Q1. The term “soil profile” refers to:
A) The horizontal arrangement of soil types in a region
B) The vertical section of the soil showing different horizons
C) The chemical composition of soil
D) The fertility level of soil
Answer: B
Explanation: A soil profile is the vertical section of soil from the surface down to the parent material, showing all the horizons in sequence.

Q2. The layer in the soil profile that is richest in humus is:
A) A-Horizon
B) B-Horizon
C) C-Horizon
D) R-Horizon
Answer: A
Explanation: The A-Horizon or topsoil contains maximum humus and organic matter, which supports plant growth.

Q3. The B-Horizon in a soil profile is characterized by:
A) Accumulation of leached minerals like iron, clay, and aluminium
B) Maximum humus content
C) Unweathered bedrock
D) Completely devoid of minerals
Answer: A
Explanation: B-Horizon (subsoil) is the ‘zone of accumulation’ or illuviation where minerals leached from A-Horizon get deposited.

Q4. The C-Horizon mainly consists of:
A) Organic matter
B) Completely weathered rock particles
C) Partially weathered parent rock
D) Humus-rich soil
Answer: C
Explanation: C-Horizon contains partially weathered parent rock material and marks the transition between soil and unweathered bedrock.

Q5. According to ancient Indian texts, Usara land was characterized by:
A) High fertility and deep black color
B) Presence of salts making it unfit for cultivation
C) Location near perennial rivers
D) Seasonal waterlogging
Answer: B
Explanation: Usara is saline/alkaline land unsuitable for cultivation.

Q6. In ancient Indian agricultural classification, Urvara refers to:
A) Saline or alkaline land
B) Fertile, productive land suitable for cultivation
C) Desert soil
D) Rocky wasteland
Answer: B
Explanation: Urvara is fertile, cultivable land rich in nutrients and moisture, suitable for a wide range of crops.

Q7. Which of the following statements is/are correct?
1. Urvara soils are naturally suitable for agriculture without much human intervention.
2. Usara soils are generally saline or alkaline and need reclamation.
A) 1 only
B) 2 only
C) Both 1 and 2
D) Neither 1 nor 2
Answer: C
Explanation: Both statements are correct — fertility defines Urvara, while salinity/alkalinity defines Usara.

Q8. With reference to the Soil Survey of India (SSI), consider the following statements:
1. It was established in 1956 under the Ministry of Agriculture.
2. Its primary mandate is to conduct soil resource mapping and land capability classification.
3. It functions under the Department of Agricultural Research and Education.
Which of the statements given above is/are correct?
A) 1 and 2 only
B) 2 and 3 only
C) 1 only
D) 1, 2 and 3
Answer: A
Explanation:
• Statement 1 Correct — SSI was set up in 1956 under the Ministry of Agriculture.
• Statement 2 Correct — Its main job is soil resource mapping, classification, and evaluation.
• Statement 3 Incorrect — It works under the Department of Agriculture, Cooperation & Farmers’ Welfare, not the Department of Agricultural Research and Education

Q9. ICAR was originally established in 1929 as:
A) Indian Council of Agricultural Research
B) Imperial Council of Agricultural Research
C) National Agricultural Research Institute
D) Indian Agricultural Research Foundation
Answer: B
Explanation: ICAR was founded in 1929 as the Imperial Council of Agricultural Research and renamed Indian Council of Agricultural Research in 1946.

Q10. Consider the following statements about ICAR:
1. It is an autonomous organization under the Ministry of Agriculture & Farmers’ Welfare.
2. It manages both research institutes and agricultural universities.
3. It is the apex body for agricultural education, research, and extension in India.
Which of the statements given above is/are correct?
A) 1 and 2 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2, and 3
Answer: D
Explanation: All three statements are correct — ICAR is autonomous, manages both research and education institutions, and is India’s top agricultural research body.

Alluvial Soil
Q11. The texture of alluvial soils ranges from:
A) Sandy to clayey, often loamy
B) Pure clay only
C) Silty clay only
D) Peaty
Answer: A) Sandy to clayey, often loamy
Explanation: Upper courses often sandy; lower courses more clayey; loam is highly productive.

