BenthosOrganisms living in or on the bottom of a lake, pond, ocean, stream, etc.
Bentonitic clay (bentonite)A clay with a high content of the mineral montmorillonite, usually characterized by high swelling on wetting and shrinkage on drying.
benzeneA chemical that is used widely by the chemical industry, and is also found in tobacco smoke, vehicle emissions, and gasoline fumes.
Bergeron ProcessThe process by which ice crystals in a cloud grow at the expense of supercooled liquid water droplets.
Bergy BitA piece of ice which has broken away from an iceberg, extending 1-5 meters above the sea surface and 100-300 square meters in area.
Berlin MandateA ruling negotiated at the first Conference of the Parties (COP 1), which took place in March, 1995, concluding that the present commitments under the…
BermA horizontal strip or shelf built into an embankment or cut to break the continuity of the slope, usually for the purpose of reducing erosion or to…
Bermuda HighA semi-permanent, subtropical area of high pressure in the North Atlantic Ocean off the East Coast of North America that migrates east and west with…
Best available control measuresThe most effective measures for controlling small or dispersed particulates from sources such as soot and ash from woodstoves and open burning of brush…
Best available control technology (BACT)(BACT)That combination of production processes, methods, systems, and techniques that will result in the lowest achievable level of emissions of air pollutants…
Best gateThe gate opening where the peak efficiency of a turbine occurs at a particular head.
Best Management Practice (BMP)(BMP)A practice or combination of practices that are determined to provide the most effective, environmentally sound, and economically feasible means of…
Best management practices (BMP)(BMP)A practice or combination of practices that a designated agency determines to be the most effective, practical means of reducing the amount of pollution…
Best TrackA subjectively-smoothed representation of a tropical cyclone's location and intensity over its lifetime.
beta particleA high-speed electron or positron, emitted in radioactive decay.
Beta particle (beta radiation, beta ray)An electron of either positive charge (ß+) or negative charge (ß-), which has been emitted by an atomic nucleus or neutron in the process of a…
beta-DNAThe normal form of DNA found in biological systems, which exists as a right-handed helix.
beta-galactosidaseA bacterial enzyme that catalyses the cleavage of lactose into glucose and galactose, commonly used as a marker in DNA cloning.
beta-glucuronidase(Abbreviation: GUS). An enzyme produced by certain bacteria, which catalyses the cleavage of a whole range of beta-glucuronides.
beta-LactamaseAmpicillin resistance gene. (See Selectable marker.)
bias(BY-us) In a scientific research study or clinical trial, a flaw in the study design or the method of collecting or interpreting information.
Bid-ask differential, or spreadThe difference in price between what a buyer offers to pay for a commodity and what a seller offers to accept for a commodity, sometimes referred to as…
BiennialA plant which completes its life cycle within two years and then dies.
BifaceA stone tool that has been flaked on both sides.
Big BangThe scientific theory of the origin of the universe as an explosion of space and matter, starting from an enormously dense and hot state at some finite…
Big gameThose species of large mammals normally managed as a sport-hunting resource.
Bilateral transactionA direct contract between a seller and buyer outside of a centralized market or exchange (e.g. Nymex or an RTO/ISO).
Billing creditIn the Pacific Northwest, a payment by the Bonneville Power Administration to a wholesale customer for actions taken by that customer to reduce BPA´s…
Billow CloudA cloud consisting of broad parallel bands oriented perpendicular to the wind.
BimetalTwo metals of different coefficients of expansion welded together so that the piece will bend in one direction when heated, and in the other when cooled…
Bin MethodA method of predicting heating and/or cooling loads using instantaneous load calculation at different outdoor dry-bulb temperatures, and multiplying the…
Binary CycleCombination of two power plant turbine cycles utilizing two different working fluids for power production.
binary vector systemA two plasmid system in Agrobacterium tumefaciens designed to transfer T-DNA into plant cells, while avoiding the formation of crown gall tumours.
Binder (soil binder)Portion of soil passing a No. 40 (0.425 mm) United States Standard sieve.
bindingThe ability of molecules to bind each other non-covalently because of the exact shape and chemical nature of parts of their surfaces.
