estuary


Also found in: Dictionary, Thesaurus, Medical, Wikipedia.

estuary

(ĕs`cho͝oĕr'ē), partially enclosed coastal body of water, having an open connection with the ocean, where freshwater from inland is mixed with saltwater from the sea. One type of estuary, called a drowned river valley, can be caused by crustal subsidence or a rise in sea level. Chesapeake Bay is one of the largest estuaries of this type in the United States and was formed during the melting of the Pleistocene ice sheets (see Pleistocene epochPleistocene epoch
, 6th epoch of the Cenozoic era of geologic time (see Geologic Timescale, table). According to a classification that considered its deposits to have been formed by the biblical great flood, the epoch was originally called the Quaternary.
..... Click the link for more information.
). Fjordsfjord
or fiord
, steep-sided inlet of the sea characteristic of glaciated regions. Fjords probably resulted from the scouring by glaciers of valleys formed by any of several processes, including faulting and erosion by running water.
..... Click the link for more information.
, or drowned glacial troughs, form similar types of estuaries, particularly in Norway, Alaska, New Zealand, and other glaciated, mountainous coastal regions. Salt marshes and lagoons found behind barrier beaches, such as along the south shore of Long Island, and down faulted sections of the earth's crust, such as San Francisco Bay, are additional types of estuaries. The shape of an estuary affects the height of the tide; some estuaries (such as the Severn and the Bay of Fundy) are characterized by a wavelike tidal borebore,
inrush of water that advances upstream with a wavelike front, caused by the progress of incoming tide from a wide-mouthed bay into its narrower portion. The tidal movement tends to be retarded by friction as it reaches the shallower water and meets the river current; it
..... Click the link for more information.
. Estuaries represent one of the most sensitive and ecologically important habitats on earth. They provide sanctuary for many species of waterfowl, store nutrients for larval and juvenile marine life, and serve as breeding grounds for many desirable species of ocean fish. Since estuaries commonly provide excellent harbors, most of the large ports in the United States (New York, Philadelphia, Baltimore, Mobile, Galveston, Seattle, and San Francisco) are located in estuaries. However, the development of high-density population centers causes deleterious effects that can destroy the very properties of the estuary that made development of the region possible. Human impact on estuaries includes reclamation of tidal land by filling; pollution from sewage, solid waste, industrial effluent, and hot water; increased sedimentation filling the estuary; and alteration of the salinity of estuarine waters by withdrawal or increased influx of freshwater. Increasingly, federal and state governments are passing legislation to protect estuarine environments.

Estuary

 

a single-channel, funnel-shaped seaward end of a river that widens toward the sea. Estuaries form in cases where the sediment carried by the river is removed by sea currents or tidal movements and the adjacent part of the sea is very deep. In such cases no sediment is deposited at the mouth, even if the sediment load is large. The Enisei and the Thames are two of the many rivers that have estuaries.

estuary

[′es·chə ‚wer·ē]
(geography)
A semienclosed coastal body of water which has a free connection with the open sea and within which sea water is measurably diluted with fresh water. Also known as branching bay; drowned river mouth; firth.

estuary

1. the widening channel of a river where it nears the sea, with a mixing of fresh water and salt (tidal) water
2. an inlet of the sea
References in periodicals archive ?
The Orange River Mouth is regarded as the 2nd most important estuary in South Africa in terms of conservation importance, after the Knysna Estuary, and it represents one of four globally important coastal wetlands (the others being Walvis Bay lagoon, Sandwich Harbour and the Kunene River mouth).
Wenliang Wang, Chairman of the China Rilin Industrial Group, for his conservation efforts to restore the Dandong Yalu River Estuary Wetland in China.
Dwindling stock levels on the estuary have resulted in the ban which one cockler says has left fisherman "absolutely gutted".
It has been created to compensate for the loss of natural habitat from construction of the new Redcar coastal flood defences and planned flood defences on the Tees Estuary.
Estuary is within the Lincoln Harbor development, which includes a marina, office space, a Sheraton Suites hotel and restaurants.
Oysters thrive under the variable salinity regime that is a natural component of a healthy estuary (La Peyre et al.
Earlier this year investment company Cluff Natural Resources plc was awarded a licence by the Coal Authority to explore a project to create "syngas" from seams beneath the estuary.
Plans for the first such lagoon are now being drawn up for Swansea Bay in the Severn Estuary, but Liverpool has been identified as one of a number of sites which could also be used for this purpose.
Thirteen buoy stations from the MD are Thachin Estuary, Maeklong Estuary, Banlaem, Bangpakong Estuary, Rayong Estuary, LaemNgob, Prasae, Thachalab, Pakpanang Estuary, Pattani Estuary, Bangnara Estuary, Sichol and Langsuan.
An estuary begins where fresh river water flows into coastal bays and inlets that drain out into the ocean.
TWO children feared stranded in an estuary were rescued by a passing boatman.

Full browser ?