Environmental Encyclopedia

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Environmental Encyclopedia 3

Alaska National Interest Lands Conservation Act (1980)

Alaska National Interest Lands

Conservation Act (1980)

Commonly known as the Alaska Lands Act, The Alaska

National Interest Lands Conservation Act (ANILCA) law

protected 104 million acres (42 million ha), or 28%, of the

state’s 375 million acres (152 million ha) of land. The law

added 44 million acres (18 million ha) to the

national park

system, 55 million acres (22.3 million ha) to the fish and

wildlife refuge

system, 3 million acres (1.2 million ha) to

the

national forest

system, and made 26 additions to the

national wild and scenic rivers system. The law also desig-

nated 56.7 million acres (23 million ha) of land as

wilder-

ness

, with the stipulation that 70 million acres (28.4 million

ha) of additional land be reviewed for possible wilderness

designation.

The genesis of this act can be traced to 1959, when

Alaska became the forty-ninth state. As part of the statehood

act, Alaska could choose 104 million acres (42.1 million ha)

of federal land to be transferred to the state. This selection

process was halted in 1966 to clarify land claims made by

Alaskan

indigenous peoples

. In 1971, the Alaska Native

Claims Settlement Act (ANSCA) was passed to satisfy the

native land claims and allow the state selection process to

continue. This act stipulated that the Secretary of the Interior

could withdraw 80 million acres (32.4 million ha) of land

for protection as national parks and monuments, fish and

wildlife

refuges, and national forests, and that these lands

would not be available for state or native selection. Congress

would have to approve these designations by 1978. If Con-

gress failed to act, the state and the natives could select any

lands not already protected. These lands were referred to as

national interest or d-2 lands.

Secretary of the Interior Rogers Morton recommended

83 million acres (33.6 million ha) for protection in 1973,

but this did not satisfy environmentalists. The ensuing con-

flict over how much and which lands should be protected,

and how these lands should be protected, was intense. The

environmental community formed the Alaska Coalition,

which by 1980 included over 1,500 national, regional, and

local organizations with a total membership of 10 million

people. Meanwhile, the state of Alaska and development-

oriented interests launched a fierce and well-financed cam-

paign to reduce the area of protected land.

In 1978, the House passed a bill protecting 124 million

acres (50.2 million ha). The Senate passed a bill protecting

far less land, and House-Senate negotiations over a compro-

mise broke down in October. Thus, Congress would not

act before the December 1978 deadline. In response, the

executive branch acted. Department of the Interior Secretary

Cecil Andrus withdrew 110 million acres (44.6 million ha)

from state selection and mineral entry. President Jimmy

Carter then designated 56 million acres (22.7 million ha) of

these lands as national monuments under the authority of

the Antiquities Act. Forty million additional acres (16.2

million ha) were withdrawn as fish and wildlife refuges, and

11 million acres (4.5 million ha) of existing national forests

were withdrawn from state selection and mineral entry. Car-

ter indicated that he would rescind these actions once Con-

gress had acted.

In 1979, the House passed a bill protecting 127 million

acres (51.4 million ha). The Senate passed a bill designating

104 million acres (42.1 million ha) as national interest lands

in 1980. Environmentalists and the House were unwilling

to reduce the amount of land to be protected. In November,

however, Ronald Reagan was elected President, and the

environmentalists and the House decided to accept the Sen-

ate bill rather than face the potential for much less land under

a President who would side with development interests.

President Carter signed ANILCA into law on December

2, 1980.

ANILCA also mandated that the U.S. Geological

Service (USGS) conduct biological and

petroleum

assess-

ments of the coastal plain section of the

Arctic National

Wildlife Refuge

, 19.8 million acres (8 million ha) known

as area 1002. While the USGS did determine a significant

quantity of oil reserves in the area, they also reported that

petroleum development would adversely impact many native

species

, including caribou (Rangifer tarandus), snow geese

(Chen caerulescens), and muskoxen (Ovibos moschatus). In

2001, the Bush administration unveiled a new

energy policy

that would open up this area to oil and

natural gas

explora-

tion. In June 2002, a House version of the energy bill (H.R.4)

that favors opening ANWR to drilling and a Senate version

(S.517) that does not were headed into conference to recon-

cile the differences between the two bills.

[Christopher McGrory Klyza and Paula Anne Ford-Martin]

ESOURCES

OOKS

Lentfer, Hank and C. Servid, eds. Arctic Refuge: A Circle of Testimony.

Minneapolis, MN: Milkweed Editions, 2001.

THER

Alaska National Interest Lands Conservation Act. 16 USC 3101-3223; Public

Law 96-487. [June 2002]. <http://www.access.gpo.gov/uscode/title16/

chapter51_.html>.

Douglas, D. C., et al., eds. Arctic Refuge Coastal Plain Terrestrial Wildlife

Research Summaries. Biological Science Report USGS/BRD/BSR-2002-

0001. [June 2002]. <http://www.absc.usgs.gov/1002>.

