SOIL AND PLANT ANALYSIS (1+1)

Mechanism of aggregate formation

• The bonding of the soil particles into structural unit is called as the genesis of soil structure.


• The bonding between individual particles in the structural units is generally considered to be stronger than the structural units themselves.


• In aggregate formation, a number of primary particles such as sand, silt and clay are brought together by the cementing or binding effect of soil colloids.


• The cementing materials taking part in aggregate formation are colloidal clay, iron and aluminium hydroxides and decomposing organic matter.


• Whatever may be the cementing material, it is ultimately the dehydration of colloidal matter accompanied with pressure that completes the process of aggregation.