Definitions - b

Background Extinction Rate

The natural rate of extinction for a species. Contrasts sharply with Mass Extinction.

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Background Level

The average amount of a substance present in the environment. Originally referring to naturally occurring phenomena. Used in toxic substance monitoring.

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Bactericide

A pesticide used to control or destroy bacteria, typically in the home, schools, or hospitals.

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Bamboo
Bamboo

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Barra System

The Barra system is a passive solar building technology developed by Horazio Barra in Italy. It uses a collector wall to capture solar radiation in the form of heat. It also uses the thermosiphon effect to distribute the warmed air through channels incorporated into the reinforced concrete floors, warming the floors and hence the building. Alternatively, in hot weather, cool nighttime air can be drawn through the floors to chill them in a form of air conditioning.

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Base Load

The average amount of electric power that a utility must supply in any period.

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Basel Convention

The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal is an international agreement governing the handling of hazardous and other wastes.

Signed by 172 nations, the Convention has been in force since 1992 and makes it illegal to ship hazardous or landfill waste from one country for in another. It does not cover waste designated for recycling, which can be exported for processing abroad.

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Baseline Emissions

The emissions that would occur without policy intervention (in a business-as-usual scenario). Baseline estimates are needed to determine the effectiveness of emissions reduction programs (often called mitigation strategies).

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Benefical Organism

In agriculture and gardening, a beneficial organism is any organism that benefits the growing process, including insects, arachnids, other animals, plants, bacteria, fungi, viruses, and nematodes. Benefits include pest control, pollination, and maintenance of soil health. The opposite of beneficial organisms are pests, which are organisms deemed detrimental to the growing process.

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Benzene

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Beryllium

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Betz Coefficient

59.3 percent - the theoretical maximum efficiency at which a wind generator can operate, by slowing the wind down. If the wind generator slows the wind down too much, air piles up in front of the blades and is not used for extracting energy.

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Bioaccumulants

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Bioassay

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Biochar
Biochar

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Bioconcentration

The accumulation of a chemical in tissues of an organism to levels greater than in the environment in which the organism lives.

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Biocontrol

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Biodegradable

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Biodegradable Pollutants

Pollutants that are capable of decomposing under natural conditions.

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Biodiesel

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Biodiversity

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Biodynamic Argiculture

A type of organic farming founded by Rudolf Steiner. It advocates treating a farm or garden as a unified ecological system, the use of mixtures of fermented herbs and minerals as soil additives, and following an astronomical calendar for planting and sowing.

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Bioethanol

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Biofilm

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Biofuel

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Biogas

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Biogeochemical Cycle

Global warming is the name given to the theory that there is increase in the average temperature of the Earth surface air and oceans since the mid-20th century and its projected continuation.

The exact mechanism of warming is not precisely understood, although it is strongly suspected that Greenhouse gases are to blame, as increasing concentrations of such gases help trap heat in the atmosphere and so raise mean temperatures.

Wikipedia Entry

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Biological Oxygen Demand

Amount of dissolved oxygen needed by aerobic decomposers to break down the organic materials in a given volume of water at a certain temperature over a specified time period.

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Biological Pest Control

a method of controlling pests (including insects, mites, weeds and plant diseases) that relies on predation, parasitism, herbivory, or other natural mechanisms.

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Biological Treatment

Technology that uses bacteria to consume waste/ organic materials.

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Biomagnification

The cumulative increase in the concentrations of a persistent substance in successively higher levels of the food chain.

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Biomass

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Biomass Energy

Energy produced by combusting biomass materials such as wood. The carbon dioxide emitted from burning biomass will not increase total atmospheric carbon dioxide if this consumption is done on a sustainable basis (i.e., if in a given period of time, regrowth of biomass takes up as much carbon dioxide as is released from biomass combustion). Biomass energy is often suggested as a replacement for fossil fuel combustion.

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Biome

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Biophotolysis

The action of light on a biological system that results in the dissociation of a substrate, usually water, to produce hydrogen.

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Biophysical

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Biopiracy

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Bioregion

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Bioremediation

A process using organisms to remove or neutralise contaminants (e.g. petrol), mostly in soil or water.

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Biosolids

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Biosphere

In essence the Biosphere is all the ecosystems that exist in a planet. Including how they interact, evolve and change over time.

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Bioswale

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Biota

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Biotechnology

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Biotransformation

Conversion of a substance into other compounds by organisms; including biodegradation.

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Bisphenol-a

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Black Body

In theory, a body that absorbs and emits 100% of the electromagnetic radiation that strikes it and therefore appears black. Graphite comes close, with all but 3% absorption.

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Blackwater

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Bladder Tank

A bladder tank is basically a 'bag' made from reinforced PVC tarpaulin to hold water. These are often used under houses or buildings in the sub floor space to store rain water for use with irrigation or general water supply (such as for flushing toilets or washing clothes). Sizes vary from as little as 2000 litres up to 5000 litres

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Bleached Board

A wood product used for printed and graphically enhanced card stock, books, and packaging such as food cartons, microwave trays, beverages, candy, cosmetics, pharmaceuticals, and consumer electronic items. Pollutants, such as dioxins and furans, can result from processes that use chlorine in the manufacture of bleached board.

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Bliss Point

In the formulation of food products, the bliss point is the amount of an ingredient such as salt, sugar, or fat which optimizes palatability. 


Pioneering work on the bliss point was carried out by American market researcher and psycho-physicist Howard Moskowitz, known for his successful work in product creation and optimization for foods ranging from spaghetti sauce to soft drinks. Moskowitz describes the bliss point as "that sensory profile where you like food the most".

The bliss point is now extensively used by the food manufacturing business to maximize the tendency for certain foods to be habit forming or 'addictive' in their appeal.

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Blown In Insulation

There are numerous ways to add a layer of insulation between your interior living spaces and the outside world. Blown-in insulation (also called blown-in batt) is composed of loose insulating fibers such as fiberglass, foam, or cellulose. While rolled or batt insulation might leave voids through which air can pass, blown-in types tend to fill all crevices, making it a more energy-efficient choice.

Blown-in insulation is generally installed by a professional.

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Body Burden

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Boreal

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Borehole

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Boron

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Bottle Bank

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Box Schemes

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Brackish Water

Mixed fresh and salt water.

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Brakedrum Windmill

A home-built wind generator design by Hugh Piggott of Scotland.

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Breakpoint Chlorination

Addition of chlorine to water until there is enough chlorine present for disinfection of water.

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Bright Green

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Brominated Flame Retardants

Chemicals added to plastics, textiles, furniture foam and padding, and other products to prevent them from catching fire. BFRs, as they are known, are long-lived poisons that build up in fat. In animal studies, they have been linked to hormonal and neurological disorders.

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Brown Goods

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Brown Search

A brown search refers to the act of looking for information on recycling and sustainability on the internet. Most 'green' search engines are also able to perform this function as they will index such sites (as the EcoWho search engine does).

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Buckwheat

A plant cultivated for its triangular grains, which are protected by a hull. This crop is generally grown without herbicides and pesticides.

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Building Envelope

The entire perimeter of a building enclosed by its roof, walls and foundation. Properly designed, the envelope can minimize temperature gain or loss and moisture infiltration.

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Building Orientation

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Building Paper

Also called building felt or housewrap; used in the construction of frame houses to block drafts and moisture. Building paper is applied in layers over a house’s walls and sheathing, with the top courses overlapping the bottom courses so that water drains off the wall.

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Building-Related Illness

Serious and diagnosable health conditions, usually of the respiratory system, that can be attributed to specific air quality problems within a building.

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Bycatch

The accidental harvest of one organism instead of another, such as crustaceans caught in shrimp trawls and dolphins trapped instead of tuna.

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A free Android app containing all these definitions is now available, called the Green Dictionary. Click here to see the entry on the Android market; or click here if on an Android phone.