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Ecology, Ecosystems, and the Environment

Ecology, Ecosystems, and the Environment. Chapter 19. Great Idea: Ecosystems are interdependent communities of living things that recycle matter while energy flows through. Ecology and Ecosystems. Ecology Branch of science focuses on natural living systems in the broadest sense Ecosystems

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Ecology, Ecosystems, and the Environment

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  1. Ecology, Ecosystems, and the Environment Chapter 19 Great Idea: Ecosystems are interdependent communities of living things that recycle matter while energy flows through.

  2. Ecology and Ecosystems • Ecology • Branch of science focuses on natural living systems in the broadest sense • Ecosystems • includes all different kinds of living things in a given area together with the environment • Ecosystems can be small or large. The emphasize is to look at the system –its energy and matter- as a whole, rather than a group of independent parts • Community • Producers –organisms that obtain atoms and energy form physical surroundings and convert them into Carbon-based molecule of life • Consumers – such as animals • Decomposers – Organisms, such as bacteria and fungi, that renew the raw materials of life in a ecosystem

  3. Characteristics of Ecosystems • Every Ecosystem consists of both living and nonliving parts • Energy flows through ecosystems • Matter is recycled by ecosystems • Every organism occupies an ecological niche • Stable ecosystems achieve a balance among their populations • Ecosystems are not permanent, but change over time

  4. The Carbon Circle

  5. The Law of Unintended Consequences • It is virtually impossible to change one aspect of a complex system without affecting other parts of the systems, often in as-yet unpredictable ways. • Examples: • Extracting petroleum and water from underground causes land subsidence; • Lake Victoria: largest fresh water lake in Africa • Nile perch – small fishes – algae and parasite bearing snails – hazard to lake and human • Roast Nile perch – wood – extensive soil erosion and other unintended changes A single new species has drastically altered a vast ecosystem.

  6. Threats to the Global Ecosystem and Environment

  7. The Problem of Urban Landfills • Solid Waste • Nothing is ever thrown away • 2000 vs 1986: increases of plastics and paper • Example: plastic bags • Landfills • Decay is very slow (newspaper readable after 50 years) • Response • Recycling • Large depositories in rural area

  8. The Ozone Problem • Ozone O3 • Absorbs ultraviolet radiation • The Ozone Layer • Stratosphere • Highest concentration

  9. The Ozone Problem cont. • The Ozone Hole • Concentration of ozone reduced • Yearly occurrence over Antarctica noticed in 1985 Linked to chlorofluorocarbons (CFCs) introduced in 1950s and used in aerosol spray and refrigerators / air-conditioners. • 2O3 + Cl +sunlight = 3O2+Cl • Dealing with the Threat to the Ozone Layer • Reduction of CFCs • Treaty of international congress meeting in Montreal in 1986

  10. Acid Rain and Urban Air Pollution • Burning introduces chemicals • Nitrogen oxides • Sulfur compounds • Hydrocarbons • Effects • Air pollution • Production of bad ozone • Acid rain • Reduction • Reduce emissions • Power plants • Vehicles

  11. The Greenhouse Effect • Greenhouse Effect CO2 absorbs heat but not light • Traps heat on earth • Global Warming • Climate change • Main points • CO2 is a greenhouse gas • Burning fossil fuels increases CO2 • Average global temperature has significantly increased • 1990s warmest decade

  12. Photographer’s Perspectives on Global warming (by Gary Braasch)

  13. Global Warming (by Gary Braasch) Upsala Glacier in Argentina: 200 m disappear annually Mount Hood in Oregan, same time 1985 and 2002 Rhone Glacier in Sweden decreases 2.5 km from 1859 to 2001 Water level of Tavalu Island in Pacific Ocean keeps on increasing

  14. Global warming （continue） Penguins in Adelie decrease 33% in the last 25 years。 Dry bottom of the lake in Florida Sea lives in Monterey Bay in CA move toward north More than 100 days of high temperature in ichuan, China, the hottest in more than 100 years.

  15. Global Warming and increasing of CO2 in atmosphere

  16. Debates About Global Climate Change • Is the temperature increase short-term or long term? • Is the increased CO2 levels really responsible for temperature increase? • Dealing with the Green House Effects

  17. Renewable Energy: Solar and Wind, etc Solar Water Heater Wind Turbines for Electricity Solar Electric System

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