Dynamics of Urbanisation, Environmental Transformation, and Ecosystem Service Trade-offs in the Lagos Metropolitan Region: A Coupled Human-Environment System Analysis

Lagos Metropolitan Region's extraordinary pace of urban growth constitutes a natural experiment in coupled human-environment system dynamics, generating ecosystem service trade-offs and environmental transformations of global significance within a single sprawling coastal mega-region. This doctoral research analyses the co-evolutionary dynamics of urbanisation, environmental transformation, and ecosystem service trade-offs in the Lagos Metropolitan Region using a coupled human-environment systems framework drawing on land system science, urban political ecology, and ecosystem service science. A multi-decadal land use and land cover change analysis based on 30-metre resolution satellite imagery from 1990 to 2024 is integrated with spatially explicit ecosystem service valuation, household livelihood survey data from 500 metropolitan households, and qualitative governance analysis drawing on 75 institutional interviews. Ecosystem service trade-off analysis identifies the configurations and magnitudes of service losses and gains across three spatial governance zones: Lagos State core, Ogun State metropolitan fringe, and peri-urban agricultural transition zones. The coupled human-environment analysis reveals non-linear feedbacks between informal settlement expansion, drainage infrastructure failure, and flood damage cycles in which poor urban households are both drivers and victims of environmental degradation. Original theoretical contributions include a metropolitan scale urbanisation-ecosystem service decoupling index and a typology of peri-urban environmental transformation trajectories relevant to West African coastal cities. The study provides evidence for Lagos State Urban and Regional Planning Authority's Long Range Development Plan and contributes to global urban sustainability science through a Southern megacity perspective. Keywords: urbanisation, ecosystem services, Lagos Metropolitan Region, coupled human-environment systems, land system science.