Characterisation of Coastal Dune Systems in Lekki-Epe, Lagos State

Coastal dune systems represent dynamic geomorphic features that provide critical ecosystem services including coastal protection, sand storage, and habitat for specialised plant and animal communities. This study characterises the coastal dune morphology, vegetation, and sedimentary properties of the Lekki-Epe barrier dune system, Lagos State, South West Nigeria, which faces increasing pressure from real estate development, sand mining, and vehicular access tracks. Geomorphological mapping using drone-acquired photogrammetric surveys at 10-centimetre resolution delineates foredune, blowout, parabolic dune, and hind dune zones along a 25-kilometre dune transect. Sediment samples from ten cross-shore profiles are analysed for grain size, sorting, and organic carbon content. Dune vegetation surveys record species composition, percentage cover, and the relationship between plant functional types and dune morphodynamic stability. Change detection analysis using Google Earth historical imagery from 2010 to 2024 quantifies dune migration rates and volume losses attributable to human disturbance. The study also documents evidence of dune reactivation and blowout expansion in areas where vegetation removal has destabilised the dune surface. Findings demonstrate that intact foredune vegetation cover is the strongest predictor of dune stability, with artificially revegetated sections showing intermediate stability characteristics. Recommendations address the need for a protected dune corridor policy and prohibition of motorised vehicle access. Keywords: coastal dunes, Lekki-Epe, dune morphology, Lagos, coastal geomorphology