Read two articles and write 3 pages essay including few deatils from the chapters which are attached below.

Forests_Chapter12.pdf

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Lecture Outlines

ENVIRONMENT the science behind the stories

Chapter 12

Forests, Forest Management, and Protected Areas

Lecture objectives  Summarize the ecological and economic

contributions of forests.  Outline the history and current scale of

deforestation.  Assess dynamics of timber management.  Discuss forest management in relation to fire, pests,

and climate change, and evaluate sustainable forestry certification.

 Name federal land management agencies and the lands they manage.

 Discuss types of parks and protected areas and evaluate issues involved in their design.

Certified Sustainable Paper in Your Textbook  Each stage of production of your textbook, including

harvesting and transporting the trees, processing at the pulp mill and paper production, has followed a sustainable management plan.

 Inspectors from the Forest Stewardship Council, an independent third-party organization, have established many criteria that must be met for FSC certification.

 FSC-certified operations must:  Protect rare species and sensitive habitats.  Safeguard water sources.  Control erosion.  Minimize pesticide use.  Maintain forest diversity and its ability to regenerate

after harvesting.

Forest Ecosystems and Forest Resources  A forest is any ecosystem with a high density of

trees.  Forest biomes include boreal forest, tropical

rainforest, temperature deciduous forests, temperate rainforests, and tropical dry forests.

 Within each forest biome, differences in soil and climate will alter the community.

 Forest types are classifications of forests based on their predominant tree species.  Altogether, forests cover 31% of Earth’s land surface.

Forests are ecologically complex  Forests are structurally complex, with each level

providing niches for many different organisms.  The canopy is the upper level of leaves and

branches in the treetops.

 The subcanopy is the middle portion of the forest, found beneath the tree crowns of the canopy.

 The shaded lower level consisting of shrubs and small trees is the understory.

 The forest floor contains groundcover plants.

 Dead and dying trees, called snags, are homes for insects, which in turn provide food sources for birds.

 Fallen trees create openings called treefall gaps, areas where sunlight encourages the growth of early successional plants.

Forests provide ecosystem services  Tree roots stabilize soil and

draw up minerals from deep soil layers.

 Leaves and leaf litter slow runoff by intercepting water, increasing water infiltration into soil and aquifers.

 Forest plants filter pollution, take in carbon dioxide, and produce oxygen that we breathe.

 Forests also provide cultural, aesthetic, and recreation values to people.

Forests provide us valuable resources  Forests also contain plants we use for medicines

and dyes, animals, plants and fungi for food, and wood from the trees themselves.

 Industrial harvesting has increased our ability to extract timber, with most of it coming from countries with boreal forests like Canada and Russia or rainforests such as Brazil or Indonesia.

Forest Loss  Deforestation is the clearing of forests more quickly

than they can regrow.  Deforestation leads to biodiversity loss, soil

degradation, and desertification, as well as contributing to climate change.

 Satellite analysis conducted by the Food and Agriculture Organization (FAO) of the United Nations concluded that we are eliminating 7.6 million hectares of forest each year.  Accounting for regrowth, that is an annual net loss of

3.3 million hectares.

We deforested much of North America  Heavy deforestation through the mid-1800s in North

America has resulted in very little primary forest being left behind.  Primary forest is natural forest left uncut by people.

 Most of the trees in today’s forests are ones that have sprouted and grown to partial maturity since the old-growth trees were cut.  These forests are called secondary forests, and may

have a very different species composition, structure, and nutrient balance.

Forests today are cleared most rapidly in developing nations  Uncut primary forests still remain in many

developing countries, but are being harvested much more rapidly due to powerful industrial technologies.  The deforestation is spurred by a desire to expand

human settlements, boost economic growth, and provide fuelwood for heating and cooking needs.

 In contrast, parts of Europe and the United States are gaining forest as they recover from past deforestation.

[Insert Figure 12.6(b), p. 306, 6e]

 Brazil is a good example of this, as it has lost forests rapidly to expanding soybean farming and cattle ranching.

