Ecology
Ecology, also called BIOECOLOGY, BIONOMICS, or ENVIRONMENTAL BIOLOGY, study of the
relationships between organisms and their environment.
Ecological studies may focus on the relationships between individual organisms and the
physical and chemical features of their environment. Ordinarily, the tolerance of an
organism to a range of factors (e.g., salinity or temperature) is measured in the
laboratory. Attempts are then made to relate these results to the distribution of the
organism in natural conditions. An ecologist may study the behaviour of individuals. Among
the characteristics studied would be the food-gathering techniques of individuals, the
survival adaptations against predation, and mating. This area is often referred to as behavioral ecology.
An equivalent study of plants would measure the response of the form of the plant to
environmental change.
Population ecology is the study of the processes that affect the distribution and
abundance of animal and plant populations. The first step is to describe the population.
In order to do this, the birth rate, death rate, and rates of immigration and emigration
are measured. Fluctuations in the numbers of a particular species, proportions of various
species in a population, and predator-prey relationships are all factors that influence
population.
An essential component of population ecology is the study of population genetics
(ecological genetics), which deals with the behaviour of genes in natural populations.
Among areas studied are the change of gene frequencies in nature, the operation of natural
selection on genetic characteristics, and the occurrence of polymorphism in species. These
problems are studied in theoretical model systems, in the laboratory, and in field
populations.
Community ecology is the study of the organization and functioning of communities,
which are assemblages of interacting populations of the species living within a particular
area or habitat. Ecologists study the ranges of species and why some occupy a larger niche
than others, the stability of communities and what factors affect it, the influence of a
particular component (e.g., carnivores) within a community, the nutrient cycle, and
the influence of climate, as well as many other variables. Sophisticated techniques are
available for the description and classification of the different associations of species
that compose a community. These techniques are especially well-developed for plant
communities (phytosociology). Studies show that the structure of communities can change
with time, often in a directional way, known as succession. A community can be viewed as a
complex machine that processes energy and nutrients. To study this machine, it is
necessary to describe the food web and trace the flow of energy and nutrients through it,
from the primary producers (green plants) through the herbivores, carnivores, and
decomposers. One of the principles of community ecology is that the more diverse the
community and the more complex the food web, the greater stability for the community.
A further important area of ecology is paleoecology--the study of the ecology of fossil
organisms. The theory and techniques used in studying present-day organisms are applied to
populations and communities of the past.
Ecologists frequently concentrate on particular taxonomic groups, so that there are
fields of plant ecology or, more narrowly, insect ecology or the ecology of large mammals.
Alternatively, ecologists may study particular environments--e.g., the seashore or
tropical rain forest. In applied ecology, basic ecological principles are applied to the
management of populations of crops and animals, so that yields can be increased and the
impact of pests reduced. Applied ecologists also study the effect of humans on their
environment and on the survival of other species. Theoretical ecologists provide
simulations of particular practical problems (e.g., the effects of fishing on fish
populations) and develop models of general ecological relevance.
Related Internet Links:
KinderGarden
The WWW Virtual Library: Biodiversity, Ecology,
and the Environment
Environmental Education Homepage
Marine Biology Learning
Center: General Ecology
SciCentral: Environment, Ecology, and
Biodiversity
Endangered species
endangered species, any species of plant or animal that is threatened with extinction.
A number of agencies, both international and national, work to maintain lists of
endangered species, to protect and preserve natural habitats, and to promote programs for
recovery and reestablishment of these species. One such international agency is the
Survival Service Commission of the International Union for Conservation of Nature and
Natural Resources (IUCN), which publishes information on endangered species worldwide in a
series of loose-leaf binders called the Red Data Book. Another
agency is the Secretariat for the Convention on International Trade in Endangered Species
of Wild Fauna and Flora.
In the United States the U.S. Fish and Wildlife Service of the Department of the
Interior is responsible for conservation and management of fish and wildlife resources and
their habitats, including endangered species. The service was created in 1940 from the
consolidation of the Bureau of Fisheries (1871) and the Bureau of Biological Survey
(1885). The Endangered Species Act of 1973 (superseding those of 1966
and 1969) obligates the government to protect all animal and plant life threatened with
extinction, including in this category "threatened" species,
defined as any species "which is likely to become endangered in the foreseeable
future throughout all or a significant portion of its range." It also provides for
the drawing up of lists of such species and promotes the protection of critical habitats
(areas designated as critical to the survival of a species).
