10-2 How Should We Manage and
Sustain Forests?
• Concept 10-2 We can sustain forests by emphasizing
the economic value of their ecological services,
removing government subsidies that hasten their
destruction, protecting old-growth forests,
harvesting trees no faster than they are replenished,
and planting trees.
Solution: Sustainable Forestry
• Biodiversity researchers and a growing number of
foresters have called for more sustainable forest
management
• Identify and protect forest areas
high
________
in biodiversity
selective and
• Rely more on _____________
strip
_____________
cutting
old-growth
• Stop logging in _________________
forests
road building in uncut forest areas
• Reduce _________
• Leave dead or fallen timber for wildlife
_____________
and nutrient _______________
habitat
cycling
Solution: Sustainable Forestry
deforested
• Put tree plantations only on _________________
or
degraded land
• ________________
timber grown by
Certify
sustainable methods
ecological
• Include ____________________
services of forests in estimates of
their economic value
Science Focus: Certifying Sustainably
Grown Timber
company
• Collins Pine is a forests products _____________that
owns and manages large areas of timberland in
California, Oregon and Pennsylvania
• Has used selective cutting since the 1940s
• Each year their land is evaluated by a subsection of
Forest
Stewardship Council and
the _____________
_______________
they are awarded with a _______
FSC logo on their
products
5%
• Only ______
of the world’s forest area in 82 countries
has been certified according to FSC standards
We Can Improve the Management
of Forest Fires
Smokey
Bear
• In the U.S., the _____________
_________
educational campaign has saved many lives and
prevented countless forest fires
• Downside?…the advertising campaign has convinced
bad
much of the public that all forest fires are ________
surface - fires
• We actually need _________________
to prevent the
build up of flammable underbrush which may cause
crown fires
• To reduce this risk, one strategy is to conduct
_________________
fires…setting small, contained
prescribed
surface fires to reduce the buildup of underbrush
• A second strategy is to allow some fires on public
burn
lands to ____________
• A third strategy is to __________
out a forest zone
thin
houses
surrounding _____________
or other fire prone
buildings
• A fourth strategy is to thin forest areas vulnerable to
fire by removing ____________
trees
small
We Can Reduce the Demand for
Harvested Trees
• One way to reduce the pressure on forest
ecosystems is to improve the efficiency of wood
________
use
• 60% of U.S. wood consumed is wasted
• This results from…
•
•
•
•
construction materials
Inefficient use of ____________________
packaging
Excess __________________
Overuse of _________
mail
junk
recycling
Inadequate paper __________________
We Can Reduce the Demand for
Harvested Trees
• We can reduce our need to
harvest trees by making
paper from
tree-free resources
______________
• China uses
_______________
rice straw
• U.S. uses a small amount
kenaf
of __________
(kuhNAHF)
• Other possible
options…hemp, kudzu vine
kenaf
• So to reduce our demand for harvesting trees, we
need to be…
waste
• Reducing ________________
• Finding ________________
alternatives
sustainable
• Embracing _________________
use
Case Study: Deforestation and the
Fuelwood Crisis
half
• About _______
of the wood we harvest world-wide
fuel
is used for __________
• Less-developed countries use fuelwood for
_______________
and _______________
heating
cooking
• Ex: Haiti was once a tropical paradise , but now it is an
disaster
ecological _______________
because its trees were
harvested for fuelwood
Mangrove Forest in Haiti Chopped
Down for Fuelwood
Fig. 10-18, p. 232
Case Study: Deforestation and the
Fuelwood Crisis
• Possible solutions
• Establish small plantations of _______________
fast-growing
fuelwood trees and shrubs
• Burn wood more efficiently with better
stoves
_____________
(that also produce less pollution)
• Solar or wind-generated electricity
waste
• Burn garden ______________
Governments and Individuals Can Act
to Reduce Tropical Deforestation
small-scale
• Help settlers to develop ____________________
sustainable agriculture and forestry in tropical forest
• Government _________________
for forest land
protection
• Debt-for-nature swaps/conservation concessions
technical
• Example: Brazil’s dairy farmers receive _____________
assistance as long as they are reforesting and maintaining
doubled
tripled
their land…____________
milk yields and ______________
their incomes
• Plant trees
• Buy certified lumber and wood products
Solutions
Sustaining Tropical Forests
Prevention
Restoration
Protect the most diverse and
endangered areas
Encourage regrowth
through secondary
succession
Educate settlers about
sustainable agriculture and
forestry
Subsidize only sustainable
forest use
Protect forests through
debt-for-nature swaps and
conservation concessions
Rehabilitate
degraded areas
Certify sustainably grown
timber
Reduce poverty
Slow population growth
Concentrate farming and
ranching in alreadycleared areas
Fig. 10-19, p. 233
10-3 How Should We Manage and
Sustain Grasslands?