RGANIZATIONS

The Alaska Coalition, 419 6th St, #328 , Juneau, AK USA 99801 (907)

586-6667, Fax: (907) 463-3312, Email: info@alaskacoalition.org, <http://

www.alaskacoalition.org>

Environmental Encyclopedia 3

Albedo

Alaska National Wildlife Refuge

see

Arctic National Wildlife Refuge

Alaska pipeline

see

Trans-Alaska pipeline

Albedo

The reflecting power of a surface, expressed as a ratio of

reflected radiation to incident or incoming radiation; it is

sometimes expressed as a percentage. Albedo is also called

the “reflection coefficient” and derives from the Latin root

word albus, which means whiteness. Sometimes expressed

as a percentage, albedo is more commonly measured as a

fraction on a scale from zero to one, with a value of one

denoting a completely reflective, white surface, while a value

of zero would describe an absolutely black surface that re-

flects no light rays.

Albedo varies with surface characteristics such as color

and composition, as well as with the angle of the sun. The

albedo of natural earth surface features such as oceans, for-

ests, deserts, and crop canopies varies widely. Some measured

values of albedo for various surfaces are shown below:

Types of Surface Albedo

Fresh, dry snow cover 0.80–0.95

Aged or decaying snow cover 0.40–0.70

Oceans 0.07–0.23

Dense clouds 0.70–0.80

Thin clouds 0.25–0.50

Tundra 0.15–0.20

Desert 0.25–0.29

Coniferous forest 0.10–0.15

Deciduous forest 0.15–0.20

Field crops 0.20–0.30

Bare dark soils 0.05–0.15

The albedo of clouds in the

atmosphere

is important

to life on Earth because extreme levels of radiation absorbed

by the earth would make the planet uninhabitable; at any

moment in time about 50% of the planet’s surface is covered

by clouds. The mean albedo for the earth, called the planetary

albedo, is about 30–35%.

[Mark W. Seeley]

Algal bloom

Algae are simple, single-celled, filamentous aquatic plants;

they grow in colonies and are commonly found floating in

ponds, lakes, and oceans. Populations of algae fluctuate with

the availability of nutrients, and a sudden increase in nutri-

ents often results in a profusion of algae known as algal

bloom.

The growth of a particular algal

species

can be both

sudden and massive. Algal cells can increase to very high

densities in the water, often thousands of cells per milliliter,

and the water itself can be colored brown, red, or green.

Algal blooms occur in freshwater systems and in marine

environments, and they usually disappear in a few days to

a few weeks. These blooms consume oxygen, increase tur-

bidity, and clog lakes and streams. Some algal species release

water-soluble compounds that may be toxic to fish and shell-

fish, resulting in

fish kills

and

poisoning

episodes.

Algal groups are generally classified on the basis of

the pigments that color their cells. The most common algal

groups are blue-green algae, green algae, red algae, and

brown algae. Algal blooms in freshwater lakes and ponds

tend to be caused by blue-green and green algae. The exces-

sive amounts of nutrients that cause these blooms are often

the result of human activities. For example,

nitrates

and

phosphates

introduced into a lake from

fertilizer runoff

during a storm can cause rapid algal growth. Some common

blue-green algae known to cause blooms as well as release

nerve

toxins

are Microcystis, Nostoc, and Anabaena.

Red tides in coastal areas are a type of algal bloom.

They are common in many parts of the world, including the

New York Bight

, the Gulf of California, and the Red Sea.

The causes of algal blooms are not as well understood in

marine environments as they are in freshwater systems. Al-

though human activities may well have an effect on these

events, weather conditions probably play a more important

role: turbulent storms that follow long, hot, dry spells have

often been associated with algal blooms at sea. Toxic red

tides most often consist of genera from the dinoflagellate

algal group such as Gonyaulax and Gymnodinium. The po-

tency of the toxins has been estimated to be 10 to 50 times

higher than cyanide or curare, and people who eat exposed

shellfish may suffer from paralytic shellfish poisoning within

30 minutes of consumption. A fish kill of 500 million fish

was reported from a

red tide

in Florida in 1947. A number

of blue-green algal genera such as Oscillatoria and Trichodes-

mium have also been associated with red blooms, but they

Environmental Encyclopedia 3

Alligator, American

are not necessarily toxic in their effects. Some believe that

the blooms caused by these genera gave the Red Sea its

name.

The economic and health consequences of algal

blooms can be sudden and severe, but the effects are generally

not long lasting. There is little evidence that algal blooms

have long-term effects on

water quality

ecosystem

structure.

[Usha Vedagiri and Douglas Smith]

ESOURCES

OOKS

Lerman, M. Marine Biology: Environment, Diversity and Ecology. Menlo

Park, CA: Benjamin/Cummings, 1986.

ERIODICALS

Culotta, E. “Red Menace in the World’s Oceans.” Science 257 (11 September

1992): 1476–77.

Mlot, C. “White Water Bounty: Enormous Ocean Blooms of White-

Plated Phytoplankton Are Attracting the Interest of Scientists.” Bioscience

39 (April 1989): 222–24.

Algicide

The presence of nuisance algae can cause unsightly appear-

ance, odors, slime, and coating problems in aquatic media.

Algicides are chemical agents used to control or eradicate

the growth of algae in aquatic media such as industrial tanks,

swimming pools, and lakes. These agents used may vary

from simple inorganic compounds such as

copper

sulphate

which are broad-spectrum in effect and control a variety of

algal groups to complex organic compounds that are targeted

to be species-specific in their effects. Algicides usually re-

quire repeated application or continuous application at low

doses in order to maintain effective control.

Aline, Tundra

see

Tundra

Allelopathy

Derived from the Greek words allelo (other) and pathy (caus-

ing injury to), allelopathy is a form of

competition

among

plants. One plant produces and releases a chemical into the

surrounding

soil

that inhibits the germination or growth

of other

species

in the immediate area. These chemical

substances are both acids and bases and are called secondary

compounds. For example, black walnut (Jugans nigra) trees

release a chemical called juglone that prevents other plants

such as tomatoes from growing in the immediate area around

each tree. In this way, plants such as black walnut reduce

competition for space, nutrients, water, and sunlight.

Allergen

Any substance that can bring about an allergic response in an

organism. Hay fever and

asthma

are two common allergic

responses. The allergens that evoke these responses include

pollen,

fungi

, and dust. Allergens can be described as host-

specific agents in that a particular allergen may affect some

individuals, but not others. A number of air pollutants are

known to be allergens. Formaldehyde, thiocyanates, and ep-

oxy resins are examples. People who are allergic to natural

allergens, such as pollen, are more inclined to be sensitive

also to synthetic allergens, such as formaldehyde.

Alligator, American

The American alligator (Alligator mississippiensis) is a mem-

ber of the reptilian family Crocodylidae, which consists of

species

found in tropical and subtropical regions

throughout the world. It is a species that has been reclaimed

from the brink of

extinction

Historically, the American alligator ranged in the Gulf

and Atlantic coast states from Texas to the Carolinas, with

rather large populations concentrated in the swamps and

river bottomlands of Florida and Louisiana. From the late

nineteenth century into the middle of the twentieth century,

the population of this species decreased dramatically. With

no restrictions on their activities, hunters killed alligators as

pests or to harvest their skin, which was highly valued in

the leather trade. The American alligator was killed in such

great numbers that biologists predicted its probable extinc-

tion. It has been estimated that about 3.5 million of these

reptiles were slaughtered in Louisiana between 1880 and

1930. The population was also impacted by the fad of selling

young alligators as pets, principally in the 1950s.

States began to take action in the early 1960s to save

the alligator from extinction. In 1963 Louisiana banned all

legalized

trapping

, closed the alligator

hunting

season, and

stepped up enforcement of game laws against poachers. By

the time the

Endangered Species Act

was passed in 1973,

the species was already experiencing a rapid recovery. Be-

cause of the successful re-establishment of alligator popula-

tions, its endangered classification was downgraded in several

southeastern states, and there are now strictly regulated sea-

sons that allow alligator trapping. Due to the persistent

demand for its hide for leather goods and an increasing

market for the reptile’s meat, alligator farms are now both

legal and profitable.

Environmental Encyclopedia 3

Alligator, American

An American alligator (

Alligator mississippiensis

). (Photograph by B. Arroyo. U. S. Fish & Wildlife Service. Reproduced by

permission.)

Human fascination with large, dangerous animals,

along with the American alligator’s near extinction, have

made it one of North America’s best studied reptile species.

Population pressures, primarily resulting from being hunted

so ruthlessly for decades, have resulted in a decrease in the

maximum size attained by this species. The growth of a

reptile is indeterminate, and they continue to grow as long

as they are alive, but old adults from a century ago attained

larger sizes than their counterparts do today. The largest

recorded American alligator was an old male killed in January

1890, in Vermilion Parish, Louisiana, which measured 19.2

ft (6 m) long. The largest female ever taken was only about

half that size.

Alligators do not reach sexual maturity until they are

about 6 ft (1.3 m) long and nearly 10 years old. Females

construct a nest mound in which they lay about 35–50 eggs.

The nest is usually 5–7 ft (1.5–2.1 m) in diameter and 2–3

ft (0.6–0.9 m) high, and decaying vegetation produces heat

which keeps the eggs at a fairly constant temperature during

incubation. The young stay with their mother through their

first winter, striking out on their own when they are about

1.5 ft (0.5 m) in length.

[Eugene C. Beckham]

ESOURCES

OOKS

Crocodiles. Proceedings of the 9th Working Meeting of the IUCN/SSC Crocodile

Specialist Group, Lae, Papua New Guinea. Vol. 2. Gland, Switzerland:

IUCN-The World Conservation Union, 1990.

Dundee, H. A., and D. A. Rossman. The Amphibians and Reptiles of Louisi-

ana. Baton Rouge: LSU Press, 1989.

Webb, G. J. W., S. C. Manolis, and P. J. Whitehead, eds. Wildlife Manage-

ment: Crocodiles and Alligators. Chipping Norton, Australia: Surrey Beatty

and Sons, 1987.

THER

“Alligator mississippiensis in the Crocodilians, Natural History and Conser-

vation.” Florida Museum of Natural History. [cited May 2002] <http://

www.flmnh.ufl.edu/cnhc/csp_amis.htm>.

“The American Alligator.” University of Florida, Gainesville. [cited May

2002]. <http://agrigator.ifas.ufl.edu/gators>.

Environmental Encyclopedia 3

Alternative energy sources

Alligator mississippiensis

see

Alligator, American

All-terrain vehicle

see

Off-road vehicles

Alpha particle

A particle emitted by certain kinds of radioactive materials.

