85 + MCQs on Soil Science (with Answers)

List of 85+ MCQs on soil science ! This will help you to learn about the frequently asked objective type questions on soil science especially compiled for ICAR, ARS, IARI Ph.D and other competitive exams.

1. Hue denotes

(A) Dominant spectrum

(B) Lightness or brightness

(C) Purity

(D) Intensity

Ans. A

2. Phosphorus uptake in alkali soil in the form of _____

(A) H₂PO₄^–

(B) HPO₄^2–

(C) PO₄^3–

(D) H₃PO₄

Ans. C

3. Which fertilizer produce acidity in soil

(A) Ammonium sulfate

(B) Sodium nitrate

(C) Calcium ammonium nitrate

(D) Calcium nitrate

Ans. A

4. Maximum N content found in N fertilizer

(A) Urea

(B) Anhydrous ammonia

(C) Sodium nitrate

(D) Ammonium sulphate

Ans. B

5. Rock phosphate has P₂O₅

(A) 10-20%

(B) 20-40%

(C) 30-50 %

(D) 20-30%

Ans. B

6. The conversion factor for calculating P from P₂O₅

(A) P₂O₅ x 2.29

(B) P x 0.44

(C) P x 2.29

(D) P₂O₅ x 0.44

Ans. D

7. The phenomenon slickenside found in which soil

(A) Inceptisol

(B) Vertisol

(C) Gelisol

(D) Spodosol

Ans. B

8. Which organic fraction not soluble in both acid and alkali

(A) Fulvic

(B) Humic

(C) Humin

(D) All of the above

Ans. C

9. In munsell colour chart hue 10 represents as ______

(A) Red

(B) Black

(C) Grey

(D) Yellow

Ans. D

10. pF scale for Field capacity is _____

(A) 2

(B) 2.5

(C) 3.5

(D) 4.5

Ans. B

11. Available water held between

(A) Saturation to wilting point

(B) Field capacity to hygroscopic coefficient

(C) Only field capacity

(D) Field capacity to wilting point

Ans. D

12. Soil colloidal particle shows the phenomena

(A) Plasticity

(B) Adhesion and cohesion

(C) Flocculation

(D) All of the above

Ans. D

13. The central cation on silica tetrahedron is _____

(A) Al³⁺

(B) Si⁴⁺

(C) Fe²⁺

(D) None of the above

Ans. B

14. Which plant is used for indication of permanent wilting point?

(A) Safflower

(B) Sunflower

(C) Marigold

(D) Both A and C

Ans. B

15. Mica is a type of clay mineral

(A) 1:1

(B) 2:1

(C) 2:1:1

(D) None of the above

Ans. B

16. Hydrogen bond found in which clay mineral

(A) Kaolinite

(B) Montmorillonite

(C) Vermiculite

(D) Beidelite

Ans. A

17. Base saturation in lateritic soil

(A) < 40 %

(B) > 40%

(C) < 20%

(D) > 20%

Ans. B

18. Immobilization of sulphur occur in soil when C:S ratio is _____

(A) < 300:1

(B) > 300:1

(C) > 400:1

(D) > 200:1

Ans. C

19. Denitrification is a process of ______

(A) Oxidation

(B) Reduction

(C) Hydration

(D) Carbonation

Ans. B

20. Microorganism involve in conversion from nitrite to nitrate

(A) Nitrosomonas

(B) Nitrobactor

(C) Pseudomonas

(D) Bacillus

Ans. B

21. Thiourea is type of fertilizer

(A) Slow release

(B) Nitrification inhibitors

(C) Natural nitrification inhibitors

(D) Artificial nitrification inhibitors

Ans. D

22. Chemical formula of thiourea is _____

(A) CO(NH₂)₂

(B) SC(NH₂)₂

(C) HCN

(D) None of the above

Ans. B

23. N content in thiourea is _________

(A) 46%

(B) 36.8%

(C) 22.5%

(D) 33%

Ans. B

24. Quantity of soil to be taken for texture analysis

(A) 10g

(B) 20g

(C) 30g

(D) 40g

Ans. B

25. The K₂O content in Illite varied between

(A) 6 to 10%

(B) 2 to 4%

(C) 10 to 15%

(D) 33%

Ans. A

26. The microorganism lies below < 10°C is called _______

(A) Psychrophiles

(B) Mesophiles

(C) Thermophiles

(D) None of the above

Ans. A

27. Thermophiles organism lies in temperature

(A) > 45°C

(B) > 25°C

(C) < 45°C

(D) < 25°C

Ans. A

28. Optimum temperature for mesophile

(A) 10-20°C

(B) 20-40°C

(C) 40-60°C

(D) 15-20°C

Ans. B

29. Which organism derive their energy from oxidation of complex organic compound

(A) Heterotrophs

(B) Autotrophs

(C) Chemotrophs

(D) Lithotrophs

Ans. A

30. Organism utilize carbon from CO₂ for their cellular synthesis

(A) Hetrotrophs

(B) Chemotrophs

