Can blue carbon contribute to clean development in West-Africa? The case of Guinea-Bissau

Guinea-Bissau includes large extensions of mangroves (Avicennia germinans (L.) L., Rhizophora mangle L., Laguncularia racemosa (L.) C.F. Gaertn, Conocarpus erectus L., Rhizophora racemosa G. Mey, Rhizophora harrisonii Leechm, and Machaerium lunatum (L.f.) Ducke). These wetland forests are among the most carbon (C)-rich ecosystems in the tropics, but deforestation processes may be contributing by as much as 10 % of carbon emissions from the global forest sector. Therefore, avoiding mangrove deforestation can contribute to mitigation of climate change in addition to preserving the many other vital services that these ecosystems provide. The main objective of this study is to analyze the extent to which the revenues generated by the C retained in standing mangroves can cover the cost of avoiding their clearance in Guinea-Bissau. Moreover, this study aims at demonstrating the feasibility of producing a spatially explicit national emissions baseline in a country where data, technology, and capacity are still mostly absent. It also discusses the requirements and costs of implementing the measuring, reporting and verification system needed to make C payments a reality. The analysis relies on both the quantification of C stock dynamics in mangroves and the calculation of expected returns from avoiding their clearance, given necessary investment and C prices in the market. Methodologies based on science and Earth observation technology are used to fulfil the first requirement and economic projections are applied to fulfil the second. In this paper, previously unavailable quantitative data on the deforestation trends and the biomass content of the mangroves of Guinea-Bissau are provided at national and local levels, and compared to values presented for other regions. Additionally, a national mangrove C reference emissions level (REL) is established and an assessment of the mitigation potential of mangroves, nationally and locally, is performed. The main conclusion of the analysis presented is that, if the price of avoided carbon dioxide (CO 2 ) emissions is above the United State Dollars (USD) 6.69 to USD 7.20/t range, and governance risk can be contained, it is possible to delineate cost-effective activities to avoid deforestation of mangroves and promote climate change mitigation activities in Guinea-Bissau using C revenues alone. Copyright Springer Science+Business Media Dordrecht 2015