Scientists calculated the net primary productivity (NPP) at two different forest sites, which have the same gross primary productivity (GPP). Forest A has an NPP of 1,650 kcal/m^2/year, while Forest B has an NPP of 1,110 kcal/m^2/year. Which of the following statements is best supported by the data? a. Forest A has a higher rate of bacterial decomposition than Forest B. b. Forest A has greater biodiversity than Forest B. c. Producers in Forest A have lower rates of cellular respiration than those in Forest B. d. Producers in Forest A have more biomass than those in Forest B.

The best-supported statement by the data provided is c. Producers in Forest A have lower rates of cellular respiration than those in Forest B.

• Gross Primary Productivity (GPP) is the total amount of energy that plants capture and store during photosynthesis. Net Primary Productivity (NPP) is the amount of energy that is left after subtracting the energy used by plants for their own cellular respiration (R). The formula to calculate NPP is:
• NPP = GPP - R
• Given that both Forest A and Forest B have the same GPP, but Forest A has a higher NPP of 1,650 kcal/m^2/year compared to Forest B, which has an NPP of 1,110 kcal/m^2/year, this indicates that Forest A must be using less energy for cellular respiration than Forest B because there is more leftover energy (i.e., a higher NPP). Therefore, the difference in NPP can be attributed to the variance in energy expenditure through respiration by the producers (plants) in each forest.