Dictionary

abyssopelagic zone: The zone of the ocean from 4,000m (13,123 feet) to the ocean floor. Absolutely no light can penetrate to this depth.

aphotic zone: A portion of a lake or ocean in which there is little or no sunlight.

bathypelagic zone: The zone of the ocean from 1,000m (3,280 feet) to approximately 4,000m (13,123 feet). The ocean is completely dark at this depth, with no living plants but with the occasional bioluminescent organism.

benthic zone: An ecological region at the lowest level of a body of water, such as an ocean or lake, including the sediment surface and some sub-surface layers.

bioerosion: The erosion of hard ocean substrates by living organisms and a number of other mechanisms.

brackish water: Water that has more salinity than fresh water but not as much as sea water.

cetaceans: A branch of marine science associated with the study of whales, dolphins and porpoises.

coral reefs: Argonite structures produced by living organisms and found in shallow, tropical marine waters with little to no nutrients in the water.

epipelagic zone: A zone of the ocean from the surface down to 200m (656 feet) in which there is enough light for photosynthesis. Many plants and animals are largely concentrated in this zone.