Q12. Alluvial soils in India are mainly formed by:
A) Weathering of basalt
B) Deposition by rivers
C) Leaching in high rainfall areas
D) Wind deposition
Answer: B) Deposition by rivers
Explanation: Alluvial soils are transported and deposited by rivers, especially in the Indo–Gangetic–Brahmaputra plain,

Q13. Which of the following is not a characteristic of alluvial soil?
A) High fertility
B) Rich in potash
C) High humus content
D) High nitrogen content naturally
Answer: D) High nitrogen content naturally
Explanation: Alluvial soils are generally poor in nitrogen but rich in potash.

Q14. Which mineral is generally found deficient in alluvial soils?
A) Phosphorus
B) Potash
C) Calcium
D) Magnesium
Answer: A) Phosphorus
Explanation: Alluvial soils are rich in potash but generally deficient in nitrogen and phosphorus.

Q15. Khadar soils are:
A) Older alluvium, less fertile
B) Newer alluvium, more fertile
C) Black cotton soils
D) Sandy desert soils
Answer: B) Newer alluvium, more fertile
Explanation: Khadar is deposited annually during floods, fine-textured and nutrient-rich.

Q16. Bhangar soil refers to:
A) New alluvium deposited by rivers during floods
B) Old alluvium found on higher terraces
C) Soil formed from basaltic lava
D) Soil deposited by glaciers
Answer: B) Old alluvium found on higher terraces
Explanation: Bhangar is older alluvium deposited away from the active floodplains, usually at a higher level than Khadar.

Q17. Which of the following is NOT a characteristic of Bangar soil?
A) Coarser texture
B) Rich in kankar nodules
C) More fertile than Khadar
D) Found above the floodplain level
Answer: C) More fertile than Khadar
Explanation: Bangar is generally less fertile than Khadar because it is older and contains lime nodules, reducing its productivity.

Q18. Which of the following statements is correct?
A) Khadar soils have more kankar nodules than Bangar
B) Bhangar soils are renewed annually
C) Khadar soils are lighter in color and more suitable for intensive farming
D) Bangar soils are generally found in lower floodplains
Answer: C) Khadar soils are lighter in color and more suitable for intensive farming
Explanation: Khadar is sandy loam to clay loam, lighter in texture, and very fertile.

Q19. Which of the following is a characteristic of calcareous alluvial soils?
A) High organic matter
B) Presence of kankar nodules
C) High acidity
D) Red color due to iron oxide
Answer: B) Presence of kankar nodules

Black Soil
Q20. Black soil is rich in which of the following nutrients?
A) Nitrogen and phosphorus
B) lime, iron, magnesia, alumina, potash
C) Sulphur and magnesium
D) Sodium and chlorine
Answer: B) lime, iron, magnesia and alumina.

Q21. Which of the following nutrients is generally deficient in black soils?
A. Nitrogen, Phosphorus, and Organic matter
B. Potash
C. Calcium carbonate
D. Iron
Answer: A
Explanation: Black soils are rich in lime, iron, magnesium, and potash but are generally deficient in nitrogen, phosphorus, and organic matter.

Q22. Which of the following statements about black soils is NOT correct?
A. They are formed from basaltic rocks
B. They are rich in lime and potash
C. They are highly acidic in nature
D. They show swelling and shrinking property
Answer: C
Explanation: Black soils are generally neutral to slightly alkaline, not highly acidic.

Q23. In which type of soil would you expect the slowest rate of water infiltration?
A. Black soil
B. Red soil
C. Laterite soil
D. Alluvial soil
Answer: A
Explanation: Due to its fine texture and high clay content, black soil has very slow permeability, though it retains water well.

Q24. Which of the following is a distinct physical property of black soil in India?
A. It becomes loose and sandy during the dry season
B. It cracks deeply in the dry season and swells when wet
C. It turns red after prolonged exposure to sunlight
D. It forms a hard crust on top during rainfall
Answer: B
Explanation: Black soils expand on wetting and shrink on drying, developing deep cracks that help in aeration.

Q25. The high moisture-retention capacity of black soil is primarily due to:
A. High sand content
B. High clay content
C. High organic matter
D. High lime content
Answer: B

Q26. In India, black soils are most extensive in which of the following river basins?
A. Ganga Basin
B. Narmada and Tapi Basins
C. Brahmaputra Basin
D. Mahanadi Basin
Answer: B
Explanation: The deep black soils of India are found predominantly in the Deccan Plateau region, especially in the Narmada and Tapi basins, formed from basaltic lava.

Q27. Black soils are most suitable for the cultivation of which crop?
A. Wheat
B. Rice
C. Cotton
D. Tea
Answer: C
Explanation: Due to their high moisture retention, black soils are ideal for cotton cultivation. That is why they are also called “Regur” or “Cotton soils.”

