Floating island
Encyclopedia
A floating island is a mass of floating aquatic plants, mud, and peat ranging in thickness from a few inches to several feet. Floating islands are a common natural phenomenon that are found in many parts of the world. They exist less commonly as a man-made phenomenon
Artificial island
An artificial island or man-made island is an island or archipelago that has been constructed by people rather than formed by natural means...

. Floating islands are generally found on marshlands, lake
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...

s, and similar wetland locations, and can be many hectare
Hectare
The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

s in size.

Natural occurrences

Sometimes referred to as tussocks, floatons, or suds, natural floating islands are composed of vegetation growing on a buoyant mat of plant roots or other organic detritus. Some cenote
Cenote
A cenote is a deep natural pit, or sinkhole, characteristic of Mexico and Central America, resulting from the collapse of limestone bedrock that exposes groundwater underneath...

s in northern Mexico have natural floating islands.

They typically occur when growths of cattail
Typha
Typha is a genus of about eleven species of monocotyledonous flowering plants in the family Typhaceae. The genus has a largely Northern Hemisphere distribution, but is essentially cosmopolitan, being found in a variety of wetland habitats...

s, bulrush
Schoenoplectus
Schoenoplectus is a genus of about 80 species of sedges with a cosmopolitan distribution. Note that the name bulrush is also applied to species in the unrelated genus Typha...

, sedge
Cyperaceae
Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...

, and reed
Phragmites
Phragmites, the Common reed, is a large perennial grass found in wetlands throughout temperate and tropical regions of the world. Phragmites australis is sometimes regarded as the sole species of the genus Phragmites, though some botanists divide Phragmites australis into three or four species...

s extend outward from the shoreline of a wetland area. As the water gets deeper the roots no longer reach the bottom, so they use the oxygen in their root mass for buoyancy, and the surrounding vegetation for support to retain their top-side-up orientation. The area beneath these floating mats is exceptionally rich in aquatic lifeforms. Eventually, storm events tear whole sections free from the shore, and the islands thus formed migrate around a lake with changing winds, eventually either reattaching to a new area of the shore, or breaking up in heavy weather.

Natural floating islands may have been the source of many "disappearing island" legend
Legend
A legend is a narrative of human actions that are perceived both by teller and listeners to take place within human history and to possess certain qualities that give the tale verisimilitude...

s, such as those surrounding Avalon
Avalon
Avalon is a legendary island featured in the Arthurian legend. It first appears in Geoffrey of Monmouth's 1136 pseudohistorical account Historia Regum Britanniae as the place where King Arthur's sword Excalibur was forged and later where Arthur was...

.

Explosive volcanic eruptions may create pumice raft
Pumice raft
A pumice raft is a floating raft of pumice occasionally created by ocean-based volcanic activity.Volcanic activity in the South Pacific near Tonga on August 12, 2006 caused the emergence of a new island...

s, which can float on the ocean for months or even years before becoming fully saturated and sinking. Over time, larger rafts can have grasses and palm trees growing on them.

Artificial islands

Floating artificial island
Artificial island
An artificial island or man-made island is an island or archipelago that has been constructed by people rather than formed by natural means...

s are generally made of bundled reeds, and the best known examples are those of the Uros
Uros
The Uros are a pre-Incan people who live on forty-two self-fashioned floating islands in Lake Titicaca Puno, Peru and Bolivia. They form three main groups: Uru-Chipayas, Uru-Muratos and the Uru-Iruitos...

 people of Lake Titicaca
Lake Titicaca
Lake Titicaca is a lake located on the border of Peru and Bolivia. It sits 3,811 m above sea level, making it the highest commercially navigable lake in the world...

, Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

, who build their villages upon what are in effect huge rafts of bundled totora
Totora (plant)
Totora is a subspecies of the giant bulrush sedge. It is found in South America - notably on Lake Titicaca, the middle coast of Perú and on Easter Island in the Pacific Ocean...

 reeds. The Uros originally created their islands to prevent attacks by their more aggressive neighbours, the Incas and Collas. The Aztec
Aztec
The Aztec people were certain ethnic groups of central Mexico, particularly those groups who spoke the Nahuatl language and who dominated large parts of Mesoamerica in the 14th, 15th and 16th centuries, a period referred to as the late post-classic period in Mesoamerican chronology.Aztec is the...

 capital, Tenochtitlan, was surrounded with chinampa
Chinampa
Chinampa is a method of ancient Mesoamerican agriculture which used small, rectangle-shaped areas of fertile arable land to grow crops on the shallow lake beds in the Valley of Mexico.-Description:...

s
, small artificial islands used for agriculture known as "floating gardens" (though not really floating). Spiral Island
Spiral Island
Spiral Island is a name given to two floating artificial islands in Mexico built by British artist Richart "Rishi" Sowa. The first was destroyed by a hurricane in 2005; the second has been open for tours since 2008....

 was a more modern one-person effort to build an artificial floating island, on the Caribbean coast of Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

.

