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Changes in Ecosystems. Chapter 7 Lesson 5. How Do Ecosystems Change. Ecosystems change over time. Some changes are natural, and they might happen slowly or quickly. Humans also cause change in ecosystems. Natural Changes. Mt. St. Helens Example. Natural Disasters.
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Changes in Ecosystems Chapter 7 Lesson 5
How Do Ecosystems Change • Ecosystems change over time. Some changes are natural, and they might happen slowly or quickly. Humans also cause change in ecosystems.
Natural Changes • Mt. St. Helens Example
Natural Disasters • Natural disasters can change ecosystems quickly • Ex: Volcanic eruptions, Earthquakes, Fires, Landslides, or Floods
Slow Changes • As the climate becomes warmer or cooler, the kinds of organisms that can successfully live will change. • Succession- a series of predictable changes that occur over time • What is a pioneer species? • The first species to appear in an ecosystem • Can live in harsh conditions
Continued • When pioneer species start to die, their decayed bodies help to make up the soil • After soil forms other species can live in the ecosystem. • Seeds may blow in, take root and begin to grow. • Those plants change the environment so that more plants can live there.
Beavers building dams can also be a form of succession. How? Pay Attention to the answer so you can copy it in your notes.
Human Impacts • An action as simple as throwing trash away can impact an ecosystem. • Where does all the human trash go? • Landfills! • Using landfills has advantages • They reduce odors and health hazards associated with open air dumps
Harmful Impact? • Landfills can have negative effects as well. • The waste or waste products can leak out and affect the ecosystem • Ex: paint, batteries, and other chemicals
Pollution • Every time fossil fuels are burned, we are harming our ecosystem • Pollutants enter the air • Carbon dioxide can cause changes in the environment
More Harmful Human Impacts • Overgrazing or over using land can be negative as well • Ex: Dustbowl • Fertilizers can also be harmful if the chemicals leak into water.
Saving Ecosystems • Some effects cannot be undone • Volunteering to help clean up after oil spills, natural disasters, etc. help the ecosystem • Many plants and animals will not recover from a major pollution disaster in their ecosystem • What are some more ways you can help?
Preventing Problems • One way you can help save an ecosystem is by understanding the effect that you have on the environment. • Use resources wisely • Conserve, recycle, reuse • http://www.youtube.com/watch?v=yZmpjzMWR7Q