thomas malthus’s essay was about: he claimed that the human population was growing faster than...
TRANSCRIPT
HUMAN POPULATION GROWTH & NATURAL RESOURCES
EARTH’S CARRYING CAPACITY
Thomas Malthus’s essay was about: He claimed that the
human population was growing faster than Earth’s resources could support.
EARTH’S CARRYING CAPACITY
Drawing of Figure 16.1 World Population:
EARTH’S CARRYING CAPACITY
What are renewable resources? Resources that cannot be used up or can
replenish themselves over time. Examples: wind, water, sunlight
EARTH’S CARRYING CAPACITY
What are nonrenewable resources? Resources that are used
faster than they form Examples: coal, oil, natural
gas
THE STORY OF EASTER ISLAND
1. Easter Island before people arrived on the island.
THE STORY OF EASTER ISLAND
2. Islanders started building the Easter Island Statues.
THE STORY OF EASTER ISLAND
3. Islanders cut down trees to make boats and shelter.
THE STORY OF EASTER ISLAND
4. Lack of trees causes erosion of nutrient rich soil. The soil washed into the ocean.
THE STORY OF EASTER ISLAND
5. Islanders run out of resources and are forced to leave the island.
THE STORY OF EASTER ISLAND
6. Today Easter Island is covered with grass, no trees, and the famous Easter Island Statue heads.
THE STORY OF EASTER ISLAND
What is an ecological footprint? The amount of
land needed to produce and maintain enough food, water, shelter, energy, and water.
ECOLOGICAL FOOTPRINT EXTRA CREDIT http://www.footprintnetwork.org/en/ind
ex.php/gfn/page/calculators
THE STORY OF EASTER ISLAND
Which continent has the largest human population? Asia
THE STORY OF EASTER ISLAND
Which continent has the largest ecological footprint? North America
THE STORY OF EASTER ISLAND
Which continent has the most level (close to equal) population to ecological footprint? Central &
South America
THE STORY OF EASTER ISLAND
What things can you personally do at home and school that can help save resources? You answer!
THE STORY OF EASTER ISLAND
Why is our ecological footprint related to an area of land? Land is needed to
support a population because we need land to support a lifestyle (a place to live, work, land for agriculture, a place to put waste that supports this lifestyle)
AIR QUALITY – ACID RAIN
What causes this problem?
What ecological problems does it
cause in the environment?
What can people do to prevent or
stop this problem from
occurring?
• Pollutants in the water cycle cause the pH of rain to drop.
• Lowers the pH or a lake or stream – affects organisms living there.• Can harm trees.
• Stricter laws on factory emissions.• Drive less.
AIR QUALITY – ACID RAIN
AIR QUALITY – OZONE DEPLETION
What causes this problem?
What ecological problems does it
cause in the environment?
What can people do to prevent or
stop this problem from
occurring?
• Ozone absorbs UV light• CFC’s used in refrigerants, aerosol cans destroy the ozone layer.
• More harmful rays of UV exposure.• UV light causes cancer.
• Decrease use or production of CFC’s
AIR QUALITY – OZONE DEPLETION
AIR QUALITY – GLOBAL WARMING (GREENHOUSE EFFECT)
What causes this problem?
What ecological problems does it
cause in the environment?
What can people do to prevent or
stop this problem from
occurring?
• Water vapor, methane, carbon dioxide.• Greenhouse effect
• Climate change, loss of habitat.
• More strict regulations for production of greenhouse gases.
AIR QUALITY – GLOBAL WARMING (GREENHOUSE EFFECT)
WATER QUALITY – BIOLOGICAL MAGNIFICATION
What causes this problem?
What ecological problems does it cause
in the environment?
What can people do to
prevent or stop this problem
from occurring?
• Pollutants that are water soluble and will stay in the body fat of an organism.
• Concentrations of a harmful substance accumulates to dangerous levels.
• Stop the use of DDT pesticide.
WATER QUALITY – BIOLOGICAL MAGNIFICATION
WATER QUALITY
Explain how biological magnification works using the picture:
WATER QUALITY
What other water related problems do we experience in Southern California?