SSC JE Exam - irrigation hydrology rainfall measurement runoff crop water requirements duty delta base period canal types canal lining Question Bank with Options

1. What is the main advantage of a 'perennial canal' over an 'inundation canal'?

A) It requires less maintenance

B) It provides a reliable supply of water throughout the year

C) It has a lower construction cost

D) It causes less seepage

2. Which of the following is a characteristic of 'heavy rainfall' in the context of runoff generation?

A) High infiltration rates

B) Low potential for surface runoff

C) Rapid saturation of soil

D) Low intensity over a long duration

3. The 'rotation period' in irrigation refers to:

A) The duration of a single watering

B) The time between the start of one watering and the start of the next

C) The total time a field is irrigated

D) The time taken for water to reach the field

4. What is the primary environmental concern associated with extensive canal lining, especially with impermeable materials?

A) Increased evaporation

B) Reduced groundwater recharge

C) Increased silt deposition

D) Altered river morphology

5. Which type of rainfall measurement involves estimating rainfall over an area based on readings from a network of gauges?

A) Isohyetal method

B) Average depth method

C) Thiessen polygon method

D) All of the above

6. What is meant by the 'consumptive use' of water by a crop?

A) Total water applied to the field

B) Water lost through evaporation and transpiration

C) Water retained in the soil

D) Water runoff from the field

7. A canal that is designed to irrigate land on both sides of its alignment, with the water level in the canal being higher than the land on both sides, is typically a:

A) Contour canal

B) Side slope canal

C) Ridge canal

D) Inundation canal

8. What is the main purpose of a 'cross regulator' in a canal system?

A) To control the flow into a distributary

B) To increase the water level in the main canal

C) To prevent silt entry into distributaries

D) To regulate water supply to a specific field

9. Which instrument is used to measure soil moisture content?

A) Anemometer

B) Hygrometer

C) Tensiometer

D) Barometer

10. What is the typical range for the Base Period of rice cultivation?

A) 30-60 days

B) 70-150 days

C) 150-200 days

D) 200-300 days

11. The 'irrigation efficiency' refers to the ratio of:

A) Water delivered to the field to water used by the crop

B) Water stored in the root zone to water delivered to the field

C) Water used by the crop to water delivered to the field

D) Water lost to evaporation to water used by the crop

12. What is the primary challenge addressed by canal lining regarding water loss?

A) Evaporation losses

B) Seepage losses

C) Conveyance losses

D) Application losses

13. Which type of canal is designed to carry water from a reservoir or barrage to the main canal?

A) Branch canal

B) Distributary canal

C) Link canal

D) Feeder canal

14. What is the main advantage of using a 'coupler' in a lined canal system?

A) To increase seepage

B) To reinforce the lining at joints

C) To facilitate weed growth

D) To reduce flow velocity

15. If the Delta is 120 cm and the Base Period is 100 days, calculate the Duty.

A) 1000 ha/cumec

B) 1200 ha/cumec

C) 900 ha/cumec

D) 800 ha/cumec

16. What is the primary role of a 'watercourse' in an irrigation system?

A) To carry water from the river to the main canal

B) To distribute water from the distributary to the fields

C) To recharge groundwater

D) To convey water from the main canal to distributaries

17. Which of the following is a type of canal based on its source of supply?

A) Contour canal

B) Ridge canal

C) Perennial canal

D) Side slope canal

18. What is the 'Wilting Point'?

A) The moisture content at which plants can no longer extract water

B) The moisture content at field capacity

C) The moisture content at saturation

D) The optimal moisture content for plant growth

19. The term 'field capacity' in soil physics relates to:

A) The maximum water a soil can hold against gravity after saturation

B) The amount of water available to plants

C) The wilting point of the soil

D) The rate of evaporation from the soil surface

20. Which type of canal serves as a feeder channel to the main canal?

A) Branch canal

B) Distributary canal

C) Watercourse

D) Link canal

21. If a rain gauge records 10 mm of rainfall over a period of 1 hour, what is the intensity of rainfall?

A) 10 mm/hr

B) 1 mm/hr

C) 0.1 mm/hr

D) 100 mm/hr

22. What is the primary objective of using a 'hydraulically designed' canal lining?

A) To increase friction and slow down water flow

B) To improve flow velocity and reduce sedimentation

C) To decrease the wetted perimeter

D) To facilitate weed growth

23. Which of the following is a disadvantage of unlined canals?

A) High initial construction cost

B) Increased seepage and waterlogging

C) Reduced maintenance requirements

D) Limited flow capacity

24. What does the term 'irrigation interval' refer to?

A) The total depth of water applied

B) The time between successive waterings

C) The rate of water application

D) The duration of a single watering

25. A canal that is constructed perpendicular to the contours is known as a:

A) Contour canal

B) Ridge canal

C) Side slope canal

D) Perennial canal

26. Which factor significantly influences the Duty of a canal?

A) The color of the canal water

B) The type of soil and its permeability

C) The time of day the water flows

D) The atmospheric pressure

27. What is the primary function of transpiration in relation to crop water needs?

A) It is a direct loss of water with no benefit to the plant.

