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Human
Resource
Use
Ecological footprint:
analysis of people’s
use of food & natural
resources & their
production of wastes
& pollution
-humans have
exceeded Earth’s
capacity to repair itself
- humans must learn
to live sustainably
Acid rain destroys living things. - pH of 5.0 no longer supports fish - populations of frogs & other amphibians are becoming extinct because their young cannot properly develop in low pH water.
A possible fix: capture the polluting
emissions.
- expensive to install “scrubbers”.
- polluter and the recipient of the
pollution are far from each other and
neither wants to pay the price
Ex—Canadians receiving U.S.
industrial pollution
Destruction of the Ozone Layer
- “Bad” ozone forms in lower
atmosphere when exhaust emissions
from cars and factories reach
sunlight (smog)
*is corrosive.
*In humans: irritates/damages
lungs, air passageways, eyes,
suppresses the immune system, and
aggravates heart disease.
- “Good” ozone (O3) is the ozone layer in the Earth’s outer atmosphere, which absorbs about 99% of all UV light before it reaches the Earth’s surface. * A hole in the ozone layer over Antarctica opens for 6 weeks during late summer and early fall. * A hole has also opened over the Arctic.
*Ozone in these areas is an average
of 50% thinner than 20 years ago. *Increased UV exposure has resulted
in increased incidents of skin cancer,
cataracts, and cancer of the retina.
-What is Destroying the Ozone Layer? *CFC’s or chlorofluorocarbons (freon) - once considered inert - used as coolants in refrigerating equipment, aerosols, styrofoam. *CFC’s stick to frozen water vapor over the poles changing O3 (ozone) to O2 (oxygen gas).
In the 1970’s CFC’s were thought to be inert and in 1985 when the ozone holes were discovered, people became concerned.
(FYI)
In the early 1990’s, the US and 92 other countries signed international agreements that banned CFC production.
(FYI)
G W The increase of
L A gases in the
O R air from fossil
B M fuels being
A I burned causes
L N more of the
G sun’s energy to be
trapped in the atmosphere. FYI,…
no need to copy.
Ecosystem Damage
Pollution
Society has always had a tendency
to assume that the environment can
absorb any amount of pollution.
Biological magnification: amounts of
toxins increase significantly each trophic
level in a food chain/web
Ex: DDT pesticide
- Outlawed in 1970’s
Pollution
- little regulation on the manufacture,
storage, and disposal of toxic and
carcinogenic chemicals. ex:
Switzerland 1986—In putting out a
warehouse fire, 30 tons of mercury
and pesticides ended up in the
Rhine River and flowed into the
North Sea; massive kills of aquatic
life both plants and animals.
Consuming Nonreplaceable Resources
endangered: in danger of extinction
extinction: death of every member of
the species
(Sorry to inform you that Jurassic Park isn’t a true story.)
Sustainable development: way of using
natural resources w/o depleting &
providing for human needs w/o causing
long-term environmental harm
- Quotas on how much fish you can catch
Isn’t
this an
ugly
fish?
Conserving Biodiversity
Conservation: wise management of
natural resources
- Try to protect entire ecosystems, not just
individual species
Biodiversity
-total of variety of all org’s in biosphere
Ecosystem diversity: includes variety of
habitats, communities, & ecological
processes in the living world
Species diversity: # of different species in
the biosphere
- Over 1.5 million species in world
Habitat fragmentation:
splitting of ecosystems
into pieces
habitat destruction =
damming a river,
draining swamps,
logging, clearing land
for agriculture or
buildings
-Other plants & animals
can even threaten species
diversity
Invasive species:
introduced species that
reproduces quickly
because their “new”
habitat lacks the pop.
controls that they have
“back home”
There are 3 kinds of nonrenewable
resources which are being consumed
at an alarming rate.
TOPSOIL
GROUNDWATER
FOSSIL FUELS
Loss of topsoil—made of organic
matter (subsoil consists of inorganic
particles and minerals)
- the US has lost ¼ of its
topsoil since 1950.
We have:
1)turned over soil to eliminate weeds
2)allowed overgrazing
3)practiced poor land management
- ex: strip mining
To limit erosion:
-plant vegetation on bare fields
-no-till drill
-build windbreaks
- build irrigation ditches
-contour plowing: plowing that follows
the contour of a slope rather than going
up & down
-terracing: carving steps along a hillside
- One way we have lost soil is through
mining in order to obtain minerals and
fossil fuels
Mining
3 types of mines:
1. Strip mines
2. Open pit mines
3. Shaft mines
strip mining: layers
of Earth are removed
to gain access to
minerals
- earthmoving
equipment pushes
soil away to
expose ore
Ways to minimize
environmental damage from
strip mining:
-treating & containing runoff
-controlling emissions into the air
-re-vegetating mined areas
-replenishing topsoil that was removed
Open pit mining: dig a
big pit
-removes ore that starts
near the surface &
extends down for 100’s of
meters
Shaft mines: used to
mine ore in veins
-network of tunnels that
follow the veins
-mining can be bad for the environment!
-leaves scars on the land
-waste materials pollute rivers & lakes
-miners are required by law to replace
any top soil that is removed during strip
mining
Pollution and depletion of ground water
1)mostly trapped in porous rock
reservoirs called AQUIFERS
2)Large amounts wasted watering
lawns, washing cars, running fountains
3)if chemicals pollute it, there is
no effective way to remove the
pollution.
Solving Environmental Problems
AReducing Pollution
1.Many successes in the 1990s:
aWorldwide ban on CFC production.
bIn US, restricted or banned use of
DDT, asbestos, and dioxin
cAlso in the US:
1)Sulfur dioxide, carbon monoxide,
and soot were cut by 30% in 10 years.
2)Sewage treatment plants removal of
chemicals and bacteria has increased
by 72% in the last 12 years.
3)EPA estimates businesses and
private agencies are spending $100
billion per year on pollution control.
B Why Pollution is Profitable 1. A weak link in our economy of supply and demand is that businesses do not pass on all of the indirect costs in making a product. Ex—the cost of petroleum does not include all the money it would take to fix all the environmental problems created by extraction, shipment, refining, and use of petroleum products:
(FYI)
a reduced fish catches, b unusable lands, c air pollution resulting in damaged people (health), plants, buildings, d etc,etc,etc,etc. 2.All of these costs are passed on to future generations.
3. Pass Laws Forbidding Pollution --cars must have catalytic converters (breaks down toxic emissions)
4. Tax Things That Cause Pollution --increase cost of the product to hopefully reduce its use --cost can’t be so high that it inhibits industrial growth --can happen in the form of pollution permits that were first auctioned in 1993.)
1) Assessment—scientific analysis of what is happening; collecting data. Construct a model of the ecosystem and its response to your model. 2) Risk Analysis—use scientific analysis and predict consequences of intervention; both good and bad.
3) Public Education --explain problem, list possible solutions, results, and costs. 4) Political Action --special interest groups, write letters, and vote. 5) Follow Through --watch to see if the environmental problem is being acted on.
b Reduce personal use of resources,… carpool, bicycle, walk, use public transportation, turn your heat down in the winter, and have a warmer home in the summer, turn off lights when you leave the room, etc, etc, etc.
HERE’S AN IDEA,…