today’s agenda: (november 3, 2011) journal questions: (1) describe three types of forests. (2)...

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Today’s Agenda:(November 3, 2011)

Journal Questions:

(1) Describe three types of forests.

(2) What does El Nino refer to?

*1. Lecture I: Forests & Deforestation

2. Turn in your colorful food chain and food web project.

3. Exam next Wednesday & Thursday (Comprehensive) 11/9/11 -11/10/11

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Sustaining Ecosystems: Deforestation, Biodiversity, and Forest Management

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Important Topics for this UnitImportant Topics for this Unit

1. Forestsa. Types & Importance

2. Temperate Deforestationa. Old–growth forest, U.S. & Canada

Important Topics for this Unit 3. Tropical Deforestation

a. Clearing & degrading forests, loss of biodiversity

4. Managing Forests

a. Management practices, sustainability, reducing deforestation

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What are the major types of forests?

A. There are three general types of forests, depending primarily on climate:

1. Tropical

2. Temperate

3. Polar

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Where are more than half of the world’s forests located?

Answer: The Tropics

-Every year there is a net loss

-At least 2 million square kilometers (770,000 square miles) of forest were lost between 1990 – 1995.

(An area three times larger than the stat of Texas)

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Tropical forests account for more Tropical forests account for more than half of the world’s forestthan half of the world’s forest

© Brooks/Cole Publishing Company / ITP

Fig. 7–11

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Old Growth Forests

A. Old-growth forests are uncut forests and regenerated forests that have not been seriously disturbed for several hundred or thousands of years.

Old Growth Forests B. Examples in the U.S. are

Douglas fir, Western hemlock, Giant Sequoia, Coastal Redwoods.

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Douglas Fir Tree

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Western Hemlock Tree

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Giant Sequoia Tree

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Coastal Redwood Trees

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Old Growth Forests

c. Two-thirds of Europe’s old-growth forests are gone.

d. 95-98% of the old growth forests are gone in the United States.

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Old Growth Forests Provide:

1. Ecological niches for a multitude of wildlife species.

2. Large numbers of standing dead trees (snags) and fallen logs, which are habitats for a variety of species.

Old Growth Forests 3. Decay of this dead vegetation

returns plant nutrients to the soil and helps build fertile soil.

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Second-Growth Forests

A. Second-growth forests are stands of trees resulting from secondary ecological succession after cutting.

B. Most forests in the U.S. and other temperate areas are second-growth forests that grew back after old-growth forests were cleared for timber or to create farms.

Second-Growth Forests C. About 40% of tropical

forests are second-growth forests.

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Second-Growth Forests

d. Many are not diverse forests at all, but rather are tree farms or plantations

Second-Growth Forests

e. They are managed tracts with uniformly aged trees of one species that are harvested by clear-cutting as soon as they become commercially valuable.

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What is the Economic Importance of Forests?

Forests provide:

1. Lumbar for housing

2. Biomass for fuel-wood

3. Pulp for paper

4. Medicine (from Bark & Gums)

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Paper Usage Around the World

A. The United States has the world’s highest per capita use of paper

(About seven times the average global per capita use)

Paper Usage Around the World

B. The U.S. is the world’s largest importer of wood products

C. Other countries with very high per capita uses of paper are Japan and Germany.

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Other Uses of Forestlands1. Mining2. Grazing livestock3. Recreation

-Worldwide, about 55% of the timber cut each year is used as:

fuelwood and charcoal for heating and cooking, mostly in developing countries.

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Economic Importance of Forests

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What is the Ecological Importance of Forests?

A. Forested watersheds act as giant sponges, slowing down runoff and holding water that recharges springs, streams, and groundwater.

B. Regulate the flow of water from mountain highlands to croplands and urban areas.

What is the Ecological Importance of Forests? C. They reduce the amount of

sediment washing into streams, lakes and reservoirs by reducing soil erosion.

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(November 4, 2011) “Today’s Agenda”

Journal Question:

(1) What is the ecological importance of forests?

(2) What is the difference between an old growth forest and a second growth forest?

