Chapter 18 Introduction to Ecology

1. Chapter 18Introduction to Ecology Biology I Mrs. Schalles

2. ECOLOGY? - comes from the GREEK Words: OIKOS(HOUSE where one lives)LOGOS (STUDY) Ecology is the Study of the “House” in which We Live.

3. Ecology can be defined more specifically as: • The Study of the Interactions between: • Living Organisms • Non-living Components of their Environment.

4. Parts of the Environment: • Biotic-Living Organisms -Producers, Consumers, and Decomposer • Abiotic- Non-living components -sunlight, temperature, humidity, water supply, soil type, mineral nutrients (Nitrogen, Phosphorous, Sulfur, etc)

5. Interdependence - Effects of Interactions between organisms & their environment. - Each organism Depends in some way on other living and nonliving things in its Environment.

6. Key theme of Ecology • No Organism is isolated- Everything is interconnected • Species interact with each other & with abiotic factors in the environment. • Disturbances in one species can affect other species.

7. Example of Interdependence: • See diagram on page 360 in textbook • Unexpected “chain reaction” • In a year when more acorns are produced- eventually see humans with more lyme disease. • Explain how this happens. • Can you think of another example of how a change in your environment can indirectly affect living organisms?

8. Some examples of complex, controversial interactions are not completely understood : Because they involve: • dynamic ecosystems • multiple governments • differing interpretations of data in an area of ever-changing science.

9. Some Environmental Problems 1. Human Population Growth 2. Mass Extinction 3. What is Climate Change/Global Warming? 4. Pollution 5. Use of Resources/ Burning Fossil Fuels 6. Sustainability

10. 1. Human Population Growth Graph of Human Population Growth

11. 1. Human Population Growth Growth-limiting factors • the availability of food and water • invasion of parasites, pathogens or disease • over-crowding (increasing competition for food, water and space) • severe or sudden climatic changes • pollution of air, soil and water

12. 2. Mass Extinction • As human population has increased, many other species decline in number or become extinct. • There have been at least 5 periods of mass extinction, could we be causing # 6?

13. 3. What is Climate Change/Global Warming? What is the greenhouse effect?

14. 3. What is Climate Change/Global Warming?

15. 3. What is Climate Change/Global Warming? Major Greenhouse gases and their sources • H2O (water vapor) – evaporation, plant respiration. • CO2 (Carbon dioxide)- burning fossil fuels, volcanic eruptions • CH4 (Methane) -animal waste, fossil fuels, landfills, sewage, wetlands • N2O (Nitrous Oxide) – deforestation, fossil fuels, microbe activities (in soil) • CFCs (Chlorofluorocarbons)- aerosols, propellants, solvents, refrigerants

16. 3. What is Climate Change/Global Warming? Is Global Warming actually happening? • Many scientists say NO! • The Cooling World- Newsweek, April 28, 1975 • ( scientists warned in the 1970’s that the earth was dangerously cooling! www.denisdutton.com/cooling_world.htm • 1980’s-2006 Global Warming was the politically correct topic • See Al Gore & many Hollywood actors opinions. • In 2007, hundreds of people died, not from global warming, but from cold weather hazardshttp://www.washingtontimes.com/article/20071219/COMMENTARY/10575140 • 2008– Independent study commissioned by congress • Mr. Wegman& team from George Mason University concluded that the idea that the planet is experiencing global warming "cannot be supported."http://www.washingtontimes.com/apps/pbcs.dll/article?AID=/20080314/COMMENTARY/702895001/home.html

17. 3. What is Climate Change/Global Warming? Concerns if there were global warming: • Ecosystem interactions between predator & prey may change • Change in breeding times • Human health issues for increased mosquito population. • Rising sea levels • Coral Reefs

18. 3. What is Climate Change/Global Warming? If Ice caps were to melt- Rising sea levels would be a concern to islands like the Maldives.

19. 3. What is Climate Change/Global Warming? Coral reefs, the nurseries of many marine species, would be killed by higher temperatures, or by a lack of sunlight as sea level rises.

20. 4. Pollution Pollution Issues: An average person may produce a ton of refuse in a year • a volume that rapidly overflows local dumps.

21. 4. Pollution Types of Hazardous Wastes • Dyes, Cleaners, Solvents • PCB’s (Polychlorinated biphenyls- from old electrical equipment) • Plastics, Solvents, Lubricants, Sealants • Toxic Heavy Metals ( Lead, Mercury, Cadmium, Zinc) • Pesticides • Radioactive Wastes

22. 4. Pollution Effects of Toxins on Health -Over 85,000 synthetic chemicals are in use today, many now known to cause cancer & damage to the brain, nervous, reproductive & human hormonal systems.-An estimated 3-4 million American Children live within one mile of at least one hazardous waste site. Toxicology- The study of the harmful effects of toxins on organisms

23. 5. Use of Resources/ Burning Fossil Fuels Non- Renewable Energy • Fossil Fuels- the remains of ancient organisms, changed into coal, oil or natural gas. -central to modern lifestyle. • 2 BIG Problems: • (1) Supply is limited • (2) Environmental Consequences * March 2008- over 100$/barrel FUEL RESOURCES What is a sustainable energy source for the future???

24. 5. Use of Resources/ Burning Fossil Fuels Projected oil production: http://www.almc.army.mil/alog/issues/JulAug99/MS406c2.jpg

25. 6. Sustainability Alternative Energy Sources(Renewable Energy) • Nuclear Energy • Solar Energy • Wind Power • Biomass (methane, ethanol) • Hydroelectricity-water power • Geothermal Power- from inside the earth • Hydrogen Power- • Tidal Power- using water power for turbines • OTEC (Ocean Thermal Energy Conversion)

26. In Ecosystems- all things are connected • To appreciate how an ecosystem works- think about other things depend on hundreds of individual parts. • If one part is missing or breaks, the entire thing does not work.