BinomialScientific name of plants or animals which has two parts: a genus and a species name.
bio-A prefix used in scientific words to associate the concept of "living organisms.
bio-accumulationA problem that can arise when a stable chemical such as a heavy metal or DDT is introduced into a natural environment.
bio-assay1. The assessment of a substance's activity on living cells or on organisms. Animals have been used extensively in drug research in bio-assays in the…
bio-augmentationIncreasing the activity of bacteria that decompose pollutants; a technique used in bioremediation.
bio-energeticsThe study of the flow and the transformation of energy that occur in living organisms.
bio-engineeringThe use of artificial tissues, organs and organ components to replace parts of the body that are damaged, lost or malfunctioning.
bio-enrichmentAdding nutrients or oxygen to increase microbial breakdown of pollutants.
bio-ethicsThe branch of ethics that deals with the life sciences and their potential impact on society.
bio-informaticsThe use and organization of information of biological interest. In particular, concerned with organizing bio-molecular databases (particularly DNA…
BioaccumulantsSubstances in contaminated air, water, or food that increase in concentration in living organisms exposed to them because the substances are very slowly…
BioassayA study of a living organism to measure the effect of a substance, factor, or condition.
BioassimilationThe accumulation of a substance within a habitat.
BioaugmentationIncreasing the activity of bacteria that decompose pollutants; a technique used in bioremediation.
bioavailabilityThe proportion of a nutrient or administered drug etc. that can be taken up by an organism in a biologically effective form.
Biobased productsFuels, chemicals, building materials, or electric power or heat produced from biological material(s).
biocatalysisThe use of enzymes to improve the efficiency of chemical reactions.
BiochemicalChemical reactions in living organisms.
Biochemical ConversionUsing enzymes and catalysts to change biological substances chemically to produce energy products.
Biochemical conversion processThe use of living organisms or their products to convert organic material to fuels, chemicals or other products.
Biochemical Oxygen DemandThe weight of oxygen taken up mainly as a result of the oxidation of the constituents of a sample of water by biological action; expressed as the number…
Biochemical oxygen demand (BOD)(BOD)A standard means of estimating the degree of water pollution, especially of water bodies that receive contamination from sewage and industrial waste.
Bioconcentration(Bioaccumulation) The accumulation of a chemical in tissues of an organism to levels greater than in the environment in which the organism lives.
biocontrolPest control by biological means. Any process using deliberately introduced living organisms to restrain the growth and development of other organisms…
bioconversionConversion of one chemical into another by living organisms, as opposed to their conversion by isolated enzymes or fixed cells, or by chemical processes.
biodegradeThe breakdown by micro-organisms of a compound to simpler chemicals. Materials that are easily biodegraded are colloquially termed biodegradable.
biodesulphurizationThe removal of organic and inorganic sulphur from coal by bacterial and soil micro-organisms.
BiodieselBiodiesel is diesel fuel combined with a certain percentage of vegetable oil. B5 refers to a blend of diesel with 5% vegetable oil.
BiodiversityThe wide diversity and interrelatedness of earth organisms based on genetic and environmental factors.
BioenergyThe conversion of the complex carbohydrates in organic material into energy.
BioenrichmentAdding nutrients or oxygen to increase microbial breakdown of pollutants.
BiofuelA gaseous, liquid or solid fuel derived from a biological source, e.g. ethanol, rapeseed oil or fish liver oil.
BiofuelsFuels made from biomass. Biofuels include ethanol, biodiesel and methanol.
BiogasA mixture of methane and carbon dioxide resulting from the anaerobic decomposition of waste such as domestic, industrial and agricultural sewage.
Biogenic source (emissions)Biological sources such as plants and animals that emit air pollutants such as volatile organic compounds.
Biogeochemical CycleMovements through the Earth system of key chemical constituents essential to life, such as carbon, nitrogen, oxygen, and phosphorus.
Bioinformatics(BY-oh-in-for-MA-tix) The science of using computers, databases, and math to organize and analyze large amounts of biological, medical, and health…
bioleachingThe recovery of metals from their ores, using the action of micro-organisms, rather than chemical or physical treatment.
biolisticsA technique to generate transgenic cells, in which DNA -coated small metal particles (tungsten or gold) are propelled by various means fast enough to…
Biological assessmentA specific process required as part of an environmental assessment. An evaluation of potential effects of a proposed project on proposed, endangered…
Biological boundariesA concept that differentiates one organism from another and suggests that organisms cannot or should not exchange genetic material.
biological containmentRestricting the movement of organisms from the laboratory. Can take two forms: making the organism unable to survive in the outside environment, or making…