Question

How can tree planting prevent soil erosion?

Answer 1

Hint: Soil erosion is actually degradation of the upper layer of soil. This layer is the most fertile layer. It is a natural process and it can occur due to various reasons like overfarming, overgrazing, etc.

Complete answer:
Soil is a material which is composed of five ingredients. These ingredients are minerals, soil organic matter, living organisms, gas, and water. Depending on the percentages of particles soil minerals are broadly divided into three size classes. These classes are clay, silt, and sand. The mineralogy and textures of soils are diverse. Soil textures dependent on topology, geographical conditions, climate, temperature and human activities. Soil plays importance in mineral balance, agriculture and proper functioning of the food chain. It is the starting point of the food chain as plants grow only in fertile soils with adequate mineral depositions.

Soil erosion is a gradual process of movement of the upper layer of soil by different agents like water, wind, and mass movement. Soil erosion is the removal of the most fertile top layer of soil through water and wind. Soil erosion is also enhanced by human activities like deforestation.This causes deterioration of soil quality in the long term. Soil erosion has a specific definition as it has serious impacts on the quantity and quality of soil ecosystems.
More than half of the topsoil on earth has been lost in the last 150 years. Main causes of soil erosions are deforestation- clearing of trees for more land for human activities, overgrazing- caused by intensive cattle rearing, agrochemicals- used for agriculture deteriorate the quality of soil and construction and other recreational activities.

Planting more trees and plants reduces soil erosion. Trees and woody vegetation are good for agricultural land. Trees reduce the effect of erosive forces using their root systems and foliage. Trees have thick root systems that branch into fine filaments and create a network. This network of root systems help stabilize the soil around the tree and hold it in place. Trees also reduce run-off of nutrients and soil sediment in-stream. Tree roots also improve the drainage of the soil. A program of afforestation involves planting of trees to prevent soil erosion and to increase the number of trees.

Note: The various methods to prevent soil erosion are,
1)Prevention of overgrazing by farm animals
2)Changing agricultural practices
3)Promote terrace farming and have frequent crop rotation
4)Ban slash and burn and till farming
5)Watering the soil and maintaining the pH of the soil