27. BIOSPHERE • The biosphere is the thin layer of the Earth’s crust with the atmosphere & ocean layers that support LIFEthat includes: • All plant and animal life • The things that sustain life: air, soil and water. • It includes a variety of ecosystems that are connected by natural cycles.

28. Biosphere- is composed of three parts: • ATMOSPHERE – a light blanket of air enveloping the earth, with more than half its mass within 4 miles of the surface and 98% within 16 miles • HYDROSPHERE --- the surface and subsurface waters in oceans, rivers, lakes, glaciers, and groundwater, • LITHOSPHERE --- the upper reaches of the earth's crust containing the soils that support plant life, the minerals that plants and animals require for life and the fossil fuels and ores that humans exploit.

29. Earth Age: About 4.5 Billion Years OldLocation: In the Solar System, on the outer edge of the Milky Way, about 28,000 light years from the galactic center

30. Some Earth Facts: • Highest Point: 29,028 feet above sea level, Mount Everest, formed 60 million years ago, located on the border of Tibet & Nepal in the Himalayas (Asia). • Lowest Point (on Land): 1,320 feet below sea level, Dead Sea, (middle east) It is so salty -- the saltiest on Earth -- that it is unable to support any type of life. • Deepest Point on Earth: 35,802 feet, Mariana Trench in the Pacific Ocean. The water pressure there is over eight tons per square inch.

31. Some Earth Facts: • Surface Data: 70% covered by water, with the remaining 30% composed of the 7continental land masses. • Water Composition: • 97% salt water, 3% fresh water • (about 2% Is glaciers/ice & only.3% of all water is usable). • Air Composition: • 78% nitrogen, • 21% oxygen, • 1% other content

32. Hierarchical Levels of Organization-Ecology • Just like the hierarchy of levels of organization in organisms, there are also levels of increasing complexity in the environment. • Each level has unique properties that cannot be identified just by studying a lower level. • Each level is influenced by the other levels.

33. Levels of Organization • ORGANISM-Simplest Level of Organization (1 living thing) • POPULATION- Includes all the members of the same species - that live in one place at a given time & make-up a breeding group. • COMMUNITY- Includes all the interacting populations in one area. • ECOSYSTEM- Includes all the living (biotic) & non-living (abiotic) factors in the environment. • BIOSPHERE- Thin layer of life around the earth.

34. Levels of Organization

37. Examples of populations: All the bacteria of one All the gorillas of 1 kind on this agar plate species on this mountain Example of community: All the organisms living Together in this pond

38. A Changing Environment • Abiotic Factors do not remain constant • Organisms are able to survive in a range of conditions. • Most individuals can survive average conditions

39. Tolerance Curve • A graph showing performance vs. values for a specific variable such as temperature for a species. (See page 364 textbook) Example: Some bacteria can survive boiling water, some plants can survive arctic cold. But- Most organisms can not survive BOTH extremes.

40. Acclimation • Some organisms can adjust their tolerance to abiotic factors. • Examples- YOU adapting to less oxygen in higher altitudes • Goldfish, adapting to new water temperature • Conformers-organisms that do not regulate their internal conditions • Examples- Lizards, cold blooded organisms • Regulators- Organisms that use energy to control some of their internal conditions to optimum range in a variety of conditions.

41. Escape from unsuitable conditions Ways organisms cope with changes: • Dormancy • Hibernation • Estivating • Migration • Encysting

42. An Organism’s Relationship to the Environment Niche- The way of life of an organism -the status of an organism in its environment & community (affecting its survival as a species). -a position particularly well suited to the organism that occupies it. - An organism’s “PROFESSION” - Includesboth biotic and abiotic factors

43. The Niche includes: • the range of conditions that the species can tolerate, • the methods by which it obtains needed resources, • the number of offspring it has, • its time of reproduction • and all its other interaction with its environment.

44. Earthworm Niche

45. Generalists & Specialist Niches GENERALIST are species with Broad Niches; they can tolerate a range of conditions and use a variety of resources. example: opossum- eats a lot of different things SPECIALIST. Species that have narrow Niches, such as the koala, who only eats 1 kind of leaf.

46. Energy Transfer: from producers to consumers • Producers- are Autotrophs that manufacture their own food. (grass, plants, phytoplankton) • Creates Biomass(all the organic material in an ecosystem) • Biomass is the stored energy- the food for the rest of the organisms • Consumers- have to eat something (deer, bear) http://www.ftexploring.com/ftimages2/dr_br1.gif

47. Net Productivity • Measuring Productivity • Gross primary productivityis the rate at which producers in an ecosystem capture the energy of sunlight & organic compounds. • The rate at which biomass accumulates is callednet primary productivity. • different BIOMES (Places w/ a distinct climate like the tropical rain forest or the desert) produce different amounts of biomass.

48. Food Chains and Food Webs • A single pathway of energy transfer is a food chain. • A network showing all paths of energy transfer is a food web. -Trophic level- an organism’s relative position in the sequence of energy transfer in a food chain or web(who eats what) • Producers …………………… very many in # • Primary Consumers …………….many • Secondary Consumers …………..fewer • Tertiary Consumers…………fewest # organisms

49. Food Chain & Food web in an Antarctic Ecosystem

50. Energy Transfer • Ecosystems contain only a few trophic levels because there is a low rate of energy transfer between each level.