1. Characteristics of Ecosystems

2. Succession Succession—plant regrowth after a catastrophe
Primary and secondary
Primary—development in an area previously uninhabited
First animals in the area are called pioneer species
Exposed rock
Lichen are the first plant to grow

3. Primary Succession Begins where there is no soil
Sides of volcanoes
Landslides
flooding
Lichens, who need no soil, grow on rocks
Then mosses grow on new soil
Pioneer species
Simple plants die, creating more nutrients for soil
Grass, wildflowers and other plants take over

5. Secondary Succession
Reestablishment of a damaged ecosystem where soil was left intact
No end, any damages causes it to go over and over again

6. Secondary Succession
Begins where soil is already present and organisms once lived
Occurs faster than primary
Forest fires, tornadoes

8. Climax Community
Stable group of plants and animals that is the end result of succession process
Does not always mean big trees
Grasses in prairies
Cacti in deserts

9. Energy Flow Begins with the sun as photosynthesis
It flows through ecosystems from producers to consumers.
Producers make food
Consumers use food by eating producers or other consumers

10. Autotrophs Any organism that can produce its own food supply
A.k.a. producer
Plants, algae, some protists and bacteria
Can also be:
Photoautotrophs
Using light energy
Chemoautotrophs
Using chemical energy from hydrothermal vents on the ocean floor or gets it from inside the guts of other animals

11. Tube Worms living in Black Smoker
copyright cmassengale

12. Feeding Relationships

13. Food Chains
Energy flows through an ecosystem in one direction from producers to various levels of consumers

14. Feeding Relationships
Food Chain
Simple energy path through an ecosystem
Food Web
More realistic path through an ecosystem made of many food chains

15. Food Chain

16. Food Web

17. Trophic Levels
Each level in a food chain or web is called a trophic level
Producers
Always the first level
How the energy enters
Herbivores
second trophic level
Primary consumers
Carnivores/Omnivores
Remaining trophic levels
Secondary and tertiary consumers

18. Ecological Pyramids
Graphic representation of the relative amounts of energy or matter at each trophic level
Energy pyramid
Biomass pyramid
Pyramid of numbers

19. Energy Pyramid

20. Biomass
The amount of organic matter comprising a group of organisms in a habitat
As you move up a food chain, both available energy and biomass decrease
Energy transfers up, but diminishes with each transfer

21. Biomass Pyramid

22. Pyramid of Numbers