Sustaining Terrestrial Biodiversity: The Ecosystem Approach

Chapter 10

America’s “crown jewel”

Parks are diverse and come in many different sizes

Purchases have been made by government or private individuals/companies

Yellowstone NP was the first (1872)

National Parks System

John Muir – S16 & S17

Henry David Thoreau

Aldo Leopold

President Teddy Roosevelt

Important People

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.

Clubs & Organizations

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) –◦ responsible for identification and listing of,◦ and monitoring the import of threatened and endangered

species.◦ Responsible for administering the Endangered Species Act

National Wildlife Refuges – areas that have been set aside for the protection of threatened or endangered species.

Services

1. Air, noise and water pollution

2. Invasion of non-native species

3. Tourism – high number of park visitors can degrade natural areas

4. LACK OF FUNDING

5. Pressure from developers, lumber and mining companies

Threatened by

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)

Fragmented Habitats

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)

Legislation and Policy

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

National Wild & Scenic River System

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

Core Case Study: Reintroducing Gray Wolves to Yellowstone

Controversy in Yellowstone

Environmentalists Farmers, Hunters, Loggers and Miners

Keystone species

Cull herds of bison, elk and caribou

Keep the coyote population down

Provide meat for scavengers

Leave the park and attack cattle and sheep

Kill big-game animals

Mining and logging companies feared having to halt operations on wolf-populated federal land

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.

What Are the Major Threats to Forest Ecosystems?

Statistics

Wilderness Forests

About 5% of Earth’s remaining areas are protected either strictly or partially by law.

About 20% of Earth’s land area is needed to adequately preserve biodiversity.

Forests cover about 30% of the United States.

About 40% of the forests in the US are protected.

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

Forests Vary in Their Make-Up, Age , Origins

Rotation Cycle of Cutting and Regrowth of a Monoculture Tree Plantation

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 Provide Important Economic andEcological Services

Forests valued for ecological services◦Nutrient cycling◦Climate regulation◦Erosion control◦Waste treatment◦Recreation◦Raw materials

$4.7 Trillion per year

Putting a Price Tag on Nature’s Ecological Services

Estimated Annual Global Economic Values of Ecological Services Provided by Forests

Increased erosion Sediment runoff into waterways Habitat fragmentation Loss of biodiversity Invasion by

◦ Nonnative pests◦ Disease◦ Wildlife species

Unsustainable Logging is a Major Threat to Forest Ecosystems

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

Major Tree Harvesting Methods

Major Tree Harvesting Methods (cont.)

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 clear-

cutting• Involves clear-cutting

a narrow corridor of land, allowing a few years for regeneration, then logging another strip above the previous strip(s).

Fig. 10-6a, p. 219

Stepped Art

(b) Clear-cutting

Muddy stream

UncutCut 1 year ago

Dirt road

Cut 3–10 years ago

Uncut

Clear stream

(a) Selective cutting

(c) Strip cutting

Clear stream

Clear-Cut Logging in Washington State, U.S.

Advantages and Disadvantages of Clear-Cutting Forests

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

Surface fires

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

◦ 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

We Can Improve the Management of Forest Fires

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

Insects, and Climate Change Can Threaten Forest Ecosystems

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

Tropical Rainforests

Deforestation◦Tropical forests Especially in Latin

America (Brazil), Indonesia, and Africa

◦Boreal forests Especially in Alaska,

Canada, Scandinavia, and Russia

We Have Cut Down Almost Half of the World’s Forests (40%)

Deforestation in Thailand

Natural Capital Degradation: Harmful Environmental Effects of Deforestation

Forests of the eastern United States decimated between 1620 and 1920

Grown back naturally through secondary ecological succession

Biologically simplified tree plantations reduce biodiversity

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

Majority of loss since 1950

Brazil and Indonesia tropical forest loss

Role of deforestation in species’ extinction

Tropical Forests are Disappearing Rapidly

Satellite Images of Amazon Deforestation between 1975 and 2001

Fig. 10-15, p. 225

NATURAL CAPITAL

DEGRADATION

Major Causes of the Destruction and Degradation of Tropical ForestsBasic Causes Secondary Causes• Not valuing ecological services • Roads • Cattle ranching• Crop and timber exports • Fires • Logging• Government policies • Settler farming • Tree plantations

• Poverty • Cash crops

• Population growthCattle ranching

Tree plantations

Logging

Cash crops

Settler farming

FiresRoads

Population growth

Poverty

Oil extraction

Massive foreign debt

Some Major Factors for Destruction

Natural Capital Degradation: Large Areas of Brazil’s Amazon Basin Are Burned

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.

How Should We Manage and Sustain Forests?

Solution: Sustainable Forestry

Collins Pine ◦Owns and manages protective timberland

Forest Stewardship Council◦Nonprofit ◦Developed list of environmentally sound practices◦Certifies timber and products

Science Focus: Certifying Sustainably Grown Timber

Improve the efficiency of wood use◦ Reduce construction

waste◦ Reduce the amount of

junk mail◦ Use laminated boards

Make tree-free paper◦Kenaf◦Hemp

We Can Reduce the Demand for Harvested Trees

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

Haiti: ecological disaster South Korea: model for successful reforestation

Case Study: Deforestation and the Fuelwood Crisis

Reduce fuelwood demand

Practice small-scale sustainable agriculture and forestry in

tropical forest

Debt-for-nature swaps

Conservation concessions

Use gentler logging methods

Buy certified lumber and wood products

Governments Can Act to ReduceTropical Deforestation

Green Belt Movement: 1977◦Self-help group of women in Kenya◦Success of tree planting

Nobel Peace Prize: 2004

Individuals Matter: Wangari Maathai and Kenya’s Green Belt Movement

Fig. 10-19, p. 231

SOLUTIONSSustaining Tropical Forests

Prevention Restoration

Protect the most diverse and endangered areas

Encourage regrowth through secondary successionEducate settlers about

sustainable agriculture and forestry

Protect forests with debt-for-nature swaps and conservation concessions

Rehabilitate degraded areas

Subsidize only sustainable forest use

Certify sustainably grown timber

Reduce poverty

Concentrate farming and ranching in already-cleared areasSlow population growth

We can sustain the productivity of grasslands by controlling the number and distribution of grazing livestock and restoring degraded grasslands.

How Should We Manage and Sustain Grasslands?

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 story

Results of Overgrazing

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

We Can Manage Rangelands More Sustainably

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

Case Study: Grazing and Urban Development the American West

Sustaining biodiversity will require protecting much more of the earth’s remaining undisturbed land area as parks and nature reserves.

How Should We Manage and Sustain Parks and Natural Reserves?

Worldwide: 1100 major national parks

Parks in developing countries ◦Greatest

biodiversity◦1% protected

against Illegal animal

poaching Illegal logging

and mining

National Parks Face Many Environmental Threats

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

Case Study: Stresses on U.S. Public Parks

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

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

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

Cooperation between government and private groups

Nature Conservancy Eco-philanthropists Developers and resource extractors opposition

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

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

Designing and Connecting Natural Reserves

Fig. 10-24, p. 237

Biosphere Reserve

Core area

Research station

Visitor education center

Buffer zone 1

Human settlements Buffer zone 2

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

Case Study: Costa Rica—A Global Conservation Leader

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

Case Study: Controversy over Wilderness Protection in the United States

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.

What is the Ecosystem Approach to Sustaining Biodiversity ?

Map global ecosystems; identify species Locate and protect most endangered species Restore degraded ecosystems Development must be biodiversity-friendly Are new laws needed?

We Can Use a Four-Point Strategy to Protect Ecosystems

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.

Hot Spots

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

Protecting Global Biodiversity Hot Spots Is an Urgent Priority

Endangered Natural Capital: 34

Active Figure: Biodiversity hot spots

Fig. 10-27, p. 241

Top Six Hotspots1 Hawaii2 San Francisco Bay area3 Southern Appalachians

4 Death Valley5 Southern California6 Florida Panhandle

Concentration of rare species

Moderate HighLow

Biodiversity Hotspots in the US

Biodiversity Hotspots in the U.S.

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

A Biodiversity Hot Spot in East Africa

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

Protecting Ecosystem Services Is Also an Urgent Priority

Study how natural ecosystems recover◦ 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

We Can Rehabilitate and Restore Ecosystems That We Have Damaged

Guanacaste National Park restoration project◦Relinked to adjacent rain forest◦Bring in cattle and horses – aid in seed dispersal◦Local residents – actively involved

Science Focus: Ecological Restoration of a Tropical Dry Forest in Costa Rica

Preventing ecosystem damage is cheaper than restoration

About 5% of the earth’s land is preserved from the effects of human activities

Will Restoration Encourage Further Destruction?

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 Protect vital insect pollinators Bluebird protection with special housing boxes Berlin, Germany: rooftop gardens San Francisco: Golden Gate Park

We Can Share Areas We Dominate With Other Species

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

Case Study: The Blackfoot Challenge—Reconciliation Ecology in Action

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

What Can You Do? Sustaining Terrestrial Biodiversity