Chapter 3 The Biosphere

1. Chapter 3 The Biosphere Section 1 What is Ecology? (pp. 63 – 65) Section 2 Energy Flow (pp. 67 – 73) Section 3 Cycles of Matter (pp. 74 – 80) Created by C. Ippolito November 2004

2. What is Ecology? What different levels of organization do ecologists study? What methods are used to study ecology? Created by C. Ippolito November 2004

3. Interactions and Interdependence • Ecology – studies the interactions of organisms and their surroundings. • eco – Greek word for house • Logy – Greek word for study of • Ernst Haeckel saw the living world as a household with each organism having a role to play • Biosphere – everywhere on Earth that life can exist Created by C. Ippolito November 2004

4. Levels Within Levels • An ecosystem is a collection of all the organisms that live in a particular place, together with their nonliving, or physical, environment. Within an ecosystem, there are several levels of organization. Your school and its grounds are similar to an ecosystem. Created by C. Ippolito November 2004 Go to Section:

5. 1. What living things are found in and around your school? • 2. What nonliving things are found in your school? • 3. Into what large groups are the students in your school divided? • 4. Into what smaller groups are these large groups divided? • 5. Are these groups ever divided into even smaller groups? If so, what are these groups? Created by C. Ippolito November 2004 Go to Section:

6. Levels of Organization • Ecologists can study relationships from the level of a single cell to the whole biosphere • Species – group that can breed and produce fertile offspring • Population – group of same species in the same area • Community – different populations living together in a specific area • Ecosystem – all organisms and their nonliving, or physical surroundings • Biome – group of ecosystems with same climate and dominant communities Created by C. Ippolito November 2004

7. Ecological Methods • Modern ecological research involves THREE (3) basic approaches: • Observing • What species live here? How many are here? • Experimenting • Use artificial environment in lab (aquaria, terrariums, etc.) • Modeling • Mathematical formulas based on observations to predict long range effects Created by C. Ippolito November 2004

8. Energy Flow Where does the energy for life processes come from? How does energy flow through living systems? How efficient is the transfer of energy among organisms in an ecosystem? Created by C. Ippolito November 2004

9. Producers • Sunlight is the main energy source. • Less than 1% is used by organisms • Autotrophs (producers) – use energy to form food • Photosynthesis – use energy from sunlight to form complex organic chemicals from simple inorganic chemicals • Chemosynthesis – use chemical energy from hydrogen sulfide or heat vents to form complex organic chemicals from simple inorganic chemicals Created by C. Ippolito November 2004

10. Consumers • Heterotrophs (consumers) - Cannot harness energy directly; acquire it from other organisms. • Herbivores – obtain energy by eating plants • Carnivores - obtain energy by eating animals • Omnivores - obtain energy by eating both • Detritivores - obtain energy by eating plant and animal remains (detritus) • Decomposers – change organic matter back into inorganic matter Created by C. Ippolito November 2004

11. Feeding Relationships • Energy flows in one direction in an ecosystem • Sun  autotrophs heterotrophs • Food Chain – series of steps in which organisms transfer energy by eating and being eaten Created by C. Ippolito November 2004

12. Food Web • A complex interaction of feeding relationships • Trophic Level • step in a food chain or food web Created by C. Ippolito November 2004

13. Regents Example of Food Web Created by C. Ippolito November 2004

14. Ecological Pyramids • Diagrams used to show relative amounts of energy or matter at each trophic level in a food chain or food web • Energy Pyramid – only 10% of energy transfers from one level to the next! • Biomass Pyramid – total amount of living tissue at each level • Numbers Pyramid – number of individuals at each level Created by C. Ippolito November 2004

15. Energy Pyramids Created by C. Ippolito November 2004

16. Biomass Pyramid Created by C. Ippolito November 2004

17. Numbers Pyramid Created by C. Ippolito November 2004

18. Regents Pyramids Created by C. Ippolito November 2004

19. Cycles of Matter How does matter move among the living and non living parts of an ecosystem? How are nutrients important in living systems? Created by C. Ippolito November 2004

20. Recycling in the Biosphere • Unlike the one-way flow of energy, matter is recycled within and between ecosystems. • Biogeochemical Cycles – trace how biological, geological, and chemical materials move through an ecosystem. • Water Cycle • Nutrient Cycles • Carbon • Nitrogen • Phosphorus Cycle Created by C. Ippolito November 2004

21. Water Cycle Created by C. Ippolito November 2004

22. Carbon Cycle Created by C. Ippolito November 2004

23. Nitrogen Cycle Created by C. Ippolito November 2004

24. Nutrient Limitation • Primary Productivity – rate at which producers form organic matter • Limiting Nutrient – single nutrient or factor that is scarce or recycles very slowly • Algal Bloom – runoff causes large increase of a normally limited nutrient causing a burst of growth in one segment of system Created by C. Ippolito November 2004