A graduate student has told you that the average net primary productivity (NPP)per area is greater on land than in oceans despite the fact that their total NPP potential is the same.What is one possible reason for this difference?
A) Terrestrial systems always have the highest NPP because terrestrial animals need to consume more biomass than oceanic organisms
B) She is not correct. Oceans will always have the highest NPP because there is such an abundance of phyto- and zoo- plankton
C) Per area, land will have an average NPP greater than oceans because oceans cover much more of Earths total area
D) The NPP per area is equal between land and ocean

Question

Quizplus · Accepted Answer

Land has a much smaller surface area compared to oceans, meaning that the same total NPP potential is spread over a smaller area on land. Therefore, the average NPP per area will be greater on land than in oceans. This is not due to the fact that terrestrial animals consume more biomass than oceanic organisms or that oceans do not have an abundance of phyto- and zoo-plankton. The statement that oceans always have the highest NPP is also incorrect as NPP per area is not the same as total NPP.

A Graduate Student Has Told You That the Average Net