Chapter 11: Forestry and Resource Management

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Chapter 11: Forestry
and Resource
Management
Mr. Manskopf
Notes also at
http://www.manskopf.com
Essential Questions Covered
• Describe the impact of human
activities on the land.
• What are some local and federal laws
governing land usage.
Section 1 Resource Management
• Explain the importance of managing
specific renewable resources.
• Describe several resource management
approaches.
Renewable Resource Management
• Resources are either
renewable, such as soil,
or nonrenewable, such
as fossil fuels.
• Goal is sustainability—
resource use that occurs
only as fast as can be
naturally replaced.
What are some examples of
RENEWABLE RESOURCES?
Renewable Resource Management
Must balance human
and ecological needs
What are some of our
economic and
ecological needs in:
• Forests
• Wild animals
• Clean water
• Soil
1)Maximum Sustainable Yield (MSY)
Goal: To harvest maximum
resources without
compromising future
harvests
PROBLEMS:
• MSY can affect interactions
between species and alter
entire ecosystems.
• Determining target
population size is largely a
matter of trial and error.
2) Ecosystem-Based Forest
Management
• Goal: To harvest
resources while
minimizing effects on the
rest of the ecosystem
• Ecologically sensitive
areas are carefully
monitored and protected;
resources are harvested
selectively.
Ecosystem Based Management
PROBLEM:
Ecosystems are
complex, so choosing
which areas to
protect and which to
harvest is a
challenge.
Requires a lot of
ecosystem
knowledge
3) Adaptive Forest Management
• Goal: To gather data from areas
managed in different ways, and
develop a customized
management plan based on the
results
• Management practices are
continually monitored and
adjusted.
• Can be time-consuming and
may require changing
established practices
Section 1 Review
• Explain the
importance of
managing specific
renewable resources.
• Describe several
resource
management
approaches.
Section 1 Quiz
1) Renewable resources include soil,
fresh water, wild animals, and
A. minerals.
B. coal.
C. timber.
D. petroleum.
2) Which approach to resource
management aims to harvest
resources in ways that minimize
impact on the ecosystem and
processes that provide the resource?
A. maximum sustainable yield
B. ecosystem-based management
C. adaptive management
D. watershed management
3) A renewable resource is harvested
sustainably if
A. the amount of replacement is less
than the amount harvested.
B. the amount of replacement is equal
to the amount harvested.
C. soil erosion is prevented.
D. replacing trees costs less than
harvesting trees.
Short Answer
4) Pick one of the types “Management
Approaches” (Maximum Sustained
Yield, Ecosystem-Based or Adaptive)
and explain at least 1 pro and con of
that approach.
Section 2 Forests and Their Resources
• List several ecological and economical
values of forest resources.
• Describe the costs and benefits of
different methods of timber
harvesting.
• Analyze impacts of deforestation
around the world.
Value of Forests
•Ecological value:
•Provide habitat for
organisms
•Source of biodiversity
•Prevent erosion
•Purify water
•Store carbon, release
oxygen
Value of Forests
Economic value:
•Timber for
lumber and fuel
•Source of food
•Raw material
for many
medicines
Timber Harvesting Methods
Three Methods
• Three methods: Clearcutting, seed-tree or
shelterwood approach, and
selection system
• May result in even-aged
or uneven-aged regrowth
• Even-aged regrowth
tends to be less
biodiverse than
uneven-aged regrowth
1) Clear Cutting
• Involves cutting down all
trees in a region, resulting in
even-aged stands of
regrowth
• Changes abiotic conditions
in the area, including light
penetration, precipitation,
wind, and temperature
Clear Cutting
• Benefit: Cost
efficient
• Costs: Entire
communities usually
displaced or
destroyed; causes
soil erosion.
2) Seed-Tree and Shelterwood
Approaches
•Seed-tree: Small
numbers of mature,
healthy trees are left
standing, to reseed the
area.
•Shelterwood: Involves
leaving a few mature
trees standing to provide
shelter for seedlings
Shelterwood
Seed-Tree and Shelterwood
Approaches
•Benefit: Less
damaging than
clear-cutting
•Cost: As with clearcutting, leads to
mostly even-aged
regrowth
Selection Logging
3) Selection Logging
•Relatively few trees
are cut at once
under a selection
system.
•Selection can involve
widely spaced single
trees or groups.
Selection Logging
• Benefits:
–More biodiverse,
uneven-aged growth
–Less overall
environmental damage
• Costs:
–Machinery disturbs
forest interior.
–Expensive process
–More dangerous for
loggers
Deforestation
•Deforestation in tropical
and arid regions has the
most negative effects due
to loss of biodiversity and
desertification risk
respectively.
•Globally, deforestation
adds CO2 to Earth’s
atmosphere
Deforestation in U.S.
•Deforestation for timber
and farmland facilitated
U.S. expansion.
•By the early 1900s, very
little
old-growth forest (forest
that has never been
logged) remained in the
United States.
