Mangrove swamp at a saline/fresh water interface near Creek Town, Southeastern Nigeria

The Creek Town mangrove swamp occurs at the saline/fresh water interface within the ever-wet; humid tropical zone of Southeastern Nigeria. A survey of the swamp was undertaken to map the mangrove physiographic habitats, and to obtain vegetation and environmental measurements. Due to the dynamic nature of the swamp landscape, several physiographic mangrove habitats have evolved. Habitat differences relate to swamp gradient, salinity variation, substrate texture ,and carbonate content of the soil. Species presence and abundance vary between the habitats. Diurnally flooded tidal creek and distributary wetlands are dominated by Acrostichum aureum and Nypa fruticans in association with Rhizophora spp. and Avicennia africana. Raphia spp. and Vossia cuspidata which are upland forest species have invaded the supratidal and hinterland levee habitats due to increasing salinity tolerance and competitive abilities. Vegetation zonation is apparent from the channels inland but there are quirks in the zonation pattern due to variations in local topography within the species zones. The environmental conditions and species distribution are similar to other transitional mangroves of the West Africa-Americas Mangrove Formation.