5c

Question 1

Define GPP Gross primary productivity

Answer 1

In plants the rate at which light from the sun catalyse the production of new plant material

Measured in gm-2 year-1

gCm-2year-1
kJm-2year-1

Question 2

Define net primary productivity (NPP)

Answer 2

The material produced by photosynthesis and stored as new plant body tissue that is

NPP = GPP - R

Rate at which energy is stored in plant biomass