Is seaweed a form of algae?
Seaweed
Seaweed or macroalgae refers to several species of macroscopic, multicellular, marine algae. The term includes some types of red, brown, and green macroalgae. Marine algae species such as kelps provide essential nursery habitat for fisheries and other marine species and thus protect food sources; ocean algae species from seaweeds to planktons play a vital role in carbon capture, producing up to 90 percent of the planet's oxygen. Understanding these roles provides guiding principles for conservation and sustainable use of seaweeds to take precedence over industrial exploitation. Mechanical dredging of kelp, for instance, destroys the resource and dependent fisheries. Certain species of seaweed are valuable for nutrition, biomedicine, bioremediation, and other uses.
Wakame
In Old Japanese, "me" stood for edible seaweeds in general as opposed to "mo" standing for algae. In kanji, such as 海藻, 軍布 and 和布 were applied to transcribe the word. Among seaweeds, wakame was likely most often eaten, therefore "me" especially meant wakame. It expanded later to other seaweeds like kajime, hirome (kombu), arame, etc. Wakame is derived from "waka" + "me" (若布, lit. young seaweed). If this "waka" is a eulogistic prefix, same as the "tama" of tamagushi, wakame likely stood for seaweeds widely in ancient ages. In Man'yōshū, in addition to 和可米 and 稚海藻 (both are read as "wakame"), "nigime" (和海藻, soft wakame) can be seen. Besides, "tamamo" (玉藻, lit. beautiful algae), which often appeared in Man'yo-shu, may be wakame depending on poems.
Northern Ireland
Algae/seaweed.
356 species of marine algae have been recorded in the north-east of Ireland. As Counties Londonderry, Antrim and Down are the only three counties of Northern Ireland with a shoreline this will apply to all Northern Ireland. 77 species are considered rare having been recorded rarely.
Seaweed
The following table lists a very few example genera of seaweed.
Algae
The singular "alga" is the Latin word for "seaweed" and retains that meaning in English. The etymology is obscure. Although some speculate that it is related to Latin "algēre", "be cold", no reason is known to associate seaweed with temperature. A more likely source is "alliga", "binding, entwining".
Sargassum
Sargassum is a genus of brown (class Phaeophyceae) macroalgae (seaweed) in the order Fucales. Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit shallow water and coral reefs, and the genus is widely known for its planktonic (free-floating) species. Most species within the class Phaeophyceae are predominantly cold-water organisms that benefit from nutrients upwelling, but the genus "Sargassum" appears to be an exception. Any number of the normally benthic species may take on a planktonic, often pelagic existence after being removed from reefs during rough weather; however, two species ("S. natans" and "S. fluitans") have become holopelagic—reproducing vegetatively and never attaching to the seafloor during their lifecycles. The Atlantic Ocean's Sargasso Sea was named after the algae, as it hosts a large amount of "Sargassum".
Cruoriaceae
Cruoriaceae is a family of crustose red algae – that is, a seaweed.
Bryopsis plumosa
Bryopsis plumosa, sometimes known by the common names green algae or hen pen, is a type of green seaweed.
Seaweed
Seaweeds are also used as animal feeds. They have long been grazed by sheep, horses and cattle in Northern Europe. They are currently particularly valuable for fish production. Adding seaweed to livestock feed can substantially reduce methane emissions from cattle.
Rotting seaweed is a potent source of hydrogen sulfide, a highly toxic gas, and has been implicated in some incidents of apparent hydrogen-sulphide poisoning. It can cause vomiting and diarrhea.
Brown algae
Many algae have a flattened portion that may resemble a leaf, and this is termed a "blade", "lamina", or "frond". The name "blade" is most often applied to a single undivided structure, while "frond" may be applied to all or most of an algal body that is flattened, but this distinction is not universally applied. The name "lamina" refers to that portion of a structurally differentiated alga that is flattened. It may be a single or a divided structure, and may be spread over a substantial portion of the alga. In rockweeds, for example, the lamina is a broad wing of tissue that runs continuously along both sides of a branched "midrib". The midrib and lamina together constitute almost all of a rockweed, so that the lamina is spread throughout the alga rather than existing as a localized portion of it.
In some brown algae, there is a single lamina or blade, while in others there may be many separate blades. Even in those species that initially produce a single blade, the structure may tear with rough currents or as part of maturation to form additional blades. These blades may be attached directly to the stipe, to a holdfast with no stipe present, or there may be an air bladder between the stipe and blade. The surface of the lamina or blade may be smooth or wrinkled; its tissues may be thin and flexible or thick and leathery. In species like "Egregia menziesii", this characteristic may change depending upon the turbulence of the waters in which it grows. In other species, the surface of the blade is coated with slime to discourage the attachment of epiphytes or to deter herbivores. Blades are also often the parts of the alga that bear the reproductive structures.
Desmarestia viridis
Desmarestia viridis is a species of brown algae found worldwide. Its common names include stringy acid kelp, green acid kelp, Desmarest's green weed, and sea sorrel, though the last name can refer to other species of "Desmarestia". The light brown thallus is delicate with a disc-shaped holdfast. It releases sulfuric acid when damaged, destroying itself and nearby seaweeds in the process. They are found in shallow intertidal areas.
Leafy seadragon
The lobes of skin that grow on the leafy seadragon provide camouflage, giving it the appearance of seaweed. It is able to maintain the illusion when swimming, appearing to move through the water like a piece of floating seaweed. It can also change colour to blend in, but this ability depends on the seadragon's diet, age, location, and stress level.