By 1990 the U.S. Fish and Wildlife Service had compiled a list of almost 1,000 species
of endangered or threatened animals and plants (of which more than 500 are found only in
foreign countries), and some 200 recovery programs were in effect.
Related Internet Links:
Bagheera: A Website for Our Endangered Species
Struggling Upstream:
Restoring Fish to Abrams Creek, Tennessee
Return of the
Species
Hawaii's
Endangered Plants
Endangered Species Home Page, U.S.
Fish and Wildlife Service
California’s
Endangered Insects
Endangered Species -
General Information
Endangered Means There's
Still Time
EE-Link Endangered
Species
Sea World/Busch
Gardens: Endangered Species
The Wild Ones
Whale Adoption
Project
ENVIRONMENT AGENCIES
(EPA), agency of the U.S. government that sets and enforces
national pollution-control standards.
In 1970, in response to the welter of confusing, often ineffective environmental
protection laws enacted by states and communities, President Richard Nixon created the EPA
to fix national guidelines and to monitor and enforce them. Functions of three federal
departments--of the Interior, of Agriculture, and of Health, Education, and Welfare--and
of other federal bodies were transferred to the new agency. The EPA was initially charged
with the administration of the Clean Air Act (1970), enacted to abate
air pollution primarily from industries and motor vehicles; the Federal
Environmental Pesticide Control Act (1972); and the Clean Water Act
(1972), regulating municipal and industrial wastewater discharges and offering grants for
building sewage-treatment facilities. By the mid-1990s the EPA was enforcing 12 major
statutes, including laws designed to control uranium mill tailings; ocean dumping; safe
drinking water; insecticides, fungicides, and rodenticides; and asbestos hazards in
schools.
One of the EPA's early successes was an agreement with automobile manufacturers to
install catalytic converters in cars, thereby reducing emissions of unburned hydrocarbons
by 85 percent. The EPA's enforcement was in large part responsible for a decline of
one-third to one-half in most air-pollution emissions in the United States from 1970 to
1990, and during the 1980s the pollution standards index improved by half in major cities;
significant improvements in water quality and waste disposal also occurred. The Comprehensive Environmental Response, Compensation, and Liability Act
(also called the Superfund), providing billions of dollars for cleaning up abandoned waste
dumps, was first established in 1980, but the number of those waste sites and the
difficulties of the cleanups remained formidable for years thereafter.
Related Internet Links:
Enviro$en$e
Welcome to the United States Environmental Protection
Agency
Envirofacts Warehouse
Ohio Environmental Protection
Agency: Division of Air Pollution Control
ENVIRONMENTALISM
GEOGRAPHY
geography (from Greek geo, "earth," graphein, "to
write"), the scientific study of the Earth's surface. Geography describes and
analyzes the spatial variations in physical, biological, and human phenomena that occur on
the surface of the globe and treats their interrelationships and their significant
regional patterns.
Geography is one of the oldest subjects of study, and it has been called the mother of
sciences. In the classical world geography had close ties with history (as in Herodotus)
in attempting to describe what other lands and peoples were like or with astronomy and
philosophy (as in Eratosthenes and Ptolemy) in trying to ascertain the size of the Earth
and to locate places on it. Alexander von Humboldt
(1769-1859), a German naturalist and geographer, was a key figure in the rise of modern
geography because of his exact measurements, his careful recording of observations, and
his mapping of significant areal patterns of human and natural features.
Though once associated entirely with mapping and the exploration of the Earth, the
discipline of geography is today a wide-ranging one. Any pattern of spatial variation of
phenomena on the surface of the Earth may be influenced by many of the processes that
animate the natural and human realms, requiring geographers to be conversant with the
principles of the biological, social, and earth sciences. Desertification in Africa, for
example, is often attributed to drought, but studies reveal that it has been accelerated
by overgrazing, overexpansion of farming, and removal of trees and shrubs for firewood.
Many such phenomena are studied by other specialists, but it is the distinctive task of
the geographer to investigate their distributional patterns, their regional complexes, the
networks that link the elements, and the processes involved in the interaction among them.