[Insert Figure 12.7, p. 307, 6e]

 Developing nations may allow their timber to be extracted by large multinational corporations, who pay them fees called concessions.  The timber is then exported to wealthier nations.

 Concessions often lead to short-term economic benefits, but many environmental consequences for the developing nations.

 In Southeast Asia, swaths of tropical rainforest are being cut to establish palm oil plantations.  Palm oil is used as

a biofuel and is also found in many processed foods.

Forest loss worsens climate change  The world’s forests store an estimated 296 billion

metric tons of carbon in the living tissues of trees and other plants.  When forests are cut and burned or decomposed,

carbon dioxide is released into the atmosphere and less vegetation remains to soak it back up.

Solutions are emerging  Conservations are pursuing community-based

stewardship projects that empower local people to act as stewards for their forests.

 Other organizations provide conservation concessions, or payments to countries to preserve forests instead of harvesting them.

 This idea is expanding under an international program called Reducing Emissions from Deforestation and Forest Degradation (REDD+).  Developing nations receive conservation

concessions, while developed countries receive carbon emissions offset credits.

Review Questions 1. What type of forest is more likely to be found in

historically clear-cut areas in North America and Europe? a. Primary b. Secondary c. An even mixture of primary and secondary forests

Review Questions 2. What layer of a forest contains most of the leaves,

fruit, and is the primary site for photosynthesis? a. Canopy b. Subcanopy c. Understory d. Forest floor

Review Questions 3. Payments given to countries in exchange for timber

rights are called a. snags. b. concessions. c. conservation concessions. d. carbon offsets.

Forest Management  Forestry is the practice of managing society’s

demand for forests against maintaining them as ecosystems.  Timber is renewable, as long as it is not exploited too

rapidly.  Resource management describes the overall

strategy of managing and regulating the harvest of renewable resources.

Resource managers follow several strategies  Resources managers try to determine the maximum

sustainable yield, allowing them to achieve the greatest amount of resource extraction without depleting the resource.  This usually means

a harvest at about the middle of the logistic growth curve.  The downside is that

the population is limited to about half its normal size.

 An alternative system is ecosystem-based management, where managers try to minimize impacts on the ecosystem and its processes.  Protect certain areas of the forest.  Restore ecologically important habitats.  Consider patterns at the landscape level.

 This system is difficult to implement because ecosystems are so complex that scientists often disagree on how to set it up.

 Adaptive management involves testing different approaches and trying to improve methods over time.

Fear of a “timber famine” inspired national forests  The United States established and began managing

the national forest as high rates of deforestation gave rise to fears of a national “timber famine.”

We extract timber from private and public lands  Today, almost 90% of

the timber harvesting in the United States takes place on private land.  Timber companies

pursue maximum sustainable yield, to maximize yearly profits.

 The Forest Service sells timber below its own costs, creating a situation where taxpayers subsidize private timber harvesting on public land.  Only about 2% of U.S. Forest acreage is harvested

for timber each year.  Overall, timber harvesting has been stable in

developed countries in the past half-century, but has doubled in developing countries.

Plantation forestry has grown  Today’s timber industry focuses on monocultures of

fast-growing trees that are all planted at the same time.  This is called

even-aged, since the trees are all the same age.

 Even-aged stands lack the biodiversity and habitat offerings of regular forests, and are highly vulnerable to pest insects.

 Uneven-aged stands create a mix of ages (and species), which creates greater structural diversity, more habitats, and is generally more similar to what a national forest would look like.

We harvest timber by several methods  The simplest method of

harvesting is clear- cutting, where all the trees are cut at once.  This increases erosion

and alters microclimates due to increased sunlight penetration.

 Other approaches include:  The seed-tree approach, where some seed-

producing trees are left to reseed the harvested area.  The shelterwood approach leaves some mature

trees behind to shelter growing seedlings.  Selection systems maintain uneven-aged stands by

only removing some trees.  Selection systems are the most expensive and pose

more safety risks to loggers.

Forest management has evolved over time  For the past half-century, the U.S. Forest Service

has followed the multiple use policy, meaning that forests are to be managed for recreation, wildlife habitat, mineral extraction, and other uses in addition to timber.