Posidonia australis
Posidonia australis is a species of seagrass that occurs in the southern waters of Australia. It is sometimes referred to as fibreball weed. The marine plant forms large meadows that are considered to be of high importance to the environmental conservation of the region. Balls of decomposing detritus from the foliage of the plant are found along nearby shore-lines.
Seaweed
The development of seaweed as an alternative and sustainable source of food and animal feed ingredients depends on the sustainability of the natural resource of raw biomass and on moving the process of feed development from laboratory to industrial scale.
Brown algae
Regardless of size or form, two visible features set the Phaeophyceae apart from all other algae. First, members of the group possess a characteristic color that ranges from an olive green to various shades of brown. The particular shade depends upon the amount of fucoxanthin present in the alga. Second, all brown algae are multicellular. There are no known species that exist as single cells or as colonies of cells, and the brown algae are the only major group of seaweeds that does not include such forms. However, this may be the result of classification rather than a consequence of evolution, as all the groups hypothesized to be the closest relatives of the browns include single-celled or colonial forms.
Algae fuel
Research into algae for the mass-production of oil focuses mainly on microalgae (organisms capable of photosynthesis that are less than 0.4 mm in diameter, including the diatoms and cyanobacteria) as opposed to macroalgae, such as seaweed. The preference for microalgae has come about due largely to their less complex structure, fast growth rates, and high oil-content (for some species). However, some research is being done into using seaweeds for biofuels, probably due to the high availability of this resource.The amount of oil each strain of algae produces varies widely. Note the following microalgae and their various oil yields:In addition, due to its high growth-rate, "Ulva" has been investigated as a fuel for use in the "SOFT cycle", (SOFT stands for Solar Oxygen Fuel Turbine), a closed-cycle power-generation system suitable for use in arid, subtropical regions.
Seaweed blenny
The seaweed blenny is native to shallow waters in the western Atlantic Ocean. Its range extends from New York southwards to Brazil, and includes the Caribbean Sea, the Gulf of Mexico, Bermuda and the Bahamas at depths down to about . A typical habitat is among limestone boulders and in scoops and basins where the rock surface is covered with a mat of algae, sea fans and other invertebrates. It is also found on reefs, in seagrass meadows and oyster beds, as well as around man-made structures such as pilings, jetties, seawalls, oil rigs and buoys, and among the roots of mangroves.
Pylaiella
Pylaiella (mung) is a genus of seaweed (brown algae) that can be a nuisance due to its ability to coat people, ropes, animals, and more when it blooms close to the shore under particular conditions.
Phycodrys rubens
"Phycodrys rubens" is seaweed which is perennial and can grow to 30 cm long and is strongly red in colour. It grows with flat leaf-like blades which are monostromatic, that is composed of a single flat layer of cells and can grow 3 cm wide. These blades can become 3 cm wide and show a clear mid-rib. The blades have a ruffled margin with veins growing out from the central mid-rib with paired lateral veins. The plants grow from a small disk holdfast with an axis to the blades.
The algae are somewhat similar to "Delesseria sanguinea" which is also strongly red but has a smooth, not dentate, margin. The shape of the frond is similar to the leaf of an Oak tree.
Alaria (alga)
In Ireland, Scotland, Greenland, Iceland, Denmark, and the Faroe Islands, 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.
Algae
The spores of freshwater algae are dispersed mainly by running water and wind, as well as by living carriers. However, not all bodies of water can carry all species of algae, as the chemical composition of certain water bodies limits the algae that can survive within them. Marine spores are often spread by ocean currents. Ocean water presents many vastly different habitats based on temperature and nutrient availability, resulting in phytogeographic zones, regions, and provinces.
Algae
Some parasitic algae (e.g., the green algae "Prototheca" and "Helicosporidium", parasites of metazoans, or "Cephaleuros", parasites of plants) were originally classified as fungi, sporozoans, or protistans of "incertae sedis", while others (e.g., the green algae "Phyllosiphon" and "Rhodochytrium", parasites of plants, or the red algae "Pterocladiophila" and "Gelidiocolax mammillatus", parasites of other red algae, or the dinoflagellates "Oodinium", parasites of fish) had their relationship with algae conjectured early. In other cases, some groups were originally characterized as parasitic algae (e.g., "Chlorochytrium"), but later were seen as endophytic algae. Some filamentous bacteria (e.g., "Beggiatoa") were originally seen as algae. Furthermore, groups like the apicomplexans are also parasites derived from ancestors that possessed plastids, but are not included in any group traditionally seen as algae.
Fucus gardneri
Fucus gardneri is a species of seaweed, a brown alga living on the littoral shore of the Pacific coasts of North America. It has the common names of rockweed and bladderwrack.
Ascophyllum
Ascophyllum nodosum is a large, common cold water seaweed or brown alga (Phaeophyceae) in the family Fucaceae, being the only species in the genus Ascophyllum. It is a seaweed that only grows in the northern Atlantic Ocean, also known in localities as feamainn bhuí, rockweed, Norwegian kelp, knotted kelp, knotted wrack or egg wrack. It is common on the north-western coast of Europe (from Svalbard to Portugal) including east Greenland and the north-eastern coast of North America, its range further south of these latitudes being limited by warmer ocean waters.
Lemnoideae
Duckweed is an important high-protein food source for waterfowl.The tiny plants provide cover for fry of many aquatic species. The plants are used as shelter by pondwater species such as bullfrogs and fish such as bluegills. They also provide shade and, although frequently confused with them, can reduce certain light-generated growths of photoautotrophic algae. Duckweed is also eaten by humans in some parts of Southeast Asia. As it contains more protein than soybeans, it is sometimes cited as a significant potential food source. Some initial investigations to what extent duckweed could be introduced in European markets show little consumer objection to the idea.
