Carbon Sequestration and The Boreal Forest:

Processes

Ecosystem level carbon sequestration is dominated by three processes, which we will discuss in detail below.  These processes are photosynthesis, respiration, and fire.

Photosynthesis is the process by which light energy is utilized to facilitate the reduction of CO2 to sugars.  It is the source of all carbon that is present in an ecosystem and is divided into two processes, the light reactions and the photochemical reduction (PCR) cycle.  Click here to read about factors that affect photosynthesis.  The general equation for photosynthesis is as follows:

While photosynthesis determines how much carbon enters a system, respiration is the process that determines how much of it actually stays there.  All living things respire, though for our purposes we are most concerned with respiration by the plants and soil (actually all the little things living in it) of an ecosystem.  Click here to read about factors that affect respiration.  The generalized equation for respiration is as follows:

C6H12O2 + 6 O2 <-> 6 CO2 + 6 H2O

Fire plays an important role in boreal ecosystems, both in an ecological sense and in terms of the forest’s ability to sequester carbon.  Fire affects carbon sequestration both directly and indirectly.  Directly, fire results in a large, non-respiratory release of carbon from the ecosystem by burning both vegetation and organic matter in the soil.  Indirectly, fire may stimulate respiratory release from the soil and from new plant growth after a burn and alter the stand structure of the forest.