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Concept of Cycle of Erosion (Davision Concept)
The cycle of erosion is a model for erosion and landscape development, proposed by William
Davis.
He defined Youth stage, Mature stage, and Old stages in the development of river valleys and
the landscape (the rivers were eroding).
The cycle of erosion, has its initial stage at a time when the landmass is rapidly elevated by
internal earth forces, followed by a very long period of tectonic quiescence. Once raised high
above sea level as a landmass, streams come into existence and erosion begins to operate on
the uplifted mass which is gradually worn down almost to a plain.
In a normal cycle three stages have been recognized as:
1. youth stage
2. mature stage and
3. Old stage.
These follow each other in a regular sequence.
Youth Stage
In this stage the river flows along an uneven surface and there is intensive bottom erosion, the
gradients are steep and the erosion is rapid. The rapid deepening of the channel leads to the
formation of V-shaped valleys. Thus during the youth stage of a river, the valley form undergoes
vigorous development, particularly in depth and head ward growth. Waterfalls and steep-sided
valleys are of common occurrence during this stage.
Mature Stage
In this stage rivers attain a profile of equilibrium. The land mass is fully dissected and a well-
integrated drainage system is developed. Ridges and valleys develop prominently. Flood plains
develop and river meandering takes place.
Old Stage
In this stage the slope is gentle and the velocity is low. The river loses most of its erosive power
and flow is slow. In old age a river has maximum meandering. The river at this age does little of
erosion and transportation but is mostly engaged in deposition. This stage is characterized by
the development of distributaries.
Most of the cycles of erosion do not reach the final stage, as sometime during their operation
either climatic or tectonic disturbances take place, and thus results in an incomplete or partial
cycle
