OF SOILS BASED ON COMPOSITION
A) Organic soil - contain 20% or more organic matter
muck soil - contains 20-65% organic
B) Mineral soil (field soil) - contains less than 20% organic matter.
4 Major Components (in a well watered, but well drained loam soil)
1) air- approximately 25% of volume; in larger pores
2) water - approximately 25% of volume; in smaller pores
- 44-49% of volume
matter - typically about 1% in nature
litter - partially decayed organic matter on the soil surface.
humus - highly decomposed, fine, amorphous organic matter in the soil.
Functions of Organic Matter: