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Glossary

ABIOTIC

Usually refers to the physical and chemical components of an organism's environment.

ABSOLUTE HUMIDITY

Measurement of atmospheric humidity. Absolute humidity is the mass of water vapour in a given volume of air (this measurement is not influenced by the mass of the air). Normally expressed in grams of water vapour per cubic meter of atmosphere at a specific temperature.

ABSORBTION CAPACITY

Capacity for a porous body of a substance of absorbing liquids and gas in all its mass.

ABSORPTION

The taking up of substances or their passage through the walls of cells.

ABYSSAL ZONE

Pertaining to zones of great depth in the oceans or lakes into which light does not penetrate; occasionally restricted to depths below 2,000 meters but more usually used for depths between 4,000 and 6,000 meters.

ACARI

Arthropods Arachnids generally with small or smallest dimensions; commonly called "mites", they are more known as parasites of the plants and the animals, but the greater part of these Arachnids colonizes the most various environments enclosed the caves where some species show a remarkable degree of specialization.

ACETONE

An organic solvent of industrial and chemical significance, acetone is capable of dissolving many fats, resins and cellulose esters. It is used extensively in the manufacture of artificial fibres and explosives, as a chemical intermediate in pharmaceuticals, and as a solvent for vinyl and acrylic resins, lacquers, paints, inks, cosmetics (such as nail polish remover), and varnishes. It is used in the preparation of paper coatings, adhesives, and is also employed as a starting material in the synthesis of many compounds.

ACID

A class of compounds that can be corrosive when concentrated. Weak acids, such as vinegar and citric acid, are common in foods. Strong acids, such as muriatic (or hydrochloric), sulfuric and nitric acid have many industrial uses, and can be dangerous to those not familiar to handling them. Acids are chemical "opposites" to bases, in that they can neutralize each other.

ACID DEPOSITION (ACID POLLUTION)

Atmospheric precipitation with a pH less than 5.6. Normal pH of precipitation is 5.6.

ACIDIFICATION

Acid Rain: rain , snow or fog that is polluted by acid in the atmosphere and damages the environment. Two common air pollutants acidify rain: sulphur dioxide (SO2) and nitrogen oxide (NOx). When the environment (as lakes, rivers and soils) cannot neutralize the acid being deposited, damage occurs.

ACIDOGENIC

Producing acid, as bacteria, or causing acidity, as of the urine.

ACOUSTIC TREATMENT

Physical object - such as a pillow, panel, or any other freestanding or wall-hanging device - that's used to improve the acoustic properties of a listening room. Typically works by absorbing reflections of sound waves, though some acoustic treatments may instead diffuse reflections.

ACTIVATED CARBON

Activated charcoal or activated carbon is an amorphous form of carbon. This means that it has no regular atomic structure, unlike the other forms (allotropes) of elemental carbon: diamond, graphite, fullerenes or nanotubes.

ACTIVATED SLUDGE

Sludge made up of clumps of living organisms feeding on detritus that settles out and is recycled in the process of secondary wastewater treatment.

ADAPTATION

A confusing word used to mean quite different things. (I) Characteristics of organisms evolved as a consequence of natural selection in its evolutionary past and which result in a close match with features of the environment and/or constrain the organism to life in a narrow range of environments. The prefix 'ad-' is unfortunate as it implies that the process anticipates the present or the future (II) Changes in the form or behaviour of an organism during its life as a response to environmental stimuli, e.g. the formation of sun and shade leaves on the same tree and the acquisition of cold tolerance as a result of prior experience of low temperatures. (III) Changes in the excitability of a sense organ as a result of continuous stimulation.

ADDITIVE

A constituent component that may be added to the composite matrix to modify its properties and in general, enhance its performance. Additives include catalysts, colorants, flame retardants and other ingredients that expand and improve the capabilities of the matrix.

ADSORPTION

The taking up of the molecules from a gas or liquid on the surface of another substance; distinguished from absorption, a process where one substance actually penetrates into the inner structure of the other.

AERATION

An organism that requires free oxygen for growth.

AEROBE

Aerobic means living in air. Aerobic can also describe a type of cellular respiration in which foodstuffs (usually carbohydrates) are completely oxidized into carbon dioxide and water with the production of chemical energy, in a process requiring atmospheric oxygen.

AEROBIC

Aerobic means living in air. Aerobic can also describe a type of cellular respiration in which foodstuffs (usually carbohydrates) are completely oxidized into carbon dioxide and water with the production of chemical energy, in a process requiring atmospheric oxygen.

AEROMAGNETIC DATA/SURVEYS

Measured variations in the Earth's magnetic field, collected from an airplane, typically flown at low altidude (300 m or less). Aeromagnetic surveys usually consists of a large number of parallel flight lines to provide continues data coverage.

AEROSOL

A suspension of small liquid or solid particles in gas.

AEROSTAT

Generic term for the two forms of lighter-than-air crafts, the hot-air balloon and the airship (blimp).

AFFORESTATION

The establishment of forest by natural succession or by the planting of trees on land where they did not grow formerly.

AGENDA 21

"the plan of action to achieve sustainable development that was adopted by world leaders at the United Nations Conference on Environment and Development held in Rio de Janeiro, Brazil, in June 1992 (United Nations, 1993b)." Source: United Nations, Glossary of Environment Statistics

AGROECOSYSTEM

A crop field is an ecosystem in which ecological processes found in other vegetation formations such as nutrient cycling, predator/prey interactions, competition, commensalism and successional changes occur.

AIR EMISSIONS

The release or discharge of a pollutant (from a stationary source) into the ambient air. For anthropogenic sources this may involve release (1) by means of a stack or (2) as a fugitive dust, mist or vapor as a result inherent to the manufacturing or formulating process. Pollutants may also be discharged from mobile sources, from area sources such as roads and fields, and from non-manufacturing, stationary sources.

AIR MONITORING

The continuous sampling for, and measuring of, pollutants present in the atmosphere.

AIR POLLUTANT

Dust, fumes, mist, smoke and other particulate matter, vapor, gas, odorous substances, or any combination thereof; any air pollution agent or combination of such agents, including any physical, chemical, biological, radioactive (including source material, special nuclear material, and by-product material) substance or matter which is emitted into or otherwise enters the ambient air. "Substance in air that could, in high enough concentration, harm man, other animals, vegetation, or material. They may be in the form of solid particles, liquid droplets, gases, or in combination thereof. Generally, they fall into two main groups “ Source: United States Environmental Protection Agency, Terms of Environment

AIR POLLUTION

The presence of any substances in air that do not disperse and that can, in high enough concentrations, harm humans or other animals, vegetation, or materials. Pollutants can include almost any natural or artificial substance capable of being airborne as solid particles, liquid droplets, and gases, or a combination of these forms. Generally, air pollutants fall into two major groups: (1) those emitted directly from identifiable sources and (2) those produced in the air when two or more primary pollutants interact, or that react with normal atmospheric constituents. Excluding pollen, fog, and dust, which are of natural origin, about 100 pollutants have been identified and fall into the following major categories: solids, sulfur compounds, volatile organic chemicals, nitrogen compounds, oxygen compounds, halogen compounds, radioactive compounds, and odors. Air pollution is most serious in urban areas. Regional and state laws have set limits on certain air pollutants.

AIR POLLUTION CONTROL DEVICE

Mechanism or equipment that cleans emissions generated by an incinerator by removing pollutants that would otherwise be released to the atmosphere.

AIR QUALITY CRITERIA

The levels of pollution and lengths of exposure above which adverse effects may occur on health and welfare.

AIR QUALITY MONITORING/ ALSO SEE MONITORING

Continuous or frequent standardized measurement and observation of the environment (air, water, land/soil, biota), often used for warning and control. Scientists collect and anlyze samples of air in different regions of their own country on a regular basis to determine pollutant levels. This information is not only used by decision-makers to pinpoint the sources of air pollution and determine strategies for reducing it, but also to produce daily air-quality forecasts that warn citizens when smog levels are high.

AIR QUALITY STANDARDS

The level of pollutants prescribed by law or regulation that cannot be exceeded during a specified time in a defined area.

AIR SPARGING

In air sparging, air is injected into the ground below a contaminated area, forming bubbles that rise and carry trapped and dissolved contaminants to the surface where they are captured by a soil vapor extraction system. Air sparging may be a good choice of treatment technology at sites contaminated with solvents and other volatile organic compounds (VOCs).

ALBEDO

1-A measure of surface reflectivity, usually expressed as a percentage, such as the proportion of solar radiation that is reflected back into space from the Earth, clouds, and atmosphere without heating the receiving surface. Studying a planet's albedo can help determine the composition of its surface.Albedo. A measure of surface reflectivity, usually expressed as a percentage, such as the proportion of solar radiation that is reflected back into space from the Earth, clouds, and atmosphere without heating the receiving surface. Studying a planet's albedo can help determine the composition of its surface. 2-Reflectivity. When radiation strikes a body, albedo is a measure of the fraction reflected, either back towards the source or anywhere away from the body. In climate considerations, albedo refers to the percentage of solar radiation reflected back from the Earth into space (about 30% on average). The albedo of any locale depends upon many factors, including the color and roughness of the terrain, the extent of forest or agriculture cover, and the amount of cloud and snow cover. Clouds, ice and snow reflect a greater proportion of radiation than do land and ocean surfaces (Source: Mintzer, 1992).

ALCOHOLS AND GLYCOLS

Alcohols - A series of hydrocarbon derivatives with at least one hydrogen atom replaced by an -OH group. The simplest alcohols (methanol, ethanol, n-propanol, and isopropanol) are good solvents for some organic soils, notably rosin, but are flammable and can form explosive mixtures with air. The use of flammable solvents requires caution and well-designed equipment. Glycols- A loose term for a diol or a dihydric alcohol, i.e. one containing two -OH groups per molecule. Glycols and related compounds, esp. diglycol ethers, are often used as components in proprietary solvents and cleaning additives.

ALGAL BLOOM

In aquatic ecosystems, the rapid growth or proliferation of algae, usually visible to the naked eye, commonly referred to as Algal Bloom or Algae Bloom; often related to pollution, especially when pollutants accelerate growth.

ALKYLATING AGENT

A chemical agent that can add alkyl groups (for example, ethyl or methyl groups) to another molecule; many mutagens act through alkylation.

ALKYLATION

The addition of an alkyl group to an organic molecule. Generally limited to the reaction of an olefine molecule with an iso-paraffin resulting in the formation of an iso-paraffin of higher molecular weight.

ALLOY

A metal that is manufactured by combining two or more molten metals. An alloy is always harder than its component metals. Bronze is an alloy of copper and tin.

ALTERNATIVE ENERGY SOURCES

Energy sources different from those in widespread use at the moment (which are referred to as conventional). Alternative energy usually includes solar, wind, wave, tidal, hydroelectric and geothermal energy. Although they each have their own drawbacks, none of these energy sources produces significant air pollution, unlike conventional sources.

ALTERNATOR

A device that converts rotational energy to AC current. Alternators provide energy for the vehicle electrical system. The alternator also recharges the battery.

ALTITUDE

In geography, vertical height (in m or feet) of a point above the marine medium level.

AMMINOACID

Organic nitrogen containing acids which are used to construct proteins. Any of a class of 20 molecules that are combined to form proteins in living things. The sequence of amino acids in a protein and hence protein function are determined by the genetic code.

AMMONIA

Chemical compound composed of nitrogen and hydrogen (NH3). Component of the nitrogen cycle. Immediately released from organic matter upon decomposition.

AMORPHOUS SUBSTANCE

A substance whose particles have no regular pattern.

ANAEROBE

An organism that grows in the absence of oxygen.

ANAEROBIC

Referring to an environment in which oxygen is absent, or to a process which occurs only in the absence of oxygen, or to an organism which lives, is active, or occurs in the absence of oxygen, such as some yeasts or bacteria.Anaerobic.

ANAEROBIC DIGESTION

Decomposition of biological wastes by micro-organisms, usually under wet conditions, in the absence of air (oxygen), to produce a gas comprising mostly methane and carbon dioxide.

ANGIOSPERM

Angiosperms (meaning "covered seed") are flowering plants. They produce seeds enclosed in fruit (an ovary). They are the dominant type of plant today; there are over 250,000 species. Their flowers are used in reproduction. Angiosperms evolved about 145 million years ago, during the late Jurassic period, and were eaten by dinosaurs. They became the dominant land plants about 100 million years ago (edging out conifers, a type of gymnosperm). Angiosperms are divided into the monocots (like corn) and dicots (like beans).

ANILINE (C6H7N)

Also phenylamine, (C6H5NH2), colorless liquid, slightly soluble in water and soluble in organic solvents. It was first prepared in 1826 as one of the products obtained by heating indigo to a high temperature. The word aniline is derived from the specific name, anil, of the indigo plant, which in turn is derived from the Sanskrit word nila ("blue" or "indigo").

ANIMAL

Organisms that belong to the kingdom Animalia. General characteristics of these organisms include: eukaryotic cell type, mitochondria, and a complex nervous system. This group of life includes organism like sponges, jellyfishes, arthropods (insects, shrimp, and lobsters), mollusks (snails, clams, oysters, and octopuses), fish, amphibians (frogs, toads, and salamanders), reptiles (turtles, lizards, alligators, crocodiles, snakes), birds, and mammals (kangaroos, bats, cats, rabbits, elephants, whales, porpoises, monkeys, apes, and humans).

ANNELIDS

Any of a phylum (Annelida) of usually elongated, segmented coelomate invertebrates, such as earthworms, various marine worms, and leeches.

ANTHRACITE

Hard coal, found deep in the earth. It burns very hot, with little flame. It usually has a heating value of 12,000 – 15,000 British Thermal Units (Btus) per pound.

ANTHROPIC

Of or relating to humans or the era of human life.

ANTHROPIZATION

The effect of human action on natural environments.

ANTHROPOGENIC

Refers to something originating from humans and the impact of human activities on nature.

ANTICLINE

A fold in rock layers that forms an arch.

ANTICRITTOGAMICI

(see Fungicides)

ANTIOXIDANT

A group of additives which provide thermal protection, mostly by intervening within the oxidation process. A substance added to latex and synthetic gloves to prevent or delay deterioration of the glove by the oxygen in air.

APHOTIC ZONE

Bottom most layer of the ocean zones, where light does not reach.

API (AMERICAN PETROLEUM INSTITUTE)

American Petroleum Institute. The primary US oil industry trade association, based in Washington, DC. API conducts research and sets technical standards for industry equipment and products from wellhead to retail outlet. It also compiles statistics which are regarded as industry benchmarks.

API GRAVITY

The universally accepted scale adopted by the American Petroleum Institute (API) for expressing the density of liquid petroleum products. The higher the API gravity, the lighter the oil.

API SEPARATOR

A facility developed by the Committee on Disposal or Refinery Wastes of the American Petroleum Institute (see) for separation of oil from wastewater in a gravity differential and equipped with means for recovering the separated oil and removing sludge.

AQUIFER

A water-bearing layer of rock or sediment that is capable of yielding useable amounts of water. Drinking water and irrigation wells draw water from the underlying aquifer.

ARACHNIDES

Arachnida (Class): Belonging to the phylum Arthropoda like the Classes Crustacea, Chilopoda (millipedes), Diplopoda (centipedes) and the immense Class of Insecta. The Arachnids are an Arthropods group very well definite, also if it groups different forms: the Scorpiones are well-known from the antiquity, the Pseudoscorpiones are less known because of its little dimensions and its particular habitat, the Opiliones carry characteristic lengthened legs and a subspherical body, the Araneae (true spiders) are definitely the more known Order, diffuse in every environment, and the Acari (mites) are known as parasites of plants and animals. Together the Diplopoda, the Aracnida have been the first Arthropods that colonized the terrestrial environment from the Silurian, over 450 million years ago.

ARID REGION

Region in which precipitation is too low to support crop production.

AROMATICS

Aromatics are organic compounds that contain 6-carbon ring structures, suchs as creosote, toluene, and phenol, that often are found at dry cleaning and electronic assembly sites.

ASBESTOS

A general name given a family of naturally occurring fibrous silicate minerals. Asbestos fibers were used mainly for insulation and as a fire retardant material in ship and building construction and other industries, and in brake shoes and pads for automobiles. Inhaling asbestos fibers has been shown to result in lung disease (asbestosis) and in lung cancer (mesothelioma). The risk of developing mesothelioma is significantly enhanced in smokers.

ASH CONTENT

Impurities consisting of silica, iron, alumina, and other noncombustible matter that are contained in coal. Ash increases the weight of coal, adds to the cost of handling, and can affect its burning characteristics. Ash content is measured as a percent by weight of coal on an "as received" or a "dry" (moisture-free, usually part of a laboratory analysis) basis.

ASPHALT

A dark-brown to black cement-like material obtained by petroleum processing, containing bitumens as the predominant constituents. Includes crude asphalt as well as the following finished products: cements, the asphalt content of emulsions (exclusive of water), and petroleum distillates blended with asphalt to make cutback asphalts.

ASPHALTENES

Insoluble, semi-solid, or solid particles which are combustible and are highly aromatic. Asphaltenes contain a high carbon to hydrogen ratio and entrap water, fuel ashes and other impurities.

ASTEROID

One of billions of rocky objects, less than 1000 km in diameter, which orbit the Sun. Also known as minor planets. Thought to be planetesimals leftover from the formation of the planets. The first asteroid (Ceres) was discovered by Giuseppe Piazzi in 1801. More than 10 000 asteroids have so far been discovered and given permanent identification numbers. The largest asteroid is 2001 KX76 with a diameter of at least 1200 km.

ATK - AVIATION TURBINE KEROSENE OR FUEL

The main aviation fuel used for powering aviation gas turbine power units (jet aircraft engine).

ATMOSPHERE

The envelope of gases that surround a planet and are held to it by the planet's gravitational attraction. The Earth's atmosphere is mainly nitrogen and oxygen and is subdivided into four sections: the troposphere- from the earth's surface to an altitude of about 10 km; the stratosphere from 10 km to 50 km; the mesosphere from 50 km to 80 km; and the thermosphere- beyond 80 km.

ATOLL

Circular, or near circular coral reef appearing as a low coral island or a ring of closely spaced coral islets encircling a shallow lagoon in which there is no pre-existing land, and surrounded by deep water of the open sea, formed above an underwater volcano.

ATOM

Atoms are the smallest part of any material that cannot be broken up by chemical means. Each atom has a center (the nucleus) which contains protons and neutrons. Electrons orbit around the nucleus. In an uncharged atom the number of electrons orbiting the nucleus equals the number of protons in the nucleus. The atom is primarily empty space. If the nucleus of an atom was the size of the button on a baseball pitcher's cap, the electrons would be like dust particles revolving around the outside of the baseball stadium at nearly the speed of light.

AUTOECOLOGY

The ecology of an individual species.

AUTOTROPHE

An organism capable of synthesizing its needed organic nutrients from inorganic substances, as carbon dioxide and inorganic nitrogen.