 In 1976, the U.S. Congress passed the National Forest Management Act, which required the Forest Service to draw up renewable resource management plans for each national forest.

 Since the law was passed, programs to manage wildlife, non-game animals and endangered species have been developed.  Nesting trees for an

endangered bird, for example, may be marked with bands of paint.

 A set of approaches called new forestry tries to make harvesting mimic natural disturbances, such as a windstorm.

 In 2001, President Bill Clinton issued an executive order called the roadless rule that placed about a third of national forests off-limits to road construction.  In 2005, the rule was repealed by President George

W. Bush, allowing states to decide for themselves how to manage national forests within their boundaries.  Most of the roadless rule policy was then reinstated

by President Barack Obama.

Fire can help or hurt forests  For much of its existence, the Forest Service

suppressed fire whenever it broke out.  Scientists now know that

fire is an important part of forest ecology.  Fire suppression has

also led to an increase in large, catastrophic fires.

 More residential development along forested land, the wildland-urban interface, has placed more homes in fire-prone situations.

 To reduce fuel loads, protect property, and improve forest conditions, land management areas will now use intentionally set, low-intensity fires called prescribed burns.

 Major fires in California in 2003 led to the passage of the Healthy Forests Restoration Act.  This act promoted prescribed burns, physical removal

of underbrush and dead trees, and the practice of salvage logging where fallen trees are removed after a large storm.

Climate change and pest outbreaks are altering forests  Global climate change has brought warmer, drier

weather to the American West, worsening fire risks.  Pine bark beetle outbreaks have worsened, killing

billions of conifer trees, leaving them as fodder for fire.

[Insert Figure 12.19(a), p. 315, 6e]

 Pine bark beetle outbreaks have worsened for two reasons:  Even-aged plantation forests have high numbers of

trees that are at the perfect age for beetle infestation.  Milder winters allow

the beetles to overwinter further north than usual, and warmer summers increase their activity and feeding rates.

Sustainable forestry is gaining ground  Organizations such as the Forest Stewardship

Council (FSC) now examine practices of timber companies and rate them.

 Sustainable forest certification is granted to companies whose methods are judged to be sustainable.

Parks and Protected Areas  The United States created the world’s first national

parks to preserve the American West for nature appreciation and recreation.

 The Antiquities Act of 1906 gave the president authority to declare selected public lands as national monuments.

 The National Park Service was created in 1916 to administer the 408 total parks and monuments.  The parks receive over 280 million reported recreation

visits per year.

 Another classification of protected area is the national wildlife refuge, which are meant to be havens for wildlife.  The U.S. Fish and

Wildlife Service administers the refuges.  Non-commercial

hunting, fishing, photography, and environmental education are all encouraged at refuges.

Wilderness areas are established on federal lands  In 1964, the U.S. Congress passed the Wilderness

Act, allowing some federal areas to be designated wilderness areas.  These areas are

off-limits to development, but open to hiking and other low-impact public recreation.

Not everyone supports setting land aside  When some of the western states came into

existence, the federal government retained control over much of their acreage.  Idaho, Oregon, and Utah control less than half of their

own land.  Some state governments want to gain control over

these lands, and allow them to be used for resource extraction.

 Parks may also be opposed by indigenous people.  Native Americans, for example, oppose rock climbing

at Devil’s Tower National Monument in Wyoming.

Many agencies and groups protect land  Each U.S. state has agencies that manage public

lands, as do counties and municipalities.  Nearly 7,000 state parks are found across the United

States.  Private nonprofit groups may also purchase land for

preservation, creating land trusts.  Examples include California’s Big Sur, Jackson Hole

in Wyoming, and Maine’s Mount Desert Island.

Parks and reserves are increasing internationally  Worldwide area in protected parks and reserves has

increased nearly sevenfold since 1970.  Parks in developing countries often do not have the

funding needed to manage them and protect them from poaching.

 The United Nations has established protected areas called biosphere reserves that have exceptional levels of biodiversity and benefit local people.  Biosphere reserves contain three zones, each of

which has different limits on how the land can be used.

