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Enger & Smith

Environmental Science A Study of Interrelationships

Twelfth Edition

Chapter 1

Environmental Interrelationships

Environmental Science A Study of Interrelationships

Enger & Smith

Environmental Interrelationships

Outline

The Nature of Environmental Science

Regional Environmental Concerns

Summary

The Nature of Environmental Science

Environmental science is interdisciplinary, and

includes scientific and social aspects of human

impact on the world.

• It is a mixture of traditional science, individual and

societal values, and political awareness.

The Nature of Environmental Science

Environment is

everything that affects

an organism during its

lifetime.

Environmental science

Interrelatedness Is a Core Concept

The study of environmental science is so

interesting, frustrating, and challenging because

of the interrelatedness among seeming

unrelated factors.

Tug on anything at all and you’ll find it

connected to everything else in the universe.

John Muir

Charles Darwin proposed that seed production

in red clover was related to the number of cats in

the area.

Interrelatedness Is a Core Concept

The reintroduction of wolves to Yellowstone

National Park has resulted in many changes.

31 wolves were introduced in 1995.

In 1996 there were about 320 wolves.

The wolves have caused water flow changes in

the park, increases in willow and aspen trees, as

well as songbirds, foxes, certain rodents, hawks,

and owls.

Coyote and elk have declined.

Interrelatedness Is a Core Concept

The Yellowstone wolves are connected to social,

economic, and political realms of human activity.

It was important to environmentalists and

biologists to restore the wolf to its former habitat.

Ranchers could lose money if wolves killed

livestock.

The farm lobby fought long and hard in congress

to prevent the reintroduction.

A fund was developed to pay ranchers for cattle

killed by wolves.

An Ecosystem Approach

An ecosystem is a region in which the organisms

and the physical environment form an interacting

unit.

The task of an environmental scientist is to

recognize and understand the natural interactions

that take place, and to integrate these with the

uses humans must make of the natural world.

Political and Economic Issues

Most social and political decisions are made with

respect to political jurisdictions.

Environmental problems do not necessarily

coincide with artificial political boundaries.

• Air pollution in China affects air quality in the western

coastal U.S. and British Columbia, Canada.

• Air pollution in Mexico affects air quality in Texas.

Political and Economic Issues

International agencies such as the International

Joint Commission have major bearing on

environmental quality over broad regions.

• The International Joint Commission was established in

1909, in part, to protect boundary waters between the

U.S. and Canada.

• The Commission identifies areas of concern and

encourages the cleanup of polluted sites that affect the

quality of the Great Lakes and other boundary waters.

The Global Nature

of Environmental Concerns

The first worldwide meeting of heads of state

directed toward the environment took place at the

Earth Summit (United Nations Conference on

Environment and Development) in Rio de Janeiro

in 1992.

• Most countries at the conference signed agreements on

sustainable development and biodiversity.

The Global Nature

of Environmental Concerns

In 1997, representatives from 125 nations met in

Kyoto, Japan for the Third Conference of the

United Nations Framework Convention on

Climate Change.

• The Kyoto Protocol is viewed as one of the most

important steps to date in environmental protection

and international diplomacy.

The Global Nature

of Environmental Concerns

The Millennium Ecosystem Assessment was

completed in 2005.

• As the human population grows, it puts pressure on

the natural ecosystems of the world.

• Most ecosystems are being negatively affected.

• Food production has increased at the expense of soil

loss due to erosion, conversion of natural ecosystems

to managed systems, and overconsumption of water.

Regional Environmental Concerns

Environmental problems are complex and interrelated with issues specific to a given region.

A regional approach to solving environmental problems is ideal. • Development and logging in the Pacific Northwest

conflict with the survival needs of owls, grizzly bears, and other species.

• In most metropolitan areas, the problem of endangered species is purely historical, as the construction of cities has destroyed previously existing ecosystems.

Regional Environmental Concerns

Regions of North America

The Wilderness North

Much of Alaska and

northern Canada can be

characterized as

“wilderness” — areas

with minimal human

influence.

