Principles of Ecology

1. Principles of Ecology Chapter 2

2. Do Now • Please complete the handout at your desk • You have 10 minutes

3. Organisms and Their Environment • Ecology—the scientific study of organisms and their interactions with the environment • Studies relationships of living and nonliving parts • What kinds of questions might an ecologist ask?

4. Example: Cow • Ecologist would study: • What it eats • Where it lives • What other organisms it interacts with • Patterns of dispersion • What eats it • Disease • Impact on environment • And more

5. The Biosphere • Biosphere—the portion of Earth that supports life

6. Abiotic Factors • The non-living components of an environment • Examples: • Rocks • Air • Temperature • Light • Moisture

7. Biotic Factors • The living parts of an environment, including the organisms themselves • Examples: • People • Plants • Animals • Fungi • Bacteria

8. Levels of Organization • Organism • Population—a group of organisms of the same species within the same geographic location • Biological Community—a group of interacting populations that occupy the same area at the same time • Ecosystem—a biological community and all of its abiotic factors • Biome—a group of ecosystems of the same climate and types of communities • Biosphere

9. Habitats and Niches • A habitat is a place where an organism lives • An ecological niche is the role and position of an organism within its environment

10. A Word about Niches • Organisms or species cannot occupy the same exact ecological niche at the same time • Why??? • https://www.youtube.com/watch?v=xIVixvcR4Jc

11. Symbiosis • Sym= Together • Bio= Living • Symbiosis is close association between two or more organisms • There are a few key types of symbiotic relationships

12. Parasitism • A type of symbiotic relationship where one organism clearly benefits because it is living at the expense of another (+/-)

13. Mutualism • Both organisms in the relationship benefit • (+/+) • https://www.youtube.com/watch?v=dJRJCO59bf4

14. Commensalism • One organism benefits and the other is not affected (+/0) • Example: Sea anemone and clownfish

15. Energy in Ecosystems • Autotrophs are organisms that use energy from the sun to manufacture their own nutrients • Literally means “self feeder” • Heterotrophs are organisms that must feed on other organisms and cannot make their own food

16. Types of Heterotrophs • Herbivore—eats plants • Carnivore—meat eaters • Omnivore—eats all • Detritivore—eats dead organic material

17. Food Chains and Webs • A food chain is a simple model that shows how energy flows through an ecosystem • GrassCowHuman • Food Webs are models representing interconnected food chains in which energy flows through a group of organisms • Trophic Levels are steps in the food web or chain • https://www.youtube.com/watch?v=Cd1M9xD482s

18. Trophic Levels • Levels of energy passage

19. Trophic Levels • Plants= producers • Animals who cannot make their food are primary, secondary, tertiary, and quaternary consumers • Then there are the detritivores

20. Figure 42.4 Sun Key Chemical cycling Heat Energy flow Primary producers Primary consumers Detritus Microorganisms and other detritivores Secondary and tertiary consumers

21. Energy Pyramid Tertiary consumers 10 J Secondary consumers 100 J Primary consumers 1,000 J Primary producers 10,000 J 1,000,000 J of sunlight

22. Figure 42.11 Biomass Pyramids Dry mass (g/m2) Trophic level Tertiary consumers 1.5 Secondary consumers 11 Primary consumers 37 809 Primary producers (a) Most ecosystems (data from a Florida bog) Dry mass (g/m2) Trophic level Primary consumers (zooplankton) 21 Primary producers (phytoplankton) 4 (b) Some aquatic ecosystems (data from the English Channel)

23. Pyramid of Numbers

24. Biogeochemical Cycles • Nutrient cycles in ecosystems involve biotic and abiotic components and are often called biogeochemical cycles • Common cycles include • Carbon • Oxygen • Sulfur • Nitrogen • Phosphorus • Water

25. The Water Cycle • Water is essential to all organisms • Liquid water is the primary physical phase in which water is used • The oceans contain 97% of the biosphere’s water; 2% is in glaciers and polar ice caps, and 1% is in lakes, rivers, and groundwater • Water moves by the processes of evaporation, transpiration, condensation, precipitation, and movement through surface and groundwater