B) It is the process by which plants absorb water from the soil.

C) It is the process by which plants release water vapor, aiding nutrient transport.

D) It is the process of water storage within plant tissues.

28. Seepage losses in unlined canals can lead to:

A) Increased groundwater table near the canal

B) Waterlogging of adjacent agricultural land

C) Both A and B

D) Reduced soil fertility

29. What is the purpose of a 'distribution canal'?

A) To carry water from the river to the main canal

B) To distribute water from the main canal to smaller channels

C) To irrigate large tracts of land directly

D) To connect two different river systems

30. Which of the following is a common material used for canal lining?

A) Loose sand

B) Clay

C) Concrete

D) Gravel

31. What is the main advantage of canal lining?

A) To increase seepage losses

B) To reduce the carrying capacity

C) To prevent seepage losses and erosion

D) To increase weed growth

32. A canal that receives water only during floods and is not fed by a perennial source is known as:

A) Perennial canal

B) Inundation canal

C) Distribution canal

D) Link canal

33. Which type of canal is constructed roughly parallel to the contours of the land?

A) Ridge canal

B) Contour canal

C) Side slope canal

D) Main canal

34. A canal that follows the ridge line between two drainage basins is called a:

A) Contour canal

B) Side slope canal

C) Ridge canal

D) Branch canal

35. Which of the following is a type of canal based on its alignment?

A) Perennial canal

B) Inundation canal

C) Ridge canal

D) All of the above

36. What is the unit of Duty?

A) Hectares per cubic meter per second (ha/m³/s)

B) Hectares per cumec (ha/cumec)

C) Cubic meters per second per hectare (m³/s/ha)

D) Meters per day (m/day)

37. A short-term crop with a short base period will generally have a:

A) Higher Delta and lower Duty

B) Lower Delta and higher Duty

C) Higher Delta and higher Duty

D) Lower Delta and lower Duty

38. What is the 'Base Period' of a crop?

A) The period from sowing to harvesting

B) The period from the first watering to the last watering

C) The period from the first watering to the time the crop matures

D) The total duration of the crop's life cycle

39. The relationship between Delta (D), Base Period (B), and Duty (Du) is given by:

A) Du = 8.64 * B / D

B) Du = 8.64 * D / B

C) Du = D * B / 8.64

D) Du = B / (D * 8.64)

40. What is 'Delta' in irrigation hydrology?

A) The time period between successive waterings

B) The total depth of water required by a crop during its entire growth period

C) The rate at which water is supplied to the field

D) The area of land irrigated

41. If the Delta for a crop is 100 cm and the Base Period is 120 days, what is the approximate Duty (in hectares per cumec)?

A) 1500

B) 1200

C) 900

D) 600

42. What is 'Duty' in the context of irrigation?

A) The total area irrigated by a canal

B) The volume of water required to irrigate a unit area of land

C) The area of land that can be irrigated by a unit volume of water flowing continuously

D) The frequency of irrigation for a particular crop

43. Evapotranspiration is the sum of evaporation and transpiration. Which component is usually larger in irrigated agriculture?

A) Evaporation

B) Transpiration

C) Both are equal

D) It varies unpredictably

44. What is meant by 'crop water requirement'?

A) The amount of water needed for germination only

B) The total amount of water lost from the soil and plant surfaces

C) The amount of water lost due to evaporation from soil surface

D) The amount of water required for plant respiration only

45. What is the relationship between rainfall intensity and runoff?

A) Higher intensity rainfall generally leads to lower runoff

B) Runoff is independent of rainfall intensity

C) Higher intensity rainfall generally leads to higher runoff

D) Runoff is inversely proportional to rainfall intensity

46. Which statement best describes runoff?

A) Water that infiltrates into the soil

B) Water that evaporates from the surface

C) Water that flows over the land surface

D) Water stored in underground aquifers

47. What does a tipping bucket rain gauge measure?

A) Wind speed

B) Atmospheric pressure

C) Intensity and duration of rainfall

D) Soil moisture content

48. A standard non-recording rain gauge typically consists of a cylindrical container with a funnel.

A) True

B) False

C) Only in specific regions

D) Depends on the altitude

49. Which of the following is NOT a method of rainfall measurement?

A) Rain gauge

B) Weather radar

C) Anemometer

D) Tipping bucket rain gauge

50. What is the primary purpose of irrigation in agriculture?

A) To increase soil salinity

B) To supplement natural rainfall for crop growth

C) To erode fertile topsoil

D) To promote weed proliferation

irrigation hydrology rainfall measurement runoff crop water requirements duty delta base period canal types canal lining - Question Bank