An alpha particle is identical to the nucleus of a helium

atom, consisting of two protons and two neutrons. Some

common alpha-particle emitters are uranium-235, uranium-

238, radium-226, and radon-222. Alpha particles have rela-

tively low penetrating power. They can be stopped by a thin

sheet of paper or by human skin. They constitute a health

problem, therefore, only when they are taken into the body.

The inhalation of alpha-emitting

radon

gas escaping from

bedrock into houses in some areas is thought to constitute

a health hazard.

Alternative energy sources

Coal

, oil, and

natural gas

provide over 85% of the total

primary energy used around the world. Although figures

differ in various countries, nuclear reactors and hydroelectric

power together produce less than 10% of the total world

energy. Wind power, active and passive solar systems, and

geothermal energy

are examples of alternative energy

sources. Collectively, these make up the final small fraction

of total energy production.

The exact contribution alternative energy sources make

to the total primary energy used around the world is not

known. Conservative estimates place their share at 3–4%,

but some energy experts dispute these figures.

Amory Lovins

has argued that the

statistics

collected are based primarily

on large

electric utilities

and the regions they serve. They

fail to account for areas remote from major power grids,

which are more likely to use

solar energy

wind energy

,or

other sources. When these areas are taken into consideration,

Lovins claims, alternative energy sources contribute as much

as 11% to the total primary energy used in the United States.

Animal manure, furthermore, is widely used as an energy

source in India, parts of China, and many African nations,

and when this is taken into account the percentage of the

worldwide contribution alternative sources make to energy

production could rise as high as 10–15%. Now an alternative

energy source, wind power is one of the earliest forms of

energy used by humankind. Wind is caused by the uneven

heating of the earth’s surface, and its energy is equal to about

2% of the solar energy that reaches the earth. In quantitative

terms, the amount of kinetic energy within the earth’s

atmo-

sphere

is equal to about 10,000 trillion kilowatt hours.

The kinetic energy of wind is proportional to the wind

velocity, and the ideal location for a windmill generator is

an area with constant and relatively fast winds and no obsta-

cles such as buildings or trees. An efficient windmill can

produce 175 watts per square meter of propeller blade area

at a height of 75 ft (25 m). The estimated cost of generating

one kilowatt hour by wind power is about eight cents, as

compared to five cents for hydropower and 15 cents for

nuclear power

. The largest two utilities in California pur-

chase wind-generated electricity, and though this state leads

the country in the utilization of wind power, Denmark leads

the world. The Scandinavian nation has refused to use nu-

clear power, and it expects to obtain 10% of its energy needs

from windmills.

Solar energy can be utilized either directly as heat or

indirectly by converting it to electrical power using photovol-

taic cells. Greenhouses and solariums are the most common

examples of the direct use of solar energy, with glass windows

concentrating the visible light from the sun but restricting

the heat from escaping. Flatplate collectors are another direct

method, and mounted on rooftops they can provide one

third of the energy required for space heating. Windows

and collectors alone are considered passive systems; an active

solar system uses a fan, pump, or other machinery to trans-

port the heat generated from the sun.

Photovoltaic cells are made of semiconductor materials

such as silicon. These cells are capable of absorbing part of

the solar flux to produce a direct electric current with about

14% efficiency. The current cost of producing photovoltaic

current is about four dollars a watt. However, a thin-film

technology is being perfected for the production of these

cells, and the cost per watt will eventually be reduced because

less materials will be required. Photovoltaics are now being

used economically in lighthouses, boats, rural villages, and

other remote areas. Large solar systems have been most

effective using trackers that follow the sun or mirror reflec-

tors that concentrate its rays.

Geothermal energy is the natural heat generated in

the interior of the earth, and like solar energy it can also be

used directly as heat or indirectly to generate electricity.

Steam is classified as either dry (no water droplets), or wet

(mixed with water). When it is generated in certain areas

containing corrosive sulfur compounds, it is known as “sour

steam,” and when generated in areas that are free of sulfur

it is known as “sweet steam.” Geothermal energy can be

used to generate electricity by the flashed steam method, in

which high temperature geothermal brine is used as a heat

exchanger to convert injected water into steam. The pro-

duced steam is used to turn a turbine. When geothermal

Environmental Encyclopedia 3

Aluminum

wells

are not hot enough to create steam, a fluid which

evaporates at a much lower temperature than water, such as

isobutane or ammonia, can be placed in a closed system

where the geothermal heat provides the energy to evaporate

the fluid and run the turbine.

There are 20 countries worldwide that utilize this en-

ergy source, and they include the United States, Mexico,

Italy, Iceland, Japan, and the former Soviet Union. Unlike

solar energy and wind power, geothermal energy is not free

of environmental impact. It contributes to

air pollution

,it

can emit dissolved salts and, in some cases, toxic

heavy

metals

such as

mercury

and

arsenic

Though there are several ways of utilizing energy from

the ocean, the most promising are the harnessing of

tidal

power

and

ocean thermal energy conversion

. The power

of ocean tides is based on the difference between high and

low water. In order for tidal power to be effective the differ-

ences in height need to be very great, more than 15 ft (3

m), and there are only a few places in the world where such

differences exist. These include the

Bay of Fundy

and a few

sites in China. Ocean thermal energy conversion utilizes

temperature changes rather than tides. Ocean temperature

is stratified, especially near the tropics, and the process takes

advantage of this fact by using a fluid with a low boiling

point, such as ammonia. The vapor from the fluid drives a

turbine, and cold water from lower depths is pumped up to

condense the vapor back into liquid. The electrical power

generated by this method can be shipped to shore or used

to operate a floating plant such as a cannery.

