Estuaries and coastal waters are among the most productive ecosystems on Earth, providing numerous ecological, economic, cultural, and aesthetic benefits and services.

An estuary is a semi-enclosed coastal body of water which has a free connection with the open sea and within which sea water mixes with fresh water. The key feature of an estuary is that it is a mixing place for sea water and a significantly-sized river to supply fresh water. A tide is a necessary component to maintain a dynamic relationship between the two waters. Though something in the nature of an estuary can exist in a non-tidal sea, such areas go by names such as lagoon, étang or laguna. In non-tidal seas, the rivers naturally form deltas rather than estuaries. Wikipedia does not have an article with this exact name. ... Water (from the Old English word wæter; c. ... Sunset at sea Look up Sea on Wiktionary, the free dictionary Look up maritime in Wiktionary, the free dictionary. ... Sea water is water from a sea or ocean. ... For the village on the Isle of Wight, see Freshwater, Isle of Wight. ... The tide is the regular rising and falling of the oceans surface caused by changes in gravitational forces external to the Earth. ... Nile River delta, as seen from Earth orbit. ...

An estuary is typically the tidal mouth of a river, and estuaries are often characterised by sedimentation of silt which usually comes mainly from the sea though in some cases, that from the river predominates. The sand and mud banks and marshes are relied upon as habitat by, for example, wading birds. Estuaries are more likely to occur on submerged coasts, where the sea level has risen in relation to the land, as this process floods valleys to form rias, fords etc, which can be classified as estuaries in cases where there is a significant river flowing into them. The Murray River in Australia. ... Sediment is any particulate matter that can be transported by fluid flow and which eventually is deposited as a layer of solid particles on the bed or bottom of a body of water or other liquid. ... Silt refers to soil or rock particles of a certain very small size range (see grain size). ... Freshwater marsh in Florida In geography, a marsh is a type of wetland, featuring grasses, rushes, reeds, typhas, sedges, and other herbaceous plants (possibly with low-growing woody plants) in a context of shallow water. ... Habitat (from the Latin for it inhabits) is the place where a particular species lives and grows. ... Families Charadridae Jacanidae Rostratulidae Ibidorhynchidae Recurvirostridae Haematopodidae Scolopacidae Dromadidae Burhinidae Glareolidae Thinocoridae Waders, called Shorebirds in North America (where wader is used to refer to long-legged wading birds such as storks and herons), are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. ... For other meanings of bird, see bird (disambiguation). ... Fljótsdalur in East-Iceland A valley is a landform, which can range from a few square miles (square kilometers) to hundreds or even thousands of square miles (square kilometers) in area. ... Port Hacking, in the southern suburbs of Sydney (Australia) is a ria, or drowned river valley. ... Ford may mean a number of things: A ford is a river crossing. ...

The estuaries are sometimes confused with fjords. The Lim bay in Istria, Croatia (Limski kanal in Croatian), is often called "Lim fjord" although it was not actually formed by glacial erosion but by the river Pazinčica. Sognefjorden, Norway A fjord (sometimes written fiord, notably in New Zealand English) is a glacially overdeepened valley, usually narrow and steep-sided, extending below sea level and filled with salt water. ... The Lim bay and valley is a peculiar geographic feature found near Rovinj and Vrsar on the western coast of Istria, Croatia, south of Poreč. The name comes from the Latin limes for limit, referring to the landforms position at the border of two Roman provinces (Dalmatia and Italia). ... Rovinj, on the western coast of Croatian Istria. ...

Estuary is also a term used to describe the region of the Thames River and adjoining communities east of Central London in the United Kingdom. The term 'Estuary English' is frequently used to describe the accent of the people in this region, though it has since spread across South East England. It is sometimes mistaken for the Cockney accent by listeners unfamiliar with the varieties. Several places exist with the name Thames, and the word is also used as part of several brand and company names Most famous is the River Thames in England, on which the city of London stands Other Thames Rivers There is a Thames River in Canada There is a Thames... Charing Cross is taken as Londons most central place when measuring distances. ... Estuary English is a name given to the form of English widely spoken in South East England, especially along the river Thames and its estuary. ... South East England is one of the official regions of England. ... A Cockney, in the loosest sense of the word, is a working-class inhabitant of the East End of London. ...

See also

• Brackish water
• Category:Estuaries
• Firth
• List of waterways
• Chesapeake Bay

Brackish water is water that is saltier than fresh water, but not as salty as sea water. ... Firth is the Scots word used to denote various coastal waters in Scotland. ... The List of waterways is a link page for any river, canal, estuary or firth. ... Chesapeake Bay - Landsat photo The Chesapeake Bay is the largest estuary in the United States. ...

References

• Pritchard, D. W. (1967) What is an estuary: physical viewpoint. p. 3–5 in: G. H. Lauf (ed.) Estuaries, A.A.A.S. Publ. No. 83, Washington, D.C.