Humus

Q.

The maximum amount of humus is found in _______.

1. B horizon
2. C Horizon
3. A horizon
4. Bedrock

Q.

What is the importance of humus?

1. Determines soil fertility

2. Determines percolation rate

3. Determines soil texture

4. Determines soil colour

Q. Which of the following organisms makes the soil porous?

1. Scorpions
2. Snakes
3. Beetles
4. Earthworms

Q.

The layer of soil which is not rich in humus but rich in minerals is ___ .

Q.

When a sample of soil is mixed with some water inside a beaker, the upper layer of soil always floats on top. This layer is called humus. What is it composed of?

1. Light clay particles

2. Small rocks

3. Dead remains of plants and animals

4. Sand particles

Q. What is humus? How is it helpful for plants? [2 MARKS]

Q.

How does detritus give rise to humus?

Q.

Soil profile is a vertical section of the different layers which make up soil.

1. True

2. False

Q.

Micro-organisms act upon the dead plants to produce (i) sand (ii) mushrooms (iii) humus (iv) wood

1. sand

2. mushrooms

3. humus

4. wood

Q.

The quality of the soil is decided by:

1. amount of humus

2. microscopic organisms

3. both (a) and (b)

4. none of these

Q.

Answer the following: [3 MARKS]

i. Define soil profile.

ii. _______ is the process by which soil is formed.

iii. Water drains quickest through ___ soil.

Q. The four main components of soil are

(a) tiny pieces of rock, humus, air and sand
(b) humus, clay, water and salts
(c) air, water, tiny pieces of rock and manure
(d) tiny pieces of rock, air water and humus

Q.

The section of soil profile that is composed of dead and rotting remains of living plants and organisms is known as ___.

Q.

Which of the following options defines humus?

1. Sand particles

2. Dead, decaying organic matter

3. Plastic particles

4. Decaying inorganic matter

Q.

What is the importance of humus?

1. Determines soil fertility

2. Determines soil colour

3. Determines percolation rate

4. Determines soil texture

Q.

Which of the following options are wrong regarding humus.

1. Humus stabilizes the texture of the soil.

2. Humus reduces the soil fertility.

3. Humus enhances the soil fertility.

4. Humus promotes air and water circulation in soil.

Q. Which of the following organisms makes the soil porous?

1. Scorpions
2. Snakes
3. Beetles
4. Earthworms

Q.

What organic material is formed from decaying leaves and other plant material?

1. Sand

2. Humus

3. Rocks

4. Gravel

Q.

What is the importance of humus?

1. Determines soil texture

2. Determines soil colour

3. Determines soil fertility

4. Determines percolation rate

Q. Fertile agricultural soil appears deep coloured at the surface as compared to the colour one metre down. The reason for the colour of topsoil is due to:

1. Organic matter
2. Rocks
3. Fertilizers
4. Moisture