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Climatic Geomorphology
incision. Climate changes with a tendency towards greater aridity (Antevs, 1952; Leopold,
1976, 1994) and rainfall of elevated intensity and low frequency have been identified
as important. The decrease in percentage vegetation cover in semi-arid regions, due to
overgrazing and construction work such as the building of communication routes, is one of
the fundamental causes of incision. The colonization of the western USA constitutes one
of the most significant and most studied examples (Cooke and Reeves, 1976). The
decrease in vegetation cover, combined with important storms, was the cause of some
gullies incising more than 50 m. This erosive process took place between 1850 and 1920,
especially during the period 1870 to 1890, and as a result of this new environmental
problem many of the colonists were forced to move on to more favourable areas.
Climatic Geomorphology
incision. Climate changes with a tendency towards greater aridity (Antevs, 1952; Leopold,
1976, 1994) and rainfall of elevated intensity and low frequency have been identified
as important. The decrease in percentage vegetation cover in semi-arid regions, due to
overgrazing and construction work such as the building of communication routes, is one of
the fundamental causes of incision. The colonization of the western USA constitutes one
of the most significant and most studied examples (Cooke and Reeves, 1976). The
decrease in vegetation cover, combined with important storms, was the cause of some
gullies incising more than 50 m. This erosive process took place between 1850 and 1920,
especially during the period 1870 to 1890, and as a result of this new environmental
problem many of the colonists were forced to move on to more favourable areas.