Refer to the graph. The FACE experiment conducted in a North Carolina pine forest analyzed the effects of two factors on forest NPP.These two factors were A) low and high levels of CO₂. B) low and high levels of nitrogen fertilization. C) levels of CO₂ and nitrogen fertilization. D) levels of CO₂ and atmospheric temperature. E) levels of nitrogen and atmospheric temperature.

Question

Quizplus · Accepted Answer

The graph shows the effects of two factors on forest NPP, which are the levels of CO₂ and nitrogen fertilization. The x-axis represents the levels of CO₂ and nitrogen fertilization, while the y-axis represents the forest NPP. Therefore, the correct answer is C, which states that the two factors analyzed in the FACE experiment were the levels of CO₂ and nitrogen fertilization.

Refer to the Graph