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

Land use and land cover change (LULCC) disrupts ecosystem structure and function, threatening ecosystem services and human well-being. Anticipating future trajectories is especially urgent in coastal regions, where mangrove ecosystems face anthropogenic and climatic pressures. In Lamu County, ongoing large-scale developments are expected to attract new settlements along the coastline and increase competition over land and natural resources, further intensifying pressures on mangroves. Here, we combine participatory scenario development with spatial modelling and ecosystem service valuation to explore plausible futures in Lamu County, Kenya. Using the Kesho, a diverse group of stakeholders co-produced four development scenarios to 2063, which were translated into spatially explicit LULCC maps using Landsat derived datasets and stakeholder-informed driver assumptions. A benefit transfer method was applied in two ways to estimate the value of mangroves’ provisioning, regulating and cultural services. Based on land-cover change alone, all scenarios show slight declines in value of ecosystem services. However, when scenario-specific changes in unit values were incorporated, the annual value diverged sharply, rising to USD 10.5 billion under the New Dawn scenario and falling to USD 7.6 billion under the Growth Trap. This study presents the first participatory scenario assessment in Lamu County, providing policy-relevant insights into how development pathways may shape mangrove ecosystems and the services they provide. Beyond Lamu, Kesho offers an adaptable tool for application in other mangrove-rich regions globally, supporting efforts to align local decision-making with continental and global sustainability agendas, including the African Union’s Agenda 2063 and the Sustainable Development Goals.