Transcript Man`s Impact on the Environment

Man’s Impact on
the Environment
Renewable Resources
 Resources that can be replaced
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Air
Water
Solar energy
Soil
Food
Although these can be replaced (takes a
long time) we must still use them carefully
Nonrenewable Resources
 Fossil Fuels- Oil,
Coal, Gas
 Minerals
 Metals
 Once they are
used up
(depleted) they
can not be
replaced
 What do you think is the main
overall cause of the current
environmental problems that
we face?
Population Growth
 Related to most serious environmental
problems
 More people = more resources, food,
waste, etc
 Rapid growth due to increased food
supply, better medical care, technology
 Earth’s carrying capacity reached soon?
 Famine, Disease, War due to competition
for resources (oxygen, water, space,
food)?
 Population control?
Population Growth
Industrialization
 Development of
economy using
machines which
need energy and
produce products
which may harm
environment
Pollution
 Industrialization
 Harmful changes in the chemical make up
of air, land and water
Air Pollution
 Wastes end up in the water cycle and
return to land
 Damage habitats , harm organisms
 Factories, cars, power plants burn fossil
fuels
 Carbon Dioxide, Sulfur, Nitrogen released
into atmosphere
Air Pollution
Acid Rain
 Sulfur and nitrogen + atmospheric
moisture = ACID RAIN
 Lower pH damages organisms- plants,
algae, fish eggs, etc.
 Food chains disrupted
 Property damage
Acid Rain
Smog
 Pollutants (automobile exhaust, industrial
processes) react with sunlight and get
trapped
 Dangerous to people w/respiratory
diseases, elderly, young children
Water Pollution
 Garbage, Sewage, Wastes (Homes,
Factories, Farms)
 Fertilizer inc. plant, algae, bacteria
growth  Oxygen supply dec. at night
(no photosynthesis)  organisms
suffocate, die  decomposers dec.
oxygen  oxygen-reduced ecosystem
Water Pollution
Thermal Pollution
Factories use water for cooling
Warm water does not hold as much
oxygen as cold water
Ozone Depletion
 Ozone shield- ozone gas layer in upper
atmosphere protects Earth from sun’s radiation
 CFC’s (chlorofluorocarbons)- coolants,
propellants, plastics released into atmosphere
destroying portions of ozone layer
 “Hole” lets in increased ultraviolet (UV)
radiation
- Cancer, cataracts
- Kills producers in ocean
 Food chains disrupted
Ozone Depletion
Global Warming
Global Warming
 Greenhouse Effect- Greenhouse gases trap
and absorb infrared radiation that is reflected
off Earth
 Increase of gases (CO2) from burning fossil
fuels cause inc. greenhouse effect  inc.
temperature  Global Warming
 Changed climate patterns- decreased food
supply
 Melting ice caps- rise in sea level, flooding
Global Atmospheric
Changes- Solutions
 International cooperation
 Ozone Depletion- International
agreements to reduce emissions of
harmful gases, product alternatives
 Global Warming- alternative energy
sources, increased forestation
Biological Magnification
 The concentration of a toxic substance
increases as it moves up a food chain
 Ex- Mercury accumulation in birds
 Ex- DDT accumulation in wildlife
Toxic Wastes
Biological Magnification
Biological Magnification
Habitat Destruction
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Land development destroys habitats
Displaced organisms have no home
Ecosystems are damaged
Species endangered, extinct
This tiger is endangered
She has lost her habitat
Habitat Destruction
 Deforestationdestruction of forests
for land use, building
resources,
manufacturing
 New York- wetlands,
forests, fields
 Rain Forestsdecreased
biodiversity
Biodiversity
 Wide variety of species in an ecosystem
 Decreased habitats  dec. species 
dec. biodiversity
 Food webs and ecosystems affected
 Atmospheric gases affected
 Future of drug industry and genetic research
affected
 Crops Rotation- different crops planted to
increase biodiversity
 Scientists have discovered a "treasure
trove of new species" including a frog
with a "Pinocchio-like" nose in a remote
section of Indonesian rainforest in
Southeast Asia.
Importation of Species
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Intentional or Accidental
No natural predators
Eliminate native species
Ex- Rabbits in Australia (24  billion)
Ex- Japanese beetles, gypsy moths
Transport laws, Quarantines, Pest
Control
Importation of Species
Direct Harvesting
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Removal of species from their habitats
Capture or Kill
Plants ,pets (parrots), ornaments (tusks)
May lead to death, extinction
Ex- passenger pigeons extinct due to
hunting, whales
 Laws protecting endangered species
Direct Harvesting
Positive Aspects
 Population Controls
Conservation of
Resources
Pollution Controls
Species Preservation
State Environmental
Protection Laws
Biological Controls
3 R’s for Preserving the
Environment
 Reduce- Avoid using resource
Ex- walk, bike, carpool
 Reuse- Use again instead of throwing
out
Ex- dishes not paper
 Recycle- Don’t put in trash, put in recycle
container
Ex- paper, glass, metal, plastic