Post on 04-Jan-2016
Using Natural ResourcesOrganisms and Their EnvironmentEnergy and ResourcesPollution and Recycling
Objectives Explain the structure of an ecosystem Describe the effects one species can
have on an ecosystem Discuss two ways natural forces can
change ecosystems Discuss two ways humans can change
ecosystems
Key Terms Ecosystem Community Succession Hydroelectric power
Organisms and Their Environment What is an Ecosystem?
A mix of living and nonliving pieces of the environment
All ecosystems are not the same size The Earth is a very complex ecosystem A rain puddle is smaller and less complex
Living things are adapted to their ecosystem
Ecosystems are divided into communities, populations, and organisms
Organization:from large to small
Organisms and Their Environment Changes in Ecosystems
Factors can change an ecosystem Balanced ecosystems remain stable A change in one factor can affect the
whole ecosystem Sunlight, air, soil, water, animals, plants,
etc. Ecosystems will gradually return to their
original conditions Succession: repopulation over time
Succession
Organisms and Their Environment Evaluating changes in ecosystems
Short term changes, (the seasons) Long term changes, (volcanic eruptions) Climatic changes affect ecosystems, (ice
age) Changes can be caused by human activity
Building dams interrupt water supplies Changes can be caused by introduction of
nonnative species Birds, insects, amphibians are examples
Objectives Identify different sources of energy used by
living things and trace each source back to the sun
Describe the advantages and disadvantages of particular energy sources
Describe the types of conversion processes needed to produce electricity
Identify the efficiency of energy conversions
Key Terms Fossil fuels Nonrenewable resources Renewable resources Geothermal energy
Energy and Resources The search for resources
The sun is a source of energy Plants change energy from the sun into
chemical energy – converting solar to chemical
Fossil fuels form deep underground from once living matter, (dinosaurs, plants)
Fossil fuels can be solids, liquids, or gases The supply of fossil fuels is limited
Nonrenewable resources
Some see the supply of fossil fuels as a joke!
Energy and Resources Alternative sources of energy – renewable
Solar cells and solar power plants make electricity directly from sunlight
The energy of wind can be used by windmills The energy of water may be sued by
turbines in dams Geothermal energy may be collected from
“hot spots” in the Earth’s crust Nuclear energy is produced from atomic
fission
Renewable Energy Sources
Energy and Resources The efficiency of energy conversion
Energy is wasted when input is greater than output Wasted energy is generally found as heat
Wasted energy may be collected for further use Heat may be used to warm homes during
cold spells
Objectives Compare the economic and
environmental impacts of different energy sources
Identify pollutants created by use of fossil fuels
Describe types of pollution in air, water, and on land
Identify ways to reduce, recycle, and reuse.
Key Terms Pollution Global warming Eutrophication Recycling
Pollution and Recycling What causes pollution?
Natural causes – dust and ash Manmade pollution is more common –
(combustion) Air pollution
Combustion of fossil fuels carbon dioxide – one of the main pollutantsother pollutants are sulfur dioxide and nitrogen dioxide
Pollution and Recycling Water pollution
Pesticides and fertilizers May be found in quantities that make the water
“unfit” May cause eutrophication and kill water organisms
Pollution on the Land Contaminants in the soil are hard to remove
Some poisons stay in soil for long periods of time Landfill space is running out
Trash is the greatest pollutant on land
Pollution and Recycling Reducing pollution
Choosing alternatives often involves trade-offs Reusable grocery bags rather than paper or
plastic Reducing the use of energy and products
can cut down on pollution Turning off light switches when not in a room
Recycling is another way to prevent pollution Reusing materials to create new products