A lagoon is a shallow body of water separated from a larger body of water by a narrow landform , such as reefs , barrier islands , barrier peninsulas, or isthmuses . Lagoons are commonly divided into coastal lagoons (or barrier lagoons ) and atoll lagoons . They have also been identified as occurring on mixed-sand and gravel coastlines. There is an overlap between bodies of water classified as coastal lagoons and bodies of water classified as estuaries . Lagoons are common coastal features around many parts of the world.
21-580: Wainono Lagoon is a shallow lagoon in the southern Canterbury region of New Zealand 's South Island . A number of rivers flow into the lagoon, including the Hook River from the north and the Waihao River from the south. Nearby settlements include Hook and Studholme , with the town of Waimate approximately eight kilometres west. Although it is within metres of the Pacific Ocean ,
42-539: A lake is hu ( 湖 ), and a lagoon is xihu ( 潟湖 ). In the French Mediterranean several lagoons are called étang ("lake"). Contrariwise, several other languages have specific words for such bodies of water. In Spanish, coastal lagoons generically are laguna costera , but those on the Mediterranean coast are specifically called albufera . In Russian and Ukrainian, those on
63-422: A regular flow of fresh water an "estuary". Davis does state that the terms "lagoon" and "estuary" are "often loosely applied, even in scientific literature". Timothy M. Kusky characterizes lagoons as normally being elongated parallel to the coast, while estuaries are usually drowned river valleys, elongated perpendicular to the coast. Coastal lagoons are classified as inland bodies of water. When used within
84-580: Is brackish with a variable salinity: during periods of low fresh-water intake, wide-mouthed, deep examples will be greatly saline from inflow of sea water and evaporation. Such features are found in places with low tidal range , for example along the western and northern coast of the Black Sea , in the Baltic Sea ( Vistula Lagoon , the Curonian Lagoon ), as well as along the lowest part of
105-458: Is actually the third-largest lake by area in the country. The brackish water lagoon may be thus explicitly identified as a "coastal lagoon" ( laguna costera ). In Portuguese, a similar usage is found: lagoa may be a body of shallow seawater, or a small freshwater lake not linked to the sea. Lagoon is derived from the Italian laguna , which refers to the waters around Venice ,
126-570: The Black Sea are liman ( лиман ), while the generic word is laguna ( Лагуна ). Similarly, in the Baltic , Danish has the specific Nor [ da ] , and German the specifics Bodden and Haff , as well as generic terms derived from laguna . In Poland these lagoons are called zalew ("bay"), in Lithuania marios ("lagoon, reservoir"). In Jutland several lagoons are known as fjord . In New Zealand
147-883: The Danube . Examples of limans include Lake Varna in Bulgaria , Lake Razelm in Romania , the Dniester Liman in Ukraine and the Anadyrskiy Liman and Amur Liman in Siberia . English borrows the word from Russian : лиман , romanized : liman ( Russian pronunciation: [lʲɪˈman] ), taken from the Turkish : liman spread by Turks when they occupied the western and northern shore of
168-523: The Māori word hapua refers to a coastal lagoon formed at the mouth of a braided river where there are mixed sand and gravel beaches, while waituna , an ephemeral coastal waterbody, is neither a true lagoon, lake nor estuary. Some languages differentiate between coastal and atoll lagoons. In French, lagon [ fr ] refers specifically to an atoll lagoon, while coastal lagoons are described as étang [ fr ] ,
189-562: The Razelm liman . A liman can be maritime (the bar being created by the current of a sea) or fluvial (the bar being created by the slowed or turned flow of a sediment-saturated river). The term describes many wet estuaries in the Black Sea and the Sea of Azov ; a synonymous term guba (губа) is used in Russian sources for estuaries of the Russian shores in the north. Water in a liman
210-610: The Venetian Lagoon . Laguna is attested in English by at least 1612, and had been Anglicized to "lagune" by 1673. In 1697 William Dampier referred to a "Lagune or Lake of Salt water" on the coast of Mexico. Captain James Cook described an island "of Oval form with a Lagoon in the middle" in 1769. Atoll lagoons form as coral reefs grow upwards while the islands that the reefs surround subside, until eventually only
231-458: The Wadden Sea , have strong tidal currents and mixing. Coastal lagoons tend to accumulate sediments from inflowing rivers, from runoff from the shores of the lagoon, and from sediment carried into the lagoon through inlets by the tide. Large quantities of sediment may be occasionally be deposited in a lagoon when storm waves overwash barrier islands. Mangroves and marsh plants can facilitate