Other sources of alternative energy are currently being

explored, some of which are still experimental. These include

harnessing the energy in

biomass

through the production

of wood from trees or the production of

ethanol

from crops

such as sugar cane or corn.

Methane

gas can be generated

from the

anaerobic

breakdown of

organic waste

in sani-

tary landfills and from

wastewater

treatment plants. With

the cost of

garbage

disposal rapidly increasing, the burning

of garbage is becoming a viable option as an energy source.

Adequate air

pollution

controls are necessary, but trash can

be burned to heat buildings, and municipal garbage is cur-

rently being used to generate electricity in Hamburg, Ger-

many. In an experimental method known as magnetohydrody-

namics, hot gas is ionized (potassium and sulfur) and passed

through a strong magnetic field where it produces an electri-

cal current. This process contains no moving parts and has

an efficiency of 20–30%.

Ethanol and

methanol

can be produced from biomass

and used in

transportation

; in fact, methanol currently

powers Indianapolis race cars.

Hydrogen

could be valuable

if problems of supply and storage can be solved. It is very

clean-burning, forming water, and may be combined with

oxygen in

fuel cells

to generate electricity. Also, it is not

nearly as explosive as

gasoline

Of all the alternative sources,

energy conservation

is perhaps the most important, and improving

energy effi-

ciency

is the best way to meet energy demands without

adding to air and

water pollution

. One reason the United

States survived the energy crises of the 1970s was that they

were able to curtail some of their immense waste. Relatively

easy lifestyle alterations, vehicle improvements, building in-

sulation, and more efficient machinery and appliances have

significantly reduced their potential energy demand. Experts

have estimated that it is possible to double the efficiency of

electric motors, triple the intensity of light bulbs, quadruple

the efficiency of refrigerators and air conditioners, and quin-

tuple the gasoline mileage of automobiles. Several

automo-

bile

manufacturers in Europe and Japan have already pro-

duced prototype vehicles with very high gasoline mileage.

Volvo has developed the LCP 2000, a passenger sedan that

holds four to five people, meets all United States safety

standards, accelerates from 0–50 MPH (0–80.5 km/hr) in

11 seconds, and has a high fuel efficiency rating. Alternative

fuels will be required to meet future energy needs. Enormous

investments in new technology and equipment will be

needed, and potential supplies are uncertain, but there is

clearly hope for an energy-abundant future.

[Muthena Naseri and Douglas Smith]

ESOURCES

OOKS

Alternative Energy Handbook. Englewood Cliffs, NJ: Prentice Hall, 1993.

Brower, M. Cool Energy: Renewable Solutions to Environmental Problems.

Cambridge: MIT Press, 1992.

Brown, Lester R., ed. The World Watch Reader on Global Environmental

Issues. New York: W. W. Norton, 1991.

Goldemberg, J. Energy for a Sustainable World. New York: Wiley, 1988.

Schaeffer, J. Alternative Energy Sourcebook: A Comprehensive Guide to Energy

Sensible Technologies. Ukiah, CA: Real Goods Trading Corp., 1992.

Shea, C. P. Renewable Energy: Today’s Contribution, Tomorrow’s Promise.

Washington, DC: Worldwatch Institute, 1988.

ERIODICALS

Stein, J. “Hydrogen: Clean, Safe, and Inexhaustible.” Amicus Journal 12

(Spring 1990): 33-36.

Alternative fuels

see

Renewable energy

Aluminum

Aluminum, a light metal, comprises about 8% of the earth’s

crust, ranking as the third-most abundant element after oxy-

gen (47%) and silicon (28%). Virtually all environmental

Environmental Encyclopedia 3

Amazon basin

aluminum is present in mineral forms that are almost insolu-

ble in water, and therefore not available for uptake by organ-

isms. Most common among these forms of aluminum are

various aluminosilicate minerals, aluminum clays and sesqui-

oxides, and aluminum

phosphates

However, aluminum can also occur as chemical

spe-

cies

that are available for biological uptake, sometimes caus-

ing toxicity. In general, bio-available aluminum is present

in various water-soluble, ionic or organically complexed

chemical species. Water-soluble concentrations of aluminum

are largest in acidic environments, where toxicity to non-

adapted plants and animals can be caused by exposure to

and Al(OH)

ions, and in alkaline environments, where

Al(OH)

is most prominent. Organically bound, water-

soluble forms of aluminum, such as complexes with fulvic

or humic acids, are much less toxic than ionic species. Alumi-

num is often considered to be the most toxic chemical factor

in acidic soils and aquatic habitats.

Amazon basin

The Amazon basin, the region of South America drained

by the Amazon River, represents the largest area of

tropical

rain forest

in the world. Extending across nine different

countries and covering an area of 2.3 million square mi (6

million sq. km), the Amazon basin contains the greatest

abundance and diversity of life anywhere on the earth. Tre-

mendous numbers of plant and animal

species

that occur

there have yet to be discovered or properly named by scien-

tists, as this area has only begun to be explored by competent

researchers.

