How to integrate wetlands in urban planning to achieve greater resilience? The case of Douala IV urban municipality (Cameroon)

Integrating wetlands into urban planning is a critical challenge for sustainable and resilient cities worldwide. This study examines the Douala IV urban municipality in Cameroon, where wetlands face intense pressures from population growth, industrial expansion, and unregulated urbanization. Using a mixed-methods approach combining GIS-based spatial analysis, field observations, and 27 semi-structured interviews with key stakeholders, we quantified the extent and rate of wetland loss. Our results indicate that mangrove areas decreased from 1591 ha in 1990 to 541 ha in 2024, corresponding to an annual loss rate of 2.40 ​% between 1990 and 2012 and 2.32 ​% between 2012 and 2024, reflecting persistent degradation despite the adoption of a municipal land-use plan in 2012. This rapid decline amplifies the socio-environmental vulnerability of local populations, compromising natural flood mitigation, water purification and groundwater recharge. Stakeholder interviews reveal that governance inefficiencies, overlapping institutional roles, and weak enforcement of environmental regulations contribute significantly to wetland encroachment. Our findings highlight the urgent need for targeted interventions, including zoning revisions, and participatory planning, to integrate wetlands into urban planning. By linking wetland degradation with urban vulnerability, this study provides evidence-based insights for policymakers and urban managers seeking to strengthen socio-ecological resilience and reduce urban population vulnerability.