*Lecture II: The Influence of Forests & Tropical Forests

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Old Growth Forests in the News

On Sept. 30, a pair of 1,500-year-old giants (middle-aged in sequoia years) crashed to the ground.

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The Influence of ForestsA. Forests influence climate.

(1) 50-80% of the moisture in the air above tropical forests comes from trees via transpiration and evaporation.(2) If large areas of lush forests are cleared, the average annual precipitation drops and the region’s climate gets hotter and drier.

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The Influence of Forests

B. Forests are vital to the global carbon cycle.

(1) They take up around 90% of the carbon removed from the atmosphere as CO2

C. They also buffer against noise and absorb air pollutants.

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The Ecological Benefits from a Single Tree:

1. Oxygen Production

2. Air Purification

3. Soil Fertility

4. Erosion Control

5. Water Recycling & Humidity Control

6. Wildlife Habitat

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Ecology of Old-Growth Forests in the Northwest

A. In the Pacific Northwest it typically takes 350 years for an old-growth forest to reach its prime in terms of growth and diversity.

B. These forests have the world’s largest accumulation of dead standing trees (snags) and fallen dead trees, which decompose slowly over 200-400 years and recycle nutrients in the forest ecosystem.

Ecology of Old-Growth Forests in the Northwest

C. Without snags and fallen trees, about 29% of the wildlife in old-growth forests would disappear.

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Ecology of Old-Growth Forests in the United States

D. The survival of old-growth forests in the Pacific Northwest is also connected to the survival of the region’s salmon stocks.

(1) Economic Concerns: Annually, the $1.25 –billion sport and commercial salmon fishing industry provides jobs for 62,000 people.

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The decline of salmon stocks is due to:

A. Damming of RiversB. PollutionC. Over-fishingD. Key Factor: Excessive logging on

public lands throughout the Northwest.-Sediment deposited in streams from logging of old-growth forests and associated road building smothers spawning beds and disrupts feeding patterns of young salmon.

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The Role of the U.S. Forest Service in the loss of Old-Growth Forests

A. Environmentalists charge the U.S. Forest Service with playing a key role in destroying old-growth forests on public lands.(1) Congress allows the Forest Service to use most of the income from timber sales in national forests to supplement its budget; any financial losses it incurs are passed on to taxpayers.

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Tropical Deforestation and Loss of Biodiversity

A. Tropical forests cover about 6% of the Earth’s land area.

B. Four countries contain more than half of the world’s tropical forests:

(1) Brazil

(2) Indonesia

(3) Zaire

(4) Peru

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Types of Tropical Forests:1. Rain forests: Receive rainfall almost

daily.

2. Deciduous forests: with one or two dry seasons each year.

(1) Dry and very dry deciduous forests.

(2) Forests on hills and mountains.

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Biodiversity in Tropical ForestsA. High Biodiversity: Contain 50-

90% of the earth’s terrestrial species.

-most of the species are still unknown and unnamed.

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Tropical Forests & Economics

A. Tropical forests supply half of the world’s annual harvest of hardwood, hundreds of food products (Including coffee, tea, cocoa, spices, nuts, chocolate, and tropical fruits), and materials such as natural latex rubber, resins, dyes, and essential oils.

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Tropical Forests & Economics

B. The active ingredients for 25% of the world’s prescription drugs are derived from plants, most of which grow in tropical rain forests.

C. Of the 3,000 plants identified by the National Cancer Institute (NCI)

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Tropical Forests & EconomicsD. Tropical plants are not the only

source of important drugs.E. Recent research has discovered a

number of useful drugs in the skins of the world’s declining population of frogs, many of them in tropical forests.(1) Examples include a painkiller hundreds of times more potent than morphine, a whole new class of powerful and versatile antibiotics, and a growth hormone that helps detect cancer in humans.

Tropical Forests & Economics

F. Less than 5% of the world’s frog species has been evaluated as a source of chemical that are important to humans.

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Monday (November 7, 2011)

Today’s Agenda:

Journal Question:

(1) How are frogs and salmon effected by deforestation?