Suaeda nigra
Suaeda nigra (formerly Suaeda moquinii) is a species of flowering plant in the amaranth family known by the common names Mojave sea-blite and bush seepweed.
Vanvoorstia bennettiana
Vanvoorstia bennettiana (Bennett's seaweed) is an extinct red alga from Australia. It is named after naturalist George Bennett.
Caulerpa sertularioides
The seaweed has a pale to dark-green thallus that typically grows to outward to around . It has feather-like fronds that arise from a common stolon. Each of the fronds is upright and branched. The opositely arranged branchlets are cylindrical to needle-shaped with upcurved tips with a blunt point at the end. Each branchlet has a length of and is attached to a cylindrical axis in the middle with a diameter of . Each axis connects each frond to a creeping stolon with a diameter of and a length of up to . Stolons are branched out to slim points and rhizoids then form from bottom surface these fork and penetrate the sandy substrate firmly anchoring the seaweed to the seafloor.
Phycology
Algae are important as primary producers in aquatic ecosystems. Most algae are eukaryotic, photosynthetic organisms that live in a wet environment. They are distinguished from the higher plants by a lack of true roots, stems or leaves. They do not flower. Many species are single-celled and microscopic (including phytoplankton and other microalgae); many others are multicellular to one degree or another, some of these growing to large size (for example, seaweeds such as kelp and "Sargassum").
Algae
The Ancient Greek word for seaweed was φῦκος ("phŷcos"), which could mean either the seaweed (probably red algae) or a red dye derived from it. The Latinization, "fūcus", meant primarily the cosmetic rouge. The etymology is uncertain, but a strong candidate has long been some word related to the Biblical פוך ("pūk"), "paint" (if not that word itself), a cosmetic eye-shadow used by the ancient Egyptians and other inhabitants of the eastern Mediterranean. It could be any color: black, red, green, or blue.
Seaweed fertiliser
Seaweed fertiliser, also spelled seaweed fertilizer, is seaweed that is collected and used as an organic fertilizer.
Sea foam
Foams can form following the degradation of harmful algal blooms (HABs). These are primarily composed of algal species, but can also consist of dinoflagellates and cyanobacteria. Biomass from algae in the bloom is integrated into sea foam in the sea surface microlayer. When the impacted sea foam breaks down, toxins from the algae are released into the air causing respiratory issues and occasionally initiating asthma attacks. "Phaeocystis globosa" is one algal species that is considered problematic, as observed in a study in the Netherlands. Its high biomass accumulation allows it to create large quantities of toxic foam that often wash onto beaches. "P. globosa" blooms are initiated in areas of high nutrient availability, often affiliated with coastal locations with a lot of stormwater runoff and eutrophication. Studies suggest that the development of foam is directly correlated to blooms caused by "P. globosa", despite that foam formation typically occurs approximately two weeks after the appearance of an algal bloom offshore. Organic material from "P. globosa" was observed decomposing while suspended at the sea surface, but was not observed lower in the water column. "P. globosa" is also considered a nuisance species because its large foam formations impair the public's ability to enjoy the beach.
Seaweed cultivator
A seaweed cultivator is a device which grows seaweed, usually in weekly or bi-weekly cycles. It is not to be confused with people who are seaweed cultivators themselves, usually performing manual cultivation of seaweed using large nets in open waters (mainly in Asian countries).
Stipe (botany)
A stipe is also a structure found in organisms that are studied by botanists but that are no longer classified as plants. It may be the stem-like part of the thallus of a mushroom or a seaweed, and is particularly common among brown algae such as kelp. The stipe of a kelp often contains a central region of cells that, like the phloem of vascular plants, serves to transport nutrients within the alga.
Alginic acid
Seaweeds can be classified into three broad groups based on pigmentation: brown, red and green. These broad groups are the Phaeophyceae, Rhodophyceae and Chlorophyceae, respectively. Brown seaweeds are usually large, and range from the giant kelp "Macrocystis pyrifera" that is often 20 m long, to thick, leather-like seaweeds from 2–4 m long, to smaller species 30–60 cm long. None of the usual seaweeds for alginate production are cultivated. They cannot be grown by vegetative means, but must go through a reproductive cycle involving an alternation of generations. This makes cultivated brown seaweeds too expensive when compared to the costs of harvesting and transporting wild seaweeds. The only exception is for "Laminaria japonica", which is cultivated in China for food but the surplus material is diverted to the alginate industry in China.
Callithamnion roseum
Callithamnion roseum is a type of red algae (a red seaweed).
Laverbread
Laverbread () is a food product, made from an edible seaweed (littoral alga), consumed mainly in Wales as part of local traditional cuisine. The seaweed is commonly found around the west coast of Great Britain and east coast of Ireland along the Irish Sea, where it is known as slake. It is smooth in texture and forms delicate, sheetlike thalli, often clinging to rocks. The principal variety is porphyra ("Porphyra umbilicalis"). Porphyra (laver seaweed) is classified as red algae; it tends to be a brownish colour, but boils down to a dark green pulp when prepared. Laver seaweed has a high content of dietary minerals, particularly iodine and iron. The high iodine content gives the seaweed a distinctive flavour in common with olives and oysters.
Arame
It is one of many species of seaweed used in Asian cuisine.
Zostera muelleri
Seagrasses are a flowering plant species, not to be confused with seaweed, which do not form flowers, fruits, and seeds to reproduce. Seagrasses are important to the marine ecosystem for many reasons. For one, they provide food, homes, and breeding grounds to a variety of marine species. Secondly, meadows of seagrass are important carbon reservoirs or sinks, sequestering 10-18% of the ocean's carbon accumulation for long-term storage. Seagrasses also enhance sediment accretion, and protect coastlines from destructive wave energy.
Agriculture in Australia
The shorelines, especially the Great Barrier Reef, are providing motivation to help the continent by using seaweed (algae) to absorb nutrients. Because of the giant number of natural Australian seaweeds, not only could seaweed cultivation be used to help absorb nutrients around the GBR and other Australian shores, cultivation could also help feed a large part of the world. Even the Chinese, who could be considered far more advanced in seaweed cultivation, are interested in the future of Australian seaweeds. Lastly, the GBR itself, because of the delicate corals, has lent itself to utilizing seaweed/algae purposely as a nutrient reduction tool in the form of algae. This has occurred in the form of algae scrubbers, and seaweed cultivators, which are now available for domestic use worldwide.
Laminaria digitata
Laminaria digitata is a large brown alga in the family Laminariaceae, also known by the common name Oarweed. It is found in the sublittoral zone of the northern Atlantic Ocean.
Sea
Marine primary producers — plants and microscopic organisms in the plankton — are widespread and very essential for the ecosystem. It has been estimated that half of the world's oxygen is produced by phytoplankton. About 45 percent of the sea's primary production of living material is contributed by diatoms. Much larger algae, commonly known as seaweeds, are important locally; "Sargassum" forms floating drifts, while kelp form seabed forests. Flowering plants in the form of seagrasses grow in "meadows" in sandy shallows, mangroves line the coast in tropical and subtropical regions and salt-tolerant plants thrive in regularly inundated salt marshes. All of these habitats are able to sequester large quantities of carbon and support a biodiverse range of larger and smaller animal life.
Edible seaweed
In some parts of Asia, nori 海苔 (in Japan), zicai 紫菜 (in China), and gim 김 (in Korea), sheets of the dried red alga "Porphyra" are used in soups or to wrap sushi or onigiri. "Chondrus crispus" (commonly known as Irish moss) is another red alga used in producing various food additives, along with Kappaphycus and various gigartinoid seaweeds.
Novaculichthys taeniourus
Juveniles resemble algae and mimic the movements of detached, drifting seaweed by swaying back and forth in the currents.
Endocladia muricata
"E. muricata" is common north of Point Conception, and is one of the most common algae in the high intertidal zone of the central California, coast. It commonly forms the top-most conspicuous band of seaweed along that coast. "E. muricata" often grows with "Pelvetiopsis limitata" (dwarf rockweed) and "Mastocarpus papillatus" (Turkish washcloth), on rocks in the high intertidal.
"E. muricata"'s thallus is 4–8 cm tall, short & bushy; branches cylindrical with sub-dichotomous branching; covered with minute, soft conical spines; blackish-brown to dark red to yellow. Dries to almost black. It is usually not slippery to walk on, dry or wet.
Wakame
, "Undaria pinnatifida", is a species of edible seaweed, a type of marine algae, and a sea vegetable. It has a subtly sweet, but distinctive and strong flavour and texture. It is most often served in soups and salads.
Seaweed cultivator
Seaweed cultivators (the devices) are just now becoming available to the public, mainly because of the LED (light-emitting diode) which has made low-cost, reliable, and waterproof illumination sources (especially in the red 660-nanometer spectrum) feasible. Seaweed cultivators are an offshoot of algae scrubbers, which were developed to filter aquariums. By replacing the aquarium with a reservoir of fertilized seawater, a stand-alone cultivator becomes possible, and even a desktop cultivator is possible if the size is small enough or if the reservoir is placed beneath the desk.
Salmon
Yet another attractive alternative is the increased use of seaweed. Seaweed provides essential minerals and vitamins for growing organisms. It offers the advantage of providing natural amounts of dietary fiber and having a lower glycemic load than grain-based fish meal. In the best-case scenario, widespread use of seaweed could yield a future in aquaculture that eliminates the need for land, freshwater, or fertilizer to raise fish.
Algaculture
The majority of algae that are intentionally cultivated fall into the category of microalgae (also referred to as phytoplankton, microphytes, or planktonic algae). Macroalgae, commonly known as seaweed, also have many commercial and industrial uses, but due to their size and the specific requirements of the environment in which they need to grow, they do not lend themselves as readily to cultivation (this may change, however, with the advent of newer seaweed cultivators, which are basically algae scrubbers using upflowing air bubbles in small containers).
Harmful algal bloom
The other types of algae are diatoms and dinoflagellates, found primarily in marine environments, such as ocean coastlines or bays, where they can also form algal blooms, commonly called red tides. Red tides, however, may be a natural phenomenon, although when they form close to coastlines or in estuaries. They can occur when warmer water, salinity, and nutrients reach certain levels, which then stimulates their growth. Most red tide algae are dinoflagellates. They are visible in water at a concentration of 1,000 algae cells per milliliter, while in dense blooms they can measure over 200,000 per milliliter.
Notomithrax ursus
There is also evidence that the species of algae that the seaweed crab attaches to its body are preferred species for consumption as well, so the masking behavior of these crabs serves as food storage. The crab can eat up to 4.1% of the algae masking them when there is no food available to consume. The types of algae for masking may also be chosen based on “calorific value or content of vitamins, nitrogen, or specific nutrients such as sugars and amino acids”.
