Q80. Red-yellow soil is found in which Rajasthan district?
[RPSC Executive Officer / Revenue Officer (14 May 2023, Shift 2)]
- (A) Bundi
- (B) Baran
- (C) Kota
- (D) Sawai Madhopur
Answer: (D) Sawai Madhopur
Explanation: The red-yellow soil category occurs around parts of Sawai Madhopur. Iron compounds contribute the characteristic red or yellow shades, influenced by oxidation and drainage. Distribution varies with underlying rock and local weathering, so the district association is more precise than a statewide generalization.
Q79. Which soil shows natural self-ploughing through the formation of drying cracks?
[SSC MTS 2022 Paper (11 May 2023, Shift 3)]
- (A) Red soil
- (B) Laterite soil
- (C) Peaty soil
- (D) Black soil
Answer: (D) Black soil
Explanation: Black soil expands when wetted and shrinks when dry. This shrinking creates wide, deep cracks that aerate the soil profile, earning it the description self-ploughing. The phenomenon results from expansive clay minerals rather than mechanical cultivation.
Q78. Which soil is composed of varying proportions of sand, silt and clay, contains lime and potash, and is classified by age?
[UPSC CDS General Knowledge (16 April 2023)]
- (A) Alluvial soil
- (B) Laterite soil
- (C) Arid soil
- (D) Black soil
Answer: (A) Alluvial soil
Explanation: Alluvial soils form from sediments carried and deposited by rivers. The proportions of sand, silt and clay differ by locality. Indian geography distinguishes newer khadar from older bhangar alluvium, reflecting depositional age and floodplain position.
Q77. What soil type forms most of India’s Northern Plains?
[SSC CHSL 2022 Paper (20 March 2023, Shift 4)]
- (A) Alluvial
- (B) Peaty
- (C) Black
- (D) Laterite
Answer: (A) Alluvial
Explanation: Alluvial material transported by the major northern rivers accumulated in the broad plains south of the Himalayas. These deposits vary in texture and age. Younger floodplain alluvium is khadar, while older deposits on higher surfaces are bhangar.
Q76. Which statement concerning laterite soil is incorrect?
[SSC CHSL 2022 Paper (20 March 2023, Shift 4)]
- (A) Some southern laterites suit cashew
- (B) It is normally rich in humus
- (C) Tea and coffee can be cultivated on managed laterites
- (D) It develops under high rainfall and temperature
Answer: (B) It is normally rich in humus
Explanation: Laterite soils are highly leached in humid tropical climates and are frequently poor in humus and plant nutrients. With suitable amendments, irrigation and management, certain lateritic regions support tea, coffee and cashew cultivation despite their natural low fertility.
Q75. Assess two claims: I. Forest soils may be loamy and silty along valley sides. II. Black soils tend to be phosphorus-deficient.
[SSC CHSL 2022 Paper (14 March 2023, Shift 4)]
- (A) Both I and II
- (B) Only I
- (C) Only II
- (D) Neither I nor II
Answer: (A) Both I and II
Explanation: Forest soils differ with altitude and slope, and valley sides may develop loamy or silty textures. Deccan black soils contain substantial clay and mineral bases but commonly lack phosphorus. Both statements are therefore consistent with standard Indian soil descriptions.
Q74. Which soil-forming factor was identified in the paper as determining the accumulation and mineral character of soil?
[SSC CHSL 2022 Paper (14 March 2023, Shift 1)]
- (A) Fauna
- (B) Flora
- (C) Parent rock
- (D) Relief
Answer: (C) Parent rock
Explanation: Parent material provides the original mineral constituents from which a soil develops, influencing texture, chemistry and colour. Relief, climate and living organisms also affect soil formation, but the composition of the underlying rock provides the initial mineral framework.
Q73. Two statements say sandy soil has more fine particles and clayey soil more large particles. Which is correct?
[SSC CHSL 2022 Paper (13 March 2023, Shift 4)]
- (A) Only the sandy-soil statement
- (B) Neither statement
- (C) Both statements
- (D) Only the clayey-soil statement
Answer: (B) Neither statement
Explanation: Sand consists of relatively coarse mineral grains, whereas clay particles are extremely fine. Thus, both proposed associations reverse the actual particle-size relationship. Particle size greatly influences infiltration, aeration and water retention in agricultural soils.
Q72. What is the name of the exceptionally porous belt at the Shivalik foothills where streams commonly disappear underground?
[RPSC Senior Teacher Grade II GK (12 February 2023, Shift 1)]
- (A) Bhabhar
- (B) Tarai
- (C) Dhands
- (D) Dhoros
Answer: (A) Bhabhar
Explanation: The Bhabhar belt is made of coarse gravelly alluvium laid down by streams descending from the Shivaliks. Water infiltrates its large pores, making many channels disappear temporarily. Streams often re-emerge farther south in the wetter, finer-textured Tarai zone.
Q71. In which city is the Indian Institute of Soil Science located?
[SSC CGL Tier I (12 December 2022, Shift 3)]
- (A) Porbandar
- (B) Bhopal
- (C) Visakhapatnam
- (D) Bhubaneswar
Answer: (B) Bhopal
Explanation: The Indian Institute of Soil Science is located in Bhopal, Madhya Pradesh, and operates within the ICAR system. Its work supports research into soil management, crop nutrition and fertility. It should not be confused with soil-salinity research facilities at Karnal.