(2) Identify three environmental benefits from a single tree.

*1. Lecture: Energy Statistics, Deforestation Problems & Solutions

2. Exam on Wednesday & Thursday

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What’s up?

A. There are currently over 25,000 objects (space debris) and satellites orbiting the Earth (November 2011)

B. Monitored by the world’s most powerful radar system.

C. U.S. Space Command's largest surveillance radar

D. Eglin AFB, Florida04/21/23 46

What’s up?

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What’s up?

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What’s up? Asteroid Heading our Way

A massive chunk of black rock bigger than four city blocks is speeding toward us from outer space at more than 30,000 miles an hour.

Scientists say the asteroid won't hit us, but it will be barely more than 200,000 miles away when it passes Earth at 11:13 p.m. Tuesday (11/8/11). In cosmic terms that's really close.

Giant asteroid to get closer than the moon.

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Medicinal Frogs that Live in The Tropical Rain Forests

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Benefits from a Single Tree

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*Urban Atmospheric PollutantsA. The most serious pollutants in the urban

atmosphere are ozone, nitrogen oxides (NOx), sulfuric oxides (SOx) and particulate pollution.

B. Ground-level ozone, or smog, is created by chemical reactions between NOx and volatile organic compounds (VOCs) in the presence of sunlight.

Memorize the information of this Slide!!!

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World Energy Demands 2011

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What’s the deal with the statistics that you should know?

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Statistics that You Should KnowA. China imports more than

half of its oil.

B. China’s oil reserves are two-thirds those of the U.S.

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*Oil & Petroleum Products

The following are petroleum based products:

(1) Asphalt

(2) DDT (Pesticide)

(3) Polystyrene

(4) Nylon

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Statistic that You Should Know

C. California alone uses more gas than China, according to the California Energy Commission’s State Alternative Fuels Plan.

D. In 2007, California’s 20 billion gallon gasoline and diesel habit topped China’s total use (as well as that of Russia, India, Brazil or Germany).

Wired Magazine. “Amazing Stat: California Uses More Gas than China” July 17, 2008

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Statistics that You Should Know

E. China is the world’s largest consumer and producer of coal.

F. China relies on coal for almost 70% of its total energy supply (compared to the U.S.’s 30%). Source: (USCC.gov) 2010 Report

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Statistics that You Should KnowG. China and the U.S. together

possess 42% of the world’s coal reserves.

H. China’s Three Gorges Dam–the world’s largest hydroelectric power station—was first proposed in 1919

-National Geographic 2006

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Statistics that You Should Know

I. China is the world’s biggest producer of carbon dioxide, passing the U.S. in 2006 according to the Netherlands Environmental Assessment Agency.

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Statistics that You Should Know

J. China is home to 20 of the world’s 30 most polluted cities.

Source: The World Bank; Time Magazine “The World's Most Polluted Places” Sept. 12, 2007

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Statistics that You Should Know

K. 90% of China’s urban groundwater is contaminated.

Source: Asia Water Project; “In Deep Water: Ecological Destruction of China’s Water Resources,” 2007

L. About 300 million Chinese people in rural areas rely on unsafe drinking water.

Source: [World Bank, “Addressing China’s Water Scarcity: Recommendations for Selected Water Resource Management Issues,” 2009]

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Going Green Globally

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China leads in wind power usage as an alternative source of energy

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China is the world’s leader in wind power, after topping the U.S. in total installed wind capacity in 2010. Today, China accounts for 22% of the world’s total wind power capacity.[The Economist online “China leads the windy world” Feb. 3, 2011 ]

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China increased its renewable electric power capacity 81% in only three years (2005-2008)— exceeding the capacity of the U.S.

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China’s forest cover increased from 12% to 18% in two decades (1990-2010), through vigorous reforestation programs. The government has a national goal of reaching 23% by 2020.

