1. Communities & Biomes
A community is composed of interacting populations of different species.
A biome is a large group of ecosystems that share the same climax community.

2. Limiting Factors
A limiting factor is any biotic or abiotic factor that limits the existence, numbers, reproduction, or distribution of organisms.
Examples: food, predators, water, habitat, temperature

3. Succession
Ecologists refer to the orderly, natural changes and species replacements that take place in the communities of an ecosystem as succession.

4. Primary Succession
The colonization of new sites by communities of organisms is called primary succession.
New sites may be the result of lava flow, an avalanche, dune formation, or a receding glacier.

5. Pioneer Species
The first species of plants to inhabit new land are called pioneer species.
Mosses and lichens are the typical pioneer species.
These plants are responsible for soil formation so other species of plants and animals can inhabit the area.

6. Secondary Succession
Secondary succession refers to the sequence of community changes that occur after a community is disrupted by a natural disaster or human activity. Pioneer species are not necessary since bare soil covers the area.

7. Biomes
Aquatic – located in oceans, rivers, lakes, streams, ponds, or other bodies of water
Terrestrial – located on land

8. Marine Biomes
Photic zone – portion of the biome shallow enough for light to penetrate
Aphotic zone – never receives sunlight
Intertidal zone – portion of the shoreline that lies between the high and low tide line
Estuary – where saltwater and freshwater mix

9. Plankton Live in the photic zone
Composed of mainly protists and marine larvae
Phytoplankton – algae
Zooplankton – animal-like plankton

10. A Review of the Terrestrial Biomes
TUNDRA

11. Taiga or Coniferous Forest

12. Desert

13. Grasslands

14. Temperate Forest

15. Tropical Rainforest