Gradation is the process by which the earth’s
surface gets leveled. It can be further divided into degradation, the process
of eroding the earth’s elevated surface and aggradations, the process of
filling up the earth’s depressions.
The forces which act on the surface of the earth
are termed as Gradational agents. Water, wave, wind, ice are the important
gradational agents. Let us now discuss the gradiational agents one by one.