The special subdisciplines of geography are divided into areas of physical, human, and
regional geography. Physical geography is further subdivided into geomorphology,
climatology, biogeography, and hydrology. In this category particular attention has been
paid to coastal areas, to water and mineral resources (including energy), and to natural
hazards. Human geography includes historical geography, cultural and social geography,
population geography, political geography, economic geography (including the study of
agriculture, industry, trade, and transportation), and urban geography. Medical geography,
environmental management, and conservation of resources fall between these two large
fields. The scale of study in regional geography may range from worldwide regionalization,
to a continent, a major cultural area, a country, a subregion within a country, or a city.
Geography utilizes a battery of methods and techniques. Particularly important are
direct field observations and mapping. Methods of observation have been enhanced by such
means as aerial photography and electronic remote sensing from artificial Earth
satellites. Statistical methods help in spatial analysis of quantitative data,
particularly census and survey data. Maps, however, remain the distinctive tool for the
geographer.
The discipline of geography has many uses. It enables individuals to know the basic
features of the world in which they live, the great variety of lands and peoples, the
complex associations and interrelations of human beings with resources and nature, and the
problems faced by inhabitants of other countries and regions. Geographic research provides
explanations of the distribution of physical, biological, and human features on Earth and
of their complex chains of interconnection. Applied geographic analysis has proved useful
in managing resources, in understanding problems of the environment, in analyzing natural
hazards (such as droughts or floods), and in measuring the distribution of environmental
pollution or contamination by discharges of urban, agricultural, and industrial wastes.
The analysis of unanticipated environmental effects caused by the construction of large
dams and reservoirs has been particularly important. Geographers are engaged in planning
land use and housing. They are an important resource in national and international
agencies that deal with the study, inventory, development, or administration of natural or
human resources.
Related Internet Links:
Geography USA: A Virtual
Textbook
Color Landform Atlas of the United States
Oddens's
Bookmarks: The Fascinating World of Maps and Mapping
How Far Is It?
Working with Maps
==============
National Parks
national park, an area set aside by a national government for the preservation of the
natural environment. A national park may be set aside for purposes of public recreation
and enjoyment or because of its historical or scientific interest. Most of the landscapes
and their accompanying plants and animals in a national park are kept in their natural
state. The national parks in the United States and Canada tend to focus
on the protection of both land and wildlife, those in Great Britain focus mainly on the
land, and those in Africa primarily exist to conserve animals. Several other countries
have large areas reserved in national parks, notably Brazil, Japan, India, and Australia.
The concept of a park or nature reserve under state ownership originated in the United
States in 1870, and legislation creating the world's first such park, Yellowstone National
Park in Wyoming, was signed by President Ulysses S. Grant in 1872. Yosemite, Sequoia, and
General Grant national parks were established in 1890, and during this time the idea of
protecting outstanding scenic natural areas for their own sake grew into a concept of
American national policy. The national park system was expanded during the following
decades, and the National Park Service was created in 1916 to administer the parks. By the
late 20th century the American (U.S.) national park system administered more than 350
separate areas comprising about 80 million acres (32 million hectares). In addition to
national parks, the system included national preserves, national monuments, national
recreation areas, national seashores, lakeshores, historic parks and sites, parkways,
scenic trails, and battlefields.
Partly inspired by the American example, movements in favour of national parks sprang
up in many other countries, beginning with Canada, which established its first three
national parks in the mid-1880s. Nature reserves had been maintained in Europe for
centuries to protect hunting grounds for use by kings and nobles, but the establishment of
modern national parks and nature reserves gained momentum only after World War I or, in
some cases, after World War II. Great Britain established the
administrative machinery for both national parks and nature reserves in 1949. It also
began establishing national parks in India and its African colonies after the war, and
this practice was continued and expanded by those new nations after reaching independence.
Japan and Mexico established
their first national parks in the 1930s, but interest in parks generally came later in
Asia and Latin America than it did in the Anglo-American countries and Europe.
The national parks of various countries differ greatly in their effectiveness in
protecting their resources. Some governments provide their park systems with large enough
budgets to make possible strict enforcement of regulations; others do not. Most national
parks have a built-in paradox: although they often depend for their existence on tourism
stimulated by public interest in nature, the preservation of their wildlife depends on its
not being molested. This paradox is usually resolved by allowing visitors to travel only
within limited areas in the park. This lets them see the park while it minimizes their
contact with the wildlife.