Ulva intestinalis
Ulva intestinalis, formerly referred to as "Enteromorpha intestinalis" (Linnaeus) Nees, is a green alga in the family Ulvaceae, of the genus "Ulva" (sea lettuce), also known by the common names gutweed and grass kelp. Until they were reclassified by genetic work completed in the early 2000s, the tubular members of the genus "Ulva" were in the genus "Enteromorpha".
Suaeda maritima
Suaeda maritima is a species of flowering plant in the amaranth family known by the common names herbaceous seepweed and annual seablite. It is a yellow-green shrub with fleshy, succulent leaves and green flowers. It grows to about 35 cm in salt marshes.
Seaweed blenny
The seaweed blenny is a diurnal species and feeds mostly on algae. The diet also includes such invertebrates as polychaete worms, crustaceans and hydroids, which it picks off the substrate with its beak-like mouth. A male may have several females in his territory, all of which deposit their eggs in a shared nest. This is in a crevice in a rock, inside a sponge, in a mollusc shell or in a can or other piece of discarded human debris. The male guards the nest until the eggs hatch. The larvae are planktonic at first, settling on the seabed when about long.
Tripleurospermum maritimum
Tripleurospermum maritimum (syn. "Matricaria maritima") is a species of flowering plant in the aster family commonly known as false mayweed or sea mayweed. It is found in many coastal areas of Northern Europe, including Scandinavia and Iceland, often growing in sand or amongst beach pebbles.
Himanthalia elongata
Himanthalia elongata is a brown alga (class Phaeophyta or Phaeophyceae) in the order Fucales, also known by the common names thongweed, sea thong and sea spaghetti. It is found in the north east Atlantic Ocean and the North Sea.
Stylonema alsidii
It is one of the algae of the Houtman Abrolhos, found off the coast of Western Australia. It is one of the red seaweeds of South Africa, including the seaweeds of the Cape Peninsula and False Bay.
Caulerpa taxifolia
It is thought that the seaweed was accidentally released into coastal waters of the Mediterranean Sea (just below Jacques Cousteau's) Oceanographic Museum of Monaco in 1984. Ten years later, the claim was made that "Caulerpa" had grown to cover , and was preventing native plants from growing. This concern earned the algae the dubious nickname "Killer Algae" after the title of a book written on the subject. Its author, Marine biologist Alexandre Meinesz first discovered the alga in the 1980s, and requested the help of the Monaco Oceanographic Museum, which sat right next to the first known "C. taxifolia" patch. The director of the museum argued that this invasion probably happened naturally, the result of ocean currents carrying a tropical species into the area. The parties bickered publicly for years over whether the species was natural or invasive, and whether the museum had released it or not, at the expense of sound scientific research on the species and its ecological significance.
Phyllospora comosa
Phyllospora comosa, known as crayweed, is a species of brown algae in the Seirococcaceae family. It is found in the oceans around Australia and New Zealand.
Spongites yendoi
On the rocky coasts of South Africa, "Spongites yendoi" is the main algal component of a community of organisms commonly found in the low intertidal zone. A thin layer of this alga tends to cover rock surfaces and seaweeds grow as epiphytes on top. Both the coralline alga and the seaweeds are grazed by the pear limpet and other herbivores. Twice a year, "Spongites yendoi" sloughs off its upper layers but nevertheless seaweeds soon grow again on the exposed surface which is usually kept clean by the feeding activities of the herbivores. Sloughing is probably a means of eliminating old reproductive structures and damaged surface cells, and reducing the risk of surface penetration by burrowing organisms.
Desmarestia herbacea
Desmarestia herbacea is a species of brown algae found worldwide. Its common names include color changer, Desmarest's flattened weed, and sea sorrel, though the last name can also refer to other species of "Desmarestia".
Algae
Algae are prominent in bodies of water, common in terrestrial environments, and are found in unusual environments, such as on snow and ice. Seaweeds grow mostly in shallow marine waters, under deep; however, some such as Navicula pennata have been recorded to a depth of .
Seaweed
Two specific environmental requirements dominate seaweed ecology. These are the presence of seawater (or at least brackish water) and the presence of light sufficient to drive photosynthesis. Another common requirement is a firm attachment point, although some genera such as "Sargassum" and "Gracilaria" have species that float freely. As a result, seaweed most commonly inhabit the part of a sea that is close to the shore (the littoral zone) and within that zone more frequently on rocky shores than on sand or shingle. Seaweed occupy a wide range of ecological niches. The highest elevation is only wetted by the tops of sea spray, the lowest is several meters deep. In some areas, littoral seaweed can extend several miles out to sea. The limiting factor in such cases is sunlight availability. The deepest living seaweed are some species of red algae.
Water garden
Algae are found in almost all ponds. There are hundreds of species of algae that can grow in garden ponds, but they are usually noticed only when they become abundant. Algae often grow in very high densities in ponds because of the high nutrient levels that are typical of garden ponds. Generally, algae attaches itself to the sides of the pond and remains innocuous. Some species of algae, such as "blanket weed", can grow up to a foot a day under ideal conditions and can rapidly clog a garden pond. On the other hand, free floating algae are microscopic and are what cause pond water to appear green. Blanket weed, although unsightly, is actually a sign that the water is clean and well-balanced. Green water (free floating algae) means there are too many nutrients in the water, usually from rotting vegetation or too many fish for the space. Killing the free floating algae with chemicals will often cause it to die, rot, and then make the problem even worse as more nutrients enter the water. Adding more floating or submerged (unpotted) plants can help with the green water, as they can take the nutrients out of the water. There are also filters that can be installed to remove the nutrients and all types of algae from the water. Many ponds naturally go green early in the spring and then clear up.
Introduced species
A very troublesome marine species in southern Europe is the seaweed "Caulerpa taxifolia". "Caulerpa" was first observed in the Mediterranean Sea in 1984, off the coast of Monaco. By 1997, it had covered some 50 km². It has a strong potential to overgrow natural biotopes, and represents a major risk for sublittoral ecosystems. The origin of the alga in the Mediterranean was thought to be either as a migration through the Suez Canal from the Red Sea, or as an accidental introduction from an aquarium. Another troublesome plant species is the terrestrial plant "Phyla canescens," which was intentionally introduced into many countries in North America, Europe, and Africa as an ornamental plant. This species has become invasive in Australia, where it threatens native rare plants and causes erosion and soil slumping around river banks. It has also become invasive in France where it has been listed as an invasive plant species of concern in the Mediterranean region, where it can form monocultures that threaten critical conservation habitats.
Caulerpa sedoides
The light to medium green delicate alga or seaweed with a [thallus]] that grows to a size of around . It has small elongated ovoid shaped beads arranged loosely along the main stolon or axis. The stolon is often branched and arises from rhizomes or running stolons) that are usually fixed to rocky surfaces in a marine environment.
Seaweed farming
Seaweed farming helps to preserve coral reefs, by increasing diversity where the algae and seaweed have been introduced and it also provides added niche for local species of fish and invertebrates. Farming may be beneficial by increasing the production of herbivorous fishes and shellfish in the area. reported an increase in Siginid population after the start of extensive farming of eucheuma seaweed in villages in North Sulawesi, Indonesia.
Monostroma
Monostroma is a genus of marine green algae (seaweed) in the family Monostromataceae. As the name suggests, algae of this genus are monostromatic (single cell layered). "Monostroma kuroshiense", an algae of this genus, is commercially cultivated in East Asia and South America for the edible product "hitoegusa-nori" or "hirohano-hitoegusa nori", popular sushi wraps. "Monostroma" oligosaccharides with degree of polymerization 6 prepared by agarase digestion from "Monostroma nitidum" polysaccharides have been shown to be an effective prophylactic agent during "in vitro" and "in vivo" tests against Japanese encephalitis viral infection. The sulfated oligosaccharides from "Monostroma" seem to be promising candidates for further development as antiviral agents. The genus "Monostroma" is the most widely cultivated genus among green seaweeds.
Sea foam
The composition of sea foam is generally a mixture of decomposed organic materials, including zooplankton, phytoplankton, algae (including diatoms), bacteria, fungi, protozoans, and vascular plant detritus, though each occurrence of sea foam varies in its specific contents. In some areas, sea foam is found to be made up of primarily protein, dominant in both fresh and old foam, as well as lipids and carbohydrates. The high protein and low carbohydrate concentration suggest that sugars originally present in the surrounding mucilage created by algae or plant matter has been quickly consumed by bacteria. Additional research has shown that a small fraction of the dry weight in sea foam is organic carbon, which contains phenolics, sugars, amino sugars, and amino acids. In the Bay of Fundy, high mortality rates of an abundant tube-dwelling amphipod ("Corophium volutator)" by natural die-offs as well as predation by migrating seabirds contributed to amino sugars released in the surrounding environment and thus, in sea foam.
Marine microorganism
Algae can grow as single cells, or in long chains of cells. Green algae are a large group of photosynthetic eukaryotes that include many microscopic organisms. Green algae include unicellular and colonial flagellates as well as various colonial, coccoid, and filamentous forms. There are about 6000 species.
Palmariales
Palmariales is an order of marine algae. It includes the edible seaweed dulse ("Palmaria palmata").
Saccorhiza polyschides
Saccorhiza polyschides, common name Furbellow, is a large brown algae of the lower shore and is the largest seaweed found in Europe.
Ocean storage of carbon dioxide
In order to mitigate global warming, seaweed farming is both a possible and plausible way. This method was adopted in early ocean algae proposals to mitigate global warming. This is done through commercial kelp farms designed to take up tens of thousands of square kilometres of the open ocean. Through this method, seaweed beds will perform as an effective sinks by decreasing the level of dissolved inorganic carbon (DIC) in the ocean.
Seaweeds do the above by removing carbon through the process of photosynthesis, taking in excess CO2 and producing O2. Facts and figures have shown that 0.7 million tonnes of carbon are removed from the sea each year by commercially harvested seaweeds. Even though seaweed biomass is small as compared to the coastal region. They remain essential due to their biotic components, the ability to provide valuable ecosystem services and high primary productivity. Seaweeds are different from mangroves and seagrasses, they are photosynthetic algal organisms and non-flowering. Even so, they are primary producers that grows in the same way as their terrestrial counterparts, both of which assimilate carbon by the process of photosynthesis and generates new biomass by taking up phosphorus, nitrogen, and other minerals.
Sushi
The black seaweed wrappers used in "makimono" are called "nori" (海苔). "Nori" is a type of algae, traditionally cultivated in the harbors of Japan. Originally, algae was scraped from dock pilings, rolled out into thin, edible sheets, and dried in the sun, in a process similar to making rice paper. Today, the commercial product is farmed, processed, toasted, packaged, and sold in sheets.
Codium fragile
Codium fragile, known commonly as green sea fingers, dead man's fingers, felty fingers, forked felt-alga, stag seaweed, sponge seaweed, green sponge, green fleece, and oyster thief, is a species of seaweed in the family Codiaceae. It originates in the Pacific Ocean near Japan and has become an invasive species on the coasts of the Northern Atlantic Ocean.
