Blue carbon reservoirs – main or side effect

Biogeochemical interventions directed towards either the protection or intentional enhancement of existing blue carbon reservoirs are often presented as a potential “win-win” scenario for climate change mitigation.

Fundamental to the efficacy of such interventions is the insight that in most cases the temporal change in the “blue” (carbon) inventory is 1-3 orders of magnitudes lower than the changes of the dissolved carbon reservoirs driven by ecosystem processing. These dissolved carbon reservoirs are directly connected with atmospheric CO2 through the marine inorganic carbon system. Hence, the potential of Blue Carbon approaches may be much larger (or smaller) than implied by turnover in the living biomass or residual organic burial terms.

 

We discuss a suite of locally focused full ecosystem carbon budgeting studies to provide a glimpse into specific processes critical to carbon processing in blue carbon ecosystems. These processes can at times amplify, cancel out, or even reverse the effects of genuine, often easy to measure, biomass accumulation.

As the public desire for blue carbon projects continues to grow, we call for a pressing need for a new integrated approach to carbon accounting, which could ensure that Blue Carbon management results in the desired and marketed climate effects.