Related Internet Links:
Polish National Parks
National Parks Worldwide
Australian World
Heritage Areas
The World Heritage List
Parks in Peril
================
NATIONAL FOREST
national park, an area set aside by a national government for the preservation of the
natural environment. A national park may be set aside for purposes of public recreation
and enjoyment or because of its historical or scientific interest. Most of the landscapes
and their accompanying plants and animals in a national park are kept in their natural
state. The national parks in the United States and Canada tend to focus on the protection
of both land and wildlife, those in Great Britain focus mainly on the land, and those in
Africa primarily exist to conserve animals. Several other countries have large areas
reserved in national parks, notably Brazil, Japan, India, and Australia.
The concept of a park or nature reserve under state ownership originated in the United
States in 1870, and legislation creating the world's first such park, Yellowstone National
Park in Wyoming, was signed by President Ulysses S. Grant in 1872. Yosemite, Sequoia, and
General Grant national parks were established in 1890, and during this time the idea of
protecting outstanding scenic natural areas for their own sake grew into a concept of
American national policy. The national park system was expanded during the following
decades, and the National Park Service was created in 1916 to administer the parks. By the
late 20th century the American (U.S.) national park system administered more than 350
separate areas comprising about 80 million acres (32 million hectares). In addition to
national parks, the system included national preserves, national monuments, national
recreation areas, national seashores, lakeshores, historic parks and sites, parkways,
scenic trails, and battlefields.
Partly inspired by the American example, movements in favour of national parks sprang
up in many other countries, beginning with Canada, which established its first three
national parks in the mid-1880s. Nature reserves had been maintained in Europe for
centuries to protect hunting grounds for use by kings and nobles, but the establishment of
modern national parks and nature reserves gained momentum only after World War I or, in
some cases, after World War II. Great Britain established the
administrative machinery for both national parks and nature reserves in 1949. It also
began establishing national parks in India and its African colonies after the war, and
this practice was continued and expanded by those new nations after reaching independence.
Japan and Mexico established
their first national parks in the 1930s, but interest in parks generally came later in
Asia and Latin America than it did in the Anglo-American countries and Europe.
The national parks of various countries differ greatly in their effectiveness in
protecting their resources. Some governments provide their park systems with large enough
budgets to make possible strict enforcement of regulations; others do not. Most national
parks have a built-in paradox: although they often depend for their existence on tourism
stimulated by public interest in nature, the preservation of their wildlife depends on its
not being molested. This paradox is usually resolved by allowing visitors to travel only
within limited areas in the park. This lets them see the park while it minimizes their
contact with the wildlife.
nature reserve, area set aside by a government for the purpose of preserving certain
animals, plants, or both. A nature reserve differs from a national park in that the latter protects
land and wildlife for public enjoyment, whereas a nature reserve protects animals for
their own sake.
Endangered species are often kept in reserves, away from the hunters who brought them
close to extinction. In the United States, numerous wildlife refuges have served this
purpose, especially with respect to birds. Nature reserves are also numerous in Europe,
India, Indonesia, and some African countries.
The origin of modern nature reserves lies in medieval times, when landowners
established game preserves for the protection of animals that they hunted. The idea of
protecting animals simply to keep them from dying out did not arise until the 19th
century.
Related Internet Links:
Home Page of the Nature Conservancy
-------------------------------------------------------------
Earth tide
, deformation of the solid Earth as it rotates within the gravitational
fields of the Sun and Moon. Earth tides are similar to ocean tides. The Earth deforms
because it has a certain degree of elasticity; were it perfectly rigid, there would be no
Earth tides. Several tidal components mathematically can be shown to exist, but only four
are large enough to be generally measurable; these are the lunar diurnal, the lunar
semidiurnal, the solar diurnal, and the solar semidiurnal tides. Diurnal tides have a period of
approximately 24 hours (1 day), and semidiurnal tides have a period
of approximately 12 hours (1/2 day). The actual amplitudes of these tides in terms of
vertical movement of the surface of the solid Earth are about one foot or less.
