Alaria
Encyclopedia
Alaria is a genus of brown alga (Phaeophyceae) comprising approximately 17 species. Members of the genus are dried and eaten as a food
Food
Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals...

 in Western Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

, Korea
Korea
Korea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...

, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 (called sarumen), and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 17:56, 1 August 2010 (UTC). Distribution of the genus is a marker for climate change, as it relates to oceanic temperatures.

The most common species, Alaria esculenta is a large brown seaweed
Seaweed
Seaweed is a loose, colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae...

 common on the shores of the British Isles
British Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...

. It has been studied for its potential for aquaculture
Aquaculture
Aquaculture, also known as aquafarming, is the farming of aquatic organisms such as fish, crustaceans, molluscs and aquatic plants. Aquaculture involves cultivating freshwater and saltwater populations under controlled conditions, and can be contrasted with commercial fishing, which is the...

.

Description

Alaria is a genus of highly variable brown algae
Brown algae
The Phaeophyceae or brown algae , is a large group of mostly marine multicellular algae, including many seaweeds of colder Northern Hemisphere waters. They play an important role in marine environments, both as food and for the habitats they form...

, and a member of the order Laminariales, more commonly known as kelp
Kelp
Kelps are large seaweeds belonging to the brown algae in the order Laminariales. There are about 30 different genera....

. It has mature sporophytes as small as 15 centimetres (5.9 in) and as large at 15 metres (49.2 ft) in length. All species’ sporophytes consist of a ramified holdfast
Holdfast
A holdfast is a root-like structure that anchors aquatic sessile organisms, such as seaweed, other sessile algae, stalked crinoids, benthic cnidarians, and sponges, to the substrate. ...

, an unbranched stipe
Stipe (botany)
In botany, a stipe is a stalk that supports some other structure. The precise meaning is different depending on which taxonomic group is being described....

, and a blade with a percurrent, cartilaginous midrib.Alaria is frequently found with lacerations running from the margin to the midrib caused by the ravages of the sea.

Taxonomy

Alaria the second largest genus of Laminariales, with about 17 currently recognized species. However, due to its highly plastic morphology, the kelp has over 100 specific and subspecific names, which have arisen since it was first described in 1830. These synonyms have been tailored down to the present species through genetic comparisons.

Biogeographical

Alaria is most commonly found in far northern waters of the Pacific and Atlantic oceans, with the greatest variety of species concentrated in the north Pacific. More specifically, it has been found on the coasts of England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

, Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

, Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

, Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...

, Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...

, Denmark
Denmark
Denmark is a Scandinavian country in Northern Europe. The countries of Denmark and Greenland, as well as the Faroe Islands, constitute the Kingdom of Denmark . It is the southernmost of the Nordic countries, southwest of Sweden and south of Norway, and bordered to the south by Germany. Denmark...

, Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...

, Japan, China, Korea, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

.

Ecological

Alaria is typically found in the sublittoral zones, at a depth of 3–10 m (9.8–32.8 ). An important factor in Alaria’s distribution is temperature; it is limited by sea temperature of 16°C. and greater. Presumably due to this factor, and rising sea temperatures, the genus has largely disappeared from the English Channel
English Channel
The English Channel , often referred to simply as the Channel, is an arm of the Atlantic Ocean that separates southern England from northern France, and joins the North Sea to the Atlantic. It is about long and varies in width from at its widest to in the Strait of Dover...

 within the past 100 years. Recent research conducted on Alaria esculenta in the Arctic
Arctic
The Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...

 showed pronounced temperature effects on the photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

 and germination of the algae.

Human consumption

In Ireland, Scotland, Greenland, Iceland, Denmark, and the Faroe Islands
Faroe Islands
The Faroe Islands are an island group situated between the Norwegian Sea and the North Atlantic Ocean, approximately halfway between Scotland and Iceland. The Faroe Islands are a self-governing territory within the Kingdom of Denmark, along with Denmark proper and Greenland...

, the midrib is removed, and the blade and sometimes the leaflets are eaten, although it is not commercially available. It is more commonly eaten in the Far East (China, Japan, and Korea), where seaweed consumption is much more popular than in the West. Seaweeds are considered to be highly nutritious, because typically they are low in fat, and have vitamins and minerals in amounts comparable or superior to terrestrial vegetables. Alaria esculenta, in particular, is an excellent source of protein and iodine.

Life history

As with all kelps, Alaria demonstrate a heteromorphic, sporic life history, with a macroscopic, dominant sporophyte, and a microscopic gametophyte. Unique to the genus Alaria is that the sori of the unilocular sporangia are restricted to certain blades, the sporophylls. The sporophylls are formed as lateral blades from the stipe. Most species are perennial; after reproduction, the blade sloughs off, leaving the stipe and meristem. The persisting meristem produces a new blade at the beginning of the next growing season.

Also known as...

  • “Badderlocks”, “Dabberlocks” or “Henware” in Scotland proper
  • “Honey-ware” in the Orkney Islands (Northern Scotland)
  • “Murlins” in Ireland
  • “Wing kelp” unknown origin
  • "California nori"
  • "Wild nori"
  • "California wakame"

Species

The species currently recognised are:
  • A. angusta
  • A. crassifolia, sarumen, ezo-wakame
  • A. crispa
  • A. dolichorhachis
  • A. elliptica
  • A. esculenta
  • A. fragilis
  • A. grandifolia
  • A. marginata
  • A. oblonga
  • A. paradisea
  • A. praelonga
  • A. pylaiei

External links

  • Images of Alaria at Algaebase
    AlgaeBase
    AlgaeBase is a global species database of information on all groups of algae, as well as one group of flowering plants, the sea-grasses.AlgaeBase evolved from Michael Guiry's seaweed website, and has grown into a database of algae from throughout the world, and in freshwater, terrestrial, and...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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