The Scope of Ecology

1. The Scope of Ecology Chapter 34

2. What is ecology? Ecology-the scientific study of interactions between organisms and their environments, focusing on energy transfer • It is a science of relationships. Oikos- greek for “house”

3. #16 • http://www.youtube.com/watch?v=izRvPaAWgyw • #16#14 (ecology rules of life CC)

4. Ecology is primarily a descriptive science but is becoming more experimental

5. 1.  very difficult to control experiments 2.  some research done in laboratories 3.  most done in the field

6. What do you mean by environment? The environment is made up of two factors: Biotic factors- all living organisms inhabiting the Earth Abiotic factors- nonliving parts of the environment (i.e. temperature, soil, light, moisture, air currents)

7. Interaction • interaction includes how the environment affects the organism and how the organism can alter the environment

8. Interaction • 1.     photosynthetic organisms use sunlight (abiotic factor) and produce oxygen as a bi-product which is used by organisms for cellular respiration

9. Interaction • 2.        shading of the forest floor by trees can make the environment less suitable for their offspring to grow, yet more suitable for other organisms

10. Levels of Ecology • ecological research ranges from studying adaptations of organisms to the dynamics of ecosystems

11. Organism-any unicellular or multicellular form exhibiting all of the characteristics of life, an individual. • The lowest level of organization

12. 1.  organismal ecology – study of the way organisms meet the challenges of abiotic environmental factors • e.g., reptiles retreat to shaded areas to maintain body temperature

13. Population-a group of organisms of one species living in the same place at the same time that interbreed and compete with each other for resources (ex. food, mates, shelter)

14. 2.        population ecology – study of populations and interaction with environment e.g., what environmental factors affect population size and composition?

15. Community- several interacting populations that inhabit a common environment and are interdependent.

16. 3.        community ecology – study of all organisms that inhabit an area • e.g., study of predator – prey relationships, competition, disease

17. 4.        ecosystem ecology – study of all abiotic factors as well as all organisms in an area • e.g., study of energy flow and chemical cycling among the biotic and abiotic components

18. Biosphere- life supporting portions of Earth composed of air, land, fresh water, and salt water. • The highest level of organization

19. 5. Biosphere ecology – studying the global system of living things • e.g. humans effect on the ozone layer or climate change

20. Biosphere Ecosystem Community Population Organism

21. Abiotic factors • temperature1.        most organisms are NOT able to regulate their body temperature; i.e., they’re ectothermic as apposed to endothermic 2.        temperature has a tremendous affect on metabolism3.        even endotherms function best within a temperature range

22. Abiotic factors • water 1. essential for life2. poses osmotic challenges for organisms

23. Abiotic factors • wind amplifies the effects of temperature by increasing heat loss and evaporation

24. Abiotic factors

25. Climate Weather over a long period of time most important components • Precipitation • Temperature • Wind

26. Convection Heat transfer in a fluid (liquid or gas) Heat rises The current formed is a Convection Cell

27. http://www.youtube.com/watch?v=5QOVwX-6g-Q • #81Video #76 (Global winds)

30. Desert Latitude 30 degrees N or S Cool dry falling air limits precipitation

32. Rain-Shadow Effect

33. Rain Shadow Effect Air flowing over mountain ranges rises and cools, losing moisture Climate is much dryer on the backside of the mountain range

34. Coriolis Effect Coriolis effect is the apparent curvature of global winds, ocean currents, and everything else that moves freely across the Earth's surface.

35. Videos##77,78,79Coriolis effect, Force, CC • http://www.youtube.com/watch?v=i2mec3vgeaI • # • http://www.youtube.com/watch?v=aeY9tY9vKgs • #83 • http://www.youtube.com/watch?v=rdGtcZSFRLk

36. "The tendency of a circulation in a fluid to develop in a clockwise direction in the Northern Hemisphere and a counterclockwise direction in the Southern Hemisphere can be traced to the earth's rotation. Imagine a cannon fired southward from any latitude above the equator. Its initial eastward motion is the same as that at a point on the spinning earth. This initial eastward velocity is less than that at a point later in its trajectory, because points closer to the equator travel in a bigger circle as the earth rotates. Therefore, the cannon shell is deflected westward (to the right), from the perspective of a person standing on the earth. A gunner firing a cannon northward would find that the shell is also deflected toward the right. These sideways deflections are attributed to the Coriolis force, although there really is no force involved--it is just an effect of being in a rotating reference frame."

37. The Coriolis force accounts for why cyclones are counterclockwise-rotating storms in the Northern Hemisphere, but rotate clockwise in the Southern Hemisphere. The circulation directions result from interactions between moving masses of air and air masses moving with the rotating earth. The effects of the rotation of the earth are, of course, much more pronounced when the circulation covers a larger area than would occur inside your bathtub.

45. Northern Hemisphere- everything turns right causing counterclockwise rotation of weather systems

47. Polar Easterlies Westerlies Northeast Tradewinds

48. Seasons Seasons are caused by the Earth’s tilt on its axis

50. Terrestrial Biomes