Biosphere
biosphere
, relatively thin life-supporting stratum of the Earth's surface,
extending from a few kilometres into the atmosphere to the deep-sea vents of the oceans.
The biosphere is a global ecosystem composed of living organisms (biota) and the abiotic
(nonliving) factors from which they derive energy and nutrients.
A brief treatment of the biosphere follows. For full treatment, see Biosphere .
The biosphere can be broken down into segments of abiotic and biotic components, called
ecosystems.
Oceans, lakes, and wetlands are aquatic ecosystems, while
forests, deserts, and tundras are terrestrial ecosystems. Through
these systems, energy flows and chemicals essential to life are cycled. The biosphere
itself can be studied as a worldwide ecosystem through which the interconnectedness of all
life and life-supporting systems on the Earth can be understood.
Organisms in the biosphere are classified into trophic levels, or feeding
relationships, that constitute the food chain. Primary producers, or autotrophs, are those organisms
that convert energy from the Sun (photoautotrophs) or from inorganic substances
(chemoautotrophs) to produce organic compounds. Green plants make up the largest group of
primary producers. The next trophic level is that of primary consumers, or herbivores (organisms that eat
plants or algae). Secondary consumers are carnivores that feed on herbivores, while
tertiary consumers feed on secondary consumers, and so on. Detritivores, or decomposers,
are consumers that feed on organic detritus.
The process of energy
flow occurs across the trophic levels. Energy enters the system through solar
radiation, which primary producers convert to chemical energy (organic compounds) by the
process of photosynthesis.
Of the light energy that strikes the Earth, only about 1 percent is used in
photosynthesis. Energy flows unidirectionally through the food chain and is dissipated at
each successive stage; roughly 10 percent of energy is transferred from one trophic level
to the next.
Unlike energy, which flows into and out of the system, chemicals are recycled in the
biosphere. Elements essential to life such as carbon, nitrogen, phosphorus, and sulfur are
drawn from the geosphere,
or nonliving world, which consists of the atmosphere (air), the hydrosphere (water), and the lithosphere (rocks
and soil of the terrestrial surface). Once taken up by organisms, the elements cycle
between biotic and abiotic states according to their biogeochemical cycles. The
cycling of water is also necessary to the maintenance of life.
The biotic portion of ecosystems can be broken down into communities--i.e.,
assemblages of populations of different species that live in proximity and may interact
with one another. Populations, still smaller organizational units, are groups of
individuals of the same species located in a particular geographic area. Environmental
conditions such as temperature, water availability, light, and periodic disturbances
affect the distribution of organisms, and interactions between the species themselves
further influence the composition of the community. Interspecific interactions include
competition, antagonism, and predation.
Interactions with the biotic and abiotic components of their ecosystems have shaped the
distribution and evolution of species, resulting in a diverse array of organisms. These
organisms contribute to the steady-state environment of each ecosystem and, thus, to the
maintenance of biospheric processes. Disturbances, both natural and man-made, to even
seemingly small parts of the system may have significant and far-reaching effects.
ecosystem
, the complex of living organisms, their physical environment, and all
their interrelationships in a particular unit of space.
A brief treatment of ecosystems follows. For full treatment, see Biosphere .
The principles underlying the study of ecosystems are based on the view that all the
elements of a life-supporting environment of any size, whether natural or man-made, are
parts of an integral network in which each element interacts directly or indirectly with
all others and affects the function of the whole. All ecosystems are contained within the
largest of them, the ecosphere, which encompasses the entire physical Earth (geosphere)
and all of its biological components (biosphere).
An ecosystem can be categorized into its abiotic constituents, including minerals,
climate, soil, water, sunlight, and all other nonliving elements, and its biotic
constituents, consisting of all its living members. Linking these constituents together
are two major forces: the flow of energy through the ecosystem, and the cycling of
nutrients within the ecosystem.
The fundamental source of energy in almost all ecosystems is radiant energy from the sun. The energy of
sunlight is used by the ecosystem's autotrophic, or self-sustaining,
organisms. Consisting largely of green vegetation, these organisms are capable of photosynthesis--i.e.,
they can use the energy of sunlight to convert carbon dioxide and water into simple,
energy-rich carbohydrates. The autotrophs use the energy stored within the simple
carbohydrates to produce the more complex organic compounds, such as proteins, lipids, and
starches, that maintain the organisms' life processes. The autotrophic segment of the
ecosystem is commonly referred to as the producer level.