It is estimated that the Amazon basin contains over

20% of all higher plant species on Earth, as well as about

20% of all birdlife and 10% of all mammals. More than

2,000 known species of freshwater fishes live in the Amazon

river and represent about 8% of all fishes on the planet, both

freshwater and marine. This number of species is about three

times the entire ichthyofauna of North America and almost

ten times that of Europe. The most astonishing numbers,

however, come from the river basin’s insects. Every expedi-

tion to the Amazon basin yields countless new species of

insects, with some individual trees in the tropical forest

providing scientists with hundreds of undescribed forms.

Insects represent about three-fourths of all animal life on

Earth, yet biologists believe the 750,000 species that have

already been scientifically named account for less than 10%

of all insect life that exists.

However incredible these examples of

biodiversity

are, they may soon be destroyed as the rampant

deforesta-

tion

in the Amazon basin continues. Much of this destruc-

tion is directly attributable to human

population growth

The number of people who have settled in the Amazonian

uplands of Colombia and Ecuador has increased by 600%

over the past 40 years, and this has led to the clearing of

over 65% of the region’s forests for agriculture.

In Brazil, up to 70% of the deforestation is tied to

cattle ranching. In the past large governmental subsidies and

tax incentives have encouraged this practice, which had little

or no financial success and caused widespread environmental

damage. Tropical soils rapidly lose their fertility, and this

allows only limited annual meat production. It is often only

300 lb (136 kg) per acre, compared to over 3,000 lb (1,360

kg) per acre in North America.

Further damage to the tropical forests of the Amazon

basin is linked to commercial

logging

. Although only five

of the approximately 1,500 tree species of the region are

extensively logged, tremendous damage is done to the sur-

rounding forest as these are selectively removed. When log-

gers build roads move in heavy equipment, they may damage

or destroy half of the trees in a given area.

The deforestation taking place in the Amazon basin

has a wide range of environmental effects. The clearing and

burning of vegetation produces

smoke

air pollution

which at times has been so abundant that it is clearly visible

from space. Clearing also leads to increased

soil erosion

after heavy rains, and can result in

water pollution

through

siltation

as well as increased water temperatures from in-

creased exposure. Yet the most alarming, and definitely the

most irreversible, environmental problem facing the Amazon

basin is the loss of biodiversity. Through the irrevocable

process of

extinction

, this may cost humanity more than

the loss of species. It may cost us the loss of potential discov-

eries of medicines and other beneficial products derived from

these species.

[Eugene C. Beckham]

ESOURCES

OOKS

Caufield, C. In the Rainforest: Report From a Strange, Beautiful, Imperiled

World. Chicago: University of Chicago Press, 1986.

Cockburn, A., and S. Hecht. The Fate of the Forest: Developers, Destroyers,

and Defenders of the Amazon. New York: Harper/Perennial, 1990.

Collins, M. The Last Rain Forests: A World Conservation Atlas. London:

Oxford University Press, 1990.

Cowell, A. Decade of Destruction: The Crusade to Save the Amazon Rain

Forest. New York: Doubleday, 1991.

Margolis, M. The Last New World: The Conquest of the Amazon Frontier.

New York: Norton, 1992.

Wilson, E. O. The Diversity of Life. Cambridge, MA: Belknap Press, 1992.

ERIODICALS

Holloway, M. “Sustaining the Amazon.” Scientific American 269 (July 1993):

90–96+.

Environmental Encyclopedia 3

Ambient air

The air, external to buildings and other enclosures, found

in the lower

atmosphere

over a given area, usually near the

surface.

Air pollution

standards normally refer to ambient

air.

Amenity value

The idea that something has worth because of the pleasant

feelings it generates to those who use or view it. This value

is often used in cost-benefit analysis, particularly in

shadow

pricing

, to determine the worth of

natural resources

that

will not be harvested for economic gain. A virgin forest will

have amenity value, but its value will decrease if the forest

is harvested, thus the amenity value is compared to the value

of the harvested timber.

American alligator

see

Alligator, American

American Box Turtle

Box turtles are in the Order Chelonia, Family Emydidae,

and genus Terrapene. There are two major

species

in the

United States: carolina (Eastern box turtle) and ornata

(Western or ornate box turtle).

Box turtles are easily recognized by their dome-shaped

upper shell (carapace) and by their lower shell (plastron)

which is hinged near the front. This hinging allows them

to close up tightly into the “box” when in danger (hence

their name).

Box turtles are fairly small, having an adult maximum

length of 4–7 in (10–18 cm). Their range is restricted to

North America, with the Eastern species located over most

of the eastern United States and the Western species located

in the Central and Southwestern United States and into

Mexico, but not as far west as California. Both species are

highly variable in coloration and pattern, ranging from a

uniform tan to dark brown or black, with yellow spots or

streaks. They prefer a dry

habitat

such as woodlands, open

brush lands, or

prairie

. They typically inhabit sandy

soil

but are sometimes found in springs or ponds during hot

weather. During the winter, they hibernate in the soil below

the frost line, often as deep as 2 ft (60 cm). Their home

range is usually fairly small, and they often live within areas

less than 300 yd

(300 m

Eastern box turtle. (Photograph by Robert Huffman.

