Question

Duty of water of canal system does not depends on

• A. Area of land irrigated
• B. Method of cultivation
• C. Type of the crop
• D. Base period of the crop

Hint:

Duty of water is a measure of efficiency, expressed as Hectares/cumec.
Think of it like the "mileage" of water. Better mileage (higher duty) depends on the car (crop type), driving conditions (climate, soil), and driver skill (cultivation method).
The total distance traveled (area irrigated) is a result, not a cause, of the mileage.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
The question asks which of the given factors does not influence the "Duty of water".

Step 2: Detailed Explanation:

Duty of water (D) is a term in irrigation engineering that defines the efficiency of water use. It is the area of land, in hectares, that can be irrigated by a unit discharge of water (1 cubic meter per second, or cumec) flowing continuously for the entire base period of the crop.
\[ D = \frac{\text{Area (hectares)}}{\text{Discharge (cumecs)}} \] The factors that affect the duty of water are:

• (C) Type of the crop: Different crops have different water requirements. A water-intensive crop like rice will have a lower duty (irrigates less area per cumec) than a crop like wheat.

• (D) Base period of the crop: The base period is the duration for which irrigation is supplied. A longer base period for the same total water depth means the required flow rate is lower, which results in a higher duty.

• (B) Method of cultivation: Efficient cultivation and irrigation methods (like furrow or drip irrigation versus inefficient flooding) reduce water losses, meaning the same amount of water can irrigate a larger area, thus increasing the duty.

• Other factors include climate, soil type, and canal conditions (lining reduces seepage losses, increasing duty).



(A) Area of land irrigated is the result of the duty, not a factor that determines it. The duty is a property of the system (crop, soil, climate, efficiency) that tells you how much area you can irrigate with a certain flow. It is an intensive property, not an extensive one.

Step 3: Final Answer:
The duty of water does not depend on the total area of land irrigated; rather, it helps to determine it.