Chapter Objectives: Chapters 54 & 55 Ecosystems and Conservation
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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ecosystem
trophic structure
trophic level
primary producers
primary
consumers
sedondary
consumers
tertiary
consumers
detritivores
detritus
denitrification
food chain
food web
production
consumption
decomposition
primary
productivity
gross primary
productivity
net primary
productivity
secondary
productivity
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biomass
standing crop
limiting nutrient
ecological
efficiency
productivity
pyramid
biomass pyramid
turnover time
pyramid of
numbers
biogeochemical
cycle
nitrogen fixation
ammonification
long-term
ecological
research (LTER)
biological
magnification
greenhouse effect
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conservation biology
biodiversity
biodiversity crisis
source habitat
sink habitat
biodiverrsity hot spot
endemic species
endangered species
threatened species
metapopulation
propulation viability
analysis
minimum viable
population size
minimum dynamic area
effective population
size
landscape ecology
movementcorridor
zoned reserve
systems restoration
ecology
bioremediation
sustainable
development
Sustainable Biosphere
Initiative
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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