key words enviro

• Abiotic factors


  Physical factors such as light, temperature and water
• Acidification


  A process in which the pH drops as the conditions become more acidic
• Acidophile


  An organism that thrives under acidic conditions. Many acidophiles are bacteria or archaea
• Acoustic deterrent devices


  A device that deters mammals by using sound. They are used to deter small cetaceans from fishing nets, or seals from fish farms, for example
• Acoustic fatigue


  Stress cracking of a material caused by repetitive vibrations induced by sound
• Acoustic monitoring


  Monitoring environmental sounds eg to detect the presence of dolphins and whales or bats
• Activated carbon filter


  A filter that reduces emissions of pollutants such as complex organic molecules that adsorb onto the surface of the activated carbon particles
• Activation products


  Atomic nuclei that become radioactive because they have absorbed neutrons that change them into less stable nuclei that emit ionising radiation
• Active traffic management (ATM)


  A method of controlling road lane usage and speed limits to smooth traffic flow and reduce congestion
• Acute


  Exposure to a substance or symptoms that appear rapidly
• Adsorption


  The process where a substance fixes onto a surface
• Aerobic process


  A process that takes place in the presence of oxygen
• Aerodynamics


  The study of airflow over surfaces to allow the design of surfaces that reduce wind resistance, turbulence, friction and noise generation
• Afforestation


  Planting trees to increase the area of forest
• Albedo


  A measure of the reflectivity of a surface. More reflective surfaces have high albedos. A surface that reflects all light has an albedo of 100%, while one that absorbs all light has an albedo of 0%. The albedo of an area can affect the local climate
• Anaerobic process


  A process that takes place in the absence of oxygen
• Antarctic Treaty (1959)


  An international agreement signed by many countries to protect and manage Antarctica. Aspects of the treaty include control of military activities, waste disposal, mineral exploitation, wildlife conservation and tourism
• Anthropogenic


  Adjective describing outcomes caused by human activities
• Aphotic zone


  Deeper layers of water that receive no sunlight because they are absorbed by shallower layers
• Aquaculture


  The artificial production of aquatic organisms, including fish farming
• Aquifer


  A rock which contains water that is abstracted by humans
• Archaea


  Microorganisms similar to bacteria, including the first life-forms to develop on Earth. Archaea are the only organisms that produce methane from the decomposition of organic matter
• Artificial insemination


  A form of selective breeding where semen is collected from a chosen male to be inserted artificially into the chosen female to cause her to become pregnant. It also allows semen to be stored for later use or the transport of semen without having to bring the animals together
• As low as reasonably achievable (ALARA)

  An approach to control of pollution, especially ionising radiation, where levels are kept as low as is practically achievable, taking into account economic and technological factors
• Atmosphere


  The gases surrounding the Earth. Different layers are characterised by their temperature, density, turbulence and composition
• Baffle mounds


  Embankments that absorb and deflect noise, especially around mines, airports and major roads
• Bag filter


  A method reducing atmospheric pollution caused by smoke and particulate matter
• Barrage


  A dam built across an estuary to generate tidal power
• Barrier crops


  A crop that is grown around another crop to protect the neighbouring crop, usually by producing a scent that deters the pests
• Beating tray


  A method of sampling invertebrates on the branches of bushes and small trees
• Becquerel (Bq)


  The Becquerel is the unit of activity of a radioactive source. 1 Bq = I nuclear decay per second. It is usually related to a standard mass of material
• Best available technology not entailing excessive cost (BATNEEC)


  An approach to pollution control where control technology is used that achieves the lowest emission levels, without costing so much that further marginal gains would risk their financial viability
• Bioaccumulation


  The increase in concentration of a substance in living tissue as it is absorbed and stored faster than it is broken down and excreted
• Biocapacity


  A measure of the biological productivity of an area
• Biodegradable


  A material that can be broken down by living organisms, usually bacteria
• Biodiversity


  A measure of the variety and abundance of wildlife species. A common quantitative method of measuring biodiversity is Simpson's Diversity Index
• Biogeochemical cycle


  A series of linked processes which use and re-use elements such as carbon, nitrogen, phosphorus, iron and sulfur, as they move between biotic and abiotic reservoirs
• Bioleaching


  A method of using bacteria to dissolve metals from low grade ores
• Biological control


  The control of pests using living organisms, usually predators or pathogens
• Biological corridor


  A habitat that links other habitats so that animals can move between them