Apes-ch-10x 2nd sem. - TeacherWeb

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Apes ch 10

Key Concepts

Human land use

Types and uses of US public lands

Forests and forest management

Implications of deforestation

Management of parks

Establishment and management of nature preserves

Importance of ecological restoration

Core Case Study: Reintroducing

Gray Wolves to Yellowstone

Around 1800

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 no longer protected

Factors Decrea
sing Biodiversity

Extreme environmental conditions

Large environmental disturbance

Intense environmental stress

Severe shortages of resources

Nonnative species introduction

Geographic isolation

Importance of Biodiversity

Intrinsic value: Biodiversity tha
t exists regardless of their use to humans

Instrumental value: Value based on their usefulness to humans (use value & nonuse value)

Nonuse value:

Existence value

Aesthetic value

Bequest value


Conservation Biology

Conservation Biology: Multidisciplinary
science with the goal to slow down the rate at which we are
destroying and degrading the earth’s biodiversity

“Hot spots”:Most endangered and species
-
rich ecosystems that ate in need of emergency action

Rapid Assessment Teams

Based on Leopold’s ethics

Bio
informatics

Bioinformatics: Applied science of managing, analyzing, and communicating biological information

Bioinformatics tools:

High
-
resolution digitized images

Computer databases of images, DNA sequences for identifying bacteria and microorganisms, bi
ological
information on species and ecosystems

Information is readily available on internet

Types of Forests

Old
-
growth (frontier) forests: Uncut or regenerated forest that has not been disturbed by humans for
several hundred years (
36% of world’s forest
s)


Second
-
growth forests: A strand of trees resulting from secondary succession (
60% of world’s forests)


Tree farms/plantation: Managed tract with uniformly aged trees of one species that are harvested by
clear
-
cutting then replanted (
4% of world’s fores
ts
)

Forest Management

Rotation cycle: Cycle of cutting and regrowth of a monoculture tree plantation

Even
-
aged management: All trees in a stand are about the same age and size

Uneven
-
aged management: Variety of tree species of different ages and sizes; gr
eater biodiversity

Forests Provide Important Economic

and Ecological Services

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

Habita
ts

Forests Provide Important Economic

and Ecological Services

Wood for fuel

Lumber

Pulp to make paper

Mining

Livestock grazing

Recreation

Employment

Science Focus: Putting a Price Tag on Nature’s Ecological Services

Forests valued for ecological
services

Nutrient cycling

Climate regulation

Erosion control

Waste treatment

Recreation

Raw materials

$4.7 Trillion per year

Roads Lead to Forest Degradation

Increased erosion and runoff

Habitat fragmentation

Pathways for exotic species

Accessibility to h
umans

Harvesting Trees

Selective cutting: Intermediate
-
aged or mature trees in an uneven
-
aged forest are cut singly or in
small groups

High
-
grading: Removal of the largest and best specimens

Shelterwood cutting: Removal of all of the mature trees in 2 to

3 cuttings

Seed
-
tree cutting: Removal of most of the trees but leave a few seed
-
producing trees to regenerate
the forest

Harvesting Trees

Clear
-
cutting: Removal of all the trees in a given area

Strip cutting: Clear
-
cutting in narrow strips along contour

lines; After the strips regenerate in a few
years the loggers cut a new strip

Deforestation: A temporary or permanent removal of large expanses of forest for agriculture or other
uses

Sustainable Forestry

Longer rotations

Selective or strip cutting

Minimize fragmentation

Improved road building techniques

Certify sustainable grown


Certifying Sustainable Timber

Must be done by outside evaluators

Scientific Certification System (SCS)

Forest Stewardship Council (FSC)

Rainforest Alliance’s Smart Wood Pr
ogram

World Wildlife Fund (WWF)

Mitsubishi, Home Depot, Lowes, Anderson have all agreed to sell only certified wood

Read about Butterfly on page 206! Some people care

Fire, Insects, and Climate Change Can Threaten Forest Ecosystems

Surface fires


Usually

burn leaf litter and undergrowth

May provide food in the form of vegetation that sprouts after fire

Crown fires

Extremely hot: burns whole trees

Kill wildlife

Increase soil erosion

Fire, Insects, and Climate Change Can Threaten Forest Ecosystems

Introdu
ction 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

Insect and Pathogen

Sudden oak death

White pine blister rust

Pine
shoot beetle

Beech bark disease

Hemlock woolly adelgid

Fire

Forest Fire Prevention

“Smokey Bear” (bad)

Increased logging in the 1980’s (slash) (worse)

“Healthy Forest Initiative” (worst)

Prescribed Burns & thinning

Buffer zones and building standards

W
e Have Cut Down Almost Half

of the World’s Forests

Deforestation


Tropical forests

Especially in Latin America, Indonesia, and Africa

Boreal forests

Especially in Alaska, Canada, Scandinavia, and Russia

Case Study: Many Cleared Forests in the United Stat
es Have Grown Back

Forests of the eastern United States decimated between 1620 and 1920

Grown back naturally through secondary ecological succession

Biologically simplified tree plantations reduce biodiversity

Tropical Forests are Disappearing Rapidly

Ma
jority of loss since 1950

Brazil and Indonesia tropical forest loss

Role of deforestation in species’ extinction

Case Study: Deforestation and the Fuelwood Crisis

Possible solutions

Establish small plantations of fast
-
growing fuelwood trees and shrubs

Burn wood more efficiently

Solar or wind
-
generated electricity

Haiti: ecological disaster

South Korea: model for successful reforestation

Governments and Individuals Can Act

to Reduce Tropical Deforestation

Reduce fuelwood demand

Practice small
-
scale sus
tainable agriculture and forestry in tropical forest

Debt
-
for
-
nature swaps

Conservation concessions

Use gentler logging methods

Buy certified lumber and wood products

Tropical Deforestation: Consequences

Rapid and increasing

In 1970 only 1% of the Amazon

basin was deforested; 2003 almost 29%

Loss of biodiversity

Loss of resources (
e.g
., medicines)

