Practice exam #3 - QUESTION 1

a) Additions, Translocations, Transformations, Losses. b) Additions: Addition of organic residues, addition of chemical fertilizer, addition of acids through acid rain, addition of salts from salty groundwater percolating into the soil.

  Translocations: Eluviation, illuviation (of clay, Fe/Al oxides/humic substances), mixing of organic and mineral horizons due to churning, argillipedoturbation, cryoturbation.
 Transformations: Oxidation, reduction, decomposition of organic residues, weathering of parent material and primary minerals, mineralization, immobilization, chelating.
Losses: Harvesting, leaching of water-soluble nutrients, gaseous losses such as denitrification, erosion.

c) Regosolic order: dominant soil forming process is either the recent addition of a layer of sediment, or the recent loss of a large amount of the soil profile.

  Brunisolic order: Translocation (leaching) of soluble salts and carbonates.
  Luvisolic order: Translocation (illuviation) of Bt horizons with clay-fraction primary particles.
  Gleysolic order: Reduction (transformations) of Fe compounds in anaerobic conditions (some oxidation at mottles)
  Chernozemic order: Mixing (translocation) of humic compounds from organic horizon to mineral horizons
 Solonetzic order: Accumulation of salts (especially Na+) from parent material (Addition?).
 Podzolic order: Illuviation (translocation) of B horizon with Fe/Al oxides.
Organic order: Decomposition (transformation) of organic residues into humic substances.
Cryosolic order: Cryoturbation (translocation).
Vertisolic order: Argillipedoturbation (translocation)

Think about the diagnostic horizons Blaise to help you identify the dominant soil forming process