Concept Application and Fact for Prelims Day-21 Soils

This is the Day-17 questions of the CAF Revision plan for prelims. The questions are based on the syllabus as provided in the schedule. Aspirants are requested to go through the detailed CAF strategy to understand the need of the UPSC prelims and to prepare well for the same. Attempt the questions honestly. The key answers and explanations of this test will be live at 9.00pm. The maximum time to attempt the 20 questions is 25 minutes.


Q.1) “The soil is found in the areas of heavy rainfall and high humidity, where there is a good growth of vegetation. It has rich humus and organic content to the soil. Soils are normally heavy and black in colour. At many places, they are alkaline also”. The above lines describe which of the following soils?

(a) Black Regur soil

(b) Peaty soil

(c) Forest Soil

(d) Saline Soil


Q.2) Consider the following statements.

Assertion (A): In the areas of intensive cultivation with excessive use of irrigation, especially in areas of green revolution, the fertile alluvial soils are becoming saline.

Reason (R): Excessive irrigation with dry climatic conditions promotes capillary action, which results in the deposition of salt on the top layer of the soil.

In the context of the statements above, which of these is true?

a) A and R both are true, and R is the correct explanation for A.

b) A and R both are true, and R is the NOT the correct explanation for A.

c) A is correct, R is incorrect.

d) A and R both are incorrect


Q.3) Saline soils occur in which of the following areas?

  1. Arid and semi-arid regions
  2. Waterlogged and swampy areas
  3. Deltas

Choose the correct answers from the codes given below

(a) 1 and 2

(b) 1 and 3

(c) 2 and 3

(d) 1, 2 and 3


Q.4) With respect to Red and yellow soils consider the following statements.

  1. Red soil develops on crystalline igneous rocks in areas of high rainfall in the eastern and southern part of the Deccan Plateau.
  2. The fine-grained red and yellow soils are normally fertile, whereas coarse-grained soils found in dry upland areas are poor in fertility.

Choose the correct answers from the codes given below

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) None


Q.5) Laterite soils are poor in

  1. Organic matter
  2. Nitrogen
  3. Phosphate
  4. Iron oxide and potash

Choose the correct answers from the codes given below

(a) 1, 2 and 3 only

(b) 2, 3, and 4 only

(c) 1, 2 and 4 only

(d) All the above


Q.6) Consider the following statements with respect to soils of India

Soils of India
  1. Saline soils
  2. Red and Yellow Soils
  3. Black Soils
  4. Alluvial Soils

Match the areas in the map with the list.

            A          B          C

(a)        1          2          3

(b)        2          3          4

(c)        1          2          4

(d)        2          4          3


Q.7) Which of the following soils contain calcareous concretions (Kankars)?

  1. Khadar and Bhangar soils
  2. Arid soils

Choose the correct answers from the codes given below

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) None


Q.8) Which of the following crops are grown in Arid – Desert Soils?

  1. Barley
  2. Millets
  3. Maize
  4. Pulses

Choose the correct answers from the codes given below

(a) 1, 2 and 3 only

(b) 2, 3, and 4 only

(c) 1, 2 and 4 only

(d) All the above


Q.9) With reference to agricultural soils, consider the following statements:

  1. A high content of organic matter in soil drastically reduces its water holding capacity.
  2. Soil does not play any role in the sulphur cycle.
  3. Irrigation over a period of time can contribute to the salinization of some agricultural lands.

Which of the statements given above is/are correct?

(a) 1 and 2 only

(b) 3 only

(c) 1 and 3 only

(d) 1, 2 and 3


Q.10) Consider the following statements:

The nation-wide ‘Soil Health Card Scheme’ aims at

  1. expanding the cultivable area under irrigation.
  2. enabling the banks to assess the quantum of loans to be granted to farmers on the basis of soil quality.
  3. checking the overuse of fertilizers in farmlands.

Which of the above statements is/are correct?

(a) 1 and 2 only

(b) 3 only

(c) 2 and 3 only

(d) 1,2 and 3


Q.11) Which of the following is/are the advantage/advantages of practicing drip irrigation?

  1. Reduction in weed
  2. Reduction in soil salinity
  3. Reduction in soil erosion

Select the correct answer using the code given below.

(a) 1 and 2 only

(b) 3 only

(c) 1 and 3 only

(d) None of the above is an advantage of practicing drip irrigation


Q.12) It has been found recently that the acidity of the soil increases because of

(a) Leaching away of bases

(b) Increased use of ammonia

(c) Increased use of urea

(d) Increased use of rock phosphate


Q.13) The crop which grows in alluvial soil and needs 150 cm rainfall is

(a) Wheat

(b) Rice

(c) Groundnut

(d) Sugarcane


Q.14) Why the Indian farmers plough their fields during the time interval between two crops?

(a) In order to keep the soil loose for further cultivation

(b) To increase the porosity of the soil

(c) To escape drought

(d) To prevent clodding


Q.15) Maximum production of paddy per unit water consumption can be best achieved in a

(a) Non-porous soil

(b) Porous soil

(c) Impervious soil

(d) Soil that allows slow percolation


Q.16) “Mulching” the soil is a process whereby

(a) Big pieces of soil are broken down into smaller pieces

(b) The field is irrigated at regular intervals

(c) Transplanting of seedlings take place

(d) Loose material, dung, etc. are laid on the ground to prevent excessive evaporation or erosion of the soil.


Q.17) Micro-elements needed to increase soil fertility are

(a) Nitrogen, hydrogen and calcium

(b) Nitrogen, phosphorus and potassium

(c) Iron, calcium and potassium

(d) Manganese, copper and zinc


Q.18) The principal cause of soil damage in Punjab and Haryana is

(a) Salinity and water-logging

(b) Deforestation

(c) Ravine erosion

(d) Overgrazing


Q.19) Soils of Western Rajasthan have a high content of

(a) Aluminium

(b) Calcium

(c) Nitrogen

(d) Phosphorus


Q.20) Which one of the following crops enriches the nitrogen content in soil?

(a) Potato

(b) Sorghum

(c) Sunflower

(d) Pea


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