Organic matter generated by autotrophs directly or indirectly sustains heterotrophic organisms.
Heterotrophs are the consumers of the ecosystem; they cannot make their own food. They
use, rearrange, and ultimately decompose the complex organic materials built up by the
autotrophs. All animals and fungi are heterotrophs, as are most bacteria and many other
microorganisms.
Together, the autotrophs and heterotrophs form various trophic (feeding) levels in the
ecosystem: the producer level, composed of those organisms that make their own food; the
primary-consumer level, composed of those organisms that feed on producers; the
secondary-consumer level, composed of those organisms that feed on primary consumers; and
so on. The movement of organic matter and energy from the producer level through various
consumer levels makes up a food chain. For example, a
typical food chain in a grassland might be grass (producer) 
mouse
(primary consumer) 
snake
(secondary consumer) hawk
(tertiary consumer). Actually, in many cases the food chains of the ecosystem overlap and
interconnect, forming what ecologists call a food web. The final link in all
food chains is made up of decomposers, those heterotrophs
that break down dead organisms and organic wastes. A food chain in which the primary
consumer feeds on living plants is called a grazing pathway; that in
which the primary consumer feeds on dead plant matter is known as a detritus pathway. Both pathways
are important in accounting for the energy budget of the ecosystem.
As energy
moves through the ecosystem, much of it is lost at each trophic level. For example, only
about 10 percent of the energy stored in grass is incorporated into the body of a mouse
that eats the grass. The remaining 90 percent is stored in compounds that cannot be broken
down by the mouse or is lost as heat during the mouse's metabolic processes. Energy losses
of similar magnitude occur at every level of the food chain; consequently, few food chains
extend beyond five members (from producer through decomposer), because the energy
available at higher trophic levels is too small to support further consumers.
The flow of energy through the ecosystem drives the movement of nutrients within the ecosystem.
Nutrients are chemical elements and compounds necessary to living organisms. Unlike
energy, which is continuously lost from the ecosystem, nutrients are cycled through the
ecosystem, oscillating between the biotic and abiotic components in what are called biogeochemical cycles.
Major biogeochemical cycles include the water cycle, carbon cycle, oxygen cycle, nitrogen
cycle, phosphorus cycle, sulfur cycle, and calcium cycle. Decomposers play a key role in
many of these cycles, returning nutrients to the soil, water, or air, where they can again
be used by the biotic constituents of the ecosystem.
The orderly replacement of one ecosystem by another is a process known as ecosystem
development, or ecological
succession. Succession occurs when a sterile area, such as barren rock or a lava flow,
is first colonized by living things or when an existing ecosystem is disrupted, as when a
forest is destroyed by a fire. The succession of ecosystems generally occurs in two
phases. The early, or growth, phase is characterized by ecosystems that have few species
and short food chains. These ecosystems are relatively unstable but highly productive, in
the sense that they build up organic matter faster than they break it down. The ecosystems
of the later, or mature, phase are more complex, more diversified, and more stable. The
final, or climax, ecosystem is characterized by a great diversity of species, complex food
webs, and high stability. The major energy flow has shifted from production to
maintenance.
Human interference in the development of ecosystems is widespread. Farming, for
example, is the deliberate maintenance of an immature ecosystem--one that is highly
productive but relatively unstable. Sound management of ecosystems for optimal food
production should seek a compromise between the characteristics of young and mature
ecosystems, and should consider factors that affect the interaction of natural cycles.
Short-term production can be maximized by adding energy to the ecosystem in the form of
cultivation and fertilization. Such efforts, however, can hinder efficient energy use in
the long run by producing an imbalance of nutrients, an increase in pollutants, or a
heightened susceptibility to plant diseases as a consequence of intensive inbreeding of
crops. (see also Index: agriculture)
Although an awareness of the interdependence between human society and its environment
was already prominent in ancient philosophy and religion, the formulation of the basic
principles of systems ecology as a scientific discipline began in the late 19th century.