27. The Nitrogen Cycle • Nitrogen is a component of amino acids, proteins, and nucleic acids • The main reservoir of nitrogen is the atmosphere (N2), though this nitrogen must be converted to NH4+ or NO3− for uptake by plants, via nitrogen fixation by bacteria • Nitrogen fixation is conversion of unusable forms of nitrogen into forms that plants and animals can use • Denitrificationis when fixed nitrogen is converted back into atmospheric nitrogen

28. Figure 42.13c N2 in atmosphere Reactive N gases Industrial fixation Denitrification N fertilizers Fixation Runoff Dissolved organic N Terrestrial cycling NO3− N2 NO3− NH4 Aquatic cycling Denitri- fication Decomposition and sedimentation Assimilation Decom- position NO3− Fixation in root nodules Uptake of amino acids Ammoni- fication Nitrification NH4 The nitrogen cycle

29. Chapter 2 Assessment • Go to page 53 • Respond to the “Constructed Response” questions • #9, 10, 23, 34, 35

30. Classwork • Take a look at each of the cycles starting on page 46 of your textbook • Water • Carbon/Oxygen • Nitrogen • Phosphorus • Draw a simplified diagram of each of the four cycles and annotate it for your notes

31. Communities, Biomes, and Ecosystems April 25, 2014

32. Do Now • Take 8 minutes to look over your notes for the quiz • HINT: It might be helpful to know how to make a cladogram • If you talk during this time, you lose this time, so use it wisely 

33. Community Ecology • What is YOUR community?

34. Communities • A community is a group of interacting populations that occupy the same area at the same time • It is not restricted to a single species or population, its all of the living things in the area

35. What do you think? • How can communities vary? • Could an organism survive in just any community? How does this tie into ecological niche?

36. Limiting Factors • Limiting factors are biotic or abiotic factors in an ecosystem or community that restrict the numbers, reproduction, or distribution of organisms • Can you think of any??

37. Sample Limiting Factors • Sunlight • Temperature • Water • Nutrients • Fire • Soil Chemistry • Available Space • Other living things Abiotic Factors Biotic Factors

38. Tolerance • Every organism has an upper and lower limit for each limiting factor • The ability of an organism to survive when it is subjected to biotic or abiotic factors is called tolerance

39. Tolerance

40. What happens when…? • A fire burns down a forest? • A volcano erupts and flows over fertile land? • Humans clear forests for lumber?

41. Ecological Succession • Ecological succession is the change in an ecosystem that happens when one community replaces another as a result of changing abiotic and biotic factors • Primary succession occurs in areas in which there is no layer of topsoil • Secondary succession is the orderly and predictable change that occurs after a community or organisms have been removed but the soil has remained intact

42. Climax Communities • Climax communities occur when there is little change in the composition of a species

43. Weather and Climate • Weather is the condition of the atmosphere at a specific place and time • Latitude is the distance at any point of the Earth north or south from the equator • Climate is the average weather conditions in an area, including temperature and precipitation

44. Biomes: Tundra • Freezing temperatures • Treeless • Covered by layer of permafrost • Contains some animals and shallow-rooted plants

45. Boreal Forest • South of the tundra • Evergreens • Slightly warmer than tundra with longer summers • No permafrost layer • Used to be called taiga

46. Temperate Forest • Cover southeast Canada, eastern US, most of Europe, and parts of Asia and Australia • Composed of mainly deciduous (broad-leafed) forest • Has all four seasons

47. Temperate Woodland and Shrubland • Open woodlands and mixed shrub communities • Less rainfall than temperate forest • Occurs in Mediterranean, west coasts of North and South America, South Africa, and Australia

48. Temperate Grassland • Fertile soils • Thick cover of grasses • Found at middle latitudes • No large trees • Infrequent rainfall

49. Desert • Exists on every continent except Europe • Any area in which the annual rate of evaporation exceeds the annual rate of precipitation • Sometimes resemble traditional desert, but sometimes do not

50. Tropical Savanna • Grasses and scattered trees • Less rainfall than other tropical areas • Mostly in Africa, Australia, and South America