Which statement below best summarizes the likely effects on the carbon cycle of clear-cutting,
or removing all of the trees, in vast areas in a
forest?
A. Clear-cutting would reduce the amount of
carbon dioxide found in the atmosphere.
B. Clear-cutting would limit the amount of nitrogenfixing
bacteria in the area.
C. Clear-cutting would allow for secondary
succession of smaller plants and more carbon.
D. Clear-cutting would increase the amount of
carbon dioxide found in the atmosphere.

D. Clear-cutting would increase the amount of carbon dioxide found in the atmosphere

Explanation:

Plants including trees are organisms that help maintain the balance of carbon in the carbon cycle. They do this via the process of PHOTOSYNTHESIS, which is the way they obtain their energy and carbon source. During photosynthesis, trees (plants) absorb carbon in form of atmospheric carbon dioxide (CO2) from the air through the STOMATA on their leaves.

CO2 is an input substance in order for photosynthesis to occur. In a case where all the trees (plants) of a forest has been clear cut or removed, there will be no organisms to directly absorb the carbon dioxide (CO2) released into the atmosphere via respiration. Hence, the amount of carbon dioxide found in the atmosphere would increase.

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