Chapter 7: The Use and Restoration of Ecosystems Flashcards
Ecosystem Capital
ecosystems and species and the goods and services they generate
Regulating services
benefits from regulation of ecosystem processes
Cultural services
nonmaterial benefits from ecosystem
Supporting services
maintain themselves
Natural resources
natural ecosystems and their biota
Benefits of conversion
local, short term, and specific
What percent of land is used for crop and livestock
50%
How much of the world’s forests have been lost?
Half
The ability of ecosystems to sustain future generations…
Can no longer be taken for granted
What will be needed for increasing population?
More food, wood, space, fisheries, and water
Why are ecosystems worldwide declining?
Human activities
What is being lost due to declining ecosystems?
Species and goods and services for humans
Natural goods
provisions (food, wood, fuel, water)
What are killing reefs?
breakage, pollution, heat, invasive species
The concept of ecosystem capital…
Involves both ecological and economic value of ecosystem
A natural area is protected only when…
Society values its services more than the direct human use of the resource
Because services are underappreciated…
Ecosystems are usually damaged for short term profit
Conservation
manages or regulates use so it doesn’t exceed the capacity of the species or system to renew itself
What makes something a renewable resource?
- can replenish itself
2. it’s sustainable
Preservation
ensure species and ecosystem continuity regardless of their potential utility
Old-growth (virgin) forest
never been cut
Consumptive use
people harvest natural resources for food, shelter, tools, fuel, clothing
When people are using consumptively…
Resources are used for people’s own needs
Bush meat
wild game in Africa that provides protein
Productive use
the exploitation of ecosystem resources for economic gain
When people are using productively
products are harvested and sold
What is an important source of revenue and employment?
Productive use
Four types of tenure
- Private ownership
- Communal ownership
- State ownership
- Open access
Open access
resources can be used by anyone
The optimal population for harvesting the MYS is…
halfway to the carrying capacity
Maximum Systainable Yield (MSY)
the highest rate of use the system can match with its own rate of replacement or maintenance
MSY is just before the point at which use begins to…
destroy the system’s regenerative capacity
Carrying capacity
the maximum population the ecosystem can sustainably support
A population below carrying capacity…
grows
A population approaching carrying capacity…
competition between individyals reduces recruitment
In a population near or at carrying capacity…
- MSY cannot be obtained
2. the optimal population for harvesting the MSY is halfway to K
The optimal population for harvesting the MSY is…
halfway to the carrying capacity
Why is using MSY complicated?
- It has to be recalculated yearly
- weather, acorn crops, human impacts etc.
- Replacement of harvested individuals varies
What is MSY used to do?
To set a fixed quota
Whay is MSY in fisheries?
Total allowable catch (TAC)
Precautionary principle
Where there is uncertainty, managers must favor resource protection
Exploitation limits are set…
below MSY
A common-pool resource (commons)
owned by many people or by no one (open access)
Exploitation of the commons
causes serious problems
Tragedy of the commons
ruin of the resource
Sustainability
maintaining common-pool resources to yield benefits for present and future users
Lesson of Tragedy of the Commons
No management of a common resource and widespread pursuit of personal interests leads to tragedy or loss for all
Private ownership
can reduce the tragedy of the commons
How does private ownership reduce the tragedy of the commons?
it restricts access to a renewable natural resource
Regulating access to a commons allows for
- Protection for sustained benefits
- Fairness in access
- Mutual consent of the regulated
- Best if locally controlled by those who benefit most
Lesson of the Turtle Island Commons
Sustainable management of a common pool resource must involve the local people and allow them to benefit from the resource while protecting it at the same time
Restoration ecology
restores damaged ecosystems
What is the intend of restoration ecology?
To repair the damage to ecosystems so that the normal integrity, resilience, and productivity return
Because of the complexity of ecosystems…
restoration is often difficult
Restoration ecology is costly but essential
Has become a worldwide $70 billion industry
The greater the damage…
the more complex and challenging the restoration will be
Deforestation
The removal of forest and replacement by another use
Silviculture
The practice of forest management
Clear-cutting
Removes an entire stand at one time and creates a fragmented habitat
Selective cutting
Removes some mature trees
Shelter-wood cutting
Mature trees are cut in groups, leaving some trees for seeds and shelter
Sustained yield
production of wood is the primary goal
Sustainable forest management
managing forests as ecosystems
Comprehensive Everglades Restoration Plan (CERP)
d
Magnuson-Stevens Fishery Conservation and Management Reauthorization Act
- Set catch limits below MSY
- Use precautionary principles
- End overfishing in two years
- Limit bycatch
- Accountability measures
Bycatch
non target species
The world fish catch may appear stable, but…
many species and areas are overfished
Three species declined from overfishing
Cod, haddock, flounder (groundfish)
rized fish species decline due to…
poor management
What gives fish little chance of escaping?
too many boats rigged with technology
Catch shares
a system that gives fishers transferrable “property rights” in the fishery
Marine protected areas (MPA)
coasts and open oceans closed to all commercial fishing and mineral mining
Most MPA have been…
successful and are vital for recovery
What are the most direct path to resoration?
Reserves
Who still whales?
Japan, Iceland, and Norway
What does whale watching provide?
Aesthetic, entertainment, and scientific value (conservatic value)
One of the most diverse and productive ecosystems
Coral reefs
Coral bleaching
corals expel their algae and die when water temperature increases
Ocean acidification
from excess CO2 (drop in pH, negatively affect chemicals in water
What do people use cyanide and dynamite to do?
flush fish to catch for food and the pet trade
Increased water temperatures…
disrupt symbiotic relationships
What do mangroves do?
- protect coasts from storm damage and erosion
2. provide nurseries for marine fish
What are mangroves threatened by?
development, logging, aquaculture (lost to shrimp farms)
How much of the world’s mangroves have been lost?
half
What causes the greatest negative impact to global biodiversity
Farming and fisheries
Wilderness
land given the most protection (preservation, level 1)
National parks
84 million acres
National wildlife refuges
96 million acres
Level 2
National parks and national wildlife refuges
What do national parks and national wildlife refuges do?
- protect species
- provide public access for recreation
- two goals can conflict with each other
Level 3
National forests (740 million acres, 2/3rd managed for commercial timber harvest)
Multipe use
the Forest Service’s old management principle intended to balance many uses (ephasized extraction/product)
New forestry
management that emphasizes protection of ecological health and forest diversity over max harvest of logs
Forest growth now exceeds harvest, indicating that…
forests are being managed sustainably
President Clinton’s Forest Service chief embraced the..
ecosystem management paradigm
Roadless Area Conservaion Rule
banned new logging roads, protecting 58 million acres
Private land trust
A nonprofit organization accepts gifts of land, protects land from development
Easements
land owners give up development, but not ownership, rights
What do rivate conservation efforts rely on?
Land trusts
Who are working to manage natural sites as part of larger ecosystems
Gov. agencies, environmental groups, private citizens
