In the Volta Basin of West Africa, rivers represent the life-blood of cultivation in the semi-arid north and are the key to hydropower generation in the south.
Today, agricultural runoff, land use change and construction of major hydroelectric dams in the Volta Basin are degrading these life-supporting rivers.
Mapping opportunities for conservation and Sustainable Development Goals
In the Volta basin, the ‘Mapping Ecosystems Services to Human well-being’ (MESH) toolkit is being used to compare strategies for conserving hydrological ecosystem services and meeting national SDG commitments. MESH is an integrated modeling framework to estimate ecosystem service supply across a landscape and translate these estimates into SDG-relevant outcomes. It is built to support cooperative sector planning and evaluate trade-offs between landscape development objectives.
The toolkit is being used to identify cost-effective ecosystem-based opportunities to conserve waterways and identify synergies between food production, water supply and carbon storage goals. This comparison will be used by the Volta Basin Authority (VBA) to support onoing efforts by its six member states to implement an ambitious policy on riparian buffer protection set out in the VBA Strategic Action Plan. Although the widespread implementation of this policy is hindered by lack of funding, it gives recognition at the national scale of the relationship between land management, ecosystem services and human well-being.
Piloting MESH to filter land use priorities for optimal results
Landscape modelling approaches can be used to explore the impacts of alternative riparian buffer scenarios in relation to land-use activities in the landscape. Illustrating these cause-and-effect relationships allow local, district and national organizing bodies to make decisions on how to prioritize or balance activities, such as food production or water regulation, according to its impact on locally important ecosystem services.
In the Volta Basin, MESH was used to compare three alternative riparian buffer scenarios across a number of SDG-related landscape outcomes. The goal was to determine the course of action that would be more cost-effective for sediment retention, while providing a range of other benefits. Riparian buffer management activities were prioritized on areas with high erosion potential but differed in whether they were targeted to agricultural or non-agricultural lands and whether they used natural vegetation restoration or agroforestry as the management activity.
The results of the three piloted investment strategies can have strong implications for policy that reach beyond VBA’s buffer policy to the achievement of Sustainable Development Goals on water quality (SDG 6), food production (SDG 1&2), landscape nutrition (SDG 2), carbon sequestration (SDG 13) and water yield for hydropower (SDG 7). These results are currently undergoing analysis and will be released in the coming weeks.
Modelling the impact of ecosystems on livelihoods
Ecosystem services make important contributions to peoples’ livelihoods, especially in rural areas where services are often directly consumed or integral to production systems. However, the common practice of using economic valuation to measure this contribution poorly captures the impact of eco-services on peoples’ well-being in areas where markets are weak or non- existent. More relevant valuation of ecosystem services for human well-being could be captured in their contribution to livelihood and development targets embodied in the UN Sustainable Development Goals (SDGs).
Sylvia Wood is a Postdoctoral Fellow, Bridging Agriculture and Conservation Initiative with Bioversity. Sylvia’s work supports the ‘Bridging Agriculture and Conservation Initiative.
Sarah Jones is a research assistant with Bioversity International and PhD student at the King’s College London University.
This work was a collaborative effort with the support of NCEAS Science for Nature and People program, CGIAR WLE and PIM support. Their work links the importance of biodiversity to agricultural production in smallholder farming systems.