Chapter Objectives

1. Explan the improtance of autotrophic organisms with respect to energy flow and nutrient cycling in      ecosystems
2. List and describe the importance of the 4 consumer levels found in ecosystems
3. Explain how gorss primary productivity is allocated by the plants in an ecosystem
4. Explain why productivity declines at each trophic level
5. List factors that can limit ecosystem productivity
6. Distinguish between energy pyramids and biomass pyramids
7. Describe the hydrologic (water) cycle
8. Describe the carbon cycle and explain how it results from the reciprocal processes of photosynthesis and       cellular respiration
9. Describe the nitrogen cycle and explain the importance of nitrogen fixation to living organisms
10. Explain how phosphorus is recycled locally inmost ecosystems
11. Explain why the soil in tropical forests contains lower levels of nutrients than soil in temperate forests
12. Describe how agricultural practices can interfere with nitrogen cycling
13. Describe how deforestation can affect nutrient cycling within an ecosystem
14. Describe how the carbon cycle differs in terrestrial and aquatic ecosystems
15. Explain how "cultural eutrophication" can alter freshwater ecosystems
16. Explain why toxic compouns usully hae the greatest effect on top-level carnivores
17. Describe how increased atomospheric concentrations of carbon dioxide could affect the earth
18. Describe how human interference might alter the biosphere
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19. List the major threats to biodiversity and give an example of each
20. Describe the importance of biodiversity
21. Describe the 3 basic concepts upon which the field of biodiversity is based
22. Describe the goal of conservation biology
23. Describe ho biodiversity is distributed
24. Define the term : "biodiversity hot spot"
25. Describe the problems presented to conservation by migratory species
26. Describe how the biodiversity cirsis extends throughout the hierarchy of biological organization
27. Describe how habitat fragmentation affects population dynamics
28. Define "source habitat" and "sink habitat" and how these concepts relate to conservation habitats
29. Describe how population viability analysis and estimates of minimum viability size and effective        population size are used to evaluate the chances of a species persisting or becoming extince
30. Give examples of how predictive models are being used in conservation efforts
31. Describe the conflicting demands that arise in conservation managment plans
32. Describe how edges and corridors influence landscape biodiversity
33. Discuss why nature reserves are important to preserving biodiversity and why conservation efforts will        involve working in landscapes dominated by humans
34. Describe why restoring degraded areas is an important part of conservation bioogy and how        bioremediation and augmentation play a role in restoration efforts
35. Describe how sustainable development goals are reorienting ecological research and will require        changes in some human values

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Chapter Terms:

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Chapter Outline Framework

A. Trophic Relationships in Ecosystems

1. Trophic relationships determine an ecosystem's routes of energy flow and chemical cycling
2. Primary producers include plants, algae, and may species of bacteria
3. Many primary and higher-order consumers are opportunistic feeders
4. Decomposition interconnects all trophic levels

B. Energy Flow in Ecosystems

1. An ecosystem's energy budget depends on primary productivity
2. As energy flows through an ecosystem, much is lost at each trophic level

C. Cycling of Chemical Elements in Ecosystems

1. Biological and geological processes move nutrients among organic and inorganic compartments
2. Decomposition rates largely determine nutrient cycling rates
3. Field experiments reveal how vegetation regulates chemical cycling

D. Human Impacts on Ecosystems

1. The human population disrupts chemical cycles throughout the biosphere
2. Toxins can become concentrated in successive trophic levels of food webs
3. Human activities are causing fundamental chantes in the composition of the atmosphere
4. The exploding human population is alterint habitats and reducing biodiversity worldwide

E. The Biodiversity Crisis: An Overview

1. Numerous examples indicate that estimates of extinction rates are on track
2. The major threats to biodiversity are habitat destruction, over-exploitaiton, and competition by exotic species
3. Biodiversity is vital to human welfare
4. Change in ecological and evolutionary time is the focus of consevation biology

F. The Geographic Distribution of Biodiversity

1. Gradual variation in biodiversity correlates with geographical gradients
2. Biodiversity hot spots have high concentrations of endemic species
3. Migratory species present special problems in conservation

G. Conservation at the Pouplation and Species Level

1. Sustaining genetic diversity and the environmental area for evolution is an ultimate goal
2. The dynamics of subdivided populations apply to problems caused by habitat fragmentation
3. Population viability analyses examine the chantes of a species persisting or becoming extincet in the habitats available to it
4. Analyzing the viability of selected species may help sustain other species
5. Conservign species involves weighing conflicting demands

H. Conservation at the Community, Ecosystem, and Landscape Levels

1. Edges and corridors can strongly influence landscape biodiversity
2. Nature reserves must ge functional parts of landscapes
3. Restoring degraded areas is an increasingly important conservation effort
4. Sustaining development goals are reorienting ecological research and will require changing some      human values

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