Fieldmark Publications. Reproduced by permission.)

Box turtles are omnivorous, feeding on living and dead

insects, earthworms, slugs, fruits, berries (particularly black-

berries and strawberries), leaves, and mushrooms. They have

been known to ingest some mushrooms which are poisonous

to humans, and there have been reports of people eating

box turtles and getting sick. Other than this, box turtles are

harmless to humans and are commonly collected and sold

as pets (although this should be discouraged because they are

now a threatened species). They can be fed raw hamburger,

canned pet food, or leafy vegetables.

Box turtles normally live as long as 30–40 years. Some

have been reported with a longevity of more than one hun-

dred years, and this makes them the longest-lived land turtle.

They are active from March until November and are diurnal,

usually being more active in the early morning. During the

afternoons they typically seek shaded areas. They breed dur-

ing the spring and autumn, and the females build nests from

May until July, typically in sandy soil where they dig a hole

with their hind feet. The females can store sperm for several

years. They typically hatch three to eight eggs that are ellip-

tically-shaped and about 1.5 in (4 cm) in diameter. Male

box turtles have a slight concavity in their plastron that aids

in mounting females during copulation. All four toes on the

male’s hind feet are curved, which aids in holding down the

posterior portion of the female’s plastron during copulation.

Females have flat plastrons, shorter tails, and yellow or brown

eyes. Most males have bright red or pink eyes. The upper

jaw of both sexes ends in a down-turned beak.

Predators of box turtles include skunks, raccoons,

foxes, snakes, and other animals. Native American Indians

used to eat box turtles and incorporated their shells into

their ceremonies as rattles.

[John Korstad]

Environmental Encyclopedia 3

American Committee for International Conservation

ESOURCES

OOKS

Conant, R. A Field Guide to Reptiles and Amphibians of Eastern and Central

North America. Boston: Houghton Mifflin, 1998.

Tyning, T. F. A Guide to Amphibians and Reptiles. Boston: Little, Brown

and Co., 1990.

THER

“Conservation and Preservation of American Box Turtles in the Wild.”

The American Box Turtle Page. Fall 2000 [cited May 2002]. <http://

www.americanboxturtle.freeservers.com>.

American Cetacean Society

The American Cetacean Society (ACS), located in San Pe-

dro, California, is dedicated to the protection of

whales

and other cetaceans, including

dolphins

and porpoises.

Principally an organization of scientists and teachers (though

its membership does include students and laypeople) the

ACS was founded in 1967 and claims to be the oldest whale

conservation

group in the world.

The ACS believes the best protection for whales, dol-

phins, and porpoises is better public awareness about “these

remarkable animals and the problems they face in their in-

creasingly threatened habitat.” The organization is commit-

ted to political action through education, and much of its

work has been in improving communication between marine

scientists and the general public.

The ACS has developed several educational resource

materials on cetaceans, making such products as the “Gray

Whale Teaching Kit,” “Whale Fact Pack,” and “Dolphin

Fact Pack,” which are widely available for use in classrooms.

There is a cetacean research library at the national headquar-

ters in San Pedro, California, and the organization responds

to thousands of inquiries every year. The ACS supports

marine mammal research and sponsors a biennial conference

on whales. It also assists in conducting whale-watching tours.

The organization also engages in more traditional and

direct forms of political action. A representative in Washing-

ton, DC, monitors legislation that might affect cetaceans,

attends hearings at government agencies, and participates as

a member of the International

Whaling

Commission. The

ACS also networks with other conservation groups. In addi-

tion, the ACS directs letter-writing campaigns, sending out

“Action Alerts” to citizens and politicians. The organization

is currently emphasizing the threats to marine life posed by

oil spills

, toxic wastes from industry and agriculture, and

particular fishing practices (including commercial whaling).

The ACS publishes a quarterly newsletter on whale

research, conservation, and education, called WhaleNews,

and a quarterly journal of scientific articles on the same

subjects, called Whalewatcher.

[Douglas Smith]

ESOURCES

RGANIZATIONS

American Cetacean Society, P.O. Box 1391, San Pedro, CA USA

90733-1391 (310) 548-6279, Fax: (310) 548-6950, Email: acs@pobox.com,

<http://www.acsonline.org>

American Committee for International

Conservation

The American Committee for International Conservation

(ACIC), located in Washington, DC, is an association of

nongovernmental organizations (NGOs) that is concerned

about international conservation issues. The ACIC, founded

in 1930, includes 21 member organizations. It represents

conservation groups and individuals in 40 countries. While

ACIC does not fund conservation research, it does promote

national and international conservation research activities.

Specifically, ACIC promotes conservation and preservation

wildlife

and other

natural resources

, and encourages

international research on the

ecology

endangered

species

Formerly called the American Committee for Interna-

tional Wildlife Protection, ACIC assists

IUCN—The World

Conservation Union

, an independent organization of na-

tions, states, and NGOs, in promoting natural resource con-

servation. ACIC also coordinates its members’ overseas re-

search activities.

