Many organisms use the thick blades as a safe shelter for their young from predators or even rough storms. Among the many mammals and birds that use kelp forests for protection or feeding are seals, sea lions, whales, sea otters, gulls, terns, snowy egrets, great blue herons, cormorants, and shore birds.
These dense canopies of algae generally occur in cold, nutrient-rich waters. Because of their dependency upon light for photosynthesis, kelp forests form in shallow open waters and are rarely found deeper than feet. NOAA scientists study kelp forests by visiting the same locations over and over to assess the presence and abundance of a variety of organisms.
Carbohydrates 9. Thiamin Vit. Riboflavin Vit. Niacin Vit. Pantothenic acid B5 0. Vitamin B6 0. Vitamin C 3. Calcium Iron 2. Magnesium Phosphorus Potassium 89 mg. Sodium mg. Zinc 1. Percentages are relative to US recommendations for adults.
Contents 1 Morphology 2 Growth and reproduction 3 Commercial uses 4 Kelp in history and culture 5 Prominent species 6 Species of Laminaria in the British Isles 7 Species of Laminaria world-wide 8 Other genera in the Laminariales which may be considered as "kelp".
It uses material from the Wikipedia article "Kelp". A list of authors is available in Wikipedia. Fucoxanthin is medically interesting and is under investigation for anticancer and antiinflammatory properties. Plants and chromists store energy differently. Plants store carbohydrates as starch consisting of polymers of glucose. Chromists build laminarin, chains of mannitol and glucose, in organelles called pyrenoids. The cell walls of chromists contain algin, a gum used as a thickener and emulsifier in the food and cosmetics industry.
East Asian cultures have traditionally exploited kelp for food and medicinal value. The rich mineral content of kelp makes it valuable in soil enrichment.
Certain lifestyle features are similar between plants and kelps. One is the alternation of generations between a large diploid sporophyte and a microscopic haploid gametophyte. However seeds are essentially a terrestrial adaptation and kelp have not evolved beyond spores. Like pants, kelp exist as perennials and annuals. Kelps use chemical defenses against grazers as do plants Kelp forests resemble terrestrial forests in their layered structure. At they top is the canopy with blades that reach the surface and beyond.
The understory consists of the smaller kelps that make do with the filtered light that penetrates the canopy.. On one level, the biomechanics of kelp is simple and on another so complex that it continues to elude scientists.
Below this zone, brown algae are found. These include bladderwrack and knotted wrack, which rely on gas-filled pods for buoyancy and to stay upright in the water.
Below the brown algae, red algae occur in the lowest intertidal zone, and far below them come the large kelp species such as blade kelp or sea tangle.
Every algae zone is a distinct habitat type, with a typical assemblage of flora and fauna species. The sessile algae comprise green algae, which also occur in freshwater, as well as the almost exclusively marine brown and red algae. These have a worldwide distribution and, running counter to the general trend, they also occur in temperate and cold waters in an abundance of different species.
As far as is known, the north-west Pacific and the tropical and subtropical western Atlantic seem to be particularly species-rich, while southern Australia has a large number of endemic species, i. In wide areas of the temperate and subarctic regions, hard seafloors below the low-tide line are covered in growth of very large brown algae, in jungle-like kelp forests.
Originally the term 'kelp' was applied to seaweed ash, which was used in the 19th century as a source of soda, potash and iodine, among other elements.
Later, the term was extended to algae of the genera Macrocystis, Nereocystis and Laminaria themselves. Where the algae reach to the water surface they are known as kelp forests.
If submerged, they are called kelp beds. Typically they are found in the cold currents of the Atlantic and Pacific. Occasionally, they also occur in tropical waters, in upwelling regions where cold deep water is pushed to the surface.
But there are also free-floating seaweed jungles. The largest and best known of these is the Sargasso Sea, an area of the Atlantic spanning approximately 8 million square kilometres, east of the Gulf of Mexico.
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