1. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh Edition Solomon Berg Martin Chapter 53 Ecosystems and the Biosphere

2. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Energy flow through an ecosystem Linear Sun to producer to consumer to decomposer Trophic relationship may be expressed as food chains or as food webs

3. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Energy flow through an ecosystem

4. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Ecological pyramids Express the progressive reduction in numbers of organisms, biomass, and energy found in successive trophic levels

5. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Pyramids of biomass

6. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Gross primary productivity (GPP) Rate at which photosynthesis captures energy Net primary productivity (NPP) Energy that remains after plants and other producers carry out cellular respiration

7. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere NPP for selected ecosystems

8. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Carbon cycle Carbon dioxide is the most important gas Carbon enters plants, etc., as CO 2 Cellular respiration, combustion, and erosion of limestone return CO 2 to the environment

9. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Carbon cycle

10. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Nitrogen cycle Five steps –Nitrogen fixation –Nitrification –Assimilation –Ammonification –Denitrification

11. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Nitrogen cycle

12. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Phosphorus cycle Phosphorus erodes from rock as inorganic phosphate Animals obtain it from their diet

13. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Phosphorus cycle

14. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Hydrologic cycle Renews the supply of water Involves an exchange of water between the land, ocean, atmosphere, and organisms Water enters the atmosphere by evaporation and transpiration Water leaves the atmosphere as precipitation

15. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Hydrologic cycle

16. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Bottom-up processes Availability of resources such as nutrient minerals controls the number of producers, which controls the number of herbivores, etc. Top-down processes An increase in top predators cascades down the food web

17. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Sunlight primary source of energy Combination of Earth’s spherical shape and its axis tilt concentrate solar energy at the equator Inclination of Earth’s axis primarily determines the seasons

18. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Seasonal changes in temperature

19. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Visible light and infrared radiation warm the surface and lower part of the atmosphere Atmospheric heat produces air movement, which moderates the climate

20. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Atmospheric circulation

21. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Major surface ocean currents

22. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Coriolis effect Tendency of moving air or water to be deflected –Right in the Northern Hemisphere –Left in the Southern Hemisphere

23. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Regional precipitation differences Influenced by latitude, elevation, topography, vegetation, distance from large bodies of water, and location Precipitation greatest where warm air passes over the ocean and then cools

24. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Rain shadow

25. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 53 Ecosystems and the Biosphere Effect of fire on certain ecosystems Fire frees the nutrient minerals locked in organic matter, removes plant cover, and increases erosion Many ecosystems, such as savanna, chaparral, grasslands, and certain forests, contain fire- adapted organisms