Blue Carbon Investment Potential in Lamu and Kwale Counties of Kenya: Carbon Inventory and Market Prospects

Blue carbon ecosystems, particularly mangroves, seagrasses, and salt marshes, play a crucial role in climate regulation by capturing and storing huge stocks of carbon. Together with serving as habitat for fish and other wildlife, protecting shoreline from erosion, as well as providing harvestable wood and non-wood resources to society, blue carbon ecosystems offer investment opportunities through carbon markets, thus supporting climate change mitigation and sustainable livelihoods. The current study assessed above- and below-ground biomass, sediment carbon stocks, and sequestration potential of blue carbon ecosystems in Lamu and Kwale counties, Kenya; using 2020 as the baseline year. This was followed by mapping of hotspot areas of degradation and the identification of investment opportunities in blue carbon credits. Carbon densities in mangroves of Lamu and Kwale were estimated at 560.23 Mg C ha⁻¹ and 526.34 Mg C ha⁻¹, respectively, with over 70% stored in sediments. Seagrass carbon densities in Lamu (171.65 Mg C ha⁻¹) and Kwale (220.29 Mg C ha⁻¹) exceed the national average but align with global estimates. Mangrove cover is declining at 0.49% yr⁻¹ in Kwale and 0.16% yr⁻¹ in Lamu, while seagrass loss in Lamu is 0.67% yr⁻¹, with a 0.34% yr⁻¹ increase in Kwale. Under a business-as-usual scenario, mangrove loss over 30 years will result in emissions of 4.43 million tCO₂e in Kwale and 18.96 million tCO₂e in Lamu. Effective interventions could enhance sequestration from 0.12 to 3.86 million tCO₂e in Kwale and 0.62 to 19.52 million tCO₂e in Lamu. Seagrass loss in Lamu could emit 5.21 million tCO₂e. With a carbon price of $20 per tCO₂e, projected annual revenues from carbon credits amount to $3.59 million in Lamu and $216,040 in Kwale. These findings highlight the substantial climate and financial benefits of investing in blue carbon ecosystem conservation and restoration.