Comparative assessment of mangrove biomass and fish assemblages in an urban and rural mangrove wetlands in Ghana

Abstract

Mangrove wetlands are one of the most important ecosystems on earth, providing habitats for both marine and terrestrial organisms as well as supporting essential human services. However, high dependence of humans on these systems is leading to significant transformation of mangrove wetlands and reduction in their ecosystem services including fisheries. The objectives of this study were to estimate the biomass of two mangrove wetlands in Ghana within urban and rural contexts and determine the fish fauna assemblages as art of baseline setting. The study used the structural parameters of mangrove species and allometry to estimate the biomass of both forest systems. Fish community structure was determined based on ecological surveys. The findings show that the standing biomass of the mangrove forests were significantly higher (p < 0.01) in the rural wetland (394.49 t/ha) compared to the urban wetland (126.29 t/ha). Fish fauna assemblages, referring to species richness and diversity were higher in the urban wetland at 4.21 and 2.64 respectively compared to the rural wet-land at 3.46 and 2.09 respectively. This paper concludes that a well-developed mangrove system with high mangrove biomass may not necessarily imply high fish species richness and diversity.