Primary Productivity, Trophic Levels, Energy Flow, 10% rule

What has a high net primary productivity?

Freshwater wetlands, tropical forests, coral reefs, and algal beds each have a high

primary productivity

the rate at which biomass is produced by autotrophs

Secondary Productivity

the rate at which consumers convert the chemical energy in food to their biomass

Energy flow

flows in one direction through ecosystems.

photosynthesis (inputs)

6CO2 + 6H2O (energy of sunlight) ------🡪

photosynthesis (outputs)

C6H12O6 (glucose) + 6O2

photosynthesis

the process by which plants convert the energy of sunlight into sugar

cellular respiration

The process of releasing energy from glucose and other carbohydrates

surplus glucose

passed to herbivores and other consumers through food webs.

Gross primary productivity (GPP)

The total amount of solar energy captured by producers during the process of photosynthesis over time

Net Primary Productivity (NPP)

the amount of energy lost through cellular respiration  (R) by producers subtracted from the gross primary productivity of an ecosystem.

How to calculate productivity

• Photosynthesis (producers) – Cellular Resp. (Producers) = Net Primary Productivity

• or

• GROSS PRIMARY PRODUCTIVITY – CELLULAR RESPIRATION (PROD)= NET PRIMARY PRODUCTIVITY

Primary Productivity includes

plants, algae, and photosynthetic bacteria

Secondary Productivity includes

primary consumers/ heterotrophs, herbivores, and carnivores