CG Board Class 7 Science Soil
Fill in the Blanks:
- The biggest particles of the soil are gravel or pebbles.
- Clayey soil has the maximum property of water retention.
- Breaking up of rocks into small particles is called weathering.
- Loss of the upper fertile layer of the soil is called soil erosion.
- Sandy loamy soil is good for growing cotton.
Write true and false for the statements given below and also correct the false statements.
- The soil with humus is not fertile.
False: The soil with humus is fertile.
- Loamy soil has gravel and clay particles in it.
False: Loamy soil has sand, clay, and humus particles.
- All types of soil have the same property of water retention.
False: All types of soil do not have the same water retention property.
- Soil must be porous for a good crop.
True: Soil must be porous for a good crop.
- Plants and trees increase soil erosion.
False: Plants and trees do not increase soil erosion; they help prevent it.
Answer the following questions:
How can you prove that soil has microorganisms in it?
Soil contains microorganisms such as bacteria, algae and fungi. One can prove their presence by observing the decomposition of organic matter such as dead plants or leaves, which is facilitated by these microorganisms.
How can you stop soil from being polluted?
Soil pollution can be minimized by proper waste disposal, avoiding the excessive use of pesticides and fertilizers, preventing industrial waste discharge into the soil, and promoting afforestation to reduce erosion.
How will you test the capability of water retention in red sandy soil, red loamy soil, and black soil found in Chhattisgarh?
Perform a simple water retention test by saturating each type of soil with the same amount of water and observing how much water is retained over time. Measure moisture content at intervals to compare their water holding capacities.
What will happen if soil disappears from the earth?
If soil disappears, plant life would be severely impacted, leading to a collapse of ecosystems. This would result in the loss of food sources, disruption of the water cycle, and a decline in biodiversity, affecting all forms of life.
Which type of soil is suitable for rice crop?
Clayey and loamy soils are suitable for rice cultivation as they retain water well, which is crucial for rice paddies.
What is known as soil erosion?
Soil erosion is the process where the top layer of soil is worn away by natural forces such as wind, water, or human activities like plowing and deforestation.
