MPPSC 2023 Prelims Paper-I · Question 10 of 100

Correct — B or C (both accepted). 'Green Muffler' is the term used, especially by Indian highway authorities, for a dense belt of trees and shrubs planted along a road, highway or around an industrial unit specifically to abate noise: the vegetation absorbs and scatters traffic or industrial sound waves, cutting the noise reaching nearby areas — the primary, defining purpose of the term. The same plantation belt also intercepts dust and vehicular particulate matter, giving it a secondary role in curbing air pollution, which is likely why the commission granted grace and accepted both (b) Air and (c) Noise.

• (a)Soil — Tree belts can help check soil erosion incidentally, but that is not what the term 'Green Muffler' specifically refers to — its defining purpose is noise (and secondarily air) mitigation, not soil pollution.
• (d)Water — A roadside/industrial tree belt has no established role in mitigating water pollution — unrelated to the Green Muffler concept.

'Green Muffler' refers to a purpose-planted belt of trees and shrubs along highways, roads or around industrial areas, used as a natural, low-cost alternative to concrete noise barriers. The dense vegetation absorbs and scatters sound waves from traffic or machinery, reducing the noise that reaches nearby residential or sensitive areas. As a secondary co-benefit, the same belt also traps dust and particulate matter from vehicle exhaust, contributing to air-quality improvement.

The trap is treating 'Green Muffler' as a general afforestation or air-pollution term and missing its primary, defining purpose — noise abatement — which is where the name itself comes from (a 'muffler' dampens sound).

• 'Green Muffler' is a dense plantation belt of trees and shrubs along highways or industrial areas
• Its primary purpose is to absorb and scatter sound waves, reducing noise pollution
• It has a secondary co-benefit of trapping dust/particulate matter, aiding air quality
• It functions as a natural, low-cost alternative to concrete noise barriers along highways

• Treating 'Green Muffler' as purely an air-pollution term and missing its primary noise-control purpose
• Confusing 'Green Muffler' with general afforestation or a green belt used only for soil/water conservation

MPPSC/UPSC environment sections test terminology like 'Green Muffler', 'green belt' and 'buffer zone' — expect direct definition-matching questions on what each measure targets.

No directly related past PYQ was found.

• practice — not a real PYQ

  The primary purpose of planting a 'Green Muffler' belt of trees along a highway is to control:

  • (a)Soil erosion
  • (b)Water pollution
  • (c)Noise pollution
  • (d)Light pollution

  Answer(c) Noise pollution — the vegetation belt absorbs and scatters traffic noise reaching nearby areas.

• practice — not a real PYQ

  Besides reducing noise, a roadside 'Green Muffler' plantation also provides which secondary environmental benefit?

  • (a)Groundwater recharge
  • (b)Trapping dust and particulate matter, aiding air quality
  • (c)Preventing floods
  • (d)Reducing soil salinity

  Answer(b) Trapping dust and particulate matter, aiding air quality — a secondary co-benefit of the same vegetation belt.