5. Recently, some areas in the United States have seen an increase in trees due to reforestation efforts. How
might the carbon cycle be altered after a large-scale
reforestation effort? Select all correct answers.
a. Atmospheric carbon dioxide levels would
decrease because the new trees would absorb
carbon dioxide during photosynthesis.
b. Atmospheric carbon dioxide levels would stay
the same because the new trees would absorb
as much carbon dioxide as they produce.
c. Atmospheric carbon dioxide levels would
decrease as trees grew larger and more
carbon was stored in wood.
d. Atmospheric carbon dioxide levels would
increase as new trees allowed ecosystems to
support an equal number of new animals.