Environmental Studies · Biology

Soil Science and Fertilizers

1,537 Questions

Soil science focuses on soil formation, classification, and fertility management using fertilizers and organic amendments. Agricultural and environmental science exams heavily feature questions on biofertilizers, mycorrhiza, and phytoremediation. Practice these questions to build a strong understanding of soil nutrient cycles.

Phytoremediation techniquesOrganic soil amendmentsBiofertilizers and mycorrhizaNitrous oxide emissionsIn-situ soil remediationGreen manuring effects

Soil Science and Fertilizers Questions

Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

The rotting dead matter in the soil is called as

  1. Decomposition

  2. Humus

  3. Petrification

  4. Minerals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The dark black upper layer of soil is known as humus. It is actually the dead matter of plants and animals that have been decomposed by bacteria and fungi. This humus rich soil increases the aeration capacity of soil and also helps in the penetration of roots of plants. The decomposition of organic matter helps in bringing the plant and animal residues back to soil. The soil organisms use the organic matter its food and in the process convert in into nutrient rich humus for plant growth. 

Thus, the correct answer is option B. 

Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

Which of the following provides nutrients and makes the soil fertile?

  1. Gravel

  2. Humus

  3. Clay

  4. Loam
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Decomposers are organisms that feed on plant and animal dead bodies. They convert their complex material into simpler materials. These simple materials are stored in the form of humus, which is a dark-coloured material present in the soil. 

Humus contains decomposed leaf litter and animal waste. It is very rich in nutrients. So, it makes the soil fertile.
Thus, option B "Humus" is the correct option.

Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

Pure clay is not suitable for plant growth because

  1. It is chemically inert

  2. It is chemically active

  3. It forms a solid non penetrable mass

  4. All of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Clay soil is soil that contains a high percentage of clay particles. It is slow to drain water and quick to harden leading to water logging. It blocks root absorption, which prevents plants from getting nutrients required for survival. Hence it is not suitable for plant growth. Thus the correct answer is option C.

Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

Why is organic matter (humus) an important part of soil?

  1. It helps to improve water infiltration

  2. It can break down organic pollutants

  3. It converts nitrogen in the air into nitrates used by plants

  4. It is rich in nutrients, which is important for fertility
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Humus controls and regulates many soil functions, as well as plant growth. The better the humus count in the soil, the healthier and more productive soil will be. Regardless of the program one uses in farming operations, the higher the humus count, the better the crop is grown yield. Good humus count in the soil will hold soil moisture longer, thus less water is required for crop production. Also, good humus count reduces both water and wind erosion of soil.

Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

Humus is defined as

  1. Physical texture of soil

  2. Chemical composition of soil

  3. Decomposed organic matter in soil

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Humus is the dark, organic material that forms in soil when plant and animal matter decays. It is a crucial component for soil fertility.

Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

'X' is an organic substance obtained from the decomposition of plant or animals wastes which provides lots of humus to the soil. Identify the incorrect statements regarding decomposition.

  1. It makes the soil porous

  2. It reduces the water holding capacity of the soil

  3. it increase the number of friendly microbes

  4. It improves the texture of the soil
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Humus is the dark, organic material formed in the soil when plant and animal matter decays.
It is important as it retains-
1)  Moisture content in the soil.

2) Loosens the soil which allows better aeration and drainage.
3) It encourages the increase of soil organisms which help make nutrients available to plants. 
4) It makes the soil more porous.
5) High humus content increases water holding capacity of the soil.
So, the correct answer is 'It improves the texture of the soil'.

Multiple choice evs mud and stones soil - formation and profile soil-nature soil profile

Which of the following characteristics is not a function of humus in soil?

  1. Provides nutrients

  2. Raises pH

  3. Retains moisture

  4. Humus does all of the above in soil
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Explanation: Humus is the end product of broken down (decayed) organic matter. Humus is an essential component of healthy soils that has many great benefits.

Multiple choice chemistry for a pollution free nature properties of soil soil pollution and its effects soil and soil pollution

Reducing chemical fertilizer and pesticide use controls _______.

  1. soil pollution

  2. global warming

  3. both of them

  4. none of above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Applying bio-fertilizers and manures can reduce chemical fertilizer and pesticide use. Biological methods of pest control can also reduce the use of pesticides and thereby minimize soil pollution.

Multiple choice chemistry for a pollution free nature properties of soil soil pollution and its effects soil and soil pollution

Pesticides and fertilizers should be applied on croplands only in limited amounts because it helps in control of ______.

  1. soil pollution

  2. water pollution

  3. thermal pollution

  4. all of above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pesticides and fertilizers should be applied on croplands only in recommended dose, prescribed by Indian Standard Institution experts. It will help in reducing the level of water and soil pollution caused through these chemicals.

Multiple choice chemistry for a pollution free nature properties of soil soil pollution and its effects soil and soil pollution

Which chemical compound is responsible for making soil infertile?

  1. Fertilizers

  2. Germicides

  3. Verbicides

  4. All of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Fertilizers are the chemical compound which is used in agricultural land to increase the fertility of soil. The use of fertilizers for long time makes the upper layer harder and renders the soil infertile.

Multiple choice chemistry for a pollution free nature properties of soil soil pollution and its effects soil and soil pollution

Which type of biological waste effect soil?

  1. Urine

  2. Feces

  3. Both a and b

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Every human produces a certain amount of personal waste products by way or urine and feces. While much of it moves into the sewer the system, there is also a large amount that is dumped directly into landfills in the form of diapers. Even the sewer system ends at the landfill, where the biological waste pollutes the soil.