The gross primary productivity of a meadow in southeastern Iowa is found to be 39,000 kcal/m2. Respiration, which is measured by the amount of CO2 released is 14,500 kcal/m2, what is the net primary productivity for this ecosystem, in kcal/m2 per year? A scientist has measured the gross primary productivity of a forest in northern Idaho to be 26,000 kcal/m2. He also has measured the amount of CO2 given off into the atmosphere as 10,600 kcal/m2. What is the net primary productivity for the forest ecosystem?

The gross primary productivity of a forest ecosystem is measured to be 18 kg C/ m2 -year, the respiration for the system is measured as 7.8 kg C/ m2 –year. What is the NPP of the forest as calculated by measuring the carbon in the biomass?

The net annual primary productivity of a particular wetland ecosystem is found to be 8,000 kcal/m2 per year. If respiration by the aquatic producers is 14,000 kcal/m2 per year, what is the gross annual primary productivity for this ecosystem, in kcal/m2 per year?

If the available biomass for a patch of forest is measured as 12 kg C/ m2 –year, and the amount of CO2 given off into the atmosphere as 7kg C/ m2 –year, what is the GPP?