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China’s Impact on Forests

A. Over the past three decades, Chinese volunteers have planted about 58.9 billion trees across the country.

B. China uses and throws away 45 billion disposable chopsticks every year, representing about 25 million trees.

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China Say’s “No” to Plastic Bags In 2008, the Chinese government

started a nationwide ban prohibiting all shops, supermarkets, and department stores from giving out free plastic bags

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Back to Deforestation and its Impact on Endangered Species

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The Extinction of Frogs

1. Frog populations have been declining worldwide at unprecedented rates, and nearly one-third of the world’s amphibian species are threatened with extinction

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The Extinction of Frogs

2. Up to 200 species have completely disappeared since 1980, and this is NOT normal: Amphibians naturally go extinct at a rate of only about one species every 250 years!!!

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The Extinction of Frogs

3. Amphibian populations are faced with an onslaught of environmental problems resulting from:

(1) Deforestation (habitat loss)

(2) Pollution

(3) Climate Change

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The Impact of Frogs1. Integral part of food webs:

(1)Tadpoles keep waterways clean by feeding on algae.

(2) Adult frogs eat large quantities of insects, including disease vectors that can transmit fatal illnesses to humans (i.e. mosquitoes/malaria).

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Fun Frog Facts

1. How many amphibian species are there?

Answer: There are 6,317 amphibian species, of which 5,576 are anurans (frogs and toads), 566 are caudates (newts and salamanders), and 175 are gymnophiones (caecilians: lack limbs).

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What’s up with the 6-legged frogs

1. The cause of the mutation is unknown, but scientists believe that it may be due to increased levels of eutrophication (an un-natural state caused by excessive amounts of fertilizer entering a body of water)

Solution: Reducing both nitrogen and phosphorous pollution.

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Possible Cures Skin secretions from at least three

species of Australian frogs (the Green Treefrog Litoria caerulea, the Southern Orange-eyed Treefrog Litoria chloris, and the Green-Eyed Treefrog Litoria genimaculata) may completely inhibit HIV, the virus that causes AIDS.

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Endangered Species Act (ESA)

A. Requires protection for any species that may be endangered or threatened and that protection takes precedence over economic concerns.

Memorize this legislation

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Migratory Bird Treaty Act

A. If the bird species is migratory between the U.S. and Canada its habitat may be protected by this act.

Memorize this legislation

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Wilderness Act

A. If the land tract is designated as wilderness or is being considered for such status, then the Wilderness Act may apply and could be used to protect the woods.

Memorize this legislation

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Mark the Date in your Calendar:

Save The Frogs Day!

April 28, 2012

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Tropical Forests & Economics

G. Most of the original strains of rice, wheat, and corn that supply more than half of the world’s population were developed from wild tropical plants.

Tropical Forests & Economics H. Botanists believe that tens

of thousands of plant strains with potential food value await discovery in tropical forests.

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Tropical Forests & Economics

I. Despite the immense potential, fewer than 1% of the estimated 125,000 flowering plant species in tropical forests (and less than 3% of all the world’s 240,000 such species) have been examined closely for possible use as human resources.

Tropical Rain Forests

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Cultural Extinction in Tropical Forests

A. About 500 years ago some 6 million tribal people lived in the Amazon Basin.

B. Today there are only about 200,000 tribal people.

C. Gold miners invaded the territory, bringing diseases and massacring tribal people for the land.

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Primary Causes of Tropical DeforestationA. Tropical deforestation results from a

number of interconnected causes, all of which are related to:(1) Population growth(2) Poverty(3) Certain governmental policies

that encourage deforestation.(4) Exports to developed countries(5) Failure to include ecological services in evaluating forest resources.

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Tropical Deforestation

A. Population growth and poverty combine to drive subsistence farmers and the landless poor to tropical forests, where they try to grow enough food to survive.

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Secondary Causes of Tropical Deforestation

1. Roads

2. Logging

3. Unsustainable peasant farming

4. Cash Crops

5. Cattle Ranching

6. Tree Plantations

7. Flooding from dams

8. Mining

9. Oil drilling

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How Serious is the Fuelwood Crisis in Developing Countries?A. In 1998 about 2.2 billion people in 63

developing countries either could not get enough fuel wood to meet their basic needs or were forced to meet their needs by using wood faster than it was being replenished.