Old-Growth Forests
• Have never
been logged
• Contain rich
species
diversity
Worldwide Deforestation
• Timber from old-growth
tropical rain forests is a source
of income in developing
nations.
• Advanced technology enables
deforestation to occur far faster
• Deforestation of tropical rain
forests has an enormously
impact on global species
diversity.
Before and After
Desertification
Deforestation
•Decreased soil fertility from erosion
•Runoff of eroded soil into aquatic systems
•Premature extinction of species with
specialized niches
•Loss of habitat for migratory species such as
birds and butterflies
•Regional climate change from extensive clearing
•Releases CO2 into atmosphere from burning
and tree decay
•Accelerates flooding
Section 2 Review
• List several ecological and economical
values of forest resources.
• Describe the costs and benefits of
different methods of timber
harvesting.
• Analyze impacts of deforestation
around the world.
Section 2 Quiz
1) One disadvantage of the selection
system of timber harvesting is that it
A. produces even-aged stands.
B. produces a monoculture.
C. causes soil erosion.
D. is more dangerous for loggers.
2) Deforestation is particularly
harmful in arid regions because it
can lead to
A. desertification.
B. a massive loss of biodiversity.
C. loss of jobs.
D. a decrease in greenhouse
gases.
3) Which type of forest most likely
contains the greatest variety of
habitats?
A. old-growth forests
B. even-aged stands
C. plantations
D. monocultures
Short Answer
4) How do forest plants prevent
soil erosion?
5) Which
method of
timber
harvesting
leads to
the
greatest
unevenaged
stands of
regrowth?
6) Which
method of
timber
harvesting is
likely to be
most costly
for a timber
company?
Why?
Section 3 Forest Management
• Explain how logging is managed in U.S.
National Forests.
• What impacts does fire suppression in
U.S. forests have?
• What are ways consumer demand
impacts forestry practices?
Figure 11-6b
Page 198
National parks
and preserves
National
forests
(and Xs) National wildlife refuges
Figure 11-6a
Page 198
National parks and preserves
National forests
(and Xs) National wildlife refuges
• Most logging in the U.S. takes place on private
land, but timber companies are also allowed
to harvest trees in National Forests under
supervision by the U.S. Forest Service.
U.S. National Forests
Today, managed
Originally
set aside
by to
the U.S.
Forest Service,
for
established
in 1905
grow trees
timber,
recreation,
for timber
wildlife habitat, and mining
National Forest Management
Act (1976)
•Requires that resource
management plans be
made for each national
forest
•Plans are required to be
consistent with the
principles of multiple
use and maximum
sustainable yield.
NFMA
Logging has
declined in national
forests since
passage of the Act,
but policies are
vulnerable to
political influence
Fire Policies
What is the cause of
most forest fires?
Surface fire
Crown fire
Fire Suppression
•Negative effects on
ecosystems that
depend on fire
•Fuel for future fires
accumulates (limbs,
sticks, and leaf
litter).
•Suppressing small
fires increases
likelihood of larger,
dangerous fires.
Fire Suppression
Prescribed Burns:
* Carefully controlled
burning helps to
reduce fuel buildup
and to restore
ecosystems.
•Rarely burn out of
control, but occasional
accidents frighten
the public.
Sustainable Forestry Products
• Independent organizations
certify that wood products are
produced sustainably.
• Forest Stewardship Council
(FSC) has the strictest
standards and most widely
accepted certification process.
• Certified wood costs more to
produce, but will be supplied
by timber companies if there is
demand.
Section 3 Review
• Explain how logging is managed in
U.S. National Forests.
• What impacts does fire suppression
in U.S. forests have?
• What are ways consumer demand
impacts forestry practices?
Section 3 Quiz
1) Prescribed burns are fires that
A. are caused by lightning.
B. are set by humans.
C. never get out of control.
D. increase the risk of injury.
2) The National Forest Management Act
A. requires plans for national forests that
follow multiple use and maximum sustainable
yield guidelines.
B. requires plans for national forests that
follow multiple use and ecosystem-based
management guidelines.
C. encourages prescribed burning as a means
of protecting national forests.
D. promotes the removal of small trees and
underbrush by timber companies.
3) Smokey the Bear’s message
resulted in
A. an increased number of forest
fires.
B. an increase in biodiversity.
C. suppression of all forest fires.
D. a loss of lives.
4) Fire suppression can result in
a(n)
A. increase in animal habitats.
B. buildup of material that fuels
future fires.
C. decrease in property damage.
D. an increase in the jack pine
population.
5) Prescribed burns
A. are carefully controlled.
B. cannot be controlled.
C. cause fuel buildup.
D. cause permanent damage to
ecosystems.
6) If a wood product is certified by
the Forest Stewardship Council, it was
produced
A. using sustainable methods.
B. from trees grown on a plantation.
C. from recycled materials.
D. because consumers demanded it.
The End
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