First go through the text (given after the questions) and then attempt the questions.

QUES 1 . Carbon-storing natural features that exchanges carbon with other reservoirs is known as-

a . Carbon sink

b . Carbon reservoir

c . Carbon source

d . Carbon capture

Answer – b

QUES 2 . Which among the following can be regarded as examples of carbon sinks-

1 . Artificial trees.

2 . Capturing and storing CO2 by injection into the ocean floor.

3 . Replicating the natural process of mineral carbonation.

Select the correct answer using the code given below.

a . 1 & 3

b . 2 only

c . 2 & 3

d . 1 , 2 & 3 

Answer – d


Carbon sinks are natural systems that suck up and store carbon dioxide from the atmosphere.

A carbon sink is a natural or artificial reservoir that accumulates and stores some carbon-containing chemical compound for an indefinite period. The process by which carbon sinks remove carbon dioxide (CO2) from the atmosphere is known as carbon sequestration.

Types of carbon sink

Carbon sinks can be grouped into natural sinks and artificial sinks.

A . Natural sinks: 

It includes-

1 . Absorption of carbon dioxide by the oceans via physicochemical and biological processes.

2 . Photosynthesis by terrestrial plants.

B . Artificial sinks:

1 . Artificial trees- In 2012, scientists from Columbia University came up with a technique to develop ‘artificial trees’ that passively soaks up carbon dioxide from the air using “leaves” that are 1,000 times more efficient than true leaves that use photosynthesis.

2 . Capturing and storing CO2 by injection into the ocean floor or underground empty rock formations that used to hold fossil fuels

3 . Replicating the natural process of mineral carbonation that uses CO2 to transform natural minerals into carbonate rocks like limestone.

Though the creation of artificial sinks has been discussed, no major artificial systems remove carbon from the atmosphere on a material scale.

Paris Agreement carbon sink target 

India has committed a target of creating an additional carbon sink the equivalent of 2.5 billion to 3 billion tonnes carbon dioxide by 2030.

Carbon sources 

Processes which add extra carbon to the atmosphere are known as carbon sources.For example-

1 . Combustion of fossil fuels (coal, natural gas and oil) by humans for energy and transportation
2 . Farmland (by animal respiration)

Carbon reservoir

Carbon-storing natural feature (such as a forest or the land mass) that exchanges carbon with other reservoirs.

Difference between Carbon Sink and Carbon Reservoir

1 . A reservoir from which no outflow of carbon compounds takes place is called carbon sink whereas  carbon reservoirs exchanges carbon with other reservoirs.

2 . Also a carbon sink accumulates carbon, whereas a carbon reservoir has accumulated carbon.

3 . A carbon sink is an ongoing process which is increasing the amount of carbon stored in it. Whereas although a carbon reservoir might exchange individual carbon-based molecules with other parts of the carbon cycle, as much will go out as goes in, keeping the amount of carbon in the reservoir broadly constant.