Q28. Which type of soil is commonly known as self-ploughing soil?
A) Alluvial soil
B) Black soil
C) Red soil
D) Laterite soil
Answer: B) Black soil
Explanation: Black soil, also called regur soil, has high clay content. It swells when wet and shrinks upon drying, resulting in deep cracks that help in natural ploughing, hence called self-ploughing soil.

Q29. What is meant by self-ploughing soil?
A) Soil that requires frequent ploughing by farmers
B) Soil that naturally cracks and loosens during dry season aiding tillage
C) Soil formed due to human intervention
D) Soil that has poor fertility
Answer: B) Soil that naturally cracks and loosens during dry season aiding tillage

Q30. Which Indian states have the largest extent of black soil?
A. Punjab, Haryana, Rajasthan
B. Maharashtra, Madhya Pradesh, Gujarat
C. Assam, West Bengal, Odisha
D. Kerala, Tamil Nadu, Karnataka
Answer: B
Explanation: Maharashtra, Madhya Pradesh, Gujarat, and parts of Andhra Pradesh, Telangana, and Tamil Nadu have extensive black soil areas.

Red and Yellow Soil
Q31. The red colour of red and yellow soils is mainly due to:
A. Ferric oxide in a hydrated form
B. Decomposition of organic matter
C. Presence of humus and iron
D. Silica deposition
Answer: A
Explanation: The red colour is due to the presence of ferric oxide (Fe₂O₃). Yellowish tinge appears when ferric oxide is in a hydrated form.

Q32. Red and yellow soils are generally formed from the weathering of:
A. Basalt
B. Granite, gneiss, and other crystalline metamorphic rocks
C. Shale and limestone
D. Alluvial sediments
Answer: B
Explanation: These soils develop from crystalline metamorphic rocks like granite and gneiss in low rainfall areas.

Q33. The texture of red and yellow soils is generally:
A. Sandy to loamy, with poor clay content
B. Clayey with high swelling capacity
C. Peaty with high organic content
D. Alluvial with stratified layers
Answer: A
Explanation: Red and yellow soils are generally sandy to loamy, with low clay and organic content, making them porous and well-drained.

Q34. Which of the following is generally deficient in red and yellow soils?
A. Potash and lime
B. Nitrogen, phosphorus, and humus
C. Iron and aluminium
D. Calcium carbonate and silica
Answer: B
Explanation: Red and yellow soils have low nitrogen, phosphorus, and humus content, which limits fertility without fertiliser use.

Q35. Which mineral compound is primarily responsible for the red coloration in red soils?
A. Fe₂O₃ (Ferric oxide)
B. Fe₃O₄ (Magnetite)
C. Fe(OH)₃ (Hydrated ferric oxide)
D. FeSO₄ (Ferrous sulphate)
Answer: A
Explanation: The red colour is due to an abundance of ferric oxide (Fe₂O₃).

Q36. Which of the following crops is least suited for red and yellow soils without proper irrigation and fertilization?
A. Groundnut
B. Millets
C. Wheat
D. Pulses
Answer: C

Laterite soil
Q37. Laterite soils are primarily formed under which climatic conditions?
A. Hot and arid with low rainfall
B. High temperature and high rainfall
C. Cold and dry with low rainfall
D. Temperate with moderate rainfall
Answer: B

Q38. Leaching is most intense in forest soils located in:
A. Shiwalik hills
B. Eastern Himalayas
C. Rajasthan hills
D. Malwa plateau
Answer: B
Explanation: Eastern Himalayas get extremely high rainfall, leading to intense leaching.

Q39. Which two oxides are most abundant in laterite soils?
A. Calcium oxide and magnesium oxide
B. Iron oxide and aluminium oxide
C. Potassium oxide and sodium oxide
D. Silicon dioxide and manganese oxide
Answer: B
Explanation: Laterite soils are rich in ferric oxide (Fe₂O₃) and aluminium oxide (Al₂O₃) because silica and bases are leached away in heavy rainfall areas.

Q40. Which of the following nutrients is generally deficient in laterite soils?
A. Iron and aluminium
B. Potash, nitrogen, lime and silica
C. Aluminium
D. Ferric oxide
Answer: B
Explanation: Laterite soils are poor in nitrogen, potash, and lime due to intense leaching, though they are rich in iron and aluminium oxides.

