Terrestrial Biodiversity Powerpoint

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Chapter 10
 America’s
 Parks
sizes
“crown jewel”
are diverse and come in many different
 Purchases
have been made by government or
private individuals/companies
 Yellowstone
NP was the first (1872)
 John
Muir – S16 & S17
 Henry
 Aldo
David Thoreau
Leopold
 President
Teddy Roosevelt

Sierra Club (1892)

Audubon Society

The Nature Conservancy (1951) – has created
the world’s largest system of private natural
areas and wildlife sanctuaries in 30 countries.

National Park Service (1916) – manages the National Parks
System; falls under the Dept. of Interior

US Forest Service (1905) – manages and protects the forest
reserves.

US Fish and Wildlife Service (1940) –

National Wildlife Refuges – areas that have been set aside
for the protection of threatened or endangered species.
◦ responsible for identification and listing of,
◦ and monitoring the import of threatened and endangered
species.
◦ Responsible for administering the Endangered Species Act
1.
Air, noise and water pollution
2.
Invasion of non-native species
3.
4.
5.
Tourism – high number of park visitors can
degrade natural areas
LACK OF FUNDING
Pressure from developers, lumber and mining
companies

Parks can be viewed as habitat islands
surrounded by:
1. Logging
2. Industrial activity
3. Energy extraction (minerals, oil, coal)
4. Agriculture
5. Dissected by roads (very detrimental)
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Forest Reserve Act (1891)
Lacey Act (1900)
National Parks and Services Act (1916)
Migratory Bird Act (1918)
Taylor Grazing Act (1934)
Federal Aid in Wildlife Restoration Act (1937)
Wilderness Act (1964)
Smokey Bear Campaign (1970s)
Healthy Forests Restoration Act (2003)


Allows activities such as camping, kayaking,
canoeing and fishing; NOT motor boating
Offers protection to rivers or segments of
rivers with
◦ Cultural and historical value
◦ Wildlife and scenic value
◦ Recreational value

Around 1800 – healthy population

1850–1900 - decline due to human
activity

U.S. Endangered Species Act (1973)

1995–1996 - relocation of gray wolves
to Yellowstone Park

2008 - Gray wolf removed from
Endangered Species list

Keystone species


Cull herds of bison, elk
and caribou


Keep the coyote
population down

Provide meat for
scavengers
Environmentalists

Leave the park and
attack cattle and sheep
Kill big-game animals
Mining and logging
companies feared
having to halt
operations on wolfpopulated federal land
Farmers, Hunters,
Loggers and Miners

Forest ecosystems provide ecological services far greater
in value than the value of raw materials obtained from
forests.

Unsustainable cutting and burning of forests, along with
diseases and insects, are the chief threats to forest
ecosystems.

Tropical deforestation is a potentially catastrophic problem
because of the vital ecological services at risk, the high rate
of tropical deforestation, and its growing contribution to
global warming.

About 5% of Earth’s
remaining areas are
protected either strictly
or partially by law.


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About 20% of Earth’s
land area is needed to
adequately preserve
biodiversity.
Wilderness
Forests cover about
30% of the United
States.
About 40% of the
forests in the US are
protected.
Forests

Old-growth or primary forest
◦ An uncut or regenerated forest that has not been
disturbed by human activities or natural disaster
for several hundred years
◦ 36% of world’s forests

Second-growth forest
◦ A stand of trees resulting from natural secondary
ecological succession; once cleared for timber or
for conversion for cropland, or by natural forces
(fires, hurricanes, volcanic eruption).
◦ 60% of world’s forests

Tree plantation, tree farm or commercial forest
◦ 4% of world’s forests
 Uniformly aged
 Genetically uniform
 Harvested by clear-cutting
 May supply most of the industrial wood in the
future
 Have decreased the need for timber production
in the US
Short rotation cycle of cutting and re growth of a
monoculture tree plantation

