1. Ecosystems: What Are They and How Do They Work? G. Tyler Miller’s Living in the Environment 14 th Edition Chapter 4 G. Tyler Miller’s Living in the Environment 14 th Edition Chapter 4

2. Key Concepts  Basic ecological principles  Major components of ecosystems  Matter cycles and energy flow  Ecosystem studies  Principles of Sustainability

3. The Nature of Ecology  Ecosystem organization  Organisms  Populations  Communities  Ecosystems  Biosphere Fig. 4-2 p. 57

4. The Earth’s Life-Support Systems  Troposphere  Stratosphere  Hydrosphere  Lithosphere  Biosphere Fig. 4-7 p. 60

5. Natural Capital: Sustaining Life of Earth  One-way flow of energy from Sun  Cycling of Crucial Elements  Gravity Fig. 4-8 p.60

6. Solar Capital: Flow of Energy to and from the Earth Fig. 4-9 p. 61

7. Natural Capital: Major Biomes  Biomes Fig. 4-10 p. 62  Role of climate  Aquatic life zones

8. Climate and Major Biomes

9. Ecotone: transitional region between different ecosystems Shares many of the species and characteristics of both ecosystems May also include unique conditions that support distinctive plant and animal species

10. Ecotone: transitional region between different ecosystems Shares many of the species and characteristics of both ecosystems May also include unique conditions that support distinctive plant and animal species

11. Ecosystem Factors  Abiotic factors  Biotic factors  Range of tolerance  Limiting factors Fig. 4-13 p. 64

12. Application of the Law of Limiting Factors Compare the “tolerance” differences for a trout and a catfish using water: –temperature (cold or warm). –oxygen concentration (high or low). –salinity (high or low).

13. Law of Limiting Factors

14. Components of Ecosystems  Producers (autotrophs)  Photosynthesis  Consumers (heterotrophs)  Aerobic respiration  Decomposers Fig. 4-17 p. 67  Abiotic chemicals

15. Autotrophs = Producers = Self feeders

16. Consumers = Heterotrophs Primary consumers = herbivores = rabbits: eat plant material Secondary consumers = carnivores = predators = coyotes: prey are herbivores and other animals Parasites = predator = either plant or animal: prey are plants or animals Detritus feeders and decomposers = bacteria and fungi: prey are plants or animals

17. Trophic Categories

18. Trophic Relationships among Producers and Consumers

19. Biodiversity  Genetic diversity  Species diversity  Ecological diversity  Functional diversity

20. Connections: Energy Flow in Ecosystems  Trophic Levels  Food webs  Food chains

21. Food Assimilation in Consumers

22. Trophic Levels  Primary consumer (herbivore)  Secondary consumer (carnivore)  Tertiary consumer  Omnivore  Detritivores and scavengers  Decomposers

23. Connections: Food Chains and Energy Flow in Ecosystems Fig. 4-18 p. 68

24. Energy Flow through Trophic Levels

25. Ecological Pyramids  Pyramid of energy flow  Ecological efficiency  Pyramid of biomass  Pyramid of numbers Fig. 4-21 p. 70

26. Primary Productivity of Ecosystems  Gross primary productivity (GPP)  Net primary productivity (NPP) Fig. 4-24 p. 72

27. Soils  Origins  Importance  Maturity and Horizons  Variations with Climate and Biomes  Variations in Texture and Porosity  Origins  Importance  Maturity and Horizons  Variations with Climate and Biomes  Variations in Texture and Porosity

28. Soil Profiles in Different Biomes Fig. 4-27, p. 75

29. Connections: Matter Cycling in Ecosystems  Biogeochemical cycles  Hydrologic cycle (H 2 O)  Carbon cycle  Phosphorus cycle  Nitrogen cycle  Sulfur cycle

30. Hydrologic (Water) Cycle Fig. 4-28 p. 76

31. The Carbon Cycle (Marine) Fig. 4-29, p. 78

32. The Carbon Cycle (Terrestrial) Fig. 4-29, p. 78

33. The Nitrogen Cycle Fig. 4-31 p. 80

34. The Phosphorus Cycle Fig. 4-33 p. 82

35. The Sulfur Cycle Fig. 4-34 p. 83

36. How Do Ecologists Learn About Ecosystems?  Field research  Remote sensing  Geographic information systems (GIS)  Laboratory research  Systems analysis

37. Geographic Information System (GIS) Fig. 4-35 p. 84

38. Systems Analysis Fig. 4-36 p. 85