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Chapter: Conserving Resources
Table of Contents
Section 3: The Three Rs of
Conservation
Section 1: Resources
Section 2: Pollution
• Limited availability
• Pollution : use of fossil fuels accentuates the greenhouse effect, contributing to global warming and ozone depletion
• Pollution compromises the health of the organisms living in certain areas
• Environmental impact: destruction of ecosystems during the extraction
• It can be costly and dangerous to extract fossil fuels
*Problems related to the use of Fossil Fuels
What will be the solution?
• Lower the use of fossil fuels by
increasing the use of alternative energy
resources – such as solar, wind, water,
tidal, geothermal power.
• Alternative energy sources will not
contribute to air pollution or to the
destruction of ecosystems
• Natural resources are the parts of the environment that are useful or necessary for the survival of living organisms.
• Ex: air, water, oil, coal, natural gas, energy from the sun
Natural Resources1
• A renewable resource is any natural resource that is recycled or replaced constantly by nature.
• Ex: Sunlight, water, air, crops, minerals that are part of organic matter that will decompose
( vegetation in general)
• Depending on the area, some can be in short supply – water in deserts
Renewable Resources
Resources
• Natural resources that are used up more quickly than they can be replaced by natural processes are nonrenewable resources.
• Earth’s supply of nonrenewable resources is limited.
• It is nonrenewable because it takes hundreds of millions of years for it to form
• Ex: fossil fuels such as oil, natural gas, coal.
• Metals and Minerals are also nonrenewable resources.
Nonrenewable Resources
• Many manufactured items are made from fossil fuels .
• Most of the energy we use comes from the burning of fossil fuels.
• Gasoline
• Plastic
• Products made of graphite, iron, copper, tin, gold, silver, uranium
Importance of Nonrenewable Resources
• Fossil fuels are sources of energy extracted from the environment.
• Fossil fuels are formed when the remains of dead organisms go through the process of decomposition and are kept under high temperatures and pressure.
Fossil Fuels
Resources
1
• Fossil Fuels are nonrenewable resources. Ex: coal, oil and natural gas
• Importance: most of the energy we use comes from the burning of fossil fuels.
Fossil Fuels
Resources
1
General information about Electricity
production
• Electricity is generated by converting
mechanical energy into electrical energy.
• To achieve this, you need a turbine to
move, generating mechanical energy
• Next, the mechanical energy will be
transformed in electrical energy in a
generator
• Different sources of energy are used to
move a turbine
• Very often, steam is used to drive these
turbines
• Water is turned into steam by the
burning of fossil fuels ( coal power plants
for example), by heat generated through
nuclear fission ( nuclear power plants),
by heat from magma ( geothermal power
plants.
• Other sources of energy: wind, tidal and
water from dams and nuclear
• Solar power:
• Will not use turbines. The
photovoltaic cells in the panels will
transform the energy from the sun
into electrical energy
• **Problem: expensive
Nuclear Power:
Uses the heat produced in nuclear fission reactions to produce stem and move turbines.
Nuclear fission splits atoms of Uranium generating high amount of energy.
Nuclear Power
Problems:
• uranium is a nonrenewable resource
• nuclear power plants also produce radioactive wastes that can seriously harm living organisms.
Tidal and Hydroelectric
Power Plants
• These power plants do not use steam.
The source of energy is in the fact that
the water is stored in large dams. When
the water is released, it has high
pressure that it will move the turbines,
producing mechanical energy.
Tidal Energy textbook page 736
The constant movement of ocean water
generates tides. This movement is a source of energy
that can be transformed in electricity
• It does not contribute to air pollution because no fuel is burned.
• However, it does impact the ecosystem around it.
• Building a hydroelectric plant or a tidal plant usually involves constructing a dam.
** Water Power
Many acres behind the dams are flooded, destroying land habitats.
Tidal basis will also affect the marine ecosystems and can only be built in areas where there is a high difference between the high tide and low tide.
Wind Power Plants:
The wind will turn windmill blades
connected to turbines, making them turn,
generating mechanical energy.
** Wind power does not cause air pollution, but electricity can be produced only when the wind is blowing.
Wind Power
** Wind power does not cause air pollution, but electricity can be produced only when the wind is blowing.
Geothermal Power Plants
• Uses the heat from magma to produce steam.
• Geothermal energy is available only where magma is close to the surface
Geothermal Reservoir
• Magma is close to the surface
• Water seeps down through cracks
• Magma heats this water and can form
steam
• Hot water and stem are trapped under
high pressure in pockets called
geothermal reservoirs
• Reservoirs close to the surface will form
geysers and hot springs
Chapter 19 - section 2
Pollution
**Definition:
Pollution is the presence or introduction
into the environment of a substance or
thing that has harmful or poisonous
effects.
Pollution affects the air, water and soil.
** Pollution – How to avoid
Pollution on the water, air and soil can be
reduced by:
1) Treating and recycling wastes
2) Reducing the burning of fossil fuels
**Sources of Pollution
• Emissions of greenhouse gases from vehicles,
industries, power plants
• Pollution from chemicals used in
agriculture
• Pollution from live stock farms
• Pollution from untreated or partially treated
sewage
• Pollution from hospital wastes
• Volcanic eruptions ( CO2 and gases that
contain Sulfur)
**Effects of Pollution
• Pollution lowers human health
• Causes environmental degradation – putting at
risk the biodiversity that exists on Earth
• Increases the levels of greenhouse gases in the
atmosphere
• Contributes to Global Warming and Ozone
Depletion
• Turns land infertile due to the extensive use of
chemicals in crops
1) What is a pollutant. Give examples
2) what is smog and how to avoid smog?
