Total Ecosystem Carbon Stocks Across Different Mangrove Forest Conditions in Lamu and Tana River Seascapes, Kenya

Mangrove forests provide critical ecosystem functions and services, including carbon sequestration, biodiversity support, coastal protection, and livelihood support for coastal communities. However, they are increasingly threatened by both natural processes and human activities, which reduce their ecological integrity and carbon storage capacity. This study evaluated effects of disturbance on forest structure, regeneration, and carbon stocks in mangrove ecosystems of Lamu and Tana River seascapes, Kenya. Data was conducted in 111 square plots established perpendicular to the waterline along belt transects. Tree structural attributes, regeneration patterns, and soil carbon were assessed across sites classified as highly, moderately, and least disturbed.A total of six mangrove species were recorded in Lamu and seven in the Tana River, dominated by Rhizophora mucronata and Ceriops tagal. Results showed declining values for structural attributes with increasing disturbance, with reduced stem density, tree height, and basal area in highly disturbed sites. However, moderately disturbed sites in Tana River exhibited relatively higher biomass and basal area, suggesting possible compensatory growth. Total ecosystem carbon decreased consistently with disturbance, from ~419 to 216 Mg C ha⁻¹ in Lamu and from ~391 to 177 Mg C ha⁻¹ in Tana River, with soil organic carbon forming the dominant carbon pool across all sites.Regeneration analyses showed robust seedling recruitment in the least and moderately disturbed sites, whereas the highly disturbed sites had limited juvenile establishment. The study demonstrates that disturbance significantly impacts mangrove ecosystem structure and reduces carbon storage potential. The findings highlight the importance of conserving intact mangroves, promoting sustainable use of harvested areas, and restoring degraded forests to enhance ecosystem function, carbon sequestration, biodiversity conservation, livelihoods and coastal resilience. Strategic management and long-term monitoring are recommended to safeguard these vital coastal ecosystems.