Support energy flow and
chemical cycling

Reduce soil erosion

Absorb and release water

Purify water and air

Influence local and regional
climate

Store atmospheric carbon

Habitats

Forests valued for ecological services
◦ Nutrient cycling
◦ Climate regulation
◦ Erosion control
◦ Waste treatment
◦ Recreation
◦ Raw materials

$4.7 Trillion per year

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Increased erosion
Sediment runoff into waterways
Habitat fragmentation
Loss of biodiversity
Invasion by
◦ Nonnative pests
◦ Disease
◦ Wildlife species

Clear cutting
◦ Removal of all trees
from an area
◦ Allows for maximum
profit in shortest
amount of time
◦ Results in
 Erosion and water
pollution
 Increased flooding
 Habitat fragmentation
 Loss of biodiversity
Selective cutting
•
•
•
mature trees cut
singly or in
groups
Cutting trees of
different sizes,
ages and species
Allows for uneven
age; higher
diversity
Major Tree Harvesting Methods
(cont.)
Strip-cutting
• A variation clearcutting
• Involves clear-cutting
a narrow corridor of
land, allowing a few
years for
regeneration, then
logging another strip
above the previous
strip(s).
(a) Selective cutting
(b) Clear-cutting
Clear stream
Muddy
stream
(c) Strip cutting
Uncut
Cut 1 year ago
Dirt road
Cut 3–10 years ago
Uncut
Clear stream
Stepped Art
Fig. 10-6a, p. 219
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
Burn fast and quick; kill
seedlings and small trees
but spare most large trees
Ecological Benefits : burn
away flammable ground
material , free valuable
mineral nutrients tied up in
decomposing litter and
undergrowth , release seeds
from pine cones , stimulate
germination of certain tree
seeds, help control tree
diseases and insects
Crown Fires



Extremely hot fire
that leaps from tree
top to tree top
burning whole trees.
Occur in forests that
have not
experiences surface
fires for decades
Can destroy
vegetation, kill wild
life, increase soil
erosion, sterilize the
soil, and burn or
damage human
structures

The Smokey Bear educational campaign
Prescribed fires
Allow fires on public lands to burn
Protect structures in fire-prone areas
Thin forests in fire-prone areas

2003 Healthy Forests Restoration Act

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

◦ Pros – clear away fire prone trees and underbrush
◦ Cons – cut down economically valuable medium-sized and
large trees in 71% of the country’s national forests

Introduction of
foreign diseases and
insects
◦ Accidental
◦ Deliberate

Global warming
◦ Rising temperatures
◦ Trees more
susceptible to
diseases and pests
◦ Drier forests: more
fires
◦ More greenhouse
gases
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Cover about 6% of Earth’s area
More than ½ of the world’s tropical forests
are located in Brazil, Indonesia, Zaire and
Peru
More than ½ have already been cleared or
degraded

Deforestation
◦ Tropical forests
 Especially in Latin
America (Brazil),
Indonesia, and Africa
◦ Boreal forests
 Especially in Alaska,
Canada, Scandinavia,
and Russia
Deforestation in Thailand
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Forests of the eastern United States decimated
between 1620 and 1920
Grown back naturally through secondary ecological
succession
Biologically simplified tree plantations reduce
biodiversity
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Majority of loss
since 1950
Brazil and
Indonesia tropical
forest loss
Role of
deforestation in
species’ extinction
NATURAL
CAPITAL
DEGRADATION
Major Causes of the Destruction and Degradation of Tropical Forests
Basic Causes
Secondary Causes
• Not valuing ecological services
• Crop and timber exports
• Government policies
• Poverty
• Population growth
Cattle
ranching
• Roads
• Fires
• Settler farming
• Cash crops
Tree
plantations
• Cattle ranching
• Logging
• Tree plantations
Logging
Cash crops
Settler
farming
Roads
Fires
Fig. 10-15, p. 225

Population growth

Poverty

Oil extraction

Massive foreign debt

We can sustain forests by emphasizing the
economic value of their ecological services,
protecting old-growth forests, harvesting trees
no faster than they are replenished, and using
sustainable substitute resources.

