Natural resource opportunities and challenges for rural development in marginal grabens - The state of the art with implications for the Rift Valley system in Ethiopia

- Marginal grabens along Rift Valleys are rich in water resources.
- Marginal grabens have fertile soils as a result of alluvial deposition for centuries.
- Riverbed incision, river basin closure, salinization and excessive sediment deposition are visible challenges for livelihood of graben communities.
- Marginal grabens are potential agricultural lands.
- Farmers-scientists lead land evaluation must lead to sustainable graben management.

With increasing global population, the production of more food and fiber has led to an expansion of the areas under cultivation, of which low-lying flat areas (including marginal graben bottoms) are of particular interest. Marginal grabens have been the center of agricultural development around the world. This paper examines the opportunities and challenges related to natural resources in rural development and highlights the knowledge gaps and priorities for the research and development of marginal grabens with specific reference to Ethiopia's Rift Valley marginal grabens, which have sufficient land banks to accommodate irrigated agriculture. Repeated transect walks, focus group discussions and interviews carried out in Northern Ethiopia, have been employed to address these research questions, while content analyses and descriptive statistics have been used to analyze the data. This paper shows that marginal grabens are rich in blue and green waters due to their topographical and geological characteristics, and are fertile plains suitable for irrigated agriculture. However, marginal grabens can reach closing and closed basin status in arid and semi-arid environments. Salinization, waterlogging, incisions and sedimentation also threaten the livelihoods of smallholder farmers in the grabens. Thus, appropriate river basin governance, integrated land management, and wise water allocation is needed to optimize land and water resources during rural development in the (semi)closed marginal grabens of northern Ethiopia and elsewhere in the world with similar geographical settings.