Transcript Forest Management

Question of the Day
• Which of the following is a commercially used method
for harvesting trees and is most likely to lead to a
fragmented landscape with serious impacts on
biodiversity?
- Selective cutting
- Clear-cutting
- Shelter-wood cutting
- Slash and burn clearing
- Gleaning
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FOREST MANAGEMENT
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Resources are vital to us
• We need to carefully manage the limited resources
we take from the natural world
• Resource management = the practice of harvesting
potentially renewable resources in ways that do not
deplete them
- Resource managers are influenced by political,
economic, and social factors
- A key question is whether to focus on the resource
of interest or to look more broadly at the entire
environmental system
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Natural resources are vital to us
• We need resources
- Soils: agriculture, natural
communities
- Water: drinking, agriculture,
wildlife
- Wildlife and fisheries: game,
nongame, and marine species
- Rangeland: livestock
- Minerals: mined
nonrenewable resources
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Maximum sustainable yield
• Maximum sustainable yield = aims to achieve the
maximum amount of resource extraction
- Without depleting the resource from one harvest to the
next
• Populations grow most rapidly at an intermediate size
- Population size is about half its carrying capacity
- Managed populations are well below what they would
naturally be
Reducing populations so
drastically affects other
species and can change the
entire ecosystem
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Ecosystem-based management
• Ecosystem-based management = managing the
harvesting of resources to minimize impact on the
ecosystems and ecological processes
- Carefully managing ecologically important areas
- Considering patterns at the landscape level
- Protecting some forested areas
- Ecosystems are complex, and our understanding of
how they operate is limited
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Adaptive management evolves and improves
• Adaptive management = systematically testing different
management approaches and aiming to improve methods
- Monitoring results and adjusting methods as needed
- A fusion of science and management
- Time-consuming and complicated
• The 1994 Northwest Forest Plan resolved disputes between
loggers and preservationists over the remaining old-growth
temperate rainforests in the continental U.S.
- Allowed limited logging
- Protected species and ecosystems
- Science-guided management in Oregon, Washington, and
California
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Forest Management
• Forests cover over 30% of
Earth’s land surface
- Provide habitat, maintain soil,
air, and water quality, and play
key roles in biogeochemical
cycles
- Provide wood for fuel,
construction, paper production
• Foresters, professionals who
manage forests through the
practice of forestry, must balance
ecosystem services with demand
for wood products
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Ecological value of forests
• One of the richest ecosystems for biodiversity
- Structural complexity houses great biodiversity
• A forest provides many ecosystem services
- Stabilizes soil and prevents erosion
- Slows runoff, lessens flooding, purifies water
- Stores carbon, releases oxygen, moderates climate
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Natural Capital
Forests
Ecological
Services
Support energy flow
and chemical cycling
Reduce soil erosion
Absorb and release
water
Economic
Services
Fuelwood
Lumber
Pulp to make paper
Mining
Purify water and air
Livestock grazing
Influence local and
regional climate
Recreation
Store atmospheric
carbon
Jobs
Provide numerous
wildlife habitats
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Fig. 10-4, p. 193
Economic value of forests
• Benefits: fuel, shelter,
transportation (boats), paper
• Helped society achieve a high
standard of living
• Logging Locations:
- Boreal Forests: Canada,
Russia
- Rainforests: Brazil,
Indonesia
- Conifer Forests/Pine
Plantations: U.S.
In 2005, over 1/3 all forests were designated for timber production
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Demand for wood leads to deforestation
• Deforestation = the clearing and
loss of forests
- Alters landscapes and
ecosystems
- Degrades soil
- Causes species decline and
extinction
- Ruins civilizations
- Adds carbon dioxide to the air
Developing countries boost their economies and get land
for their growing populations by logging forests
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Types of Forests
• Old-growth forest: uncut or
regenerated forest that has
not been seriously disturbed
for several hundred years.
- 22% of world’s forest.
- Hosts many species with
specialized niches.
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Figure 10-5
Types of Forests
• Second-growth forest: a stand of trees resulting
from natural secondary succession.
• Tree plantation: planted stands of a particular tree
species.
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Figure 10-6
Loggers moved westward, searching for
large trees
• Primary forest = natural forest uncut by people
- Little remained by the 20th century
• Second-growth trees = grown to partial maturity after oldgrowth timber has been cut
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Deforestation is proceeding rapidly
worldwide
• Uncut tropical forests still remain in many developing countries
- Technology allows for even faster exploitation
- Deforestation is rapid in places such as Brazil and Indonesia
• Developing countries are so desperate for economic development,
they have few logging restrictions
- Short-term economic benefits go to foreign multinational
corporations
- Governments often help companies, at the expense of native
people
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“Timber famine” fears spurred forest
protection
• National forest system = a system of forest reserves and public
lands
- To grow trees, produce timber, protect watersheds, and ensure
future timber supplies
- Resulted from depletion of U.S. forests and fear of a “timber
famine”
- 77 million ha (191 million acres); 8% of the U.S. land area
• The U.S. Forest Service was established in 1905
- Manage forests for the greatest good of the greatest number
in the long run, including logging
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Federal agencies own land in the U.S.
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Timber is extracted from public and private
land
• Timber is extracted by private companies, even on public land
- Forest Service employees plan and manage timber sales
and build roads
- The companies log and sell the timber for profit
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Most logging occurs on private land
• But, millions of cubic feet per year are still logged from
national forests
- Timber harvesting remains stable in developed
countries
- Timber companies manage forests according to the
maximum sustained yield approach
• Management on public lands reflects economic forces,
along with social and political ones
- These change over time
- Public concern, changing management philosophies
and economics caused harvests to decrease
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Plantation forestry
• The timber industry focuses on timber plantations
- Fast-growing species
- Monocultures
- Even-aged trees = all trees are the same age
• Trees are cut at the end of the rotation time and replanted
- Plantations are crops, not functional forests
• Some harvesting methods maintain uneven-aged (mixed ages
of trees and species) tree stands
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Harvesting Trees
• Trees can be harvested
individually from diverse
forests (selective cutting), an
entire forest can be cut down
(clear cutting), or portions of
the forest is harvested (e.g.
strip cutting).
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Figure 10-9
(a) Selective cutting
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Fig. 10-9a, p. 198
(b) Clear-cutting
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Fig. 10-9b, p. 198
Trade-Offs
Clear-Cutting Forests
Advantages
Disadvantages
Higher timber yields
Reduces biodiversity
Maximum profits in
shortest time
Disrupts ecosystem
processes
Can reforest with fastgrowing trees
Destroys and
fragments wildlife
habitats
Short time to establish
new stand of trees
Leaves large openings
Needs less skill and
planning
Good for tree species
needing full or
moderate sunlight
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Increases water
pollution, flooding, and
erosion on steep
slopes
Eliminates most
recreational value
Fig. 10-11, p. 198
(c) Strip cutting
Uncut
Cut 1
year ago
Dirt road
Cut 3–10
years ago
Uncut
Stream
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Fig. 10-9c, p. 198
Question of the Day
• The largest area of old-growth forest in the United States
is located in
- Alaska
- Montana
- California
- North Carolina
- Michigan
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Harvesting: other methods
• Seed-tree cutting = a small number of seed-producing
trees are left standing to reseed the area
• Shelterwood cutting = a small number of trees are left to
provide shelter for the seedlings
• Selection systems = only select trees are cut
- Single tree selection = widely spaced trees are cut
- Group tree selection = small patches of trees are cut
• All methods disturb habitat
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PROTECTING/MANAGING
FORESTS
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Types and Effects of Forest Fires
• Depending on their intensity, fires can benefit or
harm forests.
- Burn away flammable ground material.
- Release valuable mineral nutrients.
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Figure 10-13
Fire policy also stirs controversy
• For over 100 years, the Forest Service
suppressed all fires
- But many ecosystems depend on
fires
- Fire suppression allows woody
accumulation, which produces
kindling for future fires
- Which are much worse
• Housing development near forests and
climate change will increase fire risk
• Ex. Malibu wildfires and increasing
severity of southwester fires
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Prescribed fires are misunderstood
• Prescribed (controlled) burns = burning areas of forests
under carefully controlled conditions
- Effective
- May get out of control
- Impeded by public misunderstanding and political
interference
• Healthy Forests Restoration Act (2003) = promotes
removal of small trees, underbrush and dead trees
- Passed in response to forest fires
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The National Forest Management Act (1976)
• Mandated that plans for renewable resource management had
to be drawn up for every national forest
• Guidelines included:
- Consideration of both economic and environmental factors
- Provision for species diversity
- Ensuring research and monitoring
- Permitting only sustainable harvests
- Protection of soils and wetlands
- Assessing all impacts before logging to protect resources
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Sustainable forestry is gaining ground
• Sustainable forestry certification = only products produced
sustainably can be certified
- International Organization for Standardization (ISO),
Forest Stewardship Council (FSC) have different standards
- Consumers look for logos to buy sustainably produced
timber
- Companies such as Home Depot sell sustainable wood
- Encourages better logging practices
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Solutions
Sustainable Forestry
• Identify and protect forest areas high in biodiversity
• Grow more timber on long rotations
• Rely more on selective cutting and strip cutting
• Stop clear-cutting on steep slopes
• Cease logging of old-growth forests
• Prohibit fragmentation of remaining large blocks
of forest
• Sharply reduce road building into uncut forest areas
• Leave most standing dead trees and fallen timber for
wildlife habitat and nutrient recycling
• Certify timber grown by sustainable methods
• Include ecological services of forests in estimating
their economic value
• Plant tree plantations on deforested and degraded land
• Shift government subsidies from harvesting trees to
planting trees
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Fig. 10-12, p. 199
Federal parks and reserves began in the U.S.
• National parks = public lands
protected from resource
extraction and development
- Open to nature appreciation
and recreation
- Yellowstone National Park
was established in 1872
• The Antiquities Act of 1906
- The president can declare
selected public lands as
national monuments
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The National Park Service (NPS)
• Created in 1916 to administer parks and monuments
- 388 sites totaling 32 million ha (72 million acres)
- Includes national historic sites, national recreation
areas, national wild and scenic rivers
- 273 million visitors in 2006
- Ex. Yellowstone & Yosemite
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National Wildlife Refuges
• Begun in 1903 by President Theodore Roosevelt
• 37 million ha (91 million acres) in 541 sites
• U.S. Fish and Wildlife Service administers refuges
- Management ranges from preservation to manipulation
- Wildlife havens
- Allows hunting, fishing, wildlife observation,
photography, education
- Ex. Hatchie River National Wildlife Refuge
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Wilderness areas
• Wilderness areas = area is offlimits to development of any kind
- Open to the public for hiking,
nature study, etc.
- Must have minimal impact on
the land
- Necessary to ensure that
humans don’t occupy and
modify all natural areas
• Established within federal lands
- Overseen by the agencies that
administer those areas
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Nonfederal entities also protect land
• Each U.S. state and Canadian province has agencies that
manage resources
- So do counties and municipalities
• Land trusts = local or regional organizations that
purchase land to protect it
- The Nature Conservancy is the world’s largest land
trust
- Trusts protect 4.1 million ha (10.2 million acres)
- Jackson Hole, Wyoming is protected by a land trust
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Parks and reserves are increasing
internationally
• Parks do not always receive necessary funding
- Paper parks = Areas protected on paper but not in reality
- World heritage sites = protected areas that fall under national
sovereignty but are designated or managed by the United
Nations
- 830 sites across 184 countries
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Biosphere reserves have several zones
• This can be a win-win situation for everyone
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Habitat fragmentation threatens species
• Contiguous habitat is chopped into small
pieces
- Species suffer
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The SLOSS dilemma
• Which is better to protect species?
- A Single Large Or Several Small reserves?
