Subtraction of which of the following will convert gross primary productivity into net primary productivity?
A) the energy contained in the standing crop
B) the energy used by heterotrophs in respiration
C) the energy used by autotrophs in respiration
D) the energy fixed by photosynthesis
E) all solar energy

Question

Quizplus · Accepted Answer

Gross primary productivity (GPP) is the total amount of organic matter produced by plants through photosynthesis. Net primary productivity (NPP) is the amount of organic matter remaining after plants have used some of the energy through respiration. Therefore, to convert GPP into NPP, we need to subtract the amount of energy used by autotrophs in respiration, which is option C. Options A, B, D, and E do not relate directly to the conversion from GPP to NPP.

Subtraction of Which of the Following Will Convert Gross Primary