Long Description of Figure 4:

Drawing of a tree with many organic processes listed and shown as they flow from one process to another: arrow indicating that tree takes in carbon dioxide, water and sunlight; Littering from tree produces: needles, twigs, and branches; Pedoturbation: Tree throw, earth worms, and burrowing animals - this leads to Melanization and then aids in decomposition; Decomposition (products of littering are decomposed): fungi, bacteria, actinomycetes, soil fauna involved in decomposition; Roots/mycorrhizae of tree help with decomposition; Processes of melanization and decomposition give off carbon dioxide into the air; Decomposition and root/mycorrhizae activity lead to humification of soil; Associated processes to humification are eluviation, podzolization and illuviation; Soil organic matter: humic acid, fulvic acid, humins (these organic materials as well as the decomposition process release carbon dioxide and hydrogen carbonate ions into the soil); the mineralization of soil organic matter releases ammonium, sulfate ions, phosphate ions and nitrate ions into the soil which the tree can then take in through its roots.