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Definition: lagoon from The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide

Coastal body of shallow salt water, usually with limited access to the sea. The term is normally used to describe the shallow sea area cut off by a coral reef or barrier islands.


Summary Article: Lagoon
from The Encyclopedia of Tourism and Recreation in Marine Environments

A lagoon is a shallow stretch of coastal water that is completely or partly separated from the open sea by a narrow strip of land, usually formed by sand, shingle, mud or reef. Lagoons may be tidal or seasonal, as when a lagoon consisting of a stretch of water enclosed by coral or sandbanks becomes open water at either a high tide or following high-magnitude events, such as storms, that alter coastal sediment systems. Lagoons are also associated with tropical marine environments through the creation of lagoons by coral reefs, in which the lagoon is the description of the body of water between the reef and the mainland or island, where it is referred to as an atoll. Where coral reefs are associated with lagoons, it is possible to distinguish between the narrow and shallow lagoons of a fringing reef that is close to shore and the wider and deeper lagoons that are established between the coast and a barrier reef that is much further from the shore.

Lagoons are environmentally significant because the relative calm of the water provides opportunities for species to breed, as well as providing a different environmental niche to open water. This relative calm is also of value for tourism, because it offers both safe bathing as well as nature-based tourism opportunities. In the developed world many lagoons are suffering increased environmental stress through pollution and over-use, with lagoons in urban areas often having been substantially modified for coastal housing and industrial development.

C. Michael Hall
© CAB International 2008.

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