Why is net primary production (NPP)a more useful measurement to an ecosystem ecologist than gross primary production (GPP)? A)NPP can be expressed in energy per unit of area per unit of time [J/(m².yr]. B)NPP is expressed in terms of carbon fixed by photosynthesis for an ecosystem. C)NPP represents the stored energy available to consumers in an ecosystem. D)NPP is the same as the total biomass of the photosynthetic autotrophs present. E)NPP shows the rate at which the total biomass is utilized by primary consumers.

Question

Quizplus · Accepted Answer

NPP represents the amount of energy available to consumers after autotrophs have performed respiration and maintenance, so it is a more useful measurement for understanding the amount of energy that can be passed on to higher trophic levels. GPP only represents the total amount of carbon fixed by photosynthesis, without taking into account any energy used by the autotrophs themselves. NPP can be expressed in energy per unit of area per unit of time and is not directly equivalent to total biomass or the rate of biomass utilization.

Why Is Net Primary Production (NPP)a More Useful Measurement to an Ecosystem