Class 12 Botany simulations · Ecosystem

Gross and net primary productivity

Plants fix energy by photosynthesis (GPP) and use some of it in respiration. What remains (NPP) is food for consumers.

Open the simulation

What to notice

Although oceans cover about 70% of the surface, their productivity is only about 55 billion tons of the biosphere’s 170.

Key relation

NPP = GPP − R

Try this

Increase respiration losses. How much is left for herbivores?

What you can change

• Gross primary productivity: 500 to 5000 g/m²/yr
• Respiration losses: 20 to 80 %

More in Ecosystem

• Decomposition of detritus
• Pyramid of energy (10 per cent law)

See all Class 12 Botany simulations or every Physica simulation.