Collins Pine
◦ Owns and manages protective timberland

Forest Stewardship Council
◦ Nonprofit
◦ Developed list of environmentally sound practices
◦ Certifies timber and products

Improve the efficiency
of wood use
◦ Reduce construction
waste
◦ Reduce the amount of
junk mail
◦ Use laminated boards

Make tree-free paper
◦ Kenaf
◦ Hemp

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Fuelwood – most common use of trees worldwide
Possible solutions
◦ Establish small plantations of fast-growing fuelwood trees
and shrubs
◦ Burn wood more efficiently
◦ Solar or wind-generated electricity
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Haiti: ecological disaster
South Korea: model for successful reforestation

Reduce fuelwood demand

Practice small-scale sustainable agriculture and forestry in
tropical forest
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Debt-for-nature swaps
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Conservation concessions
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Use gentler logging methods

Buy certified lumber and wood products

Green Belt Movement: 1977
◦ Self-help group of women in Kenya
◦ Success of tree planting

Nobel Peace Prize: 2004
SOLUTIONS
Sustaining Tropical Forests
Prevention
Protect the most diverse
and endangered areas
Educate settlers about
sustainable agriculture
and forestry
Restoration
Encourage
regrowth through
secondary
succession
Subsidize only
sustainable forest use
Protect forests with
debt-for-nature swaps
and conservation
concessions
Certify sustainably grown
timber
Reduce poverty
Slow population growth
Rehabilitate
degraded
areas
Concentrate farming
and ranching in
already-cleared
areas
Fig. 10-19, p. 231

We can sustain the productivity of grasslands
by controlling the number and distribution of
grazing livestock and restoring degraded
grasslands.

Important ecological services of grasslands
◦ Soil formation
◦ Erosion control
◦ Nutrient cycling
◦ Storage of atmospheric carbon dioxide in biomass
◦ Maintenance of diversity

Overgrazing of
rangelands
◦ Reduces grass cover
◦ Leads to erosion of soil by
water and wind
◦ Soil becomes compacted
◦ Enhances invasion of plant
species that cattle won’t eat

Malapi Borderlands
◦ Management success story
The most widely used method for sustainable management
of rangeland is controlling the number of grazing animals
and the duration of their grazing.
 Rotational grazing at water holes and feeding areas
 Suppress growth of invasive species
◦ Herbicides
◦ Mechanical removal
◦ Controlled burning
◦ Controlled short-term trampling
 Replant barren areas with native grass seeds and fertilizer
 Protect riparian areas from overgrazing
 Reduce soil erosion
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American southwest:
population surge since
1980
Land trust groups: limit
land development
Reduce the harmful
environmental impact of
herds
◦ Rotate cattle away from
riparian areas
◦ Use less fertilizers and
pesticides
◦ Operate ranch more
economically

Sustaining biodiversity will require protecting
much more of the earth’s remaining
undisturbed land area as parks and nature
reserves.


Worldwide: 1100
major national
parks
Parks in
developing
countries
◦ Greatest
biodiversity
◦ 1% protected
against
 Illegal animal
poaching
 Illegal logging
and mining
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58 Major national parks in the U.S.
Biggest problem may be popularity
◦ Noise
◦ Congestion
◦ Pollution
◦ Damage or destruction to vegetation and wildlife
Repairs needed to trails and buildings

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Gray wolves prey on elk and push them to a higher
elevation
◦ Re growth of aspen, cottonwoods, and willows
◦ Increased population of riparian songbirds
Reduced the number of coyotes
◦ Fewer attacks on cattle
Wolf pups susceptible to parvovirus carried by dogs
Conservationists’ goal: protect 20% of the
earth’s land
 Cooperation between government and private
groups
 Nature Conservancy
 Eco-philanthropists
 Developers and resource extractors opposition
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Large versus small reserves
The buffer zone concept
◦ United Nations: 529 biosphere reserves in 105
countries
Habitat corridors between isolated reserves
◦ Advantages – allows migration by vertebrates that
need large ranges, migration of populations when
environment deteriorate
◦ Disadvantages – can threaten isolated populations
Biosphere Reserve
Core area
Research
station
Visitor
education
center
Buffer zone 1
Human
settlements
Buffer zone 2
Fig. 10-24, p. 237
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1963–1983: cleared
much of the forest
1986–2006: forests grew
from 26% to 51%
◦ Goal: to reduce net
carbon dioxide
emissions to zero by
2021
Eight zoned mega
reserves
◦ Designed to sustain
around 80% of Costa
Rica’s biodiversity
Wilderness Act of 1964
 How much of the United States is
protected land?
 Road Less Rule
 2005: End of “Road Less areas”
within the national forest system