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#1732786641001252-610: The Wainono Lagoon is fresh water and separated from the sea by a gravel berm . Tests have revealed that the level of the lagoon does not fluctuate with the tide and its level of salinity is low. Fresh water, however, seeps from the lagoon into the sea. The Department of Conservation (DOC) has established the Wainono Lagoon Conservation Area to protect the natural environment of the lagoon. The Waitangi Tribunal in 1995 directed DOC to develop
273-409: The accumulation of sediment in a lagoon. Benthic organisms may stabilize or destabilize sediments. Liman (landform) A liman ( Russian : лиман ; Romanian : liman ) is an enlarged estuary formed as a lagoon at the wide mouth of one or several rivers , where flow is nearly fully or partially constrained by a mouth bar of sediments ( peresyp ), as in the Dniester Liman or
294-626: The context of a distinctive portion of coral reef ecosystems, the term "lagoon" is synonymous with the term "back reef" or "backreef", which is more commonly used by coral reef scientists to refer to the same area. Many lagoons do not include "lagoon" in their common names. Currituck , Albemarle and Pamlico Sounds in North Carolina , Great South Bay between Long Island and the barrier beaches of Fire Island in New York , Isle of Wight Bay , which separates Ocean City, Maryland from
315-597: The generic word for a still lake or pond. In Vietnamese, Đầm san hô refers to an atoll lagoon, whilst Đầm phá is coastal. In Latin America, the term laguna in Spanish, which lagoon translates to, may be used for a small fresh water lake in a similar way a creek is considered a small river. However, sometimes it is popularly used to describe a full-sized lake , such as Laguna Catemaco in Mexico, which
336-651: The lagoon as a traditional fishery resource with Ngāi Tahu . Lagoon Lagoons are shallow, often elongated bodies of water separated from a larger body of water by a shallow or exposed shoal , coral reef , or similar feature. Some authorities include fresh water bodies in the definition of "lagoon", while others explicitly restrict "lagoon" to bodies of water with some degree of salinity . The distinction between "lagoon" and "estuary" also varies between authorities. Richard A. Davis Jr. restricts "lagoon" to bodies of water with little or no fresh water inflow, and little or no tidal flow, and calls any bay that receives
357-630: The lagoon. Lagoons with little or no interchange with the open ocean, little or no inflow of fresh water, and high evaporation rates, such as Lake St. Lucia , in South Africa , may become highly saline. Lagoons with no connection to the open ocean and significant inflow of fresh water, such as the Lake Worth Lagoon in Florida in the middle of the 19th century, may be entirely fresh. On the other hand, lagoons with many wide inlets, such as
378-556: The land along the coast). Coastal lagoons do not form along steep or rocky coasts, or if the range of tides is more than 4 metres (13 ft). Due to the gentle slope of the coast, coastal lagoons are shallow. A relative drop in sea level may leave a lagoon largely dry, while a rise in sea level may let the sea breach or destroy barrier islands, and leave reefs too deep underwater to protect the lagoon. Coastal lagoons are young and dynamic, and may be short-lived in geological terms. Coastal lagoons are common, occurring along nearly 15 percent of
399-407: The reefs remain above sea level. Unlike the lagoons that form shoreward of fringing reefs, atoll lagoons often contain some deep (>20 m (66 ft)) portions. Coastal lagoons form along gently sloping coasts where barrier islands or reefs can develop offshore, and the sea-level is rising relative to the land along the shore (either because of an intrinsic rise in sea-level, or subsidence of
420-627: The rest of Worcester County, Maryland , Banana River in Florida , US, Lake Illawarra in New South Wales , Australia, Montrose Basin in Scotland , and Broad Water in Wales have all been classified as lagoons, despite their names. In England, The Fleet at Chesil Beach has also been described as a lagoon. In some languages the word for a lagoon is simply a type of lake: In Chinese
441-522: The world's shorelines. In the United States, lagoons are found along more than 75 percent of the Eastern and Gulf Coasts . Coastal lagoons can be classified as leaky, restricted, or choked. Coastal lagoons are usually connected to the open ocean by inlets between barrier islands. The number and size of the inlets, precipitation, evaporation, and inflow of fresh water all affect the nature of
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