Trophic Levels and The 10% Rule 1.9&1.10

Conservation of Matter and Energy

matter and energy cannot be created or destroyed; they only can change forms (1st law of thermodynamics)

• food webs demonstrate conservation of energy

2nd Law of Thermodynamics

each time energy is transfered, some is lost as heat

• the amount of useable energy decreases as you move up the food chain

10% rule

in trophic pyramids, only 10% of the energy from one level makes it to the next level; the other 90% is used by the organism and lost as heat

Trophic Levels and 10% Biomass

Producers

produce sun light into chemical energy

Primary Consumers

animals that eat plants

Secondary Consumers

animals that eat primary consumers or herbivores

Tertiary Consumers

animals that eat secondary consumers or carnivores and ominvores

10% biomass

10% rule also applies to biomass (or mass of all living thing at each trophic level)

Calculating Biomass and Energy

J or Kg

• 95,000.00 → 9,500.00