Q41. The acidic nature of laterite soil is mainly due to:
A. High humus content
B. High aluminium oxide concentration
C. Loss of basic cations like calcium and potassium
D. Presence of manganese oxides
Answer: C
Explanation: Intense leaching removes basic cations (Ca²⁺, K⁺, Na⁺), making laterite soils acidic.

Q42. Laterite soil is extensively used for which non-agricultural purpose?
A. Cement manufacturing
B. Road construction
C. Brick-making and building material
D. Fertiliser production
Answer: C
Explanation: Due to its hardness when dry and ease of cutting when soft, laterite is widely used as a building material in Kerala, Karnataka, and Goa.

Q43. Laterite soils in India are most widely found in:
A. Punjab plains
B. Eastern and Western Ghats
C. Thar Desert
D. Indo-Gangetic plains
Answer: B
Explanation: Laterite soils are common along the high rainfall zones of the Eastern and Western Ghats, including hill slopes of Karnataka, Kerala, Tamil Nadu, Maharashtra, and Odisha.

Q44. Laterite soils are most suitable for which of the following crops without heavy irrigation?
A. Tea, coffee, and cashew
B. Wheat, barley, and gram
C. Rice, maize, and jute
D. Sugarcane and cotton
Answer: A
Explanation: Tea, coffee, cashew, and tapioca grow well in acidic, well-drained laterite soils with heavy rainfall.

Arid Soil
Q45. The red to brown colour of arid soil in India is due to:
A. Humus content
B. High iron oxide and low organic matter
C. Presence of calcium carbonate and soluble salts
D. Presence of manganese oxides
Answer: C
Explanation: Arid soils are pale brown to reddish-brown because of calcium carbonate and soluble salts; low humus content also contributes to the light colour.

Q46. Arid soils are generally alkaline because:
A. They are rich in humus
B. They contain high amounts of calcium carbonate and soluble salts
C. They are formed from basaltic lava
D. They have low silica content
Answer: B
Explanation: High evaporation rates cause accumulation of salts and lime, making arid soils alkaline in nature.

Q47. Which crop is best suited for cultivation in arid soils without heavy irrigation?
A. Rice
B. Bajra (Pearl millet)
C. Wheat
D. Sugarcane
Answer: B
Explanation: Bajra is drought-resistant and thrives in sandy arid soils with minimal moisture.

Q48. The presence of kankar nodules in arid soil indicates:
A. Organic matter enrichment
B. Accumulation of calcium content
C. High silica concentration
D. Leaching of minerals
Answer: B

Q49. Which of the following statements about arid soils is NOT correct?
A. They often contain kankar nodules of calcium carbonate
B. They have low water-holding capacity
C. They are generally acidic in reaction
D. They are low in organic matter
Answer: C
Explanation: Arid soils are generally alkaline, not acidic, because of the accumulation of basic salts and carbonates.

Q50. Which of the following nutrients is generally deficient in arid soils?
A. Potash
B. Nitrogen and humus
C. Calcium
D. Iron
Answer: B
Explanation: Low rainfall and sparse vegetation lead to very low organic matter, hence deficiency of nitrogen and humus.

Saline Soils
Q51. Saline soils are also known as:
A. Regur soils
B. Usara soils
C. Khadar soils
D. Pedalfer soils
Answer: B
Explanation: In India, saline/alkali soils are locally called Usara soils.

Q52. Which of the following is the primary cause of saline soil formation in arid and semi-arid regions?
A. Heavy leaching due to rainfall
B. Evaporation exceeding precipitation
C. Deposition of volcanic ash
D. High organic matter decomposition
Answer: B
Explanation: When evaporation exceeds rainfall, salts from below the soil surface are drawn upward and accumulate in the topsoil.

Q53. Which of the following salts are most common in saline soils?
A. Sodium chloride and sodium sulphate
B. Calcium carbonate and magnesium oxide
C. Potassium nitrate and ammonium sulphate
D. Aluminium chloride and ferric oxide
Answer: A
Explanation: The most common salts in saline soils are NaCl and Na₂SO₄, along with other soluble salts.

Q54. Which reclamation method is most effective for saline/alkali soils?
A. Addition of lime
B. Addition of gypsum
C. Application of organic manure only
D. Flood irrigation without drainage
Answer: B
Explanation: Gypsum (CaSO₄·2H₂O) replaces sodium ions with calcium, helping reduce alkalinity. Proper drainage is also essential.

