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Terrestrial Ecosystems—
Management and Threats
Chapter 10
Forests
 Types of Forests (coniferous, temperate, and
tropical)
 Cover 30% of the earths surface
 tropical forests account for more than half
 old growth forests (not seriously disturbed
for 100+ years)--36%
 second-growth forests (result from
secondary succession)--60%
 tree plantation (managed forest, same
species, same age)--4%
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Ecological and Economic
Services
 Remove carbon dioxide and produce oxygen
 temperature stabilization (climate change)
 Hold soil in place
 minimize flooding
 recharge groundwater
 provide with food/medicine
 home for animals and humans
 provide a source of income
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Major Threats
 Loss of habitat is the single biggest cause of species
extinction!
 Unsustainable logging (deforestation)
 use wood for biofuel, lumber, paper, exotic woods for
furniture, flooring, etc.

harvesting illegally
 selective cutting, clear cutting, strip cutting
 Forest Fires
 surface fires (burn undergrowth and leaf litter), beneficial to
forests

crown fires (hot burning, leaps from treetop to treetop),
destructive to forests
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Major Threats
 Diseases and Insects
 accidentally or
deliberately introduced
 Eat leaves (defoliate),
flowers, buds, bore holes
in bark and woody
stems—cause extensive
damage

Easily spread from tree to
tree, hard to control
 Climate change
 trees need certain
climate conditions to
produce seeds,
germinate, or produce
fruit
 increase in drought
conditions also increases
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Deforestation and Tropical
Rainforests
 Most vulnerable ecosystems
 loss concentrated in less developed countries
 half of these forests have been lost since 1950
 estimated that these forests will be gone in the next 20-
40 years
 endemic species that are highly vulnerable to
extinction
 habitats are fragmented by roads
 slash and burn practice used to make room for
agriculture
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Rangelands (Grasslands)
 help with soil formation, erosion control, chemical
cycling, storing carbon dioxide, maintaining
biodiversity
 Rangeland--unfenced grassland used to support
grazing species
 moderate grazing healthy
 overgrazing: grass is damaged due to too much grazing
and grass not allowed to recover

causes ecosystem to be susceptible to invasive species,
drought and erosion
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Managing Forests
 Purchase sustainably harvested wood products
 Limit clear-cutting, advocate for selective
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cutting
Limit government subsidies and tax breaks,
favor replanting efforts
Educating the public about forest fires and
prevention (Smokey the Bear)
using prescribed burns to remove slash, and
other ground debris
Reduce the demand for wood products and use
them more efficiently (other source for paper)
Limit woods used as fuelwood source
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Managing Grasslands
 control number of
grazing animals
and time allowed
to graze
 rotational grazing
 eliminating
invaders with
herbicides,
mechanical
removal or burning
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National Parks and Reserves
 1,100 national parks in 120 countries
 58 national parks in the US
 Many parks threatened by invasive species, illegal activities,
limited funding, or inadequate staff
 especially in less developed countries
 13% of global land and sea set aside for reserves, but only 5%
strictly protected.
 “95% reserved for human use”
 wilderness: areas of land strictly protected from human
activities (logging, mining, motor vehicle use)
 1964 Wilderness Protection Act
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Yellowstone
National Park
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Park History
 Founded in 1872.
 America’s first National Park.
 3,468 square miles in size.
 Is the most popular park in the US, with annual
visitors topping 3 million per year, with the most visits
in the summer.
 In 1988 a devastating wildfire swept through the park,
burning upward of 36% of the vegetation.
 Result of lots of underbrush gathered in forested areas.
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Location and Climate
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Wildlife
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Popular
Attractions
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Threats
 Invasive species
 Lots of human traffic increases
the chance of invaders being
introduced
 Water Pollution
 Lots of vehicle traffic increases
oil runoff—also garbage can
accumulated in natural areas
 Overuse of hiking trails,
campsites and fishing areas
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If I were to visit…
 Old Faithful Inn
 The largest log
structure in the world!
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I would visit in
the spring…less
people and
wildflowers
blooming 
I would also make
sure to hike
Yellowstone
canyon and
Mammoth Hot
Springs trails
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