Mechanisms, processes, and implications of blue carbon sequestration and pollution control for climate change mitigation

Mangroves, seagrass beds, and salt marshes are examples of blue carbon ecosystems that are essential to the global carbon cycle because they store atmospheric CO2 in biomass and sediments. In order to assess the biogeochemical processes, sequestration rates, and environmental factors that control carbon storage and emissions in these ecosystems, this study summarizes data from peer-reviewed research published over the previous 20 years. Seagrass and salt marsh systems sequester 30–218 g C m⁻ 2 yr⁻ 1 and 150–250 g C m⁻ 2 yr⁻ 1 , respectively, whereas mangroves have considerable belowground carbon storage (up to 1,023 Mg C ha⁻ 1 ) supported by anoxic, sulfate-reducing sediments and vertical accretion rates of 3–10 mm yr⁻ 1 . Additionally, we evaluate carbon-loss mechanisms that might turn blue carbon sinks into net carbon sources, such as sediment erosion, methane generation, and oxidation after disturbance. Sea level rise, nitrogen loading, hydrological changes, and pollution are some of the factors that affect carbon stability and sequestration effectiveness. Our research as a whole shows that while restoration can recover 50–90% of depleted carbon stocks over several decades, intact blue carbon ecosystems significantly contribute to climate mitigation. These results highlight the significance of protecting coastal ecosystems and incorporating blue carbon solutions into frameworks for carbon offsets, pollution management, and climate adaption.