1
• Earth’s human carrying
capacity is unknown
• Technology has helped to
increase Earth’s carrying capacity.
– gas-powered farm
equipment
– medical advancements
– clean water
2
– public assistance
• Over 6.6 billion people
• Many natural resources are
nonrenewable
– Fossil fuels take millions of
years to form
• More people means:
– 1) More forests removed
– 2) More resources consumed
– 3) More CO2 released
3
4
• The growing human population puts pressure on Earth’s
natural resources
• Nonrenewable resources •
are used faster than they
can form or be replenished:
– Coal
– Oil
– Natural Gas
Renewable resources cannot
be used up or can replenish
themselves over time :
– Wind
– Solar
5
– Water
Ecological Footprint
• Defined: the amount of
land needed to support a
person.
• The land must produce and
maintain enough
– food and water
– shelter
– energy
– waste
• Several factors effect size:
– Amount/efficiency of
resource used
– Amount/toxicity of
waste produced
6
7
Ozone Layer Depletion
• Ozone Function: Block
UV radiation from sun
• Cause:
– CFCs (air pollution) thin
the ozone layer
– More UV radiation
reaches the surface
UV
UV
Ozone
Ozone layer
layer
• Effects:
– Crop damage
– Skin cancers
– Eye damage
• Solution:
– Reduce/Regulate CFCs
– Plant trees
CFCs
8
Smog and Ground-Level Ozone
• Causes:
– Burning of fossil fuels &
industry
• Particulates rise into air
and react with sunlight to
make air pollution
• Effects:
– Ozone gas (O3)is poisonous
– Respiratory illness
• Solutions:
– Reduce use of fossil fuels
– Alternative energy sources
– Plant trees
9
The Greenhouse Effect
• G.H.E. is naturally good (it
warms Earth)
• Causes: CO2 from burning
of fossil fuels (coal, oil,
natural gas)
• Effects: Excess heat
trapped near the earth’s
surface may change global
climate patterns; ice caps
melt
• Solutions: Reduce use of
fossil fuels, plant trees,
alternative energy sources
10
What’s a Greenhouse?
A Greenhouse is
designed to trap
heat so you can
grow plants year
round, even in
cooler
environments.
Some heat
escapes the
greenhouse,
but enough is
trapped to
keep the
inside warm
Some heat
escapes into
space
The Natural Greenhouse
Effect is good for life on
Earth.
CO2
Some heat
CO2
naturally trapped
by CO2 and other
CO2
greenhouse
gases
CO2
CO2
CO2
CO2
heat
CO2
CO2
CO2
Earth
CO2
CO2
CO2, Methane, other greenhouse gases
More heat trapped
near Earth’s
surface
Less heat
escapes into
space
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
CO2
heat
Excess CO2
in
atmosphere
CO2
Earth
The Greenhouse Effect is naturally GOOD!
Mars: No Greenhouse
Effect
Earth: Balanced
Greenhouse Effect
Little heat is trapped
by the thin CO2
atmosphere. High
temperatures can be
around 20⁰F.
Average global
temperature is 57⁰F.
Venus: The Extreme
Greenhouse Effect
Heat is trapped by
the thick CO2
atmosphere.
Temperatures
reach 750⁰F.
15
• Defined: Precipitation with a
below normal pH
• Cause:
– Fossil fuel pollution rises
into the air & then falls as
rain
• Effects:
– Waterways more acidic
– Kills plant and animal life
• Solutions:
– Reduce fossil fuel usage
– Add buffer (base) to
16
waterways
Nitric
acid
SO2
NO
NO
Sulfuric
acid
• Defined: pollution in water
supplies
• Causes:
– Waste
– Medicines
– Agricultural Runoff
– fertilizers
– pesticides
• Problems:
– Species lost
– Ecosystems harmed
• Solutions:
– Manage waste
20
• Indicator species:
Give sign of ecosystem’s health
• Example:
• Amphibians
• Frogs are good
indicator species
because their skin is
water permeable.
• Top predators
• Solution: Waste Management
21
• Defined: Accumulation of
toxins in the food chain
• Fat soluble pollutants
move up food chain.
– These pollutants stay
in the body fat of an
organism
– Predators eat
contaminated prey
– Pollution accumulates
at each level of the
food chain
• Top consumers, including
humans, are most
affected.
22
Deforestation
• Defined: Clearing of
forested areas
• Causes:
Harvesting/destroying
forests for high demand:
– Wood products
– Creating farmland
• Effects:
– Species lost
– Excess CO2 released
• Solutions:
– Recycle
– Improved farming
23
techniques
24
Introduced & Invasive Species
• Defined: Foreign organisms are
introduced to a new habitat
– Invasive: harms native species
• Cause:
– Foreign species introduced to
new environment
• Effects:
– Foreign species outcompete
native species
– Food webs unbalanced
– Economic damage
• Solutions:
– Laws preventing foreign goods
into new countries
– Introduce predators
25
• The Environmental Protection Agency
(EPA)
– Created in 1970
– Works to protect species
• Clean Water Act
• Clean Air Act
• Endangered Species Act
– This recovered the bald eagle
– Those listed are called “Umbrella
Species”
– Entire habitats protected
26
Review
1) CFCs are manmade chemical responsible for the destruction of the
2) Which gas is a main contributor to the greenhouse effect?
3) Crop damage and cancers are caused by an excess amount of which type of
energy? __________________
4) Name the big three fossil fuels:
5) Which planet has excess temperatures because of a thick CO2 atmosphere?
6) What is smog?
7) How are pollutants passed through the food chain?
8) Where is ozone gas harmful to life?
9) Where is ozone gas helpful to life?
10) What makes a resource nonrenewable?
11) Food webs become unbalanced as a result of the introduction of which type of
organisms?
12) What is an umbrella species?