Environmental Studies ยท Biology

Soil Science and Fertilizers

1,509 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

Soil fertility is reduced by

  1. decaying organic matter

  2. crop rotation

  3. addition of N2 fixing bacteria

  4. intensive agriculture
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Intensive agriculture, which involves continuous cropping without adequate replenishment of nutrients or rest periods, leads to soil exhaustion and reduced fertility over time.

Multiple choice

Vesicular arbuscular mycorrhizae are important in

  1. nitrate nutrition of plants

  2. phosphate nutrition of plants

  3. carbonate nutrition of plants

  4. sulphate nutrition of plants
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Vesicular arbuscular mycorrhizae (VAM) form symbiotic associations with plant roots and significantly enhance the uptake of immobile nutrients, particularly phosphorus.

Multiple choice

Plant-derived compounds are responsible for providing the additional carbon that allows the rhizosphere to host such a large variety of microorganisms. Which of the following plant products are the result of abrasive forces of the root against soil particulate matter that remove cells from the root cap?

  1. Mucilages

  2. Mucigels

  3. Exudates

  4. Secretions
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mucilages are the result of abrasive forces of the root against soil particulate matter that remove cells from the root cap. Mucilages are polar glycoproteins and exopolysaccharides.

Multiple choice

Selaginella depends for fertilization on

  1. air

  2. soil

  3. water

  4. sugar
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Like many pteridophytes, Selaginella requires water for the motile sperm to swim from the antheridium to the archegonium for fertilization.

Multiple choice

Presence of phosphorus in a plant

  1. brings about healthy root growth

  2. promotes fruit ripening

  3. retards protein formation

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

Phosphorus is a critical component of ATP, nucleic acids, and phospholipids. It is well known for promoting vigorous root development in plants.

Multiple choice

The plant ash is/are the

  1. mineral salts absorbed by the plant

  2. organic matter of the plant

  3. both the mineral salts and organic matter

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

When a plant is incinerated, the organic matter (carbon, hydrogen, oxygen, nitrogen) is oxidized and lost as gases. The remaining ash consists of the inorganic mineral salts that were absorbed from the soil.

Multiple choice

In water-logged soil, plants do not grow properly because

  1. the soil is physiologically dry

  2. the soil is physiologically wet

  3. of excessive water

  4. of shortage of minerals
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The raised water table results in the soils becoming water-logged. When soils are water-logged, air spaces in the soil are filled with water, and plant roots essentially suffocate - lack oxygen. Waterlogging also damages soil structure. So, the soil becomes physiologically dry.

Multiple choice

Dried ______ is used as manure

  1. Sludge

  2. Waste water

  3. Bacteria

  4. Algae
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Sludge is a semi-solid slurry and can be produced as sewage sludge from wastewater treatment processes or as a settled suspension obtained from conventional drinking water treatment and numerous other industrial processes.

Multiple choice

How do the organisms living in the soil breathe?

  1. They use the nitrogen from the soil.

  2. They use the carbon dioxide from the soil.

  3. They use the oxygen from the air trapped in the pockets of the soil.

  4. They use the water vapours from the soil.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

They use the oxygen from the air trapped in the pockets of the soil.