• Much of this land is owned

by governments, so

governmental policies

have a significant impact.

The Wilderness North

These areas have important economic values in

their trees, animals, scenery, and other natural

resources.

Resource exploitation involves significant trade-

offs. These ecosystems are sensitive to insults and

take a long time to repair damage.

In the past, many short-term political and economic

decisions failed to look at long-term environmental

implications.

Today, politicians are more willing to consider the

scientific and recreational values of wilderness.

The Wilderness North

Native peoples in this area are sensitive to

changes in land use or government policy that

would force changes in traditional ways of life.

They have become increasingly sophisticated in

negotiating with state, provincial, and federal

governments to protect rights they feel they were

granted in treaties.

The Agricultural Middle

The middle of North

America is dominated

by intensive

agriculture.

Original, natural

ecosystems have

been replaced by

managed agriculture.

The Agricultural Middle

Farmland has tremendous economic value.

• It is mostly private land.

• While governments cannot easily control what happens

on private lands, they can

– Encourage activities such as research.

– Grant subsidies to farmers to encourage the planting of certain crops.

– Develop markets for products.

The Agricultural Middle

Managed agricultural land is a major nonpoint

pollution source.

• Tilling causes air pollution in the form of dust.

• Soil erosion causes siltation of rivers and other bodies

of water.

• Nutrients from fertilizers are washed into rivers and

encourage algae growth, lowering water quality.

• Fertilizers and pesticides may enter groundwater and

cause contamination.

The Dry West

The Dry West

This term refers to areas where rainfall is inadequate for agriculture, but adequate for ranching and livestock production.

Because much of the land in the western U.S. is of low economic value, most is still the property of the U.S. government.

The government encourages its use by providing low-cost water for livestock and irrigation, and low-cost grazing rights. It also encourages mining and other development.

The Dry West

Water is an extremely valuable resource in this

region.

• As cities grow, conflict over water rights arises

between urban dwellers and ranchers and farmers.

– Increased demand for water will result in shortages and trade-off

decisions.

The Dry West

Low population density areas have a wilderness

character.

• Conflict has developed between economic land

management for livestock vs. wilderness

preservation.

The Forested West

Coniferous forests

dominate the Pacific

Northwest landscape.

Government and

commercial timber

companies own large

sections of land.

Historically, the

government sold much

of this timber at a loss.

The Forested West

In 1993, the U.S. Forest Service was directed to stop below-cost timber sales. • Timber officials claim access to public land is necessary

for them to remain in business and support the economy.

• Conservationists argue ecological and intangible values outweigh economic values. – Grizzly bear habitat could be significantly altered by logging.

– The northern spotted owl has become a symbol of conflict between logging and preservation.

The Great Lakes and Industrial

Northeast

The Great Lakes and

Northeast are dominated

by large metropolitan

complexes with large,

complicated resource

demands.

Many older cities have

declined, leaving behind

abandoned sites and

environmental problems.

The Great Lakes and Industrial

Northeast

Industrial use of the Great Lakes and East Coast

has resulted in contamination of the water with toxic

materials.

• These pollutants bioaccumulate in the food chain.

– Governments have advised consumers not to eat fish and shellfish from

these areas.

Water generates recreational value.

• Much of the North American population is concentrated

here, so the economic value of water for recreational use

is high.

The Diverse South

The South is a

microcosm of all other

regions.

Extremely rapid

population growth in

some areas has led to

problems with

groundwater,

transportation, and

regulating the rate of

growth.

The Diverse South

Poverty in some areas encourages state and

local governments to accept industrial

development at the expense of other values.

Use of the coastline sometimes encourages

development in unwise areas.

Summary

Environmental science involves science, economics, ethics, and politics in arriving at solutions to environmental problems.

Because ecosystems do not coincide with political boundaries, a regional approach to solving environmental problems is ideal.

Each region of the world has certain environmental issues that are of primary concern because of the mix of population, resource use patterns, and culture.