Transcript What is an Ecosystem?

Where is the Environment?
What is an Ecosystem?
• A community of different species
interacting with one another and with the
abiotic environment
Abiotic = non-living Biotic = living
Community = groups of populations
Population = group of organisms
Organism = living thing
Linkages: Humans are Part of Ecosystems
• Our Intelligence distinguishes us from other
species, but we basically play the same role as
other species within ecosystems
• clean air, water and soil
• continuing supply of plant and animal
products to consume for energy
But…we can do things like this
• There is only one
species that has the
ability to alter
ecosystems and
landscapes on a scale
similar to humans…
The world’s largest beaver dam is in Wood Buffalo
National Park – 850 m long
• We use resources faster than the biosphere can
renew them
Biosphere  the part of the Earth inhabited by plants and
animals (all communities on Earth)
• We need to sustain environmental resources so
they will be available in the future
• We need to realize that we are a part of the
environment. We need it, it doesn’t need us.
• The use of one environmental resource always
affects the status of another resource or
ecosystem either immediately of in the longer
term
The Human-Environment Connection
Disposal of Waste?
Resources for
Energy
Clean Air
Resources for
Shelter
Human Needs
Soil for
crops
Clean water
Major Causes of Environmental Problems
The Big Three
And
HIPPO
(1) – enviro damage occurs simply because there
are so many people on Earth
- the last 150 years has seen a dramatic increase in
population
- ~7.2 billion people on the planet today!
- ~ 9 billion by 2050
- There is competition between people for water,
land and food
- ~ 110 000 die each day by starvation
Which is more important, the survival of people
alive today, or the conservation of the
environment for people alive in the future?
(2) A resource is anything useful, that serves
our needs and is available at a price we
are willing to pay… are there free
resources?
Types of Resources:
i)
Renewable – eg. Forest,lobsters. They are
replaced by environmental processes
- as long as they are not used too quickly
they will meet our needs into the future
ii) Non-renewable: there is a limit to their
supply. eg. Fossil fuels
iii) Flow Resources:ones that must be used
where they are
eg. Solar, wind, water
- 20% of the worlds population consumes
80% of the worlds resources
- Canada is one of the biggest energy
consuming country on Earth WHY?
• But there are less dramatic but longer –
term releases of toxic chemical, sewage,
carcinogens, pesticides, nuclear
contamination, acid rain… all harm oceans,
lake, rivers, soil and atmosphere
• They cause: dead fish, vanishing species,
beach closures, dying lakes, forests, birth
defects, nervous system problems, and
cancer
Pollutant  any substance that adversely
affects the physical, chemical or biological
quality of the Earth’s environment
There are different perspectives on the future of our
world. Five commonly held visions of the future are
presented below.
• 1. Business as usual: There is nothing new under
the sun. The world has problems, always did and
always will. We will always have challenges but
nothing that we can’t work through.
• 2. Deepening crisis: Our world is in deep trouble.
It might be because of a nuclear war, a major
famine, a breakdown of law and order, or an
environmental crisis. Life will never be the same
again.
• 3. Governmental intervention: Authoritarian
leadership is required to save our society.
• Our government needs strict control to prevent
population growth and to stop pollution.
• 4. Technological innovation: Science and
technology have improved nutrition.
Consequently, humans are living longer. Investing
more in scientific research and technological
development will solve our current problems.
• 5. Sustainable society: It is necessary to rethink
our mechanistic and fragmented view of the
world. A more holistic and ecological perspective
is required so that a more humane and sustainable
society is possible.