Interactions Within Ecosystems

1
Grade 7 ScienceUnit 1

• Interactions Within Ecosystems
• Chapter 3

2
The Changing Ecosystem
3
(No Transcript)
4
(No Transcript)
5
Succession...

• A natural change of the ecosystem.
• It is the process by which a biological community
  changes over time. These changes may be slow and
  hard to see over short time periods.

6

• Pioneer species the first species to inhabit an
  ecosystem undergoing succession. Examples include
  lichens.
• Climax community the final community in the
  process of succession that remain unchanged for
  many years. The balsam fir is an example

7
2 Types of Succession...

• Primary Succession
• Takes place in areas lacking soil (bare rocks,
  sand dunes, and cooled lava for example)

8
(No Transcript)
9

• Secondary Succession
• The process by which an ecosystem changes after
  it has been disturbed by a fire for example.
• The re-growth of a community.

10
(No Transcript)
11
Discussion... Read p. 70-1

• Succession can have environmental changes such
  as...
• Soil composition
• Plant types
• Animal types
• Amount of light
• Explain

12
Core STSE

• The Two Centimeter Forest

13
The Human Impact...

• How do you think we have impacted our
  environment?
• Harvesting resources
• Habitat loss/ destruction
• Introduced species
• Pollution

14
Harvesting Resources

• The demand for natural resources has increased
  due to the increase in the human population.
• Our technologies have enabled us to remove the
  resources we need.

15
Habitat Loss/ Destruction

• Removing vegetation and soil removes shelter and
  food for animals.
• Changes on land alter drainage of water which
  affects rivers and lakes.
• See table 3.1 on p. 77

16
Introduced Species

• Species that have spread beyond their natural
  range into new locations as a result of human
  activities.
• Also called alien, exotic or non-native species.

17

• Can have negative impacts on the environment and
  affect ecological processes.

18
Ex. Of Introduced Species in NL

• Moose 1904
• Eastern chipmunk 1962
• Coyote
• Snowshoe hare 1860
• American mink 1934
• Deer mouse
• Norway rat
• Masked shrew
• American res squirrel 1963
• Bank vole

• Purple loosestrife
• English ivy
• Scotch broom

19

• Pine marten
• Wolverine
• Piping plover
• Eskimo curlew
• Longs braya
• Barrens willow
• Choose one of the above and tell its story.

• Endangered Species of Newfoundland Labrador

20
Pollution

• Substances that cause harm to the air, soil,
  water, or living things are called pollutants.
• Can have direct and indirect impacts on the
  environment.
• P. 82

21
Habitat Conservation

• Pros

• Cons

• Sustainability of resource
• Preservation of biodiversity
• Eco-tourism

• Artificial habitats
• Economic loss (job loss, etc.)
• Limited human use

22
Some environmental problems are not so easy to
solve.
23
The Decline in Cod StocksReasons?

• New fishing technology
• More demand
• Lack of conservation
• Unsustainable harvesting
• p. 80-1

24
Oil Slicks/ Spills
25
Acid Rain

• Caused by pollutants combining with water vapour
  in the atmosphere to produce acids.
• The acids fall as acid precipitation.
• NL is mostly granite rock. (unable to neutralize
  the acid)

26
Managing the Ecosystem

• Ecosystems must be monitored to detect any
  changes. Methods may focus on the
• Physical
• Chemical
• Biological
• Atmospheric

27
Long-term Monitoring

• Occurs over a period of many years.
• Important in managing species as it helps
  determine if the environment is changing in a
  significant way.

28
Groups Interested in Protecting the Environment...

• Local Examples
• Protected Areas Association
• Conservation Corps Newfoundland Labrador
• Shane Mahoney

29

• National Examples
• Parks Canada
• Canadian Native Federation
• Nature Conservancy of Canada
• David Suzuki

30

• International Examples
• Friends of the Earth
• World Wildlife Fund
• Ducks Unlimited

31
Predicting Change

• A goal of environmental monitoring. (ex. Climate
  change)
• Important for planning future developments.
• Environmental impact assessments are used to help
  make decisions prior to new development.