Slide 1
Energy in Ecosystems
Food Chains, Food Webs and Energy Pyramids
Slide 2
Photosynthetic organisms
Capture energy from sunlight, CO2 and H2O
Most producers are photosynthetic
Chemosynthetic organisms
Capture energy from chemical compounds in the surroundings
Slide 3
Herbivores
Eat only plants and fungi
Omnivores
Eat both plants/fungi and animals
Carnivores
Eat only animals
Detrivores
Eat dead organic matter
Decomposers
Break down organic matter into simpler compounds
Slide 4
Trophic Structures
Manner in which energy moves through an ecosystem
Each ecosystem has its own unique trophic structure
Slide 5
Producers
Autotrophs (Photosynthesizers, Chemosynthetic organisms)
Primary consumers
Herbivores and omnivores that eat producers
Secondary consumers
Carnivores and omnivores that eat herbivores
Tertiary consumers
Carnivore eats another carnivore
Decomposers and Detrivores
Consume decaying producers and consumers
Slide 6
Energy is lost in each step up a food chain
Only 10 percent of the energy from one level on the food chain is available to the next level
Slide 7
Many consumers and decomposers have more than one food source
Movement of energy occurs in complex webs rather than in simple chains
Slide 8
Arctic Marine Food Web
Slide 9
A Simplified Food Web?
Slide 10
Slide 11
Energy pyramids show the reduction of available energy at each higher trophic level
Slide 12
Slide 13