This diagram of the carbon cycle shows a tree absorbing carbon through its leaves and moving the carbon to its roots. Atmospheric carbon is fixed by trees and other vegetation through photosynthesis. Some carbon is internally transferred from aboveground to belowground carbon to soils. Some carbon is transferred from belowground carbon (e.g. root mortality) to the soils. Fallen leaves and branches add carbon to soils. Carbon is lost to the atmosphere through soil respiration, plant respiration and decomposition of organic matter. Below ground carbon is housed in roots and litter. Above ground carbon is housed in stems, branches and foliage. Return to September newsletter