- Depends on the species: tigers vs. insects
• Habitat Corridors = protected land that allows animals
to travel between islands of protected habitat
- Animals get more resources
- Enables gene flow between populations
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ECOLOGICAL RESTORATION
• Restoration: trying to return to a condition as similar
as possible to original state.
• Rehabilitation: attempting to turn a degraded
ecosystem back to being functional.
• Replacement: replacing a degraded ecosystem with
another type of ecosystem.
• Creating artificial ecosystems: such as artificial
wetlands for flood reduction and sewage treatment.
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END
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Conclusion
• Resources must be managed sustainably to avoid
overexploitation and overharvesting
• Many nations have established federal and regional
agencies to manage publicly held land and natural
resources
• Resource management policies first emphasized
extraction then shifted into sustained yield and multiple
use
• Public support for land preservation resulted in parks,
wilderness areas and other reserves
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QUESTION: Review
If an area is managed for Maximum Sustained Yield, and
the area can support 100 organisms, how many organisms
will be allowed to remain in the area?
a)
b)
c)
d)
100
75
50
25
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QUESTION: Review
Which of the following is not part of the ecological value
of forests?
a)
b)
c)
d)
e)
Erosion prevention
Decreased flooding
Carbon storage
Climate moderation
All of the above are values of forests
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QUESTION: Review
Which of the following statement regarding forest
management is false?
a)
b)
c)
d)
Deforestation in the U.S. has occurred for centuries
Timber companies move on after an area is
deforested
Tropical countries have lost the majority of forests
so timber companies won’t be going there
Governments in developing countries help logging
companies at the expense of native people
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QUESTION: Review
Which agency manages national forests?
a)
b)
c)
d)
U.S. Fish and Wildlife Service
U.S. Forest Service
Bureau of Land Management
National Park Service
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QUESTION: Review
Tree harvesting by clear-cutting….
a)
b)
c)
d)
Cuts all trees in an area, leaving only stumps
Cuts most trees, but leaves some to produce seeds
Cuts most trees, but leaves some to shelter seedlings
Produces uneven-aged tree stands
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QUESTION: Review
The National Forest Management Act of 1976 guidelines
included all of the following, except:
a)
b)
c)
d)
Consideration of economic factors
Soil protection
Increased harvesting under times of economic stress
Provisions for species diversity
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QUESTION: Review
The Conservation Reserve Program:
a)
b)
c)
d)
Pays farmers subsidies to drain wetlands
Pays farmers subsidies to protect wetlands
Pays farmers to increase livestock on BLM lands
Encourages cities to drain wetlands for expansion
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QUESTION: Review
“Monumentalism” refers to:
a)
b)
c)
d)
Protecting very large trees
Protecting areas with large buildings
Growing the largest crops possible
Preserving lands with enormous or beautiful features
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QUESTION: Review
Which areas are off limits to all development?
a)
b)
c)
d)
National forests
National parks
Wilderness areas
BLM lands
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QUESTION: Review
How does habitat fragmentation threaten species?
a)
b)
c)
d)
Large lands are chopped into small pieces
Small lands are not protected
Species are able to find each other more easily
It does not threaten species
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QUESTION: Interpreting Graphs and Data
Which type of land ownership has more trees being cut
than growing?
a)
b)
c)
d)
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National forests
Other public forests
Forest industry land
Other private land
QUESTION: Interpreting Graphs and Data
Which area of the world had the largest increase in paper
consumption between 1990 and 2000?
a)
b)
c)
d)
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Africa
Asia
Europe
North America
QUESTION: Viewpoints
Should people be allowed to build homes alongside
national parks that periodically experience fire?
a) Yes, people should be allowed to build wherever
they want
b) Yes, but only if they carry enough insurance
c) No, the government should buy the land as a
buffer zone
d) I don’t care, I don’t own a home in a fire-prone
area
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QUESTION: Viewpoints
Should farmers and ranchers get federal subsidies to
protect their land?
a) Absolutely yes; we pay subsidies for everything
else
b) Maybe, if the farmer earns below a certain amount
of money
c) No; all subsidies are bad, regardless of their goals
d) I would agree, if I could get a subsidy
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