Concepts 21.1-21.3 Flashcards
What is an ecosystem?
Sum of all the interactions between biotic and abiotic factors in environment
What are the two major types of biomes?
Terrestrial and aquatic
What are the 4 main ecological roles?
- Primary producers
- Primary consumers
- Secondary consumers
- Tertiary consumers
What is a food chain?
A sequence of organisms eating one another, along which energy flows in an ecosystem.
Portion of a food web
What is a food web?
A group of organisms in an ecosystem with trophic or energetic connections
What is bottom-up limitation?
Ecosystems are primarily regulated by the availability of nutrients and energy
What is top-down limitation?
Ecosystems are primarily related by consumption pressure from higher trophic levels
What is a trophic cascade?
The rate of consumption at one trophic level results in a change in species abundance or competition at lower trophic levels
What are the key biogeochemical cycles?
- Hydrological (water) cycling
- Carbon cycling
- Phosphorous cycling
- Sulphur cycling
- Nitrogen cycling
What is eutrophication?
Excessive plant and algae growth (caused by nitrogen and phosphorous fertiliser runoff)
