Degradation mechanisms humus

In soil the most widespread mineral is quartz, feldspar and mica flakes thongh calcite and gypsmn are present occasionally. Also there are important aecnmnlations of kaolinite, zeolite and montmorillonite etc. Characterization of soil indicates its mechanical composition, i.e., the size of grains in it. The size of particles determines the varions names of soil thns there are stony, silty, sandy soils. In soil, oiganic matter is usually represented by hnmns, which consists of stable humic degradation matter, and their type depends on the plants from which it forms. Due to presence of humus in soil, varions tint of grey, brown and black colonrs are attributed. Type and quantity of humus may... 

---