• Concept 10-3 We can sustain the productivity of
grasslands by controlling the number and distribution
of grazing livestock, and by restoring degraded
grasslands.
Some Rangelands Are Overgrazed (1)
• After forests, grasslands are the ecosystems most
widely used and altered by humans
• Rangelands
unfenced
• ____________________
grasslands in temperate and
tropical climates that provide forage for animals
• Grazing = _________________
grass
• Browsing = __________________
shrubs
• Pastures
• ____________________
grasslands and fenced
managed
meadows used for grazing livestock
Some Rangelands Are Overgrazed (2)
• Important ecological services of grasslands
•
•
•
•
•
____________________
formation
Soil
control
Erosion _____________________
cycling
Nutrient _________________
CO2
Storage of atmospheric _______
in biomass
Maintenance of biodiversity
• Cattle and sheep currently graze on about _____
42% of
the world’s grasslands…estimated to increase to
70% by 2050.
_______
Some Rangelands are Overgrazed (3)
• Overgrazing of rangelands occurs when too many
animals graze for too long…damaging the ________
roots
of grasses and exceeding the area’s _____________
carrying
capacity
_______________
• Reduces grass cover
• Leads to erosion of soil by water and wind
• Soil becomes compacted…diminishes capacity to hold
water
_____________
• Enhances invasion of plant species that cattle won’t
eat
Natural Capital Degradation: Overgrazed and
Lightly Grazed Rangeland
Fig. 10-20, p. 234
Case Study: The Malpai Borderlands
• Malpai Borderlands
• Grasslands located by the ___________________
Arizona New Mexico
__________________
border
• For more than a century, ranchers there….
overgrazing
• Allowed __________________
suppressed
• _________________
fires….allowed trees and shrubs
to replace grasses
• Management success story
• Since 1993, ranchers, scientists, environmentalists, and
governing agencies began working together to restore
controlled
the grasslands – conducted periodic _______________
burns
Natural Capital Restoration: San Pedro
River in Arizona
riparian
__________________
zone
Fig. 10-21, p. 235
We Can Manage Rangelands More
Sustainably (1)
• More sustainable management of rangelands…
Rotational
• _________________
grazing – cattle are confined by
portable fencing to one area for a ____________
time
short
and then moved to a new location
invasive
• Suppress growth of ________________
species
•
•
•
•
Herbicides
Mechanical removal
Controlled burning
Controlled short-term ______________________
trampling
• Replant barren areas with ___________
grasses and
native
applying fertilizer…more expensive option
Case Study: Grazing and Urban
Development the American West
• American southwest population surge since 1980
• Some ranchers have been selling their land to
_________________
developers
• To sustain our remaining grasslands, we have been
preserve
working to __________________
cattle ranches
• Land trust groups pay ranchers for conservation
_________________
- deed restrictions that bar future
easements
owners from developing the land
zone
• Pressuring local governments to ___________
the land
Review Questions
• What does an FSC logo indicate?
It is certified as sustainably made
• Why are surface fires needed?
To remove flammable underbrush & maintain grasslands
• What is meant by the term “fuelwood crisis”?
½ of our wood is used for fuel by LDCs
and they need alternatives
• What methods will help us to sustain grasslands?
Rotational Grazing
Suppress Invasive Species
Replant/Fertilize