calcareous	Containing, or resembling, calcium carbonate (CaCO3); chalky.
calcium carbonate	A white, crystalline salt occuring in limestone, chalk and pearl. Used in the production of lime. Formula CaCO3 .
Capitella capitata	A polychaete worm widely associated with polluted conditions. Often used as an indicator species in biological monitoring.
carbon dioxide	Colourless, odourless, incombustible gas present in the atmosphere and formed during respiration. (CO2 ).
carcinogen	Any substance that produces cancer.
carnivore	An organism that eats meat. Most carnivores are animals, but some fungi, plants, and protists may be too.
Cd (cadmium)	A malleable bluish-white metallic element that occurs in association with zinc ores. Used in electroplating and alloys. Symbol: Cd. Atomic number: 48.
chemical reaction	Any reaction involving changes to atoms or molecules.
chitin	A polysaccharide that is the principal component of the exoskeleton of arthropods and of the bodies of fungi.
chloride	Any salt of hydrochloric acid, containing the chlorine ion Cl-2 . any compound containing a chlorine atom, such as methyl chloride, CH3 Cl.
chlorine	The chemical element often used as a biocide in the cooling waters of power plants and as a disinfectant.
chromatography	The technique of separating and analysing the components of a mixture of liquids or gases by selective adsorption.
chronic pollution	1. Prolonged; referring to a process occurring over a period of weeks, months or years. 2. An extended exposure to a stressor (conventionally taken to include at least a tenth of the life span of a species), or the effects resulting from such an exposure.
cilia	Hairlike outgrowths capable of whip-like beating movements.
clay	A very fine-grained material that occurs as sedimentary rocks, soils and other deposits. Becomes plastic when wet but hardens on drying.
coast	The line or zone where the land meets the sea.
coast morphology	The form and structure of a coast.
coastal zone	The term coastal zone means the coastal waters (including the lands therein and thereunder) and the adjacent shorelands (including the waters therein and thereunder), strongly influenced by each and in proximity to the shorelines of the several coastal states, and includes islands, transitional and inter-tidal areas, salt marshes, wetlands, and beaches.
colonise	To become established in a new environment.
community	Any group of organisms belonging to a number of different species that co-occur in the same habitat or area and interact through trophic and spatial relationships; typically characterized by reference to one or more dominant species.
compensation depth	1. The depth of water at which photosynthetic oxygen production is balanced by respiratory uptake. The compensation depth is generally assumed to correlate with the depth at which light is 1% of its incident intensity. Below this depth there will be no net phytoplankton growth. For practical purposes the compensation depth can be taken to represent the lower limit of the photic zone 2. The term is also used to describe the ocean depth at which the rate of solution of calcium carbonate increases to the point that dissolution of calcareous shells begins; typically a depth of about 4000m, below which calcareous sediments are not found.
competition	The simultaneous demand by two or more organisms or species for an essential common resource that is actually or potentially in limited supply (exploitation competition), or the detrimental interaction between two or more organisms or species seeking a common resource that is not limited (interference competition).
concentration	The strength of a solution, especially the amount of dissolved substance in a given volume of solvent.
consumer	An organism that feeds on another organism or existing organic matter, including herbivores, carnivores, parasites, saprophytic and heterotrophic organisms.
continental shelf	The submerged top of the continent's edge between the shoreline and the continental slope. The shelf is made more shallow by deposition of material eroded from the land. The shelf has a gentle slope (1 degree) and is the shallowest portion of the ocean.
continental slope	The narrow, steep (3 deg. to 6 deg. gradient) transition zone between the shallow shelf and the deep ocean floor. Sedimentary material on the continental slope is very unstable because of the steep gradient.
convection	The process by which masses of relatively warm air are raised into the atmosphere, often cooling and forming clouds, with compensatory downward movements of cooler air.
convention	1. A large formal assembly of a group with common interests 2. An international agreement second only to a treaty in formality.
Coriolis effect	The deflection of air or water bodies, relative to the solid earth beneath, as a result of the earth's eastward rotation.
crude oil	Unrefined petroleum - a complex mixture of hydrocarbons with 4-26 or more carbon atoms in the molecule.
crustacean	Any arthropod of the mainly aquatic class Crustacea, typically having a carapace and including lobsters, crabs and water fleas.
Cu (copper)	A malleable reddish metallic element occurring as the free metal copper glance, and copper pyrites: used in alloys as brass and bronze. Symbol: Cu, Atomic number: 29.
cytoplasm	The protoplasm of a cell excluding the nucleus.