Ascoseira
Ascoseira is a monotypic genus of seaweed in the brown algae (class Phaeophyceae). The single and type species, Ascoseira mirabilis Skottsberg, is a large parenchymatous macroalgae, and is endemic to the Antarctic Ocean. "Ascoseira" is assigned to its own order. The alga grows in subtidal waters at depths of from 3 to 15 meters.
Marine biology
Algal life is widespread and very diverse under the ocean. Microscopic photosynthetic algae contribute a larger proportion of the world's photosynthetic output than all the terrestrial forests combined. Most of the niche occupied by sub plants on land is actually occupied by macroscopic algae in the ocean, such as "Sargassum" and kelp, which are commonly known as seaweeds that create kelp forests.
Shewanella algae
Shewanella algae is a rod-shaped Gram-negative marine bacterium.
Algae
Naturally growing seaweeds are an important source of food, especially in Asia. They provide many vitamins including: A, B, B, B, niacin, and C, and are rich in iodine, potassium, iron, magnesium, and calcium. In addition, commercially cultivated microalgae, including both algae and cyanobacteria, are marketed as nutritional supplements, such as spirulina, "Chlorella" and the vitamin-C supplement from "Dunaliella", high in beta-carotene.
Wrack (seaweed)
Wrack is part of the common names of several species of seaweed in the family Fucaceae. It may also refer more generally to any seaweeds or seagrasses that wash up on beaches and may accumulate in the wrack zone.
Algae
No definition of algae is generally accepted. One definition is that algae "have chlorophyll as their primary photosynthetic pigment and lack a sterile covering of cells around their reproductive cells". Although cyanobacteria are often referred to as "blue-green algae", most authorities exclude all prokaryotes from the definition of algae.
List of seaweeds and marine flowering plants of Australia (temperate waters)
The list of seaweeds and marine flowering plants of Australia (temperate waters) is a list of marine species that form a part of the flora of Australia.
Nori
Raw seaweed is 85% water, 6% protein, 5% carbohydrates, and has negligible fat (table). In a 100 gram reference amount, seaweed is a rich source (20% or more of the Daily Value, DV) of vitamin A, vitamin C, riboflavin, and folate (table). Seaweed is a moderate source (less than 20% DV) of niacin, iron, and zinc. Seaweed has a high content of iodine, providing a substantial amount in just one gram. A 2014 study reported that dried purple laver ("nori") contains vitamin B12 in sufficient quantities to meet the RDA requirement (Vitamin B12 content: 77.6 μg /100 g dry weight).
Palmariaceae
Palmariaceae is a family of algae. It includes the edible seaweed dulse ("Palmaria palmata").
Gelidium amansii
Gelidium amansii, also known as umutgasari, is an economically important species of red algae commonly found and harvested in the shallow coast (3 to 10 m or 10 to 33 ft of depth below the water) of many East Asian countries including North and South Korea, China, Japan, Singapore, and northeast Taiwan. "G. amansii" is an important food source in East Asian countries and has been shown to have medicinal effects on dieting. Hence, in folklore medicine "G. amansii" is used to treat constipation. This algae is used to make agar, whose components are the polysaccharide agarose and agaropectin, from the large amount of algin which is located in the algae's cell wall, as well it is sometimes served as part of a salad, puddings, jams, and other culinary dishes in producing regions. Agar is a gelatinous substance that is commercially used as an incubation matrix for microbes and other products that require an ecologically friendly gelatinous matrix. "G. amansii" can be purple, red, to yellowish-red because it contains the class of pigments known as phycobiliprotein. Its branching body is cartilaginous and can grow up to a height of 8 to 30 cm or 3 to 12 in. "G. amansii" may have four or five opposite, compound-lobed, pinnate leaves on each branch. It is uniaxial with an apical cell and whorled cells coming from the axial towards the exterior of the algae. The pith is compacted with apical cells and the epidermis is formed by rounded whorled cells. "G. amansii" is being studied as a cheap biofuel.
Suaeda
Suaeda is a genus of plants also known as seepweeds and sea-blites. Most species are confined to saline or alkaline soil habitats, such as coastal salt-flats and tidal wetlands. Many species have thick, succulent leaves, a characteristic seen in various plant genera that thrive in salty habitats (halophile plants).
Herbivore
Herbivorous fish and marine animals are an indispensable part of the coral reef ecosystem. Since algae and seaweeds grow much faster than corals they can occupy spaces where corals could have settled. They can outgrow and thus outcompete corals on bare surfaces. In the absence of plant-eating fish, seaweeds deprive corals of sunlight. They can also physically damage corals with scrapes.
Menai Bay Conservation Area
The historical practices in the area consisted of cultivation of "Eucheuma" seaweed and use of "Ulva" and "Enteromorpha" species as fish baits; green algae was also collected for medicinal use. USAID supported pilot projects in three islands where seaweed grew densely, given the protection provided at these locations from waves. The subspecies of "Eucheuma", namely "Eucheuma spinosum" and "Eucheuma striatum", were selected for the purpose by adopting fixed bottom cultivation method. They were also developed as demonstration farms to provide training and extension services to the local fishermen in enhancing the quality of dry seaweed. Though "Eucheuma spinosum" was grown largely in the area, "Eucheuma cottonii" was also considered but proved to be not profitable due to climatic effects. Commercial collection of seaweed were also started by private companies, which contributed nearly 20% to the island's earning and employed a significant fraction of women. The local women have engaged in seaweed farming and coconut-husk weaving. However, a "monopsonyl arrangement" of farming controlled by individual buyers to buy the yield at their predetermined rates, on the basis of the initial supply of materials such as lines and seaweed seedlings to the producers, is in vogue.
