Basic Components of soils are the individual particles (sand grains, clay particles, plant fragments) that can be resolved with the optical microscope together with the fine material that is unresolved into discrete infividuals. These components form the building blocks of more complex organizations of the soil material.

Basic Mineral Components Four main groups of coarse particles can be distinguished according to their composition: 1) single mineral grains; 2) compound mineral grains or rock fragments; 3) inorganic residues of biological origin (phytoliths, shell fragments); 4) artifacts (brick fragments, pot shards, glass, or other evidence of human influence).

Basic Organic Components Organic matter in soils is very diverse due partly to the number of alteration processes that cause gradual rather than sharply defined changes to the composition. Such diversity means that it is difficult to classify organic substances rigidly into different groups. Three main groups, however, are recognized: 1) plant residues (organic and tissure residues); 2) organic fine material (cells and cell residues, amorphous organic material in which cell wall structures are not recognized); 3) organic pigments (staining of the mineral material).

This page (http://www.ces.ncsu.edu/plymouth/programs/com.html) created by
Vera MacConnell, Research Technician, I on February 4, 1998.
Last Updated on February 4, 1998.