Q1: What is soil, and why is it important?
Ans: Soil is the topmost layer of the Earth, and it's essential because it supports plant growth and is home to various animals. Soil provides nutrients and a place for plants to grow, which, in turn, sustains life on Earth.
Q2: How is soil formed, and how long does it take for rocks to change into soil?
Ans: Soil is formed when big rocks break down into smaller pieces due to the action of sun, wind, and water, a process called weathering. This fine powder mixes with the remains of dead plants and animals, known as humus, to form soil. It takes millions of years for rocks to change into soil.
Q3: What are the main components of soil, and what is humus?
Ans: Soil is made up of gravel, sand, clay particles, and humus. Humus is the remains of dead plants and animals found in the soil, and it provides nutrients to plants.
Q4: What are some living organisms found in soil?
Ans: Soil contains microorganisms like bacteria and fungi. It is also home to animals like earthworms, ants, moles, snakes, and rabbits.
Q5: What are the three layers in a soil profile, and what are their characteristics?
Ans: A soil profile has three layers: topsoil, subsoil, and bedrock. Topsoil is the most fertile layer, containing sand, clay, humus, air, and water. Subsoil contains pieces of rocks and less humus, and bedrock is deep inside the Earth with large rocks and little water.
Q6: What is soil erosion, and what are some causes of it?
Ans: Soil erosion is the process of topsoil being carried away by wind, water, or human activities. Causes include rainfall carrying soil, strong winds blowing away dry topsoil, deforestation, and overgrazing by cattle.
Q7: How does water cause soil erosion, and why is topsoil important?
Ans: Water causes erosion when rainwater flows over the land, carrying soil along with it. The faster the water flows, the more soil erosion it causes. Topsoil is crucial because it's the most fertile layer due to the presence of humus.
Q8: How does wind cause soil erosion, and where does it often happen?
Ans: Wind can blow away dry topsoil, especially in places with few plants, like deserts or semi-deserts. The harder the wind blows, the more soil it can carry.
Q9: What are some ways to conserve soil, and why is it important?
Ans: Soil conservation is essential to protect soil, which takes a long time to form. Methods include afforestation (planting trees), step farming in hilly areas, keeping bare soil covered after harvesting crops, and building embankments along riverbanks.
Q10: Why is afforestation an effective method of soil conservation, and how do trees help prevent soil erosion?
Ans: Afforestation is effective because trees and plants bind the soil with their roots, preventing it from being carried away by wind or water. They offer the best protection against soil erosion by stabilizing the soil with their roots.
43 videos|198 docs|45 tests
|
|
Explore Courses for Class 5 exam
|