WARM UP
What are the 4 levels of organization
in Ecology?
ECOSYSTEMS:
Energy Flow
Food Chains
www.swpc.noaa.gov/
Autotrophs
• Means “self-feeder”
• Organisms that obtain their energy from sunlight or
chemical reactions
• Two different processes to gain energy:
– Photosynthesis
– Chemosynthesis
Phytoplankton bloom
off Irish Coast
http://www.galway.net/galwayguide/pod/phytoplankton.small.jpg
Photosynthesis
• Chemical reaction that transforms light energy into
chemical energy.
• Creates carbohydrates: sugars and starches.
• Carbon Dioxide + Water → Glucose + Oxygen
http://www.physicalgeography.net/fundamentals/images/photosynthesis.jpg
Chemosynthesis
• Chemical reaction that transforms one type of chemical
energy into a usable chemical energy.
• Many derive energy from sulfur-containing molecules.
– Bacteria in hydro-thermal vent communities.
• Unique because they
do not derive energy
from the sun.
http://aich.aiistudentwork.com/students/joshpierce/blog/wp-content/uploads/2008/01/hydrothermal_vent.jpg
Hydrothermal Vents
https://www.youtube.com/watch?v=BXGF3XS-yAI
Primary Production
• Autotrophic organisms are the base of all energy in
ecosystems.
• Called primary production:
– Amount of chemical energy converted from solar energy
through the process of photosynthesis
– Measured by determining biomass
• Biological mass = total dry weight of plant
matter
Heterotrophs
• Means “other feeder”
• Organisms obtain their energy from the
consumption of other organisms
Heterotroph Diversity
Images from Google Image Search
Primary Consumers
– Heterotrophic organisms consume
producers
– Consume plants or algae
– Known as herbivores or plant eaters
– Come in all shapes and sizes
Images from Google Image Search
Secondary Consumers
• Carnivores- meat eaters
• Omnivores— eat both producers and
consumers
(Humans, bears and dogs)
• Detritivores (decomposers)
– Eat dead organisms
– Very important to ecosystem
Images from Google Image Search
)
The Energy Pyramid
• Movement of energy through an ecosystem
– Illustrated by the energy pyramid
• Visual way energy moves through food chain
• Each step called a trophic (feeding) level
Biomass Pyramid
Trophic Level
4th
Carnivore
3rd
Carnivore
2nd
Herbivores
1st
Producers
The Energy Pyramid
• First trophic level
– Base of pyramid formed by producers
• Second trophic level
– Primary consumers who eat producers
• Third trophic level
– Secondary consumers who eat primary consumers
• Fourth trophic level
– Tertiary consumers who eat secondary consumers
Images from Google Image Search
Energy Loss
• Only about 10% of the energy available in an ecosystem is
transferred from one trophic level to the next.
• The rest of the energy is lost through heat and waste products
(including nails, hair, horns, hooves, etc.)
http://mrskingsbioweb.com/images/enpyr1.gif