During the second half of the 20th century, the study of ecosystems has become
increasingly sophisticated and is now instrumental in the assessment and control of the
effects of agricultural development and industrialization on the environment. On farms,
for instance, it has shown that optimal long-term production of pasturage requires a
moderate grazing schedule in order to ensure a steady renewal of the moisture and nutrient
content of the soil and has emphasized the need for multiple-use strategies in the
cultivation of arable lands. Systems ecology has been concerned with the consequences of
accumulated insecticides and has provided a way of monitoring the climatic effects of
atmospheric dust and carbon dioxide released by the burning of fossil fuels (e.g.,
coal, oil, and natural gas). It has helped to determine regional population capacities and
has furthered the development of recycling techniques that may become essential in
humanity's future interaction with the environment.
Introduction
Although the idea of conservation is probably as old
as the human species, the use of the word in its present context is relatively recent.
Over the years conservation has acquired many connotations: to some it has meant the
protection of wild nature, to others the sustained production of useful materials from the
resources of the Earth. The most widely accepted definition, presented in 1980 in World
Conservation Strategy by the International Union for Conservation of Nature and
Natural Resources, is that of "the management of human use of the biosphere so that
it may yield the greatest sustainable benefit while maintaining its potential to meet the
needs and aspirations of future generations." The document defines the objectives of
the conservation of living resources as: maintenance of essential ecological processes and
life-support systems, preservation of genetic diversity, and guarantee of the sustainable
use of species and ecosystems. More generally, conservation involves practices that
perpetuate the resources of the Earth on which human beings depend and that maintain the
diversity of living organisms that share the planet. This includes such activities as the
protection and restoration of endangered species, the careful use or recycling of scarce
mineral resources, the rational use of energy resources, and the sustainable use of soils
and living resources.
Conservation is necessarily based on a knowledge of ecology, the science concerned with
the relationship between life and the environment, but ecology itself is based on a wide
variety of disciplines, and conservation involves human feelings, beliefs, and attitudes
as well as science and technology.
environmentalism
, in the social sciences, any theory that emphasizes the importance
of environmental factors in the development of culture and society.
The theory of environmental determinism states that the physical
milieu of a people, including natural resources, climate, and geography, is the major
determining factor in the formation of their culture. Determinism thereby rejects history
and tradition, social and economic factors, and other aspects of culture as explanations
of social development. Environmental possibilism, an opposing
doctrine, suggests that habitat acts only to create possibilities from which people may
choose.
Contemporary environmentalists recognize that physical surroundings are only part of a
total environment that includes social and economic factors, cultural tradition, and
reciprocal influences between societies and their environment.
Related Internet Links:
Center for the Study of Values in Public
Life
EarthSharing Homepage
Pollution
as Delusion
The Adventures of Alex Online
BWZine: The Online Better World
Magazine
Ecomall
Ecology Hall of Fame
Environmental News Network
EnviroLink
Envirofacts Warehouse
Green Shopping for Sustainable Living
Eco Net
The Green Lane
Environmental Journalism Home Page
environmentalism
, in the social sciences, any theory that emphasizes the importance
of environmental factors in the development of culture and society.
The theory of environmental determinism states that the physical
milieu of a people, including natural resources, climate, and geography, is the major
determining factor in the formation of their culture. Determinism thereby rejects history
and tradition, social and economic factors, and other aspects of culture as explanations
of social development. Environmental possibilism, an opposing
doctrine, suggests that habitat acts only to create possibilities from which people may
choose.
Contemporary environmentalists recognize that physical surroundings are only part of a
total environment that includes social and economic factors, cultural tradition, and
reciprocal influences between societies and their environment.
Related Internet Links:
Center for the Study of Values in Public
Life
EarthSharing Homepage
Pollution
as Delusion
The Adventures of Alex Online
BWZine: The Online Better World
Magazine
Ecomall
Ecology Hall of Fame
Environmental News Network
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Greenpeace, international organization dedicated to preserving endangered species of
animals, preventing environmental abuses, and heightening environmental awareness through
direct confrontations with polluting corporations and governmental authorities. Greenpeace
was founded in 1971 in British Columbia to oppose U.S. nuclear testing at Amchitka Island
in Alaska. The loose-knit organization quickly attracted support from ecologically minded
individuals and began undertaking campaigns seeking, among other goals, the protection of
endangered whales and seals from hunting, the cessation of the dumping of toxic chemical
and radioactive wastes at sea, and the end of nuclear-weapons testing. The primary tactic
of Greenpeace has been such "direct, nonviolent actions" as steering small
inflatable craft between the harpoon guns of whalers and their cetacean prey and the
plugging of industrial pipes discharging toxic wastes into the oceans and the atmosphere.
