E c o l o g y Energy Pyramids Walnut High School P r e s e n t s

EQ: What is the rule of 10% and how does that affect the amount of food the next energy level must consume?

The Laws of Thermodynamics and FOOD CHAINS !

The 10 % RULE !

The maximum amount of ENERGY that passes from one trophic level to the next is 10%. 90% of the ENERGY at each trophic level is used to keep the organisms alive and is converted to HEAT.

Always start with the SUN.

PHYTOPLANKTON The 10% RULE ! 90% of the ENERGY captured by PRODUCERS is used to keep themselves alive (converted to heat). Max. 10 % to HERBIVORES HEAT

PRODUCERS HERBIVORES 1st Order CARNIVORES 2nd Order CARNIVORES 3rd Order CARNIVORES Producers are the BASE of the pyramid of biomass because their ENERGY comes direct SUN from the SUN.

ZOOPLANKTON PHYTOPLANKTON The 10% RULE ! 10% HEAT Max. 10 % to CARNIVORES 90% 90% was used to keep the HERBIVORES alive.

PRODUCERS HERBIVORES 1st Order CARNIVORES 2nd Order CARNIVORES 3rd Order CARNIVORES HERBIVORES exist on only 10% of the ENERGY from PRODUCERS.

ZOOPLANKTON PHYTOPLANKTON 1st Order CARNIVORES The 10% RULE ! 90% HEAT Max. 10 % to 2nd O. CARNIVORES 10%

PRODUCERS HERBIVORES 1st Order CARNIVORES 2nd Order CARNIVORES 3rd Order CARNIVORES 1st O. Carnivores are max.10% of HERBIVORES.

ZOOPLANKTON PHYTOPLANKTON 1st Order CARNIVORES 2nd Order CARNIVORES The 10% RULE ! 10%

PRODUCERS HERBIVORES 1st Order CARNIVORES 2nd Order CARNIVORES 3rd Order CARNIVORES There isn’t much ENERGY left near the top.

PRODUCERS HERBIVORES 1st Order CARNIVORES 2nd Order CARNIVORES 3rd Order CARNIVORES The 10% RULE......results in this ECOLOGICAL PYRAMID

PRODUCERS HERBIVORES st Order CARNIVORES nd Order CARNIVORES - 1 3rd Order CARNIVORES 0.1 The 10% RULE......is used to help predict NUMBERS.

The 10% RULE......is used to help predict BIOMASS.

The ecological pyramid at ZUMA. ZOOPLANKTON PHYTOPLANKTON 2nd Order CARNIVORES 1st Order CARNIVORES 10%

Population size ratios at ZUMA. 10% 1, individuals individuals individuals individual

For every 1 lb. of halibut, how many lbs. of sea lion can be supported ? ? 1 lb.

For every 1 lb. of halibut, 0.1 lbs. of sea lion can be supported ! 0.1 lbs 1 lb.

ZOOPLANKTON PHYTOPLANKTON 1st Order CARNIVORES 2nd Order CARNIVORES For a 30 lb. halibut, 30,000 lbs. of phytoplankton are necessary ! 30 lbs. 300 lbs. 3,000 lbs. 30,000 lbs.

REVIEW QUESTIONS: 1. What is the 10% rule ? 2. Where does most of the ENERGY go at each trophic level ?