Question

A forest has a GPP of 20,000 kcal/m²/year, and 40% of this energy is used for respiration. Calculate the amount of energy available as NPP.

Answer 1

GPP (Gross Primary Productivity) = 20,000 kcal/m²/year

Respiration loss = 40% of 20,000

= `40/100 × 20,000`

= 8,000 kcal/m²/year

Net Primary Productivity (NPP)

= GPP − Respiration

= 20,000 − 8,000

= 12,000 kcal/m²/year