Transcript IV_Humans_Alter_the_Biosphere_new.ppt

IV. Humans Alter the Biosphere
A. Food Production Causes Land Pollution
1. Agriculture (man-made monocultures) that
must be maintained by a high energy input in
fertilizers, pesticides and herbicides
2. Agro-Corporations have altered Food Production
Confined Animal Feed Operations
a) Cafos are cruel to the confined animals
b)
Large amounts of antibiotics are
needed to keep the animals alive in
such close proximity. This leads to
antibiotics in meat and drug resistant
bacteria.
c) Large Agro-businesses have
crushed family farms
d) Huge amounts of animal excrement
pollute ground water and streams
B. An Urban ecosystem’s largest product is
trash.
1. Existing landfills
are running out of
space.
2. Most communities
reject plans for
new landfills
3.
Landfills are not just holes in the ground.
a) Ground water must be monitored and protected from
contamination
b) Gasses must be collected or flared
c) Landfills are breeding grounds for disease organisms
4. Incinerators reduce trash volume but they pollute
the air. Further, the ash that remains is high in
toxins.
C. Water Pollution
1. Fertilizer runoff increases Eutrophicationincrease in the nutrients in water
a) Eutrophication results in
Algal Blooms (rapid
increase of algae
populations)
b) When the algae die,
decomposers use up
large quantities of
oxygen to break them
down
c) Aquatic organisms die
from lack of oxygen
2. Pesticide run off
accumulates in
the water supply
resulting in
Biological
Magnificationthe build up of
toxins as you
move up the food
chain
3. Our Fresh Water Supply is Limited
a) Of the 7 billion people on earth, 1.1 billion do
not have access to safe, clean drinking
water.
(www.charitywater.org)
b) California has about 20 years of water left in
the state. Maude Barlow, author of Blue Covenant and
co-author of Blue Gold,
c) Water is a $400 billion dollar global industry;
the third largest behind electricity and oil.
CBS News.
D. Air Pollution
1. Burning Fossil fuels (oil, coal and gas)
pollutes the air by releasing nitrous & sulfur
oxides, particulate, hydrocarbons
a) Particulates (soot) builds up
and covers buildings and
neighborhoods and can
cause respiratory problems
b) Sulfur and nitrogen oxides
combined with atmospheric
moisture and cause acid
rain
1) Acid rain destroys forests,
lakes and streams by lowering
the pH
2) Few living things can tolerate a
pH below 5
C. Hydrocarbons can cause the Greenhouse
Effect by preventing heat from dissipating
back into space
Data indicates atmospheric CO2 has
been increasing for the past 50 years
Red Indicates CO2 Emissions
Fossil Fuels are non-renewable and highly polluting.
World oil supplies could be depleted by 2050
As man clears more area for expanding cities and
agriculture, wildlife, both plants and animals, lose their
habitat
Loss of Habitat
a) loss of feeding and
breeding grounds can
result in extinction
b) Extinction- the
elimination of a
species from the
biosphere forever
c) If a species is
endangered it is near
extinction and if it is
threatened it is near
to being endangered
2. Nearly all medicines
were derived from a
plant,fungus, bacteria or
animal species
3. If we destroy many
species, we may lose
the genetic material we
need to cure cancer or
AIDS.
D. Possible Solutions
1. Natural fertilizers (garbage, manure) and
crop rotation with legumes can reduce our
dependence on chemical fertilizers
2. Recycling (metals, glass and paper) will
reduce the speed we are using up landfill
space. Garbage can be composted to
provide fertilizer.
3. Alternate Energy Sources (nuclear,
hydroelectric, solar, geothermal, wind,
waves) can reduce our use of fossil fuel