Q55. Which of the following statements is NOT correct regarding saline soils?
A. They are found in both arid and coastal regions
B. They are poor in nitrogen and calcium
C. They often develop a whitish surface crust of salts
D. They are highly permeable to water
Answer: D
Explanation: Saline/alkali soils often have poor permeability due to the dispersing effect of sodium on soil particles, which reduces porosity.

Q56. Which of the following crops is best suited for saline soils without major reclamation?
A. Wheat
B. Cotton
C. Rice
D. Sugarcane
Answer: C
Explanation: Rice can tolerate high salinity levels, especially when grown under standing water conditions.

Q57. Coastal saline soils in India are mainly formed due to:
A. Capillary rise of groundwater
B. Sea water intrusion
C. Leaching of nutrients
D. Volcanic activity
Answer: B
Explanation: Sea water intrusion during tides and storm surges leads to high salt content in coastal saline soils.

Q58. Which of the following regions is NOT a major saline soil area?
A. Rann of Kachchh
B. Sunderban delta
C. Western Rajasthan
D. Malwa Plateau
Answer: D
Explanation: Malwa Plateau is dominated by black soils, not saline soils.

Q59. In inland regions of India, saline soils are mainly formed due to:
A. Heavy rainfall causing leaching
B. Capillary rise from a saline groundwater table
C. Deposition of volcanic ash
D. Glacial activity
Answer: B
Explanation: In arid/semi-arid regions, high evaporation and saline groundwater cause salts to migrate upward, forming saline soils.

Q60. Which of the following is a major coastal cause of saline soil formation?
A. Overuse of fertilizers
B. Seawater inundation during high tides and storms
C. Forest clearance
D. Wind erosion
Answer: B
Explanation: In coastal belts, especially in deltas, saline soils often form due to seawater flooding and saltwater intrusion into the groundwater

Q61. The Sundarbans delta has marshy soils primarily due to:
A. Saline intrusion and mangrove vegetation decay
B. Sand dune formation
C. Volcanic activity
D. Glacial deposition
Answer: A
Explanation: Marshy soils in Sundarbans form from organic matter from mangroves + tidal saline water intrusion.

Q62. Match the following peaty/marshy soil types with their location:
Soil Type Location
1. Tari soils a. Kerala backwaters
2. Kari soils b. Bihar lowlands
3. Marsh soils c. West Bengal delta
Options:
A. 1–b, 2–a, 3–c
B. 1–a, 2–c, 3–b
C. 1–c, 2–b, 3–a
D. 1–b, 2–c, 3–a
Answer: A

Peaty soil
Q63. Which of the following best describes the colour of peaty soils?
A. Yellowish brown
B. Reddish brown
C. Dark brown to black
D. Greyish white
Answer: C
Explanation: Peaty soils are dark brown to black due to very high organic matter and humus content.

Q64. The texture of peaty soils is generally:
A. Sandy and loose
B. Clayey and sticky
C. Silty with low water retention
D. Gravelly and porous
Answer: B
Explanation: High organic matter and fine particles make peaty soils clayey, sticky, and waterlogged.

Q65. Which of the following is the most abundant nutrient in peaty soils?
A. Nitrogen
B. Organic carbon
C. Potassium
D. Phosphorus
Answer: B
Explanation: Peaty soils have very high organic carbon (often >40%) due to accumulation of undecomposed organic matter.

Q66. Peaty soils are generally deficient in:
A. Organic carbon
B. Humus
C. Phosphorus and potassium
D. Moisture
Answer: C
Explanation: Despite high humus, peaty soils are low in available phosphorus and potassium, which limits crop productivity without fertilization.

Q67. The acidic nature of peaty soils is primarily due to:
A. High calcium carbonate content
B. Accumulation of organic acids
C. High sodium salts
D. Iron oxide leaching
Answer: B
Explanation: Incomplete decomposition in waterlogged conditions produces organic acids, lowering pH.

Q68. Peaty soils in India are generally formed due to:
A. High rainfall, waterlogging, and accumulation of organic matter
B. Deposition of volcanic ash
C. Wind-blown loess deposition
D. Glacial retreat and moraine accumulation
Answer: A
Explanation: Peaty soils develop where heavy rainfall + waterlogging prevent complete decomposition of organic matter, leading to high humus content.

Q69. Which of the following is the chief characteristic of peaty soils?
A. Low organic matter
B. High humus and acidic pH
C. High salinity
D. Sandy texture with high porosity
Answer: B
Explanation: Peaty soils have humus content often above 40%, are dark in colour, and acidic due to incomplete decomposition.

Q70. Which of the following best describes the fertility of peaty soils?
A. Highly fertile for all crops
B. Poor in nutrients like potash and phosphate but rich in organic carbon
C. Sterile and unsuitable for agriculture
D. Fertile only for cereals
Answer: B
Explanation: High organic carbon makes them good for moisture retention, but nutrient deficiencies limit general crop productivity without treatment.

Q71. Which factor is least important in the formation of peaty soils in India?
A. High rainfall
B. Poor drainage
C. Abundant organic matter
D. High wind erosion
Answer: D
Explanation: Wind erosion plays no role; heavy rainfall + waterlogging + organic matter are key.

Forest Soils
Q72. Forest soils in India are mainly found in:
A. Arid and semi-arid regions
B. Snow-bound Himalayan regions and high rainfall areas
C. Coastal plains
D. River deltas
Answer: B
Explanation: Forest soils develop in hilly and mountainous areas with high rainfall and snow, especially Himalayan and Western Ghats regions.

Q73. Which factor plays the most important role in the formation of forest soils?
A. Parent rock alone
B. Vegetation cover and climate
C. Human activity
D. Groundwater movement
Answer: B
Explanation: Forest soils are greatly influenced by dense vegetation and climatic conditions like high rainfall or snowfall.

Q74. The texture of forest soils in hilly regions is generally:
A. loamy and silty
B. Clayey only
C. Gravelly with poor structure
D. Silt loam only
Answer: A
Explanation :forest soil are loamy and silty on valley side and coarse-grained in the upper slope.

Q75. In tropical deciduous forest areas, forest soils tend to be:
A. Very poor in humus
B. Rich in humus and minerals
C. Saline
D. Sterile
Answer: B
Explanation: Moderate climate and vegetation lead to fertile soils rich in humus.

Q76. Which nutrient is often deficient in forest soils of hilly regions?
A. Nitrogen
B. Potassium
C. Phosphorus
D. Organic carbon
Answer: C
Explanation: Leaching often causes phosphorus deficiency in forest soils.

Q77. The most suitable agricultural use of forest soils in lower Himalayan valleys is for:
A. Rice and sugarcane
B. Tea, coffee, spices, and temperate fruits
C. Cotton and millets
D. Wheat and maize only
Answer: B
Explanation: Acidic soils and climate suit tea, coffee, spices, and apple cultivation.

Soil Degradation
Q78. Soil degradation refers to:
A. Only erosion of topsoil
B. Decline in soil fertility, structure, and biological activity
C. Conversion of fertile land into desert only
D. Leaching of nutrients only
Answer: B
Explanation: Soil degradation is a broad term that includes erosion, nutrient depletion, salinisation, acidification, and loss of biological health.

Q79. Which human activity is the largest contributor to soil degradation in India?
A. Deforestation
B. Overgrazing
C. Unscientific agricultural practices
D. Urbanisation
Answer: A
Explanation: Deforestation exposes soil to erosion, leading to rapid degradation, especially in hilly areas.

Q80. Match the following types of soil degradation with their major causes in India:
1. Salinisation –
2. Wind erosion –
3. Gully erosion –
4. Acidification –
a. Over-irrigation
b. Overuse of urea fertilisers
c. Overgrazing in sandy regions
d. River cutting on soft soils
options
A. 1-a, 2-c, 3-d, 4-b
B. 1-d, 2-a, 3-c, 4-b
C. 1-c, 2-a, 3-d, 4-b
D. 1-a, 2-b, 3-d, 4-c
Answer: A
Explanation:
• Salinisation → over-irrigation (Punjab, Haryana)
• Wind erosion → overgrazing in sandy regions (Rajasthan)
• Gully erosion → river cutting in soft soils (Chambal)
• Acidification → overuse of nitrogen fertilisers (tea plantations, NE India)

Q81. Which of the following best defines soil erosion?
A. Natural process of soil formation from parent rock
B. Removal of soil layer by natural agents or human activity
C. Deposition of eroded soil in lowlands
D. Addition of organic matter to soil
Answer: B
Explanation: Soil erosion refers to the detachment and removal of the upper fertile layer of soil by natural agents (water, wind, ice) or human activities.

Question 82
Match the following types of soil erosion with their correct descriptions:
1. Sheet Erosion
2. Rill Erosion
3. Gully Erosion
4. Wind Erosion
A. Removal of a uniform thin layer of topsoil by flowing water
B. Deep and wide channels formed by running water
C. Fine soil particles removed by strong wind, common in arid regions
D. Small channels or narrow cuts formed by water on slopes
Options:
A. 1–A, 2–B, 3–C, 4–D
B. 1–B, 2–D, 3–A, 4–C
C. 1–A, 2–D, 3–B, 4–C
D. 1–C, 2–A, 3–D, 4–B

Answer: C
Explanation:
• Sheet erosion (A) → Uniform thin layer of soil is removed, often unnoticed.
• Rill erosion (D) → Narrow channels form on slopes, easily smoothed by tillage.
• Gully erosion (B) → Larger and deeper cuts that cannot be corrected by normal farming; common in Chambal ravines.
• Wind erosion (C) → Strong winds lift and transport fine particles, especially in dry

Q83. Which type of soil erosion is most common in the Chambal basin?
A. Sheet erosion
B. Rill erosion
C. Gully erosion
D. Wind erosion
Answer: C – Chambal ravines are a classic case of gully erosion due to unchecked runoff.

Q84. Contour bunding is a soil conservation technique in which bunds are constructed:
A. Along the slope gradient
B. Perpendicular to the slope gradient
C. Along the contour lines of the slope
D. Randomly on the field
Answer: C
Explanation: Bunds constructed along contour lines reduce runoff velocity and prevent soil erosion.

Q85. Contour bunding is most effective in:
A. Arid flatlands
B. Mountainous regions with steep slopes
C. Gently sloping lands and undulating terrain
D. Coastal plains
Answer: C
Explanation: Contour bunding is best suited for gentle to moderate slopes, not very steep or flat lands.

Q86. Contour terracing involves:
A. Construction of terraces along the slope gradient
B. Construction of terraces perpendicular to contour lines
C. Construction of terraces along contour lines on slopes
D. Flattening of plains for irrigation
Answer: C
Explanation: Contour terraces are built following contour lines to reduce runoff and soil erosion on slopes.

Q87. Contour terracing is most suitable for:
A. Flat river plains
B. Gentle to steep slopes in hilly regions
C. Coastal wetlands
D. Desert plains
Answer: B
Explanation: Terracing is practiced on slopes to reduce erosion and make the land suitable for cultivation.

Q88. With reference to the Central Arid Zone Research Institute (CAZRI), consider the following statements:
1. CAZRI is located in Bikaner, Rajasthan.
2. It focuses on research related to arid and semi-arid regions of India.
3. CAZRI operates under the Ministry of Environment, Forest and Climate Change.
4. It works on developing drought-resistant crop varieties and soil conservation techniques.
5. CAZRI was established in 1959.
Which of the statements given above are correct?
A. 1, 2, and 3 only
B. 1, 2, 4 and 5 only
C. 2, 3, and 4 only
D. 1, 3, and 4 only
Answer:B. 1, 2, 4 and 5 only
Explanation:
• Statement 1 is correct — CAZRI is located in Bikaner.
• Statement 2 is correct — it focuses on arid and semi-arid region research.
• Statement 3 is incorrect — CAZRI operates under the Ministry of Agriculture & Farmers Welfare through ICAR, not the Ministry of Environment.
• Statement 4 is correct — it works on drought-resistant crops and soil conservation.

Q89. With reference to the Central Soil Conservation Board (CSCB), consider the following statements:
1. CSCB works under the Ministry of Agriculture & Farmers Welfare.
2. Its primary role is to promote soil and water conservation in India.
3. CSCB is responsible for implementing the Integrated Watershed Management Programme (IWMP).
4. It was established after India’s independence in 1947.
Which of the statements given above are correct?
A. 1, 2, and 3 only
B. 1 and 3 only
C. 2, 3, and 4 only
D. All of the above

Answer:A. 1, 2, and 3 only

Explanation:
• Statement 1 is correct — CSCB functions under the Ministry of Agriculture & Farmers Welfare.
• Statement 2 is correct — CSCB promotes soil and water conservation practices across India.
• Statement 3 is correct — CSCB plays a key role in planning and implementing IWMP.
• Statement 4 is incorrect — CSCB was established in 1952, not immediately after independence in 1947.