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Problems with burning wood:

A. As burning wood (or charcoal derived from wood) to boil water becomes an unaffordable luxury, waterborne infectious diseases and death will spread.

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Other ProblemsA. Besides deforestation and

accelerated soil erosion, fuel wood scarcity has other harmful effects.

B. It places an additional burden on the rural poor, especially women and children, who often must walk long distances searching for firewood.

C. Buying fuelwood or charcoal can take 40% of a poor family’s meager income.

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Managing & Sustaining Forests:

1. Even-aged management of trees.

2. Uneven-aged management

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How are trees harvested?

1. Selective cutting

2. Shelterwood cutting

3. Seed-tree cutting

4. Clear-cutting

5. Strip cutting

6. Whole-tree cutting

7. High Grading

1. Selective Cutting

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Selective Cutting harvesting only mature trees of the desired size, type or quality. Less disruptive to the environment.

2. Shelterwood Cutting

In a shelterwood cut, mature trees are removed in two or three harvests over a period of 10 to 15 years

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3. Seed Tree Cutting In a seed tree harvest, five or more

scattered trees per acre are left in the harvested area to provide seeds for a new forest stand.

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4. Clear Cutting

A. Clear Cutting fast and cheap. Every tree is removed leaving a barren landscape. When replanted, future species are uniform (similar) and easy to clear-cut.

B. When trees are not replanted, less desirable species may grow, the exposed soil may erode and the land may be damaged.

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5. Strip Cutting The parallel lines in this satellite photo

of forestland might look pretty curious. This is a “Strip Cut”

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6. Whole Tree Cutting also called Single Tree Cutting Single-tree selection, the most

intensive harvesting method that moves individual trees ready for harvest.

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7. High GradingA. Cutting the best trees

(those of highest value) and leaving the low value, often diseased or malformed trees.

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Threats to ForestsA. Acid Precipitation caused by

emissions from industrial areas, harms the canopy as well as the soil.

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Threats to Forests B. Forest Fires: 48% caused by

lightning, fairly remote areas, 52% caused by people near settled areas.

Before After

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Prescribed Burning

A. Prescribed burning is a forest management practice that benefits certain forests by reducing the amount of leaves, branches and dead trees accumulated on the forest floor that could fuel a wildfire.

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Prescribed Burning

B. In addition to helping control the spread of wildfire, removal of this "litter layer" also promotes the growth of new forage and succulent plants, which are important sources of food for many wildlife species including rabbits and deer.

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Forrest Succession

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Solutions: Sustainable Forestry/Management1. Recycling more paper to reduce

the harvest of pulpwood trees, using fibers from fast-growing plants to make tree-free paper, and reducing wood waste.

2. Growing more timber on long rotations, generally about 100-200 years, depending on species and soil quality.

Forests Paper

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Paper Recycling

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Solutions: Sustainable Forestry/Management3. Producing selective cutting of individual

trees or small groups of most tree species.

4. Minimizing fragmentation of remaining larger blocks of forest.

5. Using road building and logging methods that minimize soil erosion and compaction.

6. Practicing strip cutting instead of conventional clear-cutting.

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Solutions: Sustainable Forestry/Management7. Leaving most standing dead trees

(snags) and fallen timber to maintain diverse wildlife habitats and to be recycled nutrients.

*Protecting Wooded Areas

(1) Preserve the most sensitive area; develop in the least sensitive area.

(2) Develop an ordinance requiring tree preservation.

(3) Request a scientific investigation into the viability of the species which will then help to direct development.

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*Overgrazing of public land by privately owned livestock is an example of ..

Tragedy of the Commons

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*Compared with people in developing countries, people in industrialized countries are most likely to eat

Beef

Where’s the beef?

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A Possible Essay Prompt

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Future Topics:

Comprehensive AP Exam next Class Deforestation (completed) Deforestation, Population, Ethics,

Urbanization, Nuclear Power.

-China (Population film)

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