Understanding Ecology: Biosphere, Ecosystems, and Interactions

1. Chapter 3 The Biosphere

2. Chapter 3.1 Concept Map 7 Ecology Biosphere Species Biome Ecosystem Communities Populations Edward Terzian, Jr.

3. Chapter 3.2 Concept Map 13 Detritivore Heterotroph Omnivore Autotroph Herbivore Consumer Producer Carnivore Scavenger Decomposer Food chain Trophic level Ecological pyramid Biomass Food web Edward Terzian, Jr.

4. Chapter 3.3 Concept Map 11 Biogeochemical Cycles H2O cycle Carbon cycle Nitrogen cycle Nitrogen fixation Transpiration Denitrification Evaporation Nutrient Limitation Primary Productivity Limiting Nutrient Algal Bloom Edward Terzian, Jr.

5. 3.1 What is Ecology • Ecology: The study of organisms, their environment, and how they interact with each other. • Includes studying things living and non-living, but is still a large part of Biology. Edward Terzian, Jr.

6. 3.1 What is Ecology • Biosphere: The part of the Earth that sustains life. • All living things on Earth are found in the biosphere. • If you shrank the Earth to the size of an apple, the biosphere would be the thickness of the peel. • Includes from high in the sky to deep in the oceans. Edward Terzian, Jr.

7. 3.1 What is Ecology • Interactions • Species: A group of organisms so similar to each other they can mate and produce offspring • Populations: Group of organisms in the same species that live in the same place and interbreed. • Community: Many groups of different populations (different species as well) that live together. • A collection of interacting populations Edward Terzian, Jr.

8. 3.1 What is Ecology • The interactions between organisms and the abiotic factors around them forms an ecosystem. • Different ecosystems: • Terrestrial • Aquatic • Marine • Freshwater • Biomes: a group of ecosystems that have a climate and dominant communities Edward Terzian, Jr.

9. 3.2 Energy Flow • There are many different ways an organism can obtain the energy that it needs to survive. • First, some organisms can use the sun’s energy OR chemicals in the environment to produce energy for themselves • These organisms are called autotrophs. • Photosynthesis • Chemosynthesis Edward Terzian, Jr.

10. 3.2 Energy Flow • Second, there are organisms that must obtain energy from ingesting (eating) other organisms. • They are called heterotrophs. • Heterotrophs can eat plants, animals, or fungi in order to get energy. Edward Terzian, Jr.

11. 3.2 Heterotrophs • Come in many forms. • Carnivore • Ex. Lions, Dogs • Scavenger- What would the Earth look like if there were no scavengers? • Herbivore • Ex. Cows, Wildebeests • Omnivore • Ex. Humans, Raccoons, Opossums • Decomposers • Ex. Bacteria, Fungi • Detritivores • Ex. Worms, snails, crabs Edward Terzian, Jr.

12. 3.2 Energy Flow • A food chain is a model scientists use to illustrate the flow of energy through an ecosystem. • Ex. Grass » Cow » Human orAlgae » Carp » Heron » Lion • Food chains usually have no more than five steps. •    With each step the amount of energy transferred decreases    Edward Terzian, Jr.

13. 3.2 Energy Flow • In a food chain, each organism represents a different trophic level. • The word trophic is from the Greek tropho and basically means food. Edward Terzian, Jr.

14. 3.2 Energy Flow • The first trophic level usually consists of producers. • Producers are autotrophs that produce their own energy from sunlight or chemicals. • The second level are the herbivores which eat the producers. • The third level are carnivores which eat the herbivores. • The fourth are the carnivore eaters, and so on... Edward Terzian, Jr.

15. 3.2 An Ecological Pyramid Top level - carnivores 3rd level - carnivores Energy, Mass, & Pop. Size Decreasing 2nd level - the herbivores 1st level- the producers/autotrophs Edward Terzian, Jr.

16. 3.2 Energy Flow • An ecological pyramid can describe the flow of energy (as seen on the last slide) or it can describe the amount of biomass that exists at that trophic level. • Biomass is the actual weight of all of the organisms at that trophic level. Edward Terzian, Jr.

17. 3.2 Energy Flow • As you can see on the ecological pyramid, the amount of energy retained decreases as you go up to the top. • With every passing level, 90% of all energy is lost! • Only 10% of the producer’s energy actually makes it into the herbivore’s system! • Only 10% of the herbivore’s energy actually makes it to the first carnivore in the chain! • And so on…    Edward Terzian, Jr.

18. 3.2 Energy Flow • The energy is lost in many different ways. • The food must be digested • Body tissues must be built (muscle, skin, etc.) • Some is given off as waste • A lot as heat Edward Terzian, Jr.

19. 3.2 Energy Flow • In order to survive, a hawk eats 30 pounds of lizards in a month. In that same month in order to survive, those lizards have to eat 300 pounds of crickets. How many pounds of grass do those crickets have to eat in order to survive? Edward Terzian, Jr.

20. 3.2 Energy Flow • There is 9000 pounds of grass in one particular habitat. • How many crickets can this habitat sustain? • How many lizards? • Hawks? Edward Terzian, Jr.

21. 3.2 Energy Flow • A food chain is not that complicated, but in real life, feeding involves more than just a simple food chain. • A food webis more involved, and describes all of the possible feeding situations that can occur in an ecosystem. • See p. 71 Edward Terzian, Jr.

22. 3.2 Food Web Some “webbing” Edward Terzian, Jr.

23. 3.2 Food Web Edward Terzian, Jr.

24. 3.3 Cycles of Matter • Biogeochemical Cycles: When matter is passed from one organism to another or from one part of the biosphere to another. • Water Cycle • Carbon Cycle • Nitrogen Cycle Edward Terzian, Jr.

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28. 3.3 Cycles of Matter • Nutrient Limitation: Limitations being put on the existence of organisms due to availability of nutrients in the ecosystem. • Limiting Nutrient: The actual nutrient in the ecosystem that is scarce or cycles very slowly. • Algal Bloom: When an aquatic ecosystem gets a rapid influx of its limiting nutrient causing a growth explosion of producers. • Primary Productivity: The rate at which organic matter is created by producers. Edward Terzian, Jr.

29. Important Study Tips! • Ecology/Ecosystem/Biosphere • Heterotrophs/Autotrophs • Consumers/Producers • 1st, 2nd, 3rd Order heterotrophs • Carnivores/ Scavengers/Detritivores/Omnivores/Herbivores/Decomposers • Food Chain/Food Web • Water/Carbon/Nitrogen • ENERGY PYRAMIDS! • Nutrient Limitation Edward Terzian, Jr.