UPSC Prelims 2021 GS Paper I · Q19 of 98 Environment & Ecology easy

What is blue carbon?

  1. (a) Carbon captured by oceans and coastal ecosystems ✓ UPSC's answer
  2. (b) Carbon sequestered in forest biomass and agricultural soils
  3. (c) Carbon contained in petroleum and natural gas
  4. (d) Carbon present in atmosphere

Why the answer is (a)

• Blue carbon is the carbon captured and stored by ocean and coastal ecosystems — mangroves, salt marshes and seagrass meadows — in their biomass and, especially, their sediments (option a).

• These habitats store carbon per unit area several times faster than terrestrial forests and hold it for millennia if undisturbed.

• Carbon in forests and soils (b) is 'green carbon'; fossil-fuel carbon (c) and atmospheric CO2 (d) are not blue carbon.

• India's mangroves (Sundarbans, Bhitarkanika) are its main blue-carbon stock; MISHTI is the national mangrove initiative.

• Hence option (a).

Why the other options are wrong

(b) Carbon sequestered in forest biomass and agricultural soils
Forest and soil carbon is green carbon, not blue.
(c) Carbon contained in petroleum and natural gas
Fossil-fuel carbon is not blue carbon.
(d) Carbon present in atmosphere
Atmospheric carbon is not blue carbon.

Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2021, held on 10 October 2021. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.

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