What are the advantages and disadvantages of replacing the Persian wheel with a tubewell

Advantages: Persian wheel is cheap way of irrigation, it can provide water when needed for crops. Persian wheel is useful in mountainous (hilly) areas due to close water level; it is suitable for small scale farming.

Disadvantages: Persian wheel can irrigate small areas, lot of effort is needed and it is time taking.

Advantages:

(1) Tube well reduces dependence on rain.

(2) Tube well speed can be controlled.

(3) It provides water in large quantity.

(4) Tube well reduces water logging and salinity.

(5) Double cropping in a year is possible.

(6) Increases yield.

(7) Fulfill the need of high yielding varieties.

Disadvantages:

(1) Tube well is costly.

(2) It requires lot of electricity and fuel.

(3) There is shortage of electricity in Pakistan.

(4) Reduces ground water available.

(5) Lack of mechanics for repair.

the correct answer is c.

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