1. Review biomes

2. What is Ecosystems

3. 1.2 Ecosystems
Ecosystem – a part of a biome in which abiotic (non-living) factors interact with biotic (living) components
Can be many hectares of land, or the size of an old log.
Within an ecosystem, there are many habitats.
The habitat of the red fox often includes the edges of forests or marshlands

4. Abiotic Interactions in Ecosystems
It is the abiotic components that allow the biotic components to survive in an ecosystem.
Abiotic factors include :
Oxygen - produced by green plants & micro-organisms.
Water - necessary for all life.
Nutrients - for growth.
Light - required for
photosynthesis.
Soil - contains water &
nutrients.

5. Biotic Interactions in Ecosystems
Community: all organisms that interact within an ecosystem.
Population: all members of a certain species within an ecosystem.
Species: all organisms within an ecosystem that have the same structure & who can
reproduce with each other (and
produce fertile offspring).

6. (Ecological hierarchy)
Organism Species Population  Community Ecosystem
(Ecological hierarchy)

7. Organism
Species
Community
Population

8. Species can have many types of relationships in a population.
Symbiosis refers to the interaction between the members of two different species.
Commensalism - one species benefits, one is not affected
For example, the barnacles on a whale
Mutualism - both species benefit
For example, a bee gathering nectar from a flower
Parasitism - one species benefits, the other is harmed
For example, hookworm living in dogs

9. GROUP ACTIVITY : TYPES OF SYMBIOSIS ACTIVITY

10. Reading check p38 (Q1-4), p39 (Q 1-3)

11. Niches, Competition and Predation
Niche: the role an organism has within an ecosystem.
also refers to the environment in which a species prospers
Competition: occurs when a limited resource is desired by 2
or more individuals in a niche.
this limits the size & health of individual
organisms, & perhaps the population .
Predation: the relationship between the
“eaters” & the “eaten”.
Predators have adaptations to help them catch prey.
Prey have adaptations to help avoid predators.
Eg. spines & shells, camouflage and mimicry.

12. Predation
4000-
3000-
2000-
1000-
500-
300-
100-
25-
Number of hares per km2
Number of lynx per 100 km2
-20
-10 -0 10 20 30 40
Years

13. Biodiversity in Ecosystems
Biodiversity: the variety & number of different individuals & species in an ecosystem.
Healthy ecosystems generally have high biodiversity.
Most biodiversity losses occur from the loss of habitat.
Humans often have a negative
impact on biodiversity.
Ecological management
programs try to balance
human progress with
maintaining biodiversity.

14. Video on biodiversity

15. Check your understanding p51: 1,2,3,6,8,12
Reading check p47 (Q1-5)
Check your understanding p51: 1,2,3,6,8,12