(C) Autotrophs

(D) None of the above

Ans. C

31. Most of the soil organism is _____

(A) Psychrophiles

(B) Mesophiles

(C) Thermophiles

(D) All of the above

Ans. B

32. Optimum growth of bacteria in soil

(A) Acidic

(B) Alkali

(C) Neutral to slightly alkaline

(D) Slightly acidic to neutral

Ans. C

33. Fungi growth optimum in pH

(A) 2.5-4.5

(B) 4.5-6.5

(C) 6.5-7.5

(D) 7.5-8.5

Ans. B

34. Actinomycetes prefer which condition for their growth

(A) Slightly alkaline

(B) Alkali

(C) Acidic

(D) Neutral

Ans. A

35. Aroma of earthy smell in first shower of monsoon is due to _____

(A) Actinomycetes

(B) Bacteria

(C) Fungi

(D) None of the above

Ans. A

36. Which genera of bacteria found maximum in soil?

(A) Azotobacter

(B) Pseudomonas

(C) Bacillus

(D) All of the above

Ans. C

37. Rhizobium is an _____ organism

(A) Hetrotrophs anaerobic

(B) Heterotrophs aerobic

(C) Autotrophs anaerobic

(D) Autotrophs aerobic

Ans. B

38. Which nutrient influence the nodule formation and nitrogen fixation in soil?

(A) pH

(B) N

(C)P

(D) All of the above

Ans. D

39. Nitrification process ceases at pH

(A) < 5

(B) < 6

(C) < 4

(D) < 7

Ans. A

40. Denitrification mostly takes place in _____

(A) Aerobic

(B) Anaerobic

(C) Both

(D) None of the above

Ans. B

41. Nitrification rapid in _____ season

(A) Winter

(B) Rainy

(C) Summer

(D) All of the above

Ans. C

42. The peak microbial population was observed in soil generally after addition of residue

(A) 3-4 week

(B) 2-3 week

(C) 3-4 days

(D) 1-2 week

Ans. D

43. For mineralization of P optimum ratio of C:N:P should be _____

(A) 100:10:1

(B) 50:10:1

(C) 80:10:1

(D) 30:10:1

Ans. A

44. Ammonia volatilization is purely process of _____

(A) Physical

(B) Chemical

(C) Biological

(D) None of the above

Ans. B

45. Which element suppressed Downey mildew of pear millets?

(A) Chloride

(B) Fluoride

(C) Bromide

(D) Lithium

Ans. A

46. Improper development of wheat inflorescence is due to deficiency of _____

(A) Molybdenum

(B) Boron

(C) Calcium

(D) Magnesium

Ans. B

47. Organic matter obtained

(A) OC x 1.724

(B) OC x 2.24

(C) OC x 1.55

(D) OC x 1.64

Ans. A

48. Saturated hydraulic conductivity is measured by _____

(A) Pycnometer

(B) Tensiometer

(C) Amoozemeter

(D) Hydrometer

Ans. C

49. Hydraulic conductivity is found to decrease in the following order

(A) K soil > Ca – soil > Na – soil

(B) Na – soil > K – soil > Ca – soil

(C) Ca – soil < K – soil < Na – soil

(D) Ca – soil > K – soil > Na – soil

Ans. D

50. Which chemical compound is used for improve soil aeration, infiltration and water holding capacity of soil

(A) Jalshakti

(B) Fentachlore

(C) Hydrotech

(D) None of the above

Ans. A

51. Reddish colour in muriate of potash is due to _____

(A) KCl

(B) Colour reagent

(C) Impurities

(D) All of the above

Ans. C

52. Feldspars is primary mineral that occurs pre-dominantly in ________

(A) Igneous rock

(B) Sedimentary rock

(C) Metamorphic rocks

(D) All of the above

Ans. A

53. CO₂ content in rainwater is _______

(A) 0.35%

(B) 0.45%

(C) 0.25%

(D) 0.15%

Ans. B

54. In which point resistant to wind erosion in soil

(A) Permanent wilting point

(B) Hygroscopic point

(C) Field capacity

(D) None of the above

Ans. A

55. Bedrock is absent in which soil?

(A) Black soil

(B) Red soil

(C) Alluvial soil

(D) Forest soil

Ans. C

56. Saline soil also known as _____

(A) Solonchalk

(B) Solonetz

(C) Sodochalk

(D) None of the above

Ans. A

57. Kari is the local name of _____

(A) Acid soil

(B) Saline soil

(C) Acid sulfate soil

(D) Alkali soil

Ans. C

58. The honey-comb structure found in _____

(A) Alluvial soil

(B) Black soil

(C) Saline soil

(D) Laterite soil

Ans. D

59. Which soil occur mainly a soil crust problem?

(A) Sandy soil

(B) Silty clay loam

(C) Loamy soil