We can help sustain biodiversity by identifying severely
threatened areas and protecting those with high plant
diversity and those where ecosystem services are being
impaired.
Sustaining biodiversity will require a global effort to
rehabilitate and restore damaged ecosystems.
Humans dominate most of the earth’s land, and
preserving biodiversity will require sharing as much
of it as possible with other species.
Map global ecosystems; identify species
 Locate and protect most endangered species
 Restore degraded ecosystems
 Development must be biodiversity-friendly
 Are new laws needed?
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Areas especially rich in plant and animal species
that are found nowhere else and are in great
danger of extinction or serious ecological
disruption.
These areas cover only a little over 2% of the
earth’s land surface but contain 52% of the
world’s plant species and 36% of all terrestrial
vertebrates.
These areas are the only homes for more than
1/3 of the planet’s known terrestrial plant and
animal species.
1988: Norman Myers
◦ Identify biodiversity hot spots rich in plant
species
 Not sufficient public support and funding
 Drawbacks of this approach
◦ May not be rich in animal diversity
◦ People may be displaced and/or lose access
to important resources

Biodiversity
Hotspots in the
U.S.
Top Six Hotspots
1 Hawaii
2 San Francisco
Bay area
3 Southern
Appalachians
4 Death Valley
5 Southern California
6 Florida Panhandle
Concentration of rare species
Low Moderate
High
Biodiversity Hotspots in the US
Fig. 10-27, p. 241
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Eastern Arc Mountains of Tanzania, Africa
◦ Highest concentration of endangered species on
earth
Threatened due to
◦ Killing of forests by farmers and loggers
◦ Hunting
◦ Fires

U.N. Millennium Ecosystem Assessment: 2005
◦ Identify key ecosystem services
◦ Human activities degrade or overuse 62% of the
earth’s natural services

Identify highly stressed life raft ecosystems

Study how natural ecosystems recover
◦
◦
◦
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Restoration
Rehabilitation
Replacement
Creating artificial ecosystems
How to carry out most forms of ecological restoration
and rehabilitation
◦
◦
◦
◦
Identify what caused the degradation
Stop the abuse
Reintroduce species, if possible
Protect from further degradation

Guanacaste National Park restoration project
◦ Relinked to adjacent rain forest
◦ Bring in cattle and horses – aid in seed dispersal
◦ Local residents – actively involved

Preventing ecosystem damage is cheaper than
restoration

About 5% of the earth’s land is preserved from
the effects of human activities

Win-Win Ecology: How Earth’s Species Can Survive in
the Midst of Human Enterprise, by Michael L.
Rozenweig, 2003
◦ Reconciliation or applied ecology
◦ Community-based conservation
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Belize and the black howler monkeys
Protect vital insect pollinators
Bluebird protection with special housing boxes
Berlin, Germany: rooftop gardens
San Francisco: Golden Gate Park
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1970s: Blackfoot River Valley in Montana threatened
by
◦ Poor mining, logging, and grazing practices
◦ Water and air pollution
◦ Unsustainable commercial and residential
development
Community meetings led to
◦ Weed-pulling parties
◦ Nesting structures for waterfowl
◦ Developed sustainable grazing systems
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Adopt a forest
Plant trees and take care of them
Recycle paper and but recycled products
Buy sustainably produced wood products
Choose wood substitutes- bamboo
Help to restore a degraded forest or
grassland
Landscape your yard with a diversity of plants
natural to the area
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