Environmental Studies · 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

Salinization occurs when the irrigation water accumulated in the soil evaporates, leaving behind salts and minerals. What are the effects of salinization on the irrigated land?

  1. It greatly increases the crop production.

  2. It makes some soils impermeable.

  3. It raises the water table.

  4. It fills the air spaces in the soil with water.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Salinization is a process that results from:  High levels of salt in the soils  Landscape features allow salts to become mobile (Movement of water table).  Climatic trends favour accumulation.  Human activities such as land clearing, aquaculture activities, irrigation, and the salting of icy roads The consequences of salinity are  � salt makes some soils impermeable that have detrimental effects on plant growth and yield  � damage to infrastructure (roads, bricks, corrosion of pipes and cables)  � reduction of water quality for users, sedimentation problems  � soil erosion ultimately, when crops are too strongly affected by the amounts of salts.  Salinity is an important land degradation problem. Soil salinity can be reduced by leaching soluble salts out of soil with excess irrigation water. Soil salinity control involves water table control and flushing in combination with tile drainage or another form of subsurface drainage.

Multiple choice

With reference to micro-irrigation, which of the following statements is/are correct?

  1. Fertilizer/ nutrient loss can be reduced.
  2. It is the only means of irrigation in dry land farming.
  3. In some areas of farming, receding of ground water table can be checked.

Select the correct answer using the codes given below:-

  1. 1 only

  2. 2 and 3 only

  3. 1 and 3 only

  4. 1, 2 and 3
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  1. Drip irrigation, also known as trickle irrigation or micro-irrigation, is an irrigation method which saves water and fertilizer by allowing water to drip slowly to the roots of plants, either onto the soil surface or directly onto the root zone, through a network of valves, pipes, tubing, and emitters.
    2. This method is also applicable in farms, commercial greenhouses, and residential gardens.
    1. Drip irrigation may help to achieve water conservation by reducing evaporation and deep drainage when compared to other types of irrigation.
Multiple choice

What is the significance of 'ash' in the study of mineral nutrition of plants?

  1. It indicates what minerals are present in the soil.

  2. It indicates which element is essential and in what amount it is necessary for a particular plant.

  3. It is of no practical significance.

  4. It indicates how much irrigation is needed by the plant.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ash of a plant indicates which element is essential and in what amount it is necessary for a particular plant.

Multiple choice

Plants absorb soil minerals in the form of a

  1. very dilute solution

  2. dilute solution

  3. concentrated solution

  4. highly concentrated solution
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Plants absorb soil minerals in the form of a very dilute solution. 

Multiple choice

Which of the following is not a parameter for determining the quality of soil?

  1. Amount of humus

  2. Population of microscopic organisms

  3. Nutrient content

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

Urbanisation is not a parameter for determining the quality of soil. Soil quality indicators are physical, chemical, and biological properties, processes, and characteristics that can be measured to monitor changes in the soil.

Multiple choice

What happens to tropical soils when the rainforest is cleared?

  1. The soil improves to the extent that soluble nutrients are no longer depleted by the trees

  2. There is little effect on the soil because of its depth of richness

  3. Clearing interrupts the critical nutrient cycle and leads to soil leaching

  4. The soils stabilise and become excellent for grain crops
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 When rain-forest is cleared, the humus formation almost ceases, thereby depleting soils critical nutrients. High rainfall also results into leaching of soil nutrient in the absence of tree cover.

Multiple choice

As per the fertilizer policy, which of the following is the only controlled fertilizer in India?

  1. Urea

  2. Phosphatic

  3. Gobar Khad

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

For sustained agricultural growth and to promote balanced nutrient application, it is imperative that fertilizers are made available to farmers at affordable prices. With this objective, urea being the only controlled fertilizer, is sold at statutory notified uniform sale price, and decontrolled Phosphatic and Potassic fertilizers are sold at indicative maximum retail prices (MRPs). The problems faced by the manufactures in earning a reasonable return on their investment with reference to controlled prices, are mitigated by providing support under the New Pricing Scheme for Urea units and the concession Scheme for decontrolled Phosphatic and Potassic fertilizers. 

Multiple choice

Choose the incorrect statement.

  1. Earthworm softens the soil.

  2. Earthworm also eats the dead leaves and plants.

  3. The droppings of earthworms fertilise the soil.

  4. Earthworm damages the crops by eating them.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Earthworms never harm the crop.