 The U.N. also designates world heritage sites, which have special natural or cultural values and span the borders of multiple countries.  One example is a mountain gorilla reserve that

integrates parklands from Rwanda, Uganda, and the Democratic Republic of Congo.

Economic incentives can help preserve land  Conservation organizations may offer a debt-for-

nature swap, where the organization raises money to pay off a developing nation’s international debt in exchange for setting aside land as reserves.  The United States forgave $30 million in debt to

Indonesia to preserve forested areas that are home to the Sumatran Tiger.

Habitat fragmentation makes preserves more vital  Expanding agriculture, cities, highways, and logging

can all divide up large areas of habitat into small, disconnected ones.

 When forests are fragmented, large species that need large areas of habitat may disappear.

 Other species may experience edge effects, where the conditions along a fragment’s edge differ from the conditions in the interior.  Birds, like the wood thrush,

that live near the edges of habitats, may be attacked by predators and parasites that favor open areas.

Insights from islands warn us of habitat fragmentation  The island biogeography theory explains how the

number of species on an island is the result of a balance between immigration of new species and others lost through extirpation.  The theory predicts

an island’s species richness based on its size and distance from the mainland.

 The farther an island is from a continent, the fewer species tend to colonize it.

 Larger islands have higher immigration rates.  Larger islands have lower extinction rates.

[Insert Figure 12.26, p. 323, 6e]

Reserve design has consequences for biodiversity  With fragmentation in mind, conservationists have

debated whether it is better to make reserves large in size and few in number, or small in size and many in number.  This is called the SLOSS (single large or several

small) debate.  Large species that roam great distances benefit the

most from larger reserves.  Smaller organisms like insects thrive in smaller areas

and are better helped by having a wide variety of habitats protected.

Review Questions 4. Which of these activities would NOT be allowed in

a U.S. national park such as Yellowstone? a. Overnight camping b. Hiking c. Fishing d. Logging

Review Questions 5. What is a biosphere reserve?

a. Land managed by a country for sustainable resource extraction

b. An area set aside by a country for wildlife protection c. A United Nations-managed area of high biodiversity

that combines preservation with sustainable development

d. A forested area that only allows hunting but not timber extraction

Review Questions 6. Which of these island characteristics would be

TRUE according to the island biogeography theory? a. Smaller islands have lower extinction rates. b. Larger islands have lower rates of species

immigration. c. Islands close to continents are colonized by new

species more easily. d. Island distance is not a variable that affects species

richness.

Slide Number 1
Lecture objectives
Certified Sustainable Paper in Your Textbook
Slide Number 4
Forest Ecosystems and Forest Resources
Slide Number 6
Forests are ecologically complex
Slide Number 8
Slide Number 9
Forests provide ecosystem services
Slide Number 11
Forests provide us valuable resources
Forest Loss
We deforested much of North America
Slide Number 15
Forests today are cleared most rapidly in developing nations
Slide Number 17
Slide Number 18
Slide Number 19
Slide Number 20
Forest loss worsens climate change
Solutions are emerging
Review Questions
Review Questions
Review Questions
Forest Management
Resource managers follow several strategies
Slide Number 28
Fear of a “timber famine” inspired national forests
We extract timber from private and public lands
Slide Number 31
Plantation forestry has grown
Slide Number 33
We harvest timber by several methods
Slide Number 35
Slide Number 36
Forest management has evolved over time
Slide Number 38
Slide Number 39
Fire can help or hurt forests
Slide Number 41
Slide Number 42
Slide Number 43
Climate change and pest outbreaks are altering forests
Slide Number 45
Sustainable forestry is gaining ground
Parks and Protected Areas
Slide Number 48
Slide Number 49
Wilderness areas are established on federal lands
Not everyone supports setting land aside
Many agencies and groups protect land
Parks and reserves are increasing internationally
Slide Number 54
Slide Number 55
Economic incentives can help preserve land
Habitat fragmentation makes preserves more vital
Slide Number 58
Insights from islands warn us of habitat fragmentation
Slide Number 60
Reserve design has consequences for biodiversity
Review Questions
Review Questions
Review Questions