Carbon sequestration describes the process in which carbon dioxide (CO₂) is removed from the atmosphere and subsequently stored through biological, chemical, or physical processes.
In the case of woodland creation, trees use solar energy to convert CO₂ and water into carbohydrates and oxygen through photosynthesis. These carbohydrates form the building blocks for the biomass of the tree and, therefore, the storage of carbon.
One often forgotten caveat is that trees not only photosynthesise but respire also. Through this process, trees convert some of these carbohydrates and oxygen back into CO₂, water, and energy.
As trees grow, the process of photosynthesis dominates that of respiration, sequestering carbon. Once they reach maturity, however, these processes are pretty much in equilibrium. Subsequently, the trees are emitting as much CO₂ as they are sequestering.
A carbon sink is any reservoir that absorbs more carbon than it releases.
A carbon source releases more carbon than it absorbs.
A carbon store/stock maintains a constant amount of carbon.
A Pending Issuance Unit (PIU) is a ‘promise to deliver’ a Woodland Carbon Unit in the future. For more information visit CarbonStore’s ‘Carbon Units Explained‘ page
Real: All emission reductions and removals must be proved to have genuinely taken place. (In the case
of woodland, this test is straightforward; are the trees standing and alive?).
Measurable: All emission reductions and removals shall be quantifiable. (The WCC has developed its carbon calculator to measure a woodland’s sequestration capacity).
Permanent: Carbon credits shall represent permanent emission reductions and removals. (With woodlands
liable to storms, fire, and disease, the WCC has developed its own solution to this test
Additional: The project must demonstrate that, without carbon funding, the project would not have been developed i.e. it must be additional to that which would have occurred anyway.
Independently Verified: All emission reductions and removals shall be verified to a reasonable level of assurance by an independent third party. (The WCC have currently appointed the Soil Association and Organic Farmers and Growers to undertake this audit).