Erosion – Causes, Effects, and Prevention

Introduction:

Have you ever constructed a sandcastle at the beach? Did the sea wash it away? Waves constantly crash against the shores of oceans and lakes. They collect sand and small rocks from the beach. The pieces are then carried away.

Erosion is the movement of weathered rock. Weathering and erosion both help to shape the land.

There are many features on the earth’s surface such as mountains, hills, plains, waterfalls, etc. These features are called landforms.

There are many factors such as wind, water, chemicals, and depositions that shape the land.

Various shapes of rock on Earth are formed by weathering and erosion.

What is Erosion?

You studied that weathering degrades rocks. But what happens to weathered rocks after that? Have you ever observed a river flowing? You may have noticed sediments and small rocks being carried by flowing water. Weathered rock is comprised of these sediments and small rocks.

Erosion is the movement of weathered rock. Weathering and erosion interact to shape and change the land.

Factors Affecting Erosion

Some soils and rocks erode more quickly than others. For example, sandy soil is more easily blown or washed away than hard-packed clay.

The size of sediments also has an impact on erosion. Sand, for example, is more easily blown or washed away than pebbles.

The rate of erosion is also affected by the strength of the wind and water.

Erosion is accelerated by floods, heavy rains, and strong winds.

Plants also have an impact on how quickly soil erodes.

Flowing Water

The most significant cause of erosion is flowing water. Sediments are carried into streams and rivers by rainwater. The moving water then flows downhill, carrying the sediments with it. The sediments are eventually deposited in a new location.

Erosion is also caused by waves. First, the waves separate the rocks. The waves then transport the rocks and sand to a new location.

Wind

Small pieces of rock, sand, and soil are picked up by the wind. It then transports them to other locations. This is the cause the wind erosion. In the meantime, abrasion from the wind weathers the rock.

Dropping Off Sediments

Wind or water picks up and transports bits of rock, sand, and soil. They are then dropped off. Deposition is the process by which weathered rock falls to the ground. Sediments are deposited along the banks and sides of rivers and streams. Many of the finer sediments reach river mouths or ends. They are deposited in large quantities there. Winds can also pick up sand and soil and deposit it hundreds of miles away.

Severe Erosion

Farmers in some states farmed many acres of land during the 1920s. Harvests were plentiful at first. The soil became overused after only a few years. The drought began in 1930. For nearly ten years, there was little rain. Crops would fail to grow. The soil had become bare and exposed to high winds. The dry soil began to blow away because there were no plants to hold it in place. After this occurrence, this event was named as Dust Bowl.

A horrible dust storm took place. For miles, thick, black clouds of dust swirled around. The dust storms were dubbed “black blizzards.”

The wind blew dry soil everywhere. It found its way into the cracks of houses. It accumulated in closets and on dishes. In some places, up to 30 cm (12 in.) of soil was lost.

Effects of Dust Bowl

The Dust Bowl had disastrous consequences. Many animals suffered and died because there were no plants to eat. Thousands of farmers were compelled to leave their homes. They were compelled to relocate west in search of a better life.

Methods to Control Soil Erosion

The Dust Bowl taught people the value of soil conservation. Soil conservation entails using methods to save it and slow erosion. Farmers now use methods to do it.

To slow wind erosion, they plant trees between fields.

Crops are also planted in strips. Plants are used in one strip to hold the soil. The following strip will be planted with a food crop. The strips are then changed the following year. This farming method is known as strip farming.

On sloped land, another method, contour plowing, is used. Farmers plough their fields across a slope instead of up and down. The shape of the plowed land helps to prevent soil from eroding.