Question

when considering the carbon cycle, which of the following would most directly affect the number of producers in a land ecosystem?
a the number of land animals dying and returning to the soil
b the number of fish in a large lake
c the amount of fossil fuels produced deep within the earth
d the amount of carbon dioxide in the atmosphere

Explanation:

Producers in a land ecosystem rely on carbon - dioxide for photosynthesis. An increase or decrease in the amount of carbon dioxide in the atmosphere directly affects their ability to produce food. The number of land animals dying and returning to the soil (A) mainly affects soil nutrients and decomposers. The number of fish in a lake (B) is part of an aquatic ecosystem and not directly related to land - based producers. The amount of fossil fuels produced deep within the earth (C) is not a direct factor for producers in a land ecosystem.

Answer:

D. the amount of carbon dioxide in the atmosphere