Mudflat

Mudflat
General sketch-map of a tidal plain, showing the typical tripartition in supratidal, intertidal and subtidal zones. The most apparent character of the area is the development of tidal channels, affecting mainly the intertidal zone. In this case, the tidal flat is protected seaward by a beach barrier, but in many cases (low-energy waves and longshore currents) the tidal flats may directly pass into a shallow marine environment.

Mudflats or mud flats, also known as tidal flats, are coastal wetlands that form when mud is deposited by tides or rivers. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries. Mudflats may be viewed geologically as exposed layers of bay mud, resulting from deposition of estuarine silts, clays and marine animal detritus. Most of the sediment within a mudflat is within the intertidal zone, and thus the flat is submerged and exposed approximately twice daily.

In the past tidal flats were considered unhealthy, economically unimportant areas and were often dredged and developed into agricultural land[1]. Several especially shallow mudflat areas, such as the Wadden Sea, are now popular among those practising the sport of mudflat hiking.

Contents

Ecology

Tidal flats, along with intertidal salt marshes and mangrove forests, are important ecosystems.[2] They usually support a large population of wildlife, although levels of biodiversity are not particularly high. They are often of vital importance to migratory birds, as well as certain species of crabs[3], mollusks and fish.[4] In the United Kingdom mudflats have been classified as a Biodiversity Action Plan priority habitat.

The maintenance of mudflats is important in preventing coastal erosion. However, mudflats worldwide are under threat from predicted sea level rises, land claims for development, dredging due to shipping purposes, and chemical pollution.

Selected example areas

Gallery

A panorama of the tidal flat at Cape Henlopen State Park, Delaware, at low tide in January 2009.

See also

References

External links


Wikimedia Foundation. 2010.

См. также в других словарях:

  • mudflat — ► NOUN ▪ a stretch of muddy land left uncovered at low tide …   English terms dictionary

  • mudflat — /ˈmʌdflæt / (say mudflat) noun an area of muddy ground covered by water at high tide …   Australian-English dictionary

  • mudflat — noun Date: 1813 a level tract lying at little depth below the surface of water or alternately covered and left bare by the tide …   New Collegiate Dictionary

  • mudflat — an area of flat muddy land exposed at low tides and a habitat for fishes such as mudskippers …   Dictionary of ichthyology

  • mudflat — mud flat n. Low lying muddy land that is covered at high tide and exposed at low tide. * * * …   Universalium

  • mudflat — noun Coastal wetlands that form when mud is deposited by the tides or rivers, sea, and oceans …   Wiktionary

  • mudflat — mud|flat [ˈmʌdflæt] n [C usually plural] 1.) an area of muddy land that is covered by the sea when it comes up at ↑high tide and uncovered when it goes down at ↑low tide 2.) AmE the muddy bottom of a dry lake …   Dictionary of contemporary English

  • mudflat — n. large flat mound of dirt formed in a river which is exposed by the tide …   English contemporary dictionary

  • mudflat — noun a stretch of muddy land left uncovered at low tide …   English new terms dictionary

  • mudflat — noun (countable often plural) 1 an area of muddy land, covered by the sea when it comes up at high tide and uncovered when it goes down at low tide 2 AmE the muddy bottom of a dry lake …   Longman dictionary of contemporary English


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