1. Interactions in Ecosystems
Unit 1:
Interactions in Ecosystems

2. Interactions within an ecosystem
Topic 1:
Interactions within an ecosystem

3. O2 CO2 The 4 basic needs of living things... food water
suitable habitat O2
gas exchange
CO2

4. Adaptations... There are 2 types of adaptations: 1. Structural
- a special body part that helps an organism survive
2. Behavioural
- a special behaviour that helps an organism survive

5. Ecosystems...
An Ecosystem is the interactions between living and non-living things in a particular environment.

6. Symbiosis...
When two species live closely together in a relationship that lasts over time.
Types of Symbiosis:
1. Mutualism
2. Parasitism
3. Commensalism

7. relationship when both partners benefit
1. Mutualism...
relationship when both partners benefit
Honeypot Ants tending Aphids
Ants use honeydew secretions from aphids and will aggressively protect the aphids (they may even move them when they are in danger)!
Ants benefit by getting the honeydew.
Aphids benefit from being protected by the ants.

8. Another example of mutualism...
Lichens are made up of an algae and a fungus.
Algae produce food for the lichens (through photosynthesis)
Fungi absorbs nutrients and water

9. Yet another example of mutualism...
Birds foraging for tiny parasites on the giraffe.
The birds benefit by getting food.
The giraffe benefits by getting rid of the parasites.

10. relationship when one partner benefits and the other is harmed.
2. Parasitism...
relationship when one partner benefits and the other is harmed.
Guinea worm inside a knee joint
hookworm

11. Another example of parasitism...
A lamprey clings to a fish.
The lamprey benefits because it gets its food from the fish.
The fish is harmed because it eventually dies.

12. 3. Commensalism
relationship when one member benefits and the other neither benefits nor is harmed
The fish eats tiny particles that are trapped in the anemone's tentacles.
The fish benefits because it gets food
The anemone isn’t harmed and doesn’t benefit

13. Human impacts on ecosystems
Topic 2:
Human impacts on ecosystems

14. Natural Resources...
are resources that are found naturally in nature.

15. Needs vs. Wants A need is something you need to survive.
A want is something that you wish that you had.

16. Wetlands
“purify” water
habitats for organisms
prevent flooding

17. Environmental Choices
Topic 3:
Environmental Choices

18. Ecological Footprint & Sustainability
Your ecological footprint is the calculation of the total area of land and water needed to supply all of the materials and energy a human uses (and to absorb the waste produced).
Sustainability means that the resources of nature are being renewed at least as quickly as they are used.

19. The 3 Rs...
1. Reduce
2. Reuse
3. Recycle

20. How Organisms Interact
Topic 4:
How Organisms Interact

21. Biotic vs. Abiotic Biotic factors = living parts of an ecosystem
Abiotic factors = nonliving parts of an ecosystem
Abiotic Factors
soil 02
CO2
water
Biotic Factors
butterfly
flowers
bacteria
other plants

22. Terms you need to know... producer
- an organism that makes its own food
consumer
- an organism that eats other organisms
decomposer
- an organism that breaks down decaying matter for food

23. More terms you need to know...
herbivore
- an organism that only eats producers
carnivore
- an organism that only eats other animals
omnivore
- an organism that eats plants and animals

24. Food Chains and Food Webs
A food chain is a model that shows how energy stored in food passes from organism to organism.
(the arrow always points to the organism that is getting the energy)
A food web is a network of interconnected food webs.

25. Niches vs. Habitats A habitat is… - where an organism lives
A niche is…
- the role that an organism has in its ecosystem

26. Pyramid of Numbers
is a model of an ecosystem that represents the number of organisms consumed at each level.
(there are always more organisms at the bottom of the pyramid than at the top)

27. Cycles in the environment
Topic 5:
Cycles in the environment

28. The Carbon Cycle
Carbon is continually being recycled in an ecosystem through the carbon cycle.

29. The Water Cycle
Water is continually being recycled in an ecosystem through the water cycle.

30. Important terms to know from the water cycle...
Evaporation:
- process where a liquid changes into a vapour
Transpiration:
- process where water that is taken in through a plant’s roots evaporates from the plant’s leaves
Condensation:
- process where a vapour changes to a liquid (making clouds)
Precipitation:
- process where liquid or solid falls to the earth
Ground Water:
- water in the soil
Run-off:
- water that runs off the ground into rivers, lakes or streams

31. pH pH is a measure of acidity on a scale of 1 to 14 1 - 6.9 = acidic
7 = neutral
= basic
(normal rainwater has a pH of about 5.6)

32. pH and the environment...
When fossil fuels are burned pollutants are produced that condense in clouds to make them more acidic.
When the clouds turn to precipitation and fall to the ground it is a form of pollution called acid rain.
If ecosystems have too much acid in them it can have a very serious negative impact on organisms in the environment.

33. Effects of acid rain...
on a forest
on a stream

34. More acid rain effects...
before acid rain
after acid rain

35. Acid rain on manufactured objects...

36. Bioaccumulation
movement of pollutants through levels of a food chain so that greater quantities are retained with movement up the food chain

37. Succession and change in ecosystems
Topic 6:
Succession and change in ecosystems

38. Succession
Primary Succession: the gradual growth of organisms in an area that was previously bare
Secondary Succession: the gradual growth of organisms in an area that was formerly home to many different species

39. break the rock down into soil
Primary Succession...
lichens on a rock
break the rock down into soil
so other organisms can live there

40. Secondary Succession...
A forest fire has cleared away the foliage around these trees.
These wildflowers are thriving in soil that has been burned by fire.

41. Succession in a Pond Ecosystem
A colony of beavers dam a stream, creating an open pond in the forest, and
the surrounding trees die.
Plants that like damp conditions thrive around the margins of pond.
As these plants complete their life cycle and die, they add to the accumulating organic matter which is making the pond shallower.

42. Some years, pond begins to dry out and pond-edge plants (cattails and sedges) take over inside of dried pond.
Around the ponds edges the plants are being replaced by shrubs.
the shrubs are replaced by trees

43. Controlling Pests...
Sometimes chemicals are used in order to control pests.
But this can seriously affect organisms in the ecosystem.

44. Biological Control
Often a better way of controlling pests is by using biological control...
using the pests natural enemies to control their populations

45. Introduced Species
Introduced species are organisms that are brought into an ecosystem in which they aren’t normally found.
We must be careful about what species we bring into ecosystems…they can cause a lot of damage.

46. Species in Danger
There are 5 different ways to describe species in danger:
Extinct
Species no longer exists
Extirpated
Species no longer exists in the wild in Canada, but occurs elsewhere
Endangered
Species is facing imminent extinction or extirpation
Threatened
Species is likely to become endangered
Vulnerable
Species is of special concern because it is very sensitive to human impacts

47. Environmental monitoring
Topic 7:
Environmental monitoring

48. Environmental Monitoring
Is a method of checking the condition of an ecosystem by comparing investigation results done at different times
There are different types of monitoring...
1. Ecosystem Monitoring
2. Physical Monitoring
3. Chemical Monitoring
4. Biological Monitoring

49. The Study...
Scientists need to collect Baseline Data
In order to determine what the ecosystem is like ‘normally’
Then they can set up Permanent Plots (quadrats) to study the area more carefully

50. Environmental Impact Assessments
One practical way scientists use ecosystem monitoring is to make...
Environmental Impact Assessments
To predict what kind of impact human activities may have on the environment
E. I. A.

51. Indicator Species
Are plant or animal species that help to indicate environmental change
Amphibians are often used as indicator species because they are very sensitive to change.

52. You have learned a lot of things in this first unit,
Good Luck, Have Fun and Enjoy the exam tomorrow!

53. The End