The British wartime Project Habakkuk
Project Habakkuk
Project Habakkuk or Habbakuk was a plan by the British in World War II to construct an aircraft carrier out of pykrete , for use against German U-boats in the mid-Atlantic, which were beyond the flight range of land-based planes at that time.The idea came from Geoffrey Pyke who worked for Combined...

 proposed the construction of aircraft carrier
Aircraft carrier
An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...

s made of ice-like Pykrete
Pykrete
Pykrete is a composite material made of approximately 14 percent sawdust or some other form of wood pulp and 86 percent ice by weight. Its use was proposed during World War II by Geoffrey Pyke to the British Royal Navy as a candidate material for making a huge, unsinkable aircraft carrier...

. Its size and speed made it more of an artificial iceberg
Iceberg
An iceberg is a large piece of ice from freshwater that has broken off from a snow-formed glacier or ice shelf and is floating in open water. It may subsequently become frozen into pack ice...

 or island than a ship.

Commercial development of floating islands has begun taking place. A commercially-produced floating island was installed in the river otter enclosure at Zoo Montana in 2007. In 2009 and the beginning of 2010, a few larger islands were launched to provide nesting habitat for Caspian Tern
Caspian Tern
The Caspian Tern is a species of tern, with a subcosmopolitan but scattered distribution. Despite its extensive range, it is monotypic of its genus, and has no subspecies accepted either...

 colonies. The largest of the islands, at a record-setting 44000 sq ft (4,087.7 m²), was launched into the water at Sheepy Lake. These islands are a collaboration between the United States Army Corps of Engineers
United States Army Corps of Engineers
The United States Army Corps of Engineers is a federal agency and a major Army command made up of some 38,000 civilian and military personnel, making it the world's largest public engineering, design and construction management agency...

, Oregon State University
Oregon State University
Oregon State University is a coeducational, public research university located in Corvallis, Oregon, United States. The university offers undergraduate, graduate and doctoral degrees and a multitude of research opportunities. There are more than 200 academic degree programs offered through the...

, and Floating Islands West, a Floating Island International license holder.

A company called Floating Islands International licenses technology for creating floating islands to a variety of organizations.

Floating Island Environmental Solutions, a company based out of Baton Rouge, Louisiana create floating islands constructed from matrix sheets, derived from non-woven 100% recycled PET plastic
Polyethylene terephthalate
Polyethylene terephthalate , commonly abbreviated PET, PETE, or the obsolete PETP or PET-P, is a thermoplastic polymer resin of the polyester family and is used in synthetic fibers; beverage, food and other liquid containers; thermoforming applications; and engineering resins often in combination...

 which mimic naturally occurring wetlands.

Locations

  • Lake Titicaca
    Lake Titicaca
    Lake Titicaca is a lake located on the border of Peru and Bolivia. It sits 3,811 m above sea level, making it the highest commercially navigable lake in the world...

    , Bolivia and Peru
  • Lake Kyoga
    Lake Kyoga
    Lake Kyoga is a large shallow lake complex of Uganda, about in area and at an elevation of 914 m. The Victoria Nile flows through the lake on its way from Lake Victoria to Lake Albert. The main inflow from Lake Victoria is regulated by the Nalubaale Power Station in Jinja. Another source of water...

    , Uganda
  • Loktak Lake
    Loktak Lake
    Loktak Lake, the largest freshwater lake in India, also called the only Floating lake in the world due to the floating phumdis on it, is located near Moirang in Manipur state, India. The etymology of Loktak is Lok = "stream" and tak = "the end"...

    , India
  • Umbagog Lake, Maine, United States
  • Island Pond, Massachusetts, United States
  • Lake Visitor, Montenegro
  • Vlasina Lake
    Vlasina Lake
    Vlasina Lake is a semi-artificial lake in Southeast Serbia. Lying at the altitude of 1211 m, with the area of 16 km², it is the highest and largest artificial lake in Serbia...

    , Serbia
  • Lake Upemba
    Lake Upemba
    Lake Upemba is a lake in Bukama, Haut-Lomami District, the Democratic Republic of the Congo. It, and nearby Lake Kisale, is surrounded by the Upemba Depression in Upemba National Park...

    , Democratic Republic of the Congo
  • Lake Chad
    Lake Chad
    Lake Chad is a historically large, shallow, endorheic lake in Africa, whose size has varied over the centuries. According to the Global Resource Information Database of the United Nations Environment Programme, it shrank as much as 95% from about 1963 to 1998; yet it also states that "the 2007 ...

    , Africa
  • Inle Lake
    Inle Lake
    Inle Lake is a freshwater lake located in the Nyaungshwe Township of Taunggyi District of Shan State, part of Shan Hills in Myanmar . It is the second largest lake in Myanmar with an estimated surface area of , and one of the highest at an altitude of...

    , Burma (Myanmar)
  • Prairie Lake, Barron County, Wisconsin, United States
  • Prashar Lake
    Prashar Lake
    Prashar Lake lies 49 km north of Mandi, with a three storied pagoda-like temple dedicated to the sage Prashar. The Lake is located at a height of 2730 m above sea level. With deep blue waters, the lake is held sacred to the sage Prashar and he is regarded to have meditated there...

    , Mandi, Himachal pradesh, India

External links

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