Member organizations of the ACIC include the Afri-

can Wildlife Leadership Foundation,

National Wildlife

Federation

World Wildlife Fund

(US)/RARE, Caribbean

Conservation Corporation,

National Audubon Society

Natural Resources Defense Council

Nature

Conser-

vancy, International Association of Fish and Wildlife Agen-

cies, and

National Parks and Conservation Association

Members also include The Conservation Foundation, Inter-

national Institute for

Environment

and Development; Mas-

sachusetts Audubon Society; Chicago Zoological Society;

Wildlife Preservation Trust; Wildfowl Trust; School of Nat-

ural Resources, University of Michigan;

World Resources

Institute

; Global Tomorrow Coalition; and The Wildlife

Society, Inc.

ACIC holds no formal meetings or conventions, nor

does it publish magazines, books, or newsletters. Contact:

American Committee for International Conservation, c/o

Environmental Encyclopedia 3

American Farmland Trust

Center for Marine Conservation, 1725 DeSales Street, NW,

Suite 500, Washington, DC 20036.

[Linda Rehkopf]

American Farmland Trust

Headquartered in Washington, DC, the American Farm-

land Trust (AFT) is an advocacy group for farmers and

farmland. It was founded in 1980 to help reverse or at least

slow the rapid decline in the number of productive acres

nationwide, and it is particularly concerned with protecting

land held by private farmers. The principles that motivate

the AFT are perhaps best summarized in a line from William

Jennings Bryan that the organization has often quoted: “De-

stroy our farms, and the grass will grow in the streets of

every city in the country.”

Over one million acres (404,700 ha) of farmland in

the United States is lost each year to development, according

to the AFT, and in Illinois one and a half bushels of

topsoil

are lost for every bushel of corn produced. The AFT argues

that such a decline poses a serious threat to the future of

the American economy. As farmers are forced to cultivate

increasingly marginal land, food will become more expensive,

and the United States could become a net importer of ag-

ricultural products, damaging its international economic po-

sition. The organization believes that a declining farm indus-

try would also affect American culture, depriving the country

of traditional products such as cherries, cranberries, and

oranges and imperiling a sense of national identity that is

still in many ways agricultural.

The AFT works closely with farmers, business people,

legislators, and environmentalists “to encourage sound farm-

ing practices and wise use of land.” The group directs lob-

bying efforts in Washington, working with legislators and

policymakers and frequently testifying at congressional and

public hearings on issues related to farming. In addition to

mediating between farmers and state and federal govern-

ment, the trust is also involved in political organizing at the

grassroots level, conducting public opinion polls, contesting

proposals for incinerators and toxic waste sites, and drafting

model

conservation easements

. They conduct workshops

and seminars across the country to discuss farming methods

and

soil conservation

programs, and they worked with

the State of Illinois to establish the Illinois

Sustainable

Agriculture

Society. The group is currently developing kits

for distribution to schoolchildren in both rural and urban

areas called “Seed for the Future,” which teach the benefits

of agriculture and help each child grow a plant.

The AFT has a reputation for innovative and deter-

mined efforts to realize its goals, and former Secretary of

Agriculture John R. Block has said that “this organization

has probably done more than any other to preserve the

American farm.” Since its founding the trust has been instru-

mental in protecting nearly 30,000 acres (12,140 ha) of

farmland in 19 states. In 1989, the group protected a 507-

acre (205-ha) cherry farm known as the Murray Farm in

Michigan, and it has helped preserve 300 acres (121 ha) of

farm and

wetlands

in Virginia’s Tidewater region. The

AFT continues to battle

urban sprawl

in areas such as

California’s Central Valley and Berks County, Pennsylvania,

as well as working to support farms in states such as Vermont,

which are threatened not so much by development but by

a poor agricultural economy. The AFT promotes a wetland

policy that is fair to farmers while meeting

environment

standards, and it recently won a national award from the

Soil and Water Conservation Society

for its publication

Does Farmland Protection Pay?

The AFT has 20,000 members and an annual budget

of $3,850,000. The trust publishes a quarterly magazine

called American Farmland, a newsletter called Farmland Up-

date, and a variety of brochures and pamphlets which offer

practical information on

soil erosion

, the cost of community

services, and estate planning. They also distribute videos,

including The Future of America’s Farmland, which explains

the sale and purchase of development rights.

[Douglas Smith]

ESOURCES

RGANIZATIONS

The American Farmland Trust (AFT), 1200 18th Street, NW, Suite 800,

Washington, D.C. USA 20036 (202) 331-7300, Fax: (202) 659-8339,

Email: info@farmland.org, <http://www.farmland.org>

American Forests

Located in Washington, DC, American Forests was founded

in 1875, during the early days of the American

conservation

movement, to encourage

forest management

. Originally

called the American Forestry Association, the organization

was renamed in the later part of the twentieth century. The

group is dedicated to promoting the wise and careful use of

all

natural resources

, including

soil

, water, and

wildlife

and it emphasizes the social and cultural importance of these

resources as well as their economic value.

Although benefiting from increasing national and in-

ternational concern about the

environment

, American For-

ests takes a balanced view on preservation, and it has worked

to set a standard for the responsible harvesting and marketing

of forest products. American Forests sponsors the Trees for

People program, which is designed to help meet the national

demand for wood and paper products by increasing the

productivity of private woodlands. It provides educational