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Aquaculture Of Sea Cucumber
Sea cucumber stocks have been overexploited in the wild, resulting in incentives to grow them by aquaculture. Aquaculture means the sea cucumbers are farmed in contained areas where they can be cultured in a controlled manner. In China, sea cucumbers are cultured, along with prawns and some fish species, in integrated multi-trophic systems. In these systems, the sea cucumbers feed on the waste and feces from the other species. In this manner, what would otherwise be polluting byproducts from the culture of the other species become a valuable resource that is turned into a marketable product. __TOC__ History The Chinese and Japanese were the first to develop successful hatchery technology for ''Apostichopus japonicus'', prized for its high meat content and success in commercial hatcheries.James, B. D. (2004)Captive breeding of the sea cucumber, ''Holothuria scabra'', from India In Lovatelli, A. (comp./ed.); Conand, C.; Purcell, S.; Uthicke, S.; Hamel, J.-F.; Mercier, A. (eds.) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microalgae
Microalgae or microphytes are microscopic algae invisible to the naked eye. They are phytoplankton typically found in freshwater and marine systems, living in both the water column and sediment. They are unicellular species which exist individually, or in chains or groups. Depending on the species, their sizes can range from a few micrometers (μm) to a few hundred micrometers. Unlike higher plants, microalgae do not have roots, stems, or leaves. They are specially adapted to an environment dominated by viscous forces. Microalgae, capable of performing photosynthesis, are important for life on earth; they produce approximately half of the atmospheric oxygen and use the greenhouse gas carbon dioxide to grow photoautotrophically. "Marine photosynthesis is dominated by microalgