Transcript 5b. Chap 2- Human Impact TEA WCI 2015 - g9period4

ASSESSING
HUMAN IMPACTS ON
ECOSYSTEMS
“Why care?” Cubing activity
• In group of 4
• Use the provided 4-corner placemat
• Each member write down their own thought
after seeing each picture in the cube
Biodiversity
= the number and variety of
species on Earth
~ 2 million species identified so far
• To maintain biodiversity, we must
use the resources of an ecosystem
in a sustainable way
• Sustainable use: of an ecosystem
means using an ecosystem’s
resources in a way that meets our
current needs without
compromising the ability of future
generations to meet their needs.
What is Sustainability?
• The ability of populations
of organisms to live,
interact and reproduce
indefinitely in an
environment
Benefits of biodiversity and ecosystems
Food
-Fuel
-Natural resources
-Water
-wetlands purify water
- Regulate climate (temperature, rain)
-Cycle nutrients and decompose waste
-The animals help pollinate crops and disperse
seeds.
-Cultural and recreational opportunities (e.g.
parks, beaches) for our well being.
What causes biodiversity to decline?
Post- it Graffiti activity
Species at risks
Bee, Monarch Butterfly, Barn Owl, Cucumber Tree, Fowler’s
Toad, LakeSturgeon, and Wood turtle are all subject to
threats like habitat loss, pollution, roads, and invasive
species.
Learning Task
• To actively go through the provided
reading package and answer the
embedded articles.
• Respond to the exit card at the end and
obtain Ms. Pham’s initial
• Taken up next few slides
5 main reasons for the decrease in the variety
of species on Earth
• H = Habitat Change
• I = Invasive Species
• P = Pollution
• O = Overexploitation
• C = Climate Change
HIPOC
• NOTE:
• The next couples of slides you do not have
in your package
• They are used for assessment of what you
know after the reading on HIPOC
What impact is being implied
here?
Habitat Change
What impact is being implied here?
Overexploitation
“Which two factors that
affect biodiversity are
responsible for the possible
extinction of the Bornean
Rhinoceros?”
Answer:
1. Poaching
2. Habitat Loss
What impact is being implied here?
Overexploitation
What impact is being implied here?
Invasive (or
exotic) species
Gray vs. Red
1. List 2 reasons that the Gray Squirrel is such a threat to
the red squirrel.
carrier of squirrel pox and eat 7 times more
than that native red squirrels
2. What strategies is Britain using to solve the problem of
the gray Squirrel?
Allow gray squirrels to be hunted for meals
3. Do you agree with what Britain is doing? Can you
suggest other more humane methods?
What impact is being implied here?
Pollution
What impact is being implied here?
Climate Change
How did human pollution impact the ecosystem?
-Many marine organisms
mistake human plastic products
as food and consume them.
-They die after eating them as
they cannot digest them.
-Plastic products do not
decompose quickly; they
remain in the environment and
continue harming other
organisms.
http://www.ted.com/talks/capt_charles_moore_on_the_seas_of_plastic?language=en
How did human pollution impact the ecosystem? (Cont)
Causing acid rains
https://www.youtube.com/watch?v=v09KnqiYi-c
Hands-on: Simulate acid rain effect
What you need:
- Vinegar (filled to 3cm depth)
- 1 small test tube
- One 2-cm piece of chalk
• What did you observe?
• What would happen to this
statue if acid rain is falling on
it?
What is an acid?
• A corrosive substance
that have a high amount
of hydrogen ions
• An acid has a pH ranges
from 0 to less than 7
• pH is a measure of how
much hydrogen ions an
acid has.
Acidity Levels
• Acidity is an abiotic factor that is
connected to the chemical environment of
soil and water.
• If the pH of a substance is between 0
and 7 (below 7), it is called acidic. A
lower pH means higher acidity.
• If the pH of a substance is between 7
(higher than 7) and 14, it is called
alkaline (or basic).
• If the pH of a substance is 7, then it is
neutral.
Acid rain pH = 4.2
Clean rain pH = 5.6.
How did human pollution
impact the ecosystem? (Cont)
Causing acid rains
• In Canada, mining and refining
metals, electrical power
generation, automobiles, and
oil and gas operations emit
harmful chemicals made of
nitrogen and sulphur into the
atmosphere. This process is
called emission.
Statue corroded due to acid rain
• Acid Rain: rain that contains
acid formed from nitrogen and
sulphur containing substances.
Leafless forest due to acid rain
Ocean acidification- when excess CO2
dissolved in ocean
• Recall: ocean is
a carbon sink; it
stores CO2
Effects of acid rain on soils, vegetation, lakes, rivers,
and terrestrial and aquatic mammals
• Acid rain is an international problem as pollutant gases
are carried around the globe by wind
-Damages waxy coating
of plant leaves that
protect them from
infection.
-Acidic waters cannot support life:
dissolves shells of organisms,
makes fish eggs too fragile to
survive, and kills off aquatic plants
and animals.
-Reduces plant and tree
growth (increased acidity
towards the right)
-Increases acidity of soil
which decreases the plants
ability to absorb nutrients
from the soil.
-When acid rain seeps into
soil, it burns the skin of
earthworms.
HW
• Summarize table 3.1 p90 onto your note
• Do Question 1-3 page 94
Sing along