The Impact of Organisms on Soil Erosion

Transcription

1 The Impact of Organisms on Soil Erosion Erosion is the movement of soil particles from one location to another. Organisms may play a huge role in the destruction of landforms through erosion. How do animals and people cause erosion? Trees, shrubs, grass, and dead leaves may cover an area. The plants are holding and protecting the soil from erosion agents such as water and wind. Removing the plants takes away the protective covering. Animals such as squirrels, moles, and gophers may borrow into the soil to create homes. By doing this, they end up bringing loosened soil to the surface. Erosion agents are able to carry away the soil. The coypu, or river rat, spends a large amount of their time in water. They feed on the plants that grow near the water. They also burrow into the soil and levees. This accelerates erosion and may even cause flooding, if the levees fail. In Louisiana, there is not a closed season on the hunting of this critter. It is hunted primarily for its fur and flesh. Insects too play a role. As tiny as they are, they make up for this by their numbers. Insects living in the top layer of the earth break soil apart. This loosens the soil. Humans may plough the soil to plant crops. Farmers have to be extra careful. When farmers till huge areas of land, if they are not careful, they could cause large areas of land to end up being eroded. During the Great Depression, poor farming practices on the Great Plains caused the Dust Bowl. Thousands of acres were ploughed. However, a huge drought followed close behind. The plants did not grow causing the land to remain bare for a long period. The plants died off. The wind blew the soil away. This caused huge problems for everyone, even people hundreds of miles away. Plants help to prevent erosion. They hold the soil together with their roots. The leaves cover soil, even when they are on the ground. This too helps to keep the soil in place. When farmers allow animals to overgraze farmland, they may remove all the leaves and roots of plants that may be helping to keep the soil in place. As the animals overfeed, they cause more of the soil to become exposed to rain and wind. Control Erosion To reduce erosion caused by ploughing, farmers are encouraged to improve their farming practices. Farmers and landowners may plant vegetation as ground cover. This ground cover will protect the soil from erosion agents. Plants that creep are great for holding and protecting the soil. Applying dead leaves and shredded wood to cover a soil is called mulching. This is a great way to reduce erosion, especially on slopes. Contour ploughing is a great way for farmers to reduce soil erosion. This is done by tilling the soil at right angles to the slope of the land. This encourages water to seep into the soil rather than flowing on the surface and carrying the soil away. The planting of wind barriers are particularly effective on wide-open areas. Wind barriers are most commonly tall trees that are planted to reduce the speed of wind. This helps to reduce wind erosion.

2 Name: Date: The Impact of Organisms on Soil Erosion 1. How may the behavior of river rats cause flooding? 2. How can squirrels and other burrowing animals cause soil erosion? 3. Why do some governments encourage people to hunt animals, such as the coypu, throughout the year? 4. How can careless farming practice cause erosion, and how did this create the Dust Bowl? 5. Gwinnett County is thinking about allowing a developer to convert a forest near the Yellow River in Lilburn, Georgia into a housing development. Quickly give one reason how this could cause erosion using the information presented to support your point. 6. Farmer Jones has a plot of land that is on a slope. He plans to plough the land to plant corn. What advice would you give to help him reduce soil erosion on his land?

3 7. How can insects contribute to soil erosion, they are so small? 8. How does contour ploughing reduce soil erosion? 9. State two farming practices that farmers may use to reduce soil erosion? 10. How can planting tall trees reduce soil erosion?

4 Name: Date: The Impact of Organisms on Soil Erosion 1. How may the behavior of river rats cause flooding? They dig up soil and levees which can cause erosion 2. How can squirrels and other burrowing animals cause soil erosion? They loosen the soil and it can be easily washed away 3. Why do some governments encourage people to hunt animals, such as the coypu, throughout the year? To lower the coypu populations 4. How can careless farming practice cause erosion, and how did this create the Dust Bowl? Too much ploughing can lead to erosion 5. Gwinnett County is thinking about allowing a developer to convert a forest near the Yellow River in Lilburn, Georgia into a housing development. Quickly give one reason how this could cause erosion using the information presented to support your point. Cutting down all the trees can lead to erosion 6. Farmer Jones has a plot of land that is on a slope. He plans to plough the land to plant corn. What advice would you give to help him reduce soil erosion on his land? Contour ploughing helps, till at 90 degree angles. 7. How can insects contribute to soil erosion, they are so small? There are so many of them that they loosen soil

5 8. How does contour ploughing reduce soil erosion? It encourage water to be absorbed 9. State two farming practices that farmers may use to reduce soil erosion? Contour ploughing and planting wind barriers 10. How can planting tall trees reduce soil erosion? It blocks wind from blowing soil away.