Answer:
290,000 cal/m2/yr
Explanation:
The net primary productivity of an ecosystem refers to the amount of energy stored by the biomass of that ecosystem after the energy loss to metabolism and maintenance has been accounted for. Net primary productivity is different from gross primary productivity in that the latter refers to the total energy transferred into the ecosystem before taking the energy loss into account.
Mathematically;
net primary productivity (NPP) = Gross primary productivity (GPP) - Respiration
For the pine forest, NPP = 175,000cal/m2/yr and respiration = 115,000cal/m2/yr , hence;
GPP = 175,000 + 115,000 = 290,000 cal/m2/yr
Therefore, the total amount of energy transfered during photosynthesis for the ecosystem is 290,000 cal/m2/yr.