Contributes to global warming

Solutions

Improve efficiency of wood use (60% is wasted)

Tree
-
free paper products

Kenaf (“kuh
-
NAHF”) needs less herbicide, gr
ows faster, and takes less energy and chemicals to turn into
paper pulp

Change logging town economy to a more recreation based economy

Reducing Tropical Deforestation

Encourage protection of large tracts

Sustainable tropical agriculture

Debt
-
for
-
nature
swaps

Reduce illegal cutting

Reducing poverty and population growth


Some Rangelands Are Overgrazed

Important ecological services of grasslands

Soil formation

Erosion control

Nutrient cycling

Storage of atmospheric carbon dioxide in biomass

Maintenance of

diversity

Some Rangelands are Overgrazed

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 stor
y

We Can Manage Rangelands More Sustainably

Rotational grazing

Suppress growth of invasive species

Herbicides

Mechanical removal

Controlled burning

Controlled short
-
term trampling

Case Study: Grazing and Urban Development the American West

American sout
hwest: 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

Types of US Public Lands

Multiple
-
use lands
: National Forests; National Resource Lands

Moderately
-
restricted use lands
: National Wildlife Refuges

Restricted
-
use lands
: National Park System; National Wilderness Preservation System


US Public Lands

35% o
f the U.S. is public land,73% of public land is in Alaska, 22% is in western states

National Forest system: Managed by U.S. Forest System; 155 forests & 22 grasslands

Logging, mining, livestock grazing, oil & gas extraction, recreation, hunting, fishing,
conservation of
watershed, soil and wildlife

National Resource Lands: Managed by the Bureau of Land Management (BLM)

Mining, oil and gas extraction, and livestock grazing


US Public Lands

National Wildlife Refuges: Managed by U.S. Fish and Wildlife
Service (USFWS), protects habitats and
breeding areas for waterfowl and big game

National Park System: Managed by the Nation Park Service (NPS); 56 major parks, 331 national
recreation areas, monuments, battlefields, historic sites, parkways, trails, river
s, seashores and
lakesides

National Wilderness Preservation System: Most restricted, 660 roadless areas

Managing US Public Land

Protecting biodiversity and ecological function should be primary goal

No subsidies or tax breaks for use

Public should get
f
air
compensation for extraction of any resources

Users held responsible for any environmental damage they cause

Case Study: Stresses on U.S.

Public Parks

58 Major national parks in the U.S.

Biggest problem may be popularity

Noise

Congestion

Pollution

D
amage or destruction to vegetation and wildlife

Repairs needed to trails and buildings

Science Focus: Effects of Reintroducing the Gray Wolf to Yellowstone National Park

Gray wolves prey on elk and push them to a higher elevation

Regrowth

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

Logging in U.S. National Forests

Provides local jobs

Provides only 4%
of timber

Increases environmental damage

Hinders recreation income

Managing and Sustaining National Parks

Inadequate protection

Often too small to sustain biodiversity

Invasions by nonnative species

Too many human visitors

Traffic jams and air pollution

Better pay for park staff

Establishing, Designing, and Managing Nature Reserves

Include moderate to large tracts of land

Involve government, private sector and citizens

Biosphere reserves

Adaptive ecosystem management

Protect most important areas (“hot sp
ots”)

Wilderness areas

Nature Reserves Occupy Only a Small Part of the Earth’s Land

Conservationists’ goal: protect 20% of the earth’s land

Cooperation between government and private groups

Nature Conservancy

Eco
-
philanthropists

Developers and resource
extractors opposition

Designing and Connecting Nature Reserves

Large versus small reserves

The buffer zone concept

United Nations: 529 biosphere reserves in 105 countries

Habitat corridors between isolated reserves

Advantages

Disadvantages

Case Study: Cos
ta Rica

A Global Conservation Leader

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 megareserves

Designed to sustain around 80% of Costa Rica’s biodiv
ersity

Case Study: Controversy over Wilderness Protection in the United States

Wilderness Act of 1964

How much of the United States is protected land?

Roadless Rule

2005: end of roadless areas within the national forest system

Ecological Restoration

Rest
oration: Returning an Area to its natural state

Rehabilitation: Turning a degraded ecosystem back to a functional ecosystem

Remediation: Cleaning up chemical contamination by physical or chemical means

Replacement: Replacing a degraded ecosystem with anoth
er type

Creating artificial ecosystems: Artificial reefs

Ecological Restoration: Basic Principles

Mimic nature

Recreate lost niches

Rely on pioneer species

Control nonnative species

Reconnect small patches

We Can Use a Four
-
Point Strategy

to Protect Ecosystems

Map global ecosystems; identify species

Locate and protect most endangered species

Restore degraded ecosystems

Development must be biodiversity
-
friendly

Are new laws needed?

Protecting Global Biodiversity Hot Spots Is an Urgent Prio
rity

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

Protec
ting Ecosystem Services Is

Also an Urgent Priority

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

We Can Sha
re Areas We Dominate With Other Species

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

Belize and the black howler monkeys

Pro
tect vital insect pollinators

Bluebird protection with special housing boxes

Berlin, Germany: rooftop gardens

San Francisco: Golden Gate Park

Case Study: The Blackfoot Challenge

Reconciliation Ecology in Action

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