Participatory scenarios and spatial modelling to explore mangrove ecosystem services futures in Lamu, Kenya

Background

Lamu County, Kenya contains Kenya’s most extensive mangrove forests, which provide many vital ecosystem services (ES) for local communities (e.g., nutrition, building material, coastal protection, climate regulation). Land use and land cover change (LULCC), such as coastal development or infrastructure projects, threaten mangroves and their ES. Participatory scenario planning can help communities develop models of future LULCC grounded in both scientific evidence and local experience. Using these models in Lamu could inform future policy to preserve Lamu’s mangroves and balance country-level economic needs with local ES.

Goals and Methods

This study uses the Kesho participatory scenario modeling framework to combine qualitative stakeholder narratives, quantitative assumptions, and spatially explicit modeling to project future LULCC scenarios and their effects on ES in Lamu County, Kenya. Local stakeholders reviewed historical LULCC and drivers, identified future sources and areas of LULCC, and discussed how future LULCC would influence mangroves and ES provisioning. The authors combined this information with land cover data from 2000-2020 to develop models and maps of future LULCC scenarios, using the Land Change Modeller in TerrSet. These maps and results were presented to the original stakeholder panel for feedback and validation.

Conclusions and Takeaways

This participatory process yielded four future scenarios of LULCC with varying levels of governance, environmental protection, and collaboration between communities and institutions. Scenario 1, which uses collaborative governance to balance economic development with environmental conservation, would sustain both economic and ecological benefits. Conversely, Scenario 4 has weak governance and an emphasis on short-term economic gains from development, which would quickly degrade the environment and decrease ES supply, harming both the environment and local livelihoods. While mangrove area would shrink in all of the future scenarios, the economic value of ES would increase in scenarios that emphasize good governance and preserving mangrove ecosystem health. These insights into sustainable future scenarios show how participatory modeling can inform important policy, infrastructure, and development decisions to best align with the economic, social, and environmental needs at both a local and country-level scale.