3)what is acid rain ?
4) what are the effects of acid rain?
5) how can we prevent acid rain?
6) Carbon monoxide is a poisonous, colorless and
odorless gas. What are the sources of CO in indoors
areas?
7) What is Radon?
8) what are the effects of radon and how to avoid it?
9) what are algal blooms and what are the
consequences of algal blooms?
10) what are hazardous wastes? Give examples
1) A pollutant is a substance that contaminates the environment.
Air pollutants include soot , smoke, ash, and gases such as carbon dioxide, carbon monoxide, nitrogen oxides, and sulfur oxides.
2) Smog is a form of air pollution created when sunlight reacts with pollutants produced by the burning of fuels.
• It can irritate the eyes
• It can make breathing difficult for people with asthma or other lung diseases.
Smog can be reduced by lowering the
amount of greenhouse gases in the air
Car pools
Use public transportation
Reduce emissions from the industry
4) Acid Rain is the result of the reaction of air pollutants from the burning of fossil fuels with water in the atmosphere.
• These reaction forms strong acids that will precipitate
• Acid Precipitation has a pH below 5.6 (vinegar – pH of 4)
5) Acid precipitation washes nutrients from the soil affecting the plants that need these nutrients
Runoff from acid rain that flows into a lake or pond can lower the pH of the water affecting aquatic life.
EX: If algae and microscopic organisms cannot survive in the acidic water, fish and other organisms that depend on them for food also die.
6a) Reduce the use of fossil fuels: Sulfur from burning coal and nitrogen oxides from vehicle exhausts are the pollutants responsible for acid rain.
6b) The use of low-sulfur fuels, such as natural gas or low-sulfur coal - can help reduce acid precipitation.
Problem: these fuels are more expensive
6 c)Smokestacks that remove the sulfur dioxide before it enters the atmosphere also help.
Smokestack - a pipe for the escape of the smoke or gases of combustion
7) Sources of indoor CO –
Fuel-burning stoves and heaters.
It is helpful to install alarms or
continuously ventilate indoor areas
8) Radon is a naturally occurring
radioactive gas given off by some rocks
and soil.
If can seep into basements and lower
levels of buildings
Colorless and odorless as CO.
9) Radon can cause lung cancer.
• It is important to use detectors and
ventilate the areas constantly.
10) Algal blooms results from high
amounts of Nitrogen in the water.
Nitrogen can reach the water with sewage
and fertilizers.
Nitrogen will increase algae growth.
The death and the decaying of the high
quantity of alga will consume too much
oxygen.
Rest of the life existing in the pond can die
due to the lack of oxygen
Alga – singular Algae – plural
11)Waste materials that are harmful to living organisms are hazardous wastes.
They include:
• Radioactive wastes from hospitals and nuclear power plants
• Infectious wastes from hospitals and other treatment facilities
• And…….
Hazardous Wastes2
• Dangerous chemicals: pesticides, oil, and petroleum-based solvents used in industry.
• Radioactive wastes from hospitals and nuclear power plants
Greenhouse Effect
Heat-trapping feature of the atmosphere that keeps the earth at an ideal temperature to support life
BUT: the burning of fossil fuels (pollution)
increases the greenhouse effect and can
contribute to Global Warming
Global Warming
A rise in Earth’s average temperature.
Consequences:
• Melting of polar ice caps causing flooding in certain areas, affecting ecosystems and populations
• Changing in Rainfall patterns
Ozone Depletion
The periodic thinning of the ozone layer in polar regions
This problem is caused by greenhouse gases called chlorofluorocarbons (CFCs).
CFCs react chemically with ozone, breaking apart the ozone molecules.
Consequences: a higher amount of harmful sun rays (UV) will reach the earth , affecting humans, animals and plants ( skin cancer, affect lungs of animals and sensitive tissues of organisms)
Chapter 19 Section 3
The Three Rs of Conservation
• It is important to reduce the amount of
trash we produce.
• According to the Environmental Protection
Agency, the average American produces
1,600 pounds (726 kg) a year of trash.
• This only takes into consideration the
average household member and does not
count industrial waste or commercial trash
TOP 10 COUNTRIES THAT PRODUCE
THE MOST WASTE
1) USA / other list brings Mexico as number 1
2) Russia
3) Japan
4) Germany
5) UK
6) Mexico
7) France
8) Italy
9) Spain
10) Turkey
Waste: Most solid waste is dumped in landfills.
Landfills are lined.
This helps prevent
pollutants from seeping
into surrounding soil.
If the landfill is poorly
constructed, hazardous
wastes can reach and
contaminate the water.
Wastes
• Gas produced from the decomposition of wastes in landfills is used as a renewable energy source.
• In certain areas landfills are not used increasing the risk of human and environment contamination.
Conservation
• Conservation is important to protect the environment and the population on Earth
• The three Rs of conservation are reduce, reuse, and recycle.
The Three Rs of Conservation
3
How do we reduce the use of natural
resources?
• walking,
• riding a bike,
• avoiding buying things you don’t need,
• look for products with less packaging,
• buy products with packaging made with recycled materials