Valuation and Estimation of Carbon Stocks and Sequestration Potential of Mangroves in the Ahanta West District of Ghana

As part of nature-based solutions to addressing greenhouse gas emissions and adapting to the severe impacts of global climate change, the government of Ghana, through its Ministry of Environment, Science, Technology, and Innovation (MESTI) is leading the development of policies and implementation of programs to protect and restore mangrove ecosystems, which have reduced in coverage over the years. This research was conducted to present an inventory of the mangrove carbon stocks and their estimated monetary value in two communities in the Greater Cape Three Points (GCTP) area of Western Ghana – Princess Town and Cape Three Points, in support of national mangrove conservation efforts. The assessment, which was conducted on three mangrove ecosystems in the study area– Nyan River estuary (38.11 ha) and Ehunli lagoon (17.54 ha) in Princess Town, and the rocky bay in Cape Three Points (1.26 ha). It estimated carbon stored in the systems at 291.96 ± 96.69 MgC/ha, 407.68 ± 131.62 MgC/ha, and 395.95 ± 127.61 MgC/ha respectively. Carbon sequestered by each of the systems was estimated at 41,836 Mg/CO ₂ e for the Nyan estuary mangrove system, 26,886.66 Mg/CO ₂ e for the Enhuli lagoon mangrove system, and 1,875.85 Mg/CO ₂ e for the rocky bay mangrove system – at a carbon market value of US$12,0167.23 MgCO₂e/ha, US$ 77,227.64 MgCO₂e, and US$ 5388.09 MgCO₂e, respectively. The Enhuli Lagoon mangrove ecosystem which provides a sanctuary for monkeys and is traditionally protected by cultural norms, recorded the highest carbon storage amount. Results of the assessment inferred that all three ecosystems sequestered high amounts of carbon, emphasizing their important role as carbon sinks. The systems were also observed to be in a near-pristine state, providing a wide range of ecosystem services, both directly and indirectly, to support human well-being.