What is the most likely effect a decrease of plant life in the biosphere would have on the atmosphere? a. a decrease in plant life would have no effect on the atmosphere. b. a decrease in plant life would cause carbon dioxide levels to increase and oxygen levels to decrease. c. a decrease in plant life would cause carbon dioxide levels to decrease and oxygen levels to increase. d. a decrease in plant life would cause an increase in all gases in the atmosphere.

Why are carbon dioxide concentrations expected to increase? a carbon dioxide concentrations are expected to increase, because fossil fuel burning is expected to increase b. carbon dioxide concentrations are expected to increase, because of an increase in agriculture. c.carbon dioxide concentrations are expected to increase, because more land will have to be cleared for increasing populations and agricultural use. d. all of the above select the best answer from the choices provided mark this and return save and exit next submit submit