water run through them into the ground because they are hard andimpermeable(Figure
19.7). Since the water cannot enter the ground, it then runs over the ground faster than
usual. This can speed up water erosion.
Figure19.7: Urbanareasandparkinglotsresultinlesswaterenteringtheground. Therefore,
more water runs over the land and quickly forms channels that can speed up erosion. ( 6 )
Humans also cause erosion through recreational activities, like hiking and riding off-road
vehicles. An even greater amount of erosion occurs when people drive off-road vehicles over
an area. The area eventually develops bare spots where no plants can grow. Erosion becomes
a serious problem in these areas.
Human-caused Erosion
Some erosion is a natural process and has always happened on Earth. However, human
activities like those discussed above, have accelerated soil erosion, which may occur about 10
times faster than its natural rate. As the human population grows, we increase our impact
on soil erosion. In order to support Earth’s human population, we need to create more and
more farmland, we develop more areas and build more cities, and we use much more of
the land for recreation. Human population growth can lead to degradation of the natural
environment.
Human impact on erosion differs throughout the world. In developed countries like the
United States, we have learned good agricultural practices that greatly slow down agricul-
ture’s impact on erosion. However, we still experience much erosion from the development
of urban areas and construction of new cities. In developing countries, many people are very
poor and just want to be able to grow food and make a simple living. They carry out slash