Essential Idea:
Changes in community structure
affect and are affected by organisms
Understandings:
- Most species occupy different trophic levels in multiple food chains
- A food web shows all the possible food chains in a community
- The percentage of ingested energy converted to biomass is dependent upon the respiration rate
- The type of stable ecosystem that will emerge in an area is predictable based on climate
- In closed ecosystems energy but not matter is exchanged with the surroundings
- Disturbance influxes the structure and rate of change within ecosystems
Applications:
- Conversion ratio in sustainable food production practices
- Consideration of one example how humans interfere with nutrient cycling
Skills:
- Comparison of pyramids of energy from different ecosystems
- Analysis of a climograph showing the relationship between temperature, rainfall and the type of ecosystem
- Construction of Gersmehl diagrams to show the inter-relationships between nutrient stores and flows between taiga, desert and tropical rainforest
- Analysis of data showing primary succession
- Investigation into the effect of an environmental disturbance on an ecosystem