"System of Rice Intensification" of cultivation, in which alternate wetting and drying of rice fields is practised, results in : 1. Reduced seed requirement 2. Reduced methane production 3. Reduced electricity consumption Select the correct answer using the code given below.
- A.1 and 2 only
- B.2 and 3 only
- C.1 and 3 only
- D.1, 2 and 3
Correct answer
Explanation
The correct answer is D, 1, 2 and 3. SRI saves seed, cuts methane and, by using less irrigation water, saves the electricity spent on pumping.
The System of Rice Intensification was developed in Madagascar in the 1980s by the French priest Henri de Laulanié. Young seedlings, 8 to 12 days old, are planted singly and widely spaced, so a farmer needs only about 5 kg of seed per hectare instead of 40 kg or more. The field is kept moist and allowed to dry at intervals rather than flooded, so the soil stays aerated and methane-producing bacteria are suppressed. Because far less water is pumped from wells, diesel and electricity use also falls.
A is wrong because it leaves out the saving in electricity.
B is wrong because it leaves out the large saving in seed.
C is wrong because it leaves out the cut in methane, the main climate benefit of alternate wetting and drying.
Exam tip: SRI = young single seedlings, wide spacing, no continuous flooding: less seed, less water, less methane.
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