Seaweed fertiliser
Several of the 12,000+ varieties of seaweed in the ocean have been shown to be valuable additions to the organic garden and can be abundantly available free for those living near the coast. However, caution should be observed when collecting seaweed, particularly from areas that are liable to pollution, such as downriver (including estuaries) of industrial activities as seaweed is susceptible to contamination. There are also legal implications relating to gathering seaweed, and concerns about sustainability. In terms of soil structure, seaweed does not add a great deal of bulk, but its jelly like alginate content helps to bind soil crumbs together, and it contains all soil nutrients (0.3% N, 0.1% P, 1.0% K, plus a full range of trace elements) and amino acids. For those who cannot gather fresh seaweed, it is available commercially in a dried 'meal' form or as a concentrated liquid extract which is active in significantly smaller rates. While 'meal' products are limited to soil applications due to their insolubility, foliar feeding or root zone applications through drip lines are possible with soluble extracts.
Sepharose
Sepharose is a tradename for a crosslinked, beaded-form of agarose, a polysaccharide polymer material extracted from seaweed. Its brand name is derived from Separation-Pharmacia-Agarose. A common application for the material is in chromatographic separations of biomolecules.
Endocladia muricata
Endocladia muricata, commonly known as nailbrush seaweed or turfweed, is a marine alga that is widely distributed along the shores of the North Pacific Ocean, from Alaska to Punto Santo Tomas, Baja California.
Caulerpa taxifolia
Caulerpa taxifolia is a species of seaweed, an alga of the genus "Caulerpa" native to the Indian Ocean. It is widely used ornamentally in aquariums, because it is considered attractive and neat in arrangement, and is easy to establish and care for. The alga has a stem (rhizome) which spreads horizontally just above the seafloor. From this stem grow vertical fern-like pinnae, whose blades are flat like those of the yew ("Taxus"), hence the species name "taxifolia".
Malaysian cuisine
Edible seaweed is a traditional food for certain seaside communities throughout Sabah and also possess GI status. Latok is similar in appearance to clusters of green-hued fish eggs or grapes, and is typically prepared as a salad by the Bajau people. Coral seaweed is another popular seaplant product; in recent times it is marketed as a gourmet health food to both locals and tourists, and is given the moniker of "sea bird's nest" (Chinese : 海底燕窝) as coral seaweed acquires a similar gelatinous texture when dissolved in water.
Seaweed collecting
Anna Atkins, thought to be the first female photographer, published the first book using photographs as illustrations. This was "Photographs of British Algae: Cyanotype Impressions" and contained pictures of seaweed.
Lamina (algae)
The lamina or blade in macroscopic algae like seaweed is a generally flattened structure that typically forms the principal bulk of the thallus. It is often developed into specialised organs such as flotation bladders and reproductive organs.
Seaweed cultivator
The type of seaweed that can be grown in a seaweed cultivator is currently limited to green types, mostly Angel Hair and sea lettuce, because other types such as Nori require more complex control of the water temperature and other variables. Angel Hair and sea lettuce, however, can be grown at home at room temperature.
Caulerpa brachypus
In Florida, this seaweed has been dubbed the "killer algae". First recorded in the state in 1999, by 2003 it had shown explosive growth and spread widely, with some near shore reefs in Palm Beach County becoming so overwhelmed that fish and lobsters were no longer present. During hurricanes in 2004, it was scoured from the rocky reefs and disappeared, but over the next few years, it became re-established, once more forming dense stands. It is thought to become so abundant on Florida's coast because of the sewage outflows which result in extra nutrients being present in the water. Such extensive algal cover is likely to kill corals, sponges and other sessile invertebrates, and force more mobile organisms to move elsewhere.
Wrack (seaweed)
It consists largely of species of "Fucus" — brown seaweeds with flat branched ribbon-like fronds, characterized in "F. serratus" by a saw-toothed margin and in "F. vesiculosus", another common species, by bearing air-bladders. Another component of sea wrack may be seagrasses such as "Zostera marina" a marine flowering plant with bright green long narrow grass-like leaves. "Posidonia australis", which occurs sub-tidally on the southern coasts of Australia, sheds its older ribbon-like leaf blades in winter, resulting in thick accumulations along more sheltered shorelines.Historically wrack was used for making manure, and for making "kelp", a form of potash.
Sea6 Energy
Traditionally, algal-based biofuels have been derived from microalgae that grow in fresh water sources. Shrikumar Suryanarayan and the 4 co-founders sought to research the viability of macroalgae (seaweed) as a fuel source. To do this, they needed a way to efficiently farm the seaweed, which led to the creation of a farming system built from a marine plastics polymer. Sea6 Energy successfully applied for a patent for their aquatic farming structure in 2012 (one of their two patents that has been published).
Aquaculture
Microalgae, also referred to as phytoplankton, microphytes, or planktonic algae, constitute the majority of cultivated algae. Macroalgae commonly known as seaweed also have many commercial and industrial uses, but due to their size and specific requirements, they are not easily cultivated on a large scale and are most often taken in the wild.
Wildlife of Antarctica
Other algae live in or on the sea ice, often on its underside, or on the seabed in shallow areas. Over 700 seaweed species have been identified, of which 35% are endemic. Outside of the ocean many algae are found in freshwater both on the continent and on the subantarctic islands. Terrestrial algae, such as snow algae, have been found living in soil as far south as 86° 29'. Most are single-celled. In summer algal blooms can cause snow and ice to appear red, green, orange, or grey. These blooms can reach about 10 cells per mL. The dominant group of snow algae is chlamydomonas , a type of green algae.