AQA Subject Specific Vocabulary

Abiotic factors

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. 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. Higher = more reflective surface. 100% = reflects all light, 0% = absorbs all light. Can affect 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 = 1 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. Simpson’s Diversity Index is used to quantify this.

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.

Biomagnification

The progressive bioaccumulation of a material along a food chain eg organochlorine insecticides, PCBs, heavy metals.

Biomass

The total mass of living, or recently living material in an area.

Biome

A large geographical region with particular climatic features, in which a characteristic, unique community of species lives eg Taiga, coral reefs, temperate grasslands, tundra, tropical rainforest. Don’t confuse the terms biome and ecosystem. Biome refers to the total area where the community of species is found, whereas ecosystem refers to a particular community and its interactions. So, there are many tropical rainforest ecosystems but only one biome.

Biomimetics

The study of living organisms so the knowledge gained can be applied to engineering or other technological developments.

Bioremediation

Cleaning up a contaminated site using living organisms such as bacteria that chemically degrade the pollutants or plants that absorb the pollutants.

Biotic index

A measure of pollution based on the presence, abundance and state of health of selected living organisms eg lichens for acid rain, aquatic invertebrates for water pollution.

Blue baby syndrome/Methaemoglobinaemia

A health problem with several possible causes, where the haemoglobin in a baby’s blood does not carry enough oxygen. Nitrates in drinking water can be converted to nitrites which reduce the ability of haemoglobin to carry oxygen.

Bund wall

A wall that surrounds a tank which would contain the contents if the tank leaked or burst.

Bycatch

The non-target organisms that are caught when fishing.

Captive breeding and release programmes (CBR)

A method of boosting wild populations by keeping a breeding population in captivity. Some of the offspring produced may be released to join the wild population.

Carbon capture and storage (CCS)

A method to reduce carbon dioxide emissions, by removing the gases and storing them in underground geological structures.

Carbon footprint

An estimate of the total releases of greenhouse gases caused by the actions of an individual, group of people, an organisation or activity. The amounts of all greenhouse gases are expressed as the equivalent amount of carbon dioxide.

Carbon sequestration

Any process which removes carbon dioxide from the atmosphere, such as afforestation or underground storage (carbon capture).

Carcinogen

A substance or energy form that can cause cancer.

Carrying capacity

The greatest population that can be supported sustainably in an area.

Catalytic converter

A device that reduces emissions of pollutant gases from petrol and diesel engines. Catalysts such as platinum, palladium and rhodium catalyse reactions with oxides of nitrogen, carbon monoxide and unburnt hydrocarbons.

Catch quota

A limit on the quantity of fish that can be caught.

Centre of diversity

A geographical region with a high plant biodiversity, especially of the wild relatives of crop species.

Cetaceans

Marine mammals including whales, dolphins and porpoises.

Compact fluorescent lamp (CFL)

An early design of low-energy light.

Chronic

Exposure to a substance or symptoms that appear over long periods of time.

Cirrus cloud

Thin, wispy clouds, usually found at altitudes above 6000m. Can reflect infrared energy emitted by the Earth’s surface and emit infrared produced from absorbed sunlight.

Clean Air Act (1956)

UK legislation to control smoke pollution by the establishment of Smoke Zones by making Control Orders in large urban areas.

Climax community

The relatively stable community of species present at the end of ecological succession.

Cloning

An artificial form of asexual reproduction.

Cnidarians

A taxon of animals that includes corals and jellyfish.

Colonisation media

A method of demonstrating the presence of species by providing places that they can colonise which can then be checked.

Combined heat and power station (CHP)

A power station that has a high overall energy efficiency because the heat energy from the condenser cooling water is harnessed and used, often for heating buildings.

Community of species

A community of species is made up of the populations of all the species living in a particular area.

Companion crops

These are crops that are grown together to benefit one or both crops by actions such as providing nutrients, controlling pests or attracting beneficial insects.

Concentrating solar power (CSP)

A method of increasing the intensity of solar energy by using a parabolic array of mirrors to reflect the light onto a smaller area.

Constant descent angle

A method of approaching an airport where the aircraft descends at a constant angle, usually 3°.

Contact action (pesticide)

A pesticide that kills pests by coming in contact with them after spraying. Unlike systemic pesticides, they are not absorbed and translocated around the crops.

Contamination

Pollution caused by the pollutant staying in contact or mixing with materials such as soil, atmosphere, water or living organisms.

Contour ploughing

A soil erosion control measure where land is cultivated by ploughing horizontal furrows along the contours of the land.

Convention on international trade in endangered species (CITES)

International agreement that controls the international trade in certain species of plants and animals and their products.

Cooling towers

A method of reducing the temperature of effluent water to reduce thermal pollution and deoxygenation.

Coppicing

The process of regularly cutting down tree branches close to ground level. The regrowth produces thin straight branches. It was traditionally done on a cycle of six to ten years for making fence panels and wall panels. Short-rotation willow coppice is now used as a biofuel.

Cradle to cradle design (C2C)

The concept of designing items such that all the materials used can be reused or disposed of without leaving toxic or harmful wastes. The concept is based on the natural systems that recycle elements without depleting resources or causing harmful wastes to build up.

Critical group monitoring

A method of monitoring pollutants, particularly radioactive discharges. If the members of the public that are most at risk are safe, then so is everyone else.

Critical pathway analysis (CPA)

The prediction of the routes that an effluent will take in the environment, to assess pollution risk.

Crop rotation

The practise of growing a different crop in a field on a cycle of three, four or five years.

Crop wild relatives (CWRs)

These are wild plant varieties or species that are closely related to domesticated crops. CWRs may contain genetic characteristics that can be used in crop breeding programmes.

Cryosphere

All the frozen water on Earth.

CSS

Countryside Stewardship Scheme.

Culling

Reducing the population of a species by selective killing.

Cut-off ore grade

The lowest purity of a mineral that can be exploited economically.

Cyclone separator

Equipment used to remove suspended particles from gaseous effluents.

DAFOR scale

A qualitative scale that judges the abundance of organisms. Initials stand for: Dominant, Abundant, Frequent, Occasional, Rare.

dB scale

A logarithmic scale used to measure sound levels.

Debt for nature swaps

These are agreements whereby an organisation agrees to pay part of a country’s debt in return for a commitment to a wildlife conservation programme.

Decomposers

Organisms that break down dead organic matter, releasing nutrients in the process. Many bacteria and fungi are decomposers. They secrete enzymes onto the dead organic matter and absorb the products of digestion.

Deflected succession

Natural ecological succession is stopped by human actions. Long-term continuation of the actions that deflect succession will create a plagioclimax.

Deforestation

The action of removing trees, resulting in a reduction in forest area.

Degradability

A measure of the ease with which a material breaks down.

Demersal

Living on the seabed eg cod, plaice.

Dendrochronology

The method of determining the age of a piece of wood using the characteristic sequence of sizes of growth rings in the wood.

Desulfurisation

The removal of sulfur or compounds containing sulfur such as sulfur dioxide.

Detritivores

These are heterotrophic animals that ingest and digest dead organic matter, including earthworms, millipedes, woodlice, dung beetles and slugs. They often break up the dead organic matter into smaller pieces, providing access to decomposers.

Directional drilling

The drilling of wells for oil or gas that are not vertical.