The total depth of water over irrigated land required by a crop grown on it during the entire base period of the crop is known as
- ADelta of irrigationCorrect
- BDuty
- CCapacity factor
- DNone of these
Solution
Concept
Delta of Irrigation
Formula
Δ = (8.64 × B) / D
Step-by-step solution
1. Identify the required term: The total depth of water required by a crop during its entire base period. 2. Recall the definition: Delta (Δ) represents the total depth of water needed by a crop, related to Base period (B) and Duty (D) by Δ = (8.64 × B) / D. 3. Select option A (Delta of irrigation).
Explanation
Delta refers to the total depth of water required by a crop from the time of its planting until harvesting to fully grow and mature.
Shortcut
To easily remember the difference between key irrigation terms: - Delta (Δ) = Depth: "Delta" starts with D and stands for total Depth of water (measured in cm or meters). -Duty = Duty of 1 cumec: It represents the area (duty) of land 1 cumec of water can irrigate. - Base Period = Time: The number of days (base duration) between the first and last watering.
Common mistake
Students often confuse Delta with Duty, selecting Option B (Duty) which represents the area of land irrigated per unit discharge, rather than Option A (Δ) which represents the total depth of water required.
Correct answer: A) Delta of irrigation