Three decades of pastoralist settlement dynamics in the Ethiopian Omo Delta based on remote sensing data

Samira Amos,Fritz Kleinschroth,Sileshi Mengistu

doi:10.1007/s10745-021-00257-6

Abstract

River deltas provide important livelihoods to local populations, but at the same time are under increasing anthropogenic pressure. The opening of the Gibe III dam on the Omo River in Ethiopia in 2016 attracted international attention due to the importance of the free-flowing River for pastoralist communities in the Omo Delta. Sustainable river basin management requires spatially explicit, long-term information about human settlements to mitigate negative impacts on people’s livelihoods. Based on remote sensing time-series, and supplemented with ground-truthing, we mapped settlement-dynamics of the pastoralist Dasanech tribe. The inhabited area more than doubled from 1992 to 2009. From 2009 to 2019, settlements became more permanent and concentrated in the North of the Delta. Our results indicate that the Omo Delta has overall gained in importance as a livelihood area, but that the livelihoods of the traditionally nomadic people are shifting in the context of increasing investment in infrastructure. Management of future river flow at dams should consider the location and the trajectory of change in downstream settlements.

Highlights

In large parts of the world, wetlands support local populations due to their high productivity, but at the same time are under increasing anthropogenic pressures (Mitchell 2013)
We investigated settlement dynamics in the Omo Delta within the Dasanech woreda, Southern Nations, Nationalities and Peoples Region of Ethiopia
We attribute our observations to resource scarcity that has forced Dasanech people to live in and near the Delta in the first place. This so-called ‘option squeeze’ refers to pressures on the traditional livelihood activity of livestock herding that occurred in the past half-century, including prolonged droughts, land restrictions by political forces, and conflicts among competing tribes. Previously secondary activities such as flood-recession agriculture and fishing became more important for survival and led many Dasanech to relocate towards the Omo River banks and Lake Turkana (Carr 2017a)

Summary

Introduction

In large parts of the world, wetlands support local populations due to their high productivity, but at the same time are under increasing anthropogenic pressures (Mitchell 2013). This applies to Africa, where many people directly depend on wetlands for subsistence livelihoods such as agriculture and fishing (Adams 1993; Mitchell 2013). River deltas provide important resources for local communities but are often highly degraded (Syvitski et al 2009; Tessler et al 2015). The Omo Delta in Lake Turkana is home to the indigenous Dasanech people, and is important for their livelihoods as it provides water, sediment, and nutrients for flood-recession agriculture and grazing throughout the year in an otherwise semi-arid region (Carr 2017a; Yntiso 2012)

Methods

Results

Discussion

Conclusion