1. Ecosystems and Communities
Chapter 4 & 5 Notes

2. Every organism affects its environment, and in turn is affected by its environment.  Ecosystems are affected by two kinds of factors

3. The Nonliving Environment
Abiotic factors- ___________________________________________________
Ex. ______________ 3 3

4. The Living Environment
Biotic factors- ___________
______________________________________________
All organisms depend on others directly or indirectly for food, shelter, reproduction, or protection. 4 4

5. Biotic or Abiotic? Predators ________________
Hot weather ________________
Acid rain ________________
Wood from trees ______________
Your parents ________________
The river flow ________________
The leeches found in the river ________________

6. Weather for Sugar Land, TX
The Role of Climate
Weather for Sugar Land, TX
Sunday Sept. 16, 2007
Weather: ____________________________________________________________________________
Temperature
Wind
Precipitation
Humidity
Specific weather patterns

7. The Role of Climate
Climate: it is the average conditions in a region over several decades; affects the soil, and in turn the vegetation, and in turn other organisms in an area. It is described by:
_______________________

8. The Role of Climate
____________________________________________________________________

9. The Role of Climate
Polar: º N or S (within the Arctic and Antarctic circles)
Temperate: from the lines of Tropic of Cancer and Capricorn to 66.5 º N or S, respectively
Tropical: between the Tropic of Cancer and Tropic of Capricorn
Polar (blue)
Temperate (green)
Tropical (red)

10. Other determinates of weather and climate:
Coastal or central to the continent?
______________________________________________________________________________________________________

11. Other determinates of weather and climate:
Upwelling: ___________________________
________________________________________________________________________
Diagram illustrating the principle of equatorial upwelling. Winds along the equator (dotted line) create currents, which are then diverted north and south by the Coriolis force. The cold, deep waters from below rise to the surface to replace these diverted waters, causing upwelling.

12. Greenhouse Effect: the natural situation in which heat is retained by the greenhouse gases (CO2, methane, water vapor, etc.) is called the greenhouse effect. If these gases were not present, the Earth would be 30º C cooler and unlivable

13. Biomes
-a collection of ecosystems with the same climate and dominant communities; 2 main areas of biomes
Aquatic- in water
Terrestrial- on land

14. Aquatic Photic zone- _______________________ (shallow water)
Aphotic zone- ______________________ (deep water)
Estuary- ______________________
________________ (end of a river)
Tidal zone- ________
__________________
Tidal Zone
Photic Zone
Aphotic Zone

15. Community Interactions
Habitat- ___________________________
Niche- ____________________________
__________________________________
Competition- _______________________
Interspecific competition: between members of different species
Intraspecific competition: between members of the same species

16. Predation __________________________________
__________________________________ ex: lion eats a zebra

17. Community Interactions
Symbiosis- ________________________
__________________________________

18. Community Interactions
Mutualism- _______________________
________________________________ (ant live on an acacia tree, ant protects tree from harmful plants, tree gives ant a home)
Clownfish live within sea anemones, which normally sting other fish. The fish gets protection, and the anemone benefits because the clownfish keep it clean of bacteria.

19. Community Interactions
Parasitism- ________________________
__________________________________ (fleas or ticks on a dog; flea gets a home, sucks the dog’s blood and is bothered by it)
Leech sucks the blood of a human

20. Community Interactions
Commensalism- ____________________
__________________________________ (moss growing on trees)
Epiphytes are plants that grow on other plants without harming them. They never set root in the ground!

21. When grazing cows walk around, they disturb the ground, which stirs up insects. Birds follow the cows around and eat these insects.

22. Cleaner shrimp living in the ocean eat ectoparasites off of larger fish. The cleaner fish get a meal and the larger fish get rid of a parasite.

23. A botfly lays maggots inside a man's head, providing shelter and nutrition for its young.

24. Factors Affecting Populations
Three things affect population size:
________________________________
________________________________________________________________________________________________

25. Types of Growth
Exponential Growth- if a population has abundant space and food, no disease or predators; it will grow at an exponential rate. It is a J-shaped curve resembling y = ax2 + b

26. Types of Growth
Logistic Growth- population growth slows then stops (stays stable) after a period of exponential growth once resources become less available. The number at which the environment can support this population is known as the carrying capacity.

27. Limiting factors factor that causes a population to decrease in size
Two types…

28. Limiting Factors Density dependent- _________________________
___________________________________________________________________________________________________________________________
Notice the pattern of population size with predator/prey relationship of hares and lynxes

29. Limiting Factors Density independent- ________________
______________________________________________________________________________________________________
Unusual weather
natural disasters
seasonal cycles
certain human activities

30. Ecological Succession
After such disasters, a community can start anew by a process called ecological succession (series of predictable changes that occurs in a community over time); there are two types

31. Succession Primary succession- _________________
______________________________________________________________________________________________________

32. Succession Secondary succession- _______________
______________________________________________________________________________________________________