Such dangerous and dramatic actions brought Greenpeace wide media exposure and helped
mobilize public opinion against environmentally destructive practices. Greenpeace also
actively sought favourable rulings from national and international regulatory bodies on
the control of environmental abuses, sometimes with considerable success. The organization
has a small staff and relies largely on voluntary staffing and funding. (see also Index:
pollution)
On July 10, 1985, the Greenpeace ship Rainbow Warrior, which
was due to sail to Moruroa Atoll to protest French atmospheric nuclear-weapons tests
there, was sunk by two bomb explosions while berthed in Auckland Harbour, N.Z. Subsequent
revelations that French intelligence agents had planted the bombs caused a major
international scandal and led to the resignation of France's minister of defense and the
dismissal of the head of its intelligence service.
Related Internet Links:
Greenpeace Australia
Greenpeace International
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United nations conference environment
United Nations Conference on Environment and Development (UNCED), byname EARTH SUMMIT,
conference held at Rio de Janeiro, Brazil (June 3-14, 1992), to reconcile worldwide
economic development with protection of the environment. The Earth Summit was the largest
gathering of world leaders in history, with 117 heads of state and representatives of 178
nations in all attending. By means of treaties and other documents signed at the
conference, most of the world's nations nominally committed themselves to the pursuit of
economic development in ways that would protect the Earth's environment and nonrenewable
resources.
The main documents agreed upon at the Earth Summit are as follows. The Convention on Biological Diversity is a binding treaty requiring nations to take
inventories of their plants and wild animals and protect their endangered species. The
Framework Convention on Climate Change, or Global Warming Convention,
is a binding treaty that requires nations to reduce their emission of carbon dioxide,
methane, and other "greenhouse" gases thought to be responsible for global
warming; the treaty stopped short of setting binding targets for emission reductions,
however. The Declaration on Environment and Development, or Rio
Declaration, laid down 27 broad, nonbinding principles for environmentally sound
development. Agenda 21 outlined global strategies for cleaning up the
environment and encouraging environmentally sound development. The Statement of Principles
on Forests, aimed at preserving the world's rapidly vanishing tropical
rainforests, is a nonbinding statement recommending that nations monitor and assess the
impact of development on their forest resources and take steps to limit the damage done to
them.
The Earth Summit was hampered by disputes between the wealthy industrialized nations of
the North (i.e., western Europe and North America) and the poorer developing countries of the
South (i.e., Africa, Latin America, the Middle East, and parts of Asia). In
general, the countries of the South were reluctant to hamper their economic growth with
the environmental restrictions urged upon them by the North unless they received increased
Northern financial aid, which they claimed would help make environmentally sound growth
possible.
United Nations programme
United Nations Environment Programme
(UNEP), UN organization established in 1972 to
guide and coordinate environmental activities within the United Nations system. UNEP
recommends to its parent body policies that will promote environmental cooperation on an
international level. Earthwatch, an international monitoring system devised to facilitate
information exchanges among governments, is UNEP's most widely recognized activity.
Participation in this enterprise enables members to assess significant environmental risks
and to act accordingly.
The Governing Council is composed of 58 members who are elected by the UN General
Assembly.
Related Internet Links:
United Nations Environment Programme
nature reserve
, area set aside by a government for the purpose of preserving
certain animals, plants, or both. A nature reserve differs from a national
park (q.v.) in that the latter protects land and wildlife for public
enjoyment, whereas a nature reserve protects animals for their own sake.
Endangered species
are often kept in reserves, away from the hunters who brought them close to extinction. In
the United States, numerous wildlife refuges have served this purpose, especially with
respect to birds. Nature reserves are also numerous in Europe, India, Indonesia, and some
African countries.
The origin of modern nature reserves lies in medieval times, when landowners
established game preserves for the protection of animals that they hunted. The idea of
protecting animals simply to keep them from dying out did not arise until the 19th
century.
Related Internet Links:
Home Page of the Nature Conservancy
