Download Chapter 11: Forestry and Resource Management

Chapter 11: Forestry
and Resource
Management
*Renewable resources cannot run out,
no matter how much humans use
them.*
-Is this statement true or false? Support
your answer.-
11.1 Resource Management
Resources:
• renewable (soil)
• Nonrenewable (fossil
fuels)
• Goal: 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
• Forests
• Wild animals
• Clean water
• Soil
Managing of resource harvesting so that
resources are not depleted. Influenced by
•Politics
•Economics
•Social issues
Soil & Fresh Water
• Always being made by
natural processes
(weathering/erosion/de
composition)
• Topsoil- fertile top layer
made very slowly 1in100 years to form.
• Continually supplied by
natural processes
• Maintain quality of
water
• Necessary for
agriculture, wildlife,
humans, functioning
ecosystems.
Wild Animals & Forests
• Hunting for food (gameanimals hunted legally) to
maintain populations
• Populations are fallingdeforestation habitat
fragmentation.
Management is very
important
• Overfishing despite laws
(Cod)
• Poaching
• Wood from trees-timber
raw material for variety of
products
• Essential for living
• Developing countriesforests are disappearing at
alarming rate
1)Maximum Sustainable Yield (MSY)
Goal: harvest maximum
resources without
compromising future
harvests
PROBLEMS:
• affect interactions between
species & alter entire
ecosystems.
• Determining target
population size largely a
matter of trial & error.
2) Ecosystem-Based Forest
Management
• Goal: harvest resources
while minimizing effects
on the rest of the
ecosystem
• Ecologically sensitive
areas carefully monitored
& protected; resources
harvested selectively.
Ecosystem Based Management
PROBLEM:
Ecosystems complex, choosing
which areas to
protect & which to
harvest -challenge.
Requires a lot of
ecosystem
knowledge
3) Adaptive Forest Management
• Goal: gather data from areas
managed in different ways, &
develop a customized
management plan based on the
results
• Management practices
continually monitored &
adjusted.
• Can be time-consuming and
may require changing
established practices
• 11.2 Forests & Their Resources
What about a forest is important?
Value of Forests
•Ecological value:
•Provide habitat for
organisms
•Source of biodiversity
•Prevent erosion
•Purify water
•Store carbon, release
oxygen
Pg. 331 add figure 7- Mature Forest Structure
Value of Forests
Economic value:
•Timber for
lumber & fuel
•Source of food
•Raw material
for many
medicines
Logging
• Un-even aged=More biodiversity trees of different ages
offer greater variety of habitats
• All methods disturb forest communities
• Changes forest structure & composition
• Increases soil erosion
• Lower drinking water quality
• Cause flooding
Deforestation- clearing of forest &
replacement of it by other land use
•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
Timber Harvesting Methods
Three Methods
• Three methods: Clearcutting, seed-tree or
shelterwood approach, and
selection system
• Either even-aged
or 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 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.
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
11.3 Forest Management
U.S. National Forests
• Early 1900’s eastern deciduous forest almost
disappeared –Deforestation caused a timber
famine
• Led to formation of U.S. national forest
system- public lands set aside to grow trees
for timber & to protect watersheds.- managed
by the Forest Service
U.S. National Forests
established
in 1905
Today,
managed
by to
the U.S.
Forest Service,
for
Originally
set aside
timber,
recreation,
wildlife habitat, and mining
grow trees
for timber
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 (Recreation,
wildlife habitat mining etc.) and
maximum sustainable yield.
NFMA
Logging has
declined in national
forests since
passage of the Act,
but policies are
vulnerable to
political influence
Private Land
• Most harvesting from plantations of fast growing
trees in NW and S.
• Monocultures- large scale plantings of a single
crop.
• All planted at the same time (even aged)
• Less biodiversity
• Some plantations are harvested –uneven aged.
Fire Policies
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.
Healthy Forests Restoration Act
• Goal: make forests less
fire-prone. Law
encourages more small
prescribed burning
• Removes small trees,
underbrush and snags –
salvage logging
• Problem:
Removing snags
-erosion
-soil damage
-Slows regrowth
-Animals depend on snags
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.