Previous Year Question

Blue carbon is carbon captured from the atmosphere and stored by oceans and coastal ecosystems.

The principal coastal blue-carbon ecosystems are mangroves, seagrass meadows and tidal salt marshes.

These ecosystems absorb carbon dioxide through photosynthesis.

The captured carbon is stored in leaves, stems, roots and below-ground biomass.

A large part of it also accumulates in waterlogged coastal sediments.

Low-oxygen sediment conditions slow the decomposition of organic matter.

Therefore, carbon may remain stored in the sediments of coastal ecosystems for hundreds to thousands of years.

Blue-carbon ecosystems can capture carbon rapidly per unit area and store it for long periods.

The destruction or degradation of these ecosystems can release stored carbon back into the atmosphere.

Therefore, protecting and restoring mangroves, seagrasses and tidal marshes assists in climate-change mitigation.

These ecosystems also help reduce coastal erosion and storm surges.

They provide breeding and feeding grounds for fish, crustaceans, birds and other organisms.

Carbon stored in forest biomass and agricultural soils is terrestrial carbon, not blue carbon. Therefore, option (b) is not correct.

Carbon in petroleum and natural gas is fossil carbon, whereas carbon present in the atmosphere is not itself called blue carbon. Therefore, options (c) and (d) are not correct.