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Roger Weller, geology instructor
by Jessica Redus
What is soil?
Soil is a body with layers (horizons) made of anything from leaves to rock particles. The four main layers are O, A, B, and C. The O horizon is made up of things like leaves and litter. It is really anything on top of the surface. Horizon A is made up of decomposed organic matter and is also known as top soil. It is typically very dark due to these organic materials. Horizon B is a layer consisting of clay and iron oxides and is also called the zone of accumulation because things from the A horizon that eventually settle down into this horizon. Horizon C is the last layer of the four; it is made up of particles of rocks.
What is erosion?
Erosion is a mechanical process that makes something wear by grinding it down. Thus; soil erosion is the breaking down and wearing out of soil. Soil erosion is a natural process within the environment, however; certain things have caused the Earthís soil to erode at an alarming rate. Sometimes soil erosion can be beneficial to ecosystems at times but for the most part it is harmful and destructive to the environment.
What causes soil erosion?
Many things can cause soil erosion. The main factor isnít so much weathering as it is humans. Humans and other animals have been increasing the soil erosion around the world. The main causes of soil erosion I will be covering are: wind, water, ice, fire, gravity, animals, and, of course, humans.