Crops, Watering and Waterlogging

JKSSB Junior Engineer (Civil) · Irrigation Engineering · 14 practice questions with answers and explanations: 9 Easy, 5 Medium, 0 Hard.

Sample questions

Sample Easy question 1

Waterlogging of irrigated land is caused mainly by:

  1. A rise of the water table to the root zone
  2. Heavy rain in winter
  3. A fall of the water table
  4. Excess use of fertiliser
Show answer

Answer: A. Seepage from canals and over-irrigation raise the water table.

Sample Easy question 2

The permanent wilting point is the moisture content at which:

  1. The soil is saturated
  2. The plant grows fastest
  3. The soil is at field capacity
  4. Plants can no longer extract water from the soil
Show answer

Answer: D. It marks the lower limit of the water available to plants.

Sample Easy question 3

Which of these is a remedy for waterlogging?

  1. Lining the canals and providing drainage
  2. Irrigating more often
  3. Increasing the canal discharge
  4. Raising the water table
Show answer

Answer: A. Reducing seepage and lowering the water table keeps the root zone free of excess water.

Sample Medium question 4

The consumptive use of a crop is 500 mm and the effective rainfall is 150 mm. The net irrigation requirement is:

  1. 500 mm
  2. 350 mm
  3. 650 mm
  4. 150 mm
Show answer

Answer: B. Net irrigation requirement = consumptive use − effective rainfall.

Sample Medium question 5

Of 100 units of water diverted, 80 units reach the field. The conveyance efficiency is:

  1. 125%
  2. 80%
  3. 100%
  4. 20%
Show answer

Answer: B. Conveyance efficiency = water delivered ÷ water diverted.

Sample Medium question 6

A canal with a conveyance efficiency of 80% feeds fields with an application efficiency of 60%. The overall efficiency is:

  1. 70%
  2. 48%
  3. 140%
  4. 20%
Show answer

Answer: B. 0.8 × 0.6 = 0.48.

More Irrigation Engineering topics for JKSSB Junior Engineer (Civil)