(D) Clayey soil

Ans. B

60. Red colour of soil is due to _____

(A) Hematite

(B) Geothite

(C) Glauconite

(D) Maghemite

Ans. A

61. Black colour of soil is due to _____

(A) Titaniferous magnetite

(B) Geothite

(C) Glauconite

(D) Organic matter

Ans. A

62. Total soil order found in world?

(A) 9

(B) 10

(C) 11

(D) 12

Ans. D

63. Flow of nitrogen in soil mainly due to _____

(A) Mass flow

(B) Diffusion

(C) Interception

(D) None of the above

Ans A

64. Micronutrient flow is mainly a _____ process in soil

(A) Mass flow

(B) Diffusion

(C) Interception

(D) None of the above

Ans. B

65. When organic matter added into the soil effect on bulk density

(A) Increased

(B) No effect

(C) Decreased

(D) Both A and C

Ans. C

66. Which factor is more responsible for black colour in kanhar (Vertisol) soil?

(A) Hematite

(B) Titaniferous magnetite

(C) Geotite

(D) Organic matter

Ans. B

67. Which factor is responsible for red colour in bhata (Entisol) soil?

(A) Hematite

(B) Geotite

(C) Maghemite

(D) Gibbsite

Ans. A

68. Yellow colour appear due to hydration of hematite found in which soil?

(A) Bhata (Entisol)

(B) Dorsa (Alfisol)

(C) Matasi (Inceptisol)

(D) Kanhar (Vertisol)

Ans. C

69. Soil order found in Chhattisgarh

(A) 2

(B) 4

(C) 3

(D) 5

Ans. D

70. Which Soil order is newly identified in Chhattisgarh?

(A) Entisol

(B) Mollisol

(C) Inceptisol

(D) Vertisoil

Ans. B

71. Which soil has low water and nutrient holding capacity of Chhattisgarh?

(A) Bhata

(B) Matasi

(C) Dorsa

(D) Kanhar

Ans. A

72. Bhata soil is also known as _____

(A) Clayey

(B) Clay loam

(C) Gravely

(D) Sandy loam

Ans. C

73. Matasi soil is also known as _____

(A) Clayey

(B) Clay loam

(C) Gravely

(D) Sandy loam

Ans. D

74. Dorsa soil is also known as _____

(A) Clayey

(B) Clay loam

(C) Gravely

(D) Sandy loam

Ans. B

75. Kanhar soil is also known as _____

(A) Clayey

(B) Clay loam

(C) Gravely

(D) Sandy loam

Ans. A

76. Which soil covers maximum area in Chhattisgarh?

(A) Bhata

(B) Matasi

(C) Dorsa

(D) Kanhar

Ans. B

77. Bhata soil covers area in Chhattisgarh of total area

(A) 12%

(B) 21%

(C) 39%

(D) 27%

Ans. A

78. Dorsa soil covers area in Chhattisgarh of total area

(A) 12%

(B) 21%

(C) 39%

(D) 27%

Ans. D

79. Kanhar soil covers area in Chhattisgarh of total area

(A) 12%

(B) 21%

(C) 39%

(D) 27%

Ans. B

80. Total soil order found in India

(A) 13

(B) 5

(C) 9

(D) 12

Ans. C

81. Which one is lower category for classification of soil?

(A) Soil order

(B) Family

(C) Soil series

(D) None of the above

Ans. C

82. Which clay mineral is responsible for cracking in black soil?

(A) Kaolinite

(B) Illite

(C) Vermiculite

(D) Montmorillonite

Ans. D

83. pH meter measures

(A) H ions activity

(B) H ions concentration

(C) Al ions

(D) All of the above

Ans. A

84. EC (electrical conductivity) meter measures

(A) Total salt in soil

(B) Soluble salt in soil

(C) Both the salt

(D) None of the above

Ans. B

85. The unit used for the measurement of electrical conductivity is _____

(A) dS/m

(B) uS/cm

(C) mg/m

(D) Both A and B

Ans. D

86. Olsen method is used for phosphorus estimation

(A) Acidic soil

(B) Neutral to alkali soil

(C) Saline soil

(D) All of the above

Ans. B

87. Which method used for determination of available phosphorus in acid soil

(A) Bray

(B) Olsen

(C) Walkley and Black

(D) Jackson

Ans. A

88. KMnO₄ (potassium permanganate) is used for __________

(A) Available nitrogen

(B) Organic carbon

(C) Available phosphorus

(D) Available potassium

Ans. A

89. Which instrument is used for the estimation of potash (K)

(A) Spectrophotometer

(B) Flamephotometer

(C) Colorimeter

(D) Atomic absorption

Ans. B

90. Spectrophotometer is used for determination of _____

(A) N

(B) P

(C) K

(D) All of the above

Ans. B