities and natural systems. This review investigates the spatiotemporal water level fluctuation in EKRV lakes and its causes, highlighting the gaps in existing research on the natural and anthropogenic factors. We employed a meta-analysis of the literature establishing a database of 362 documents consisting of peer-reviewed journal articles, conference proceedings, theses, and book chapters. These documents were collected from online sources and supplied by authors upon request. Of these 362 documents, 236 were critically assessed using systematic review procedures. New hydrological insights for the region: The review reveals contrasting morphological changes, with the Kenyan Rift Lakes expanding and the Ethiopian Rift Lakes either shrinking or expanding. Endorheic lakes suffered the most fluctuations due to the extensive loss of forest and woodlands in their watersheds. The research emphasizes the necessity of managing resources holistically, acknowledging the interdependence of upstream and downstream ecosystems and the significance of cross-border cooperation. The influence of climate change and the consequences of lake water level fluctuations on water quality and fragile natural resources in the Rift Valley urges interdisciplinary research integrating natural and social sciences to safeguard the invaluable ecosystem services provided by lakes sustainably.

Keywords

• East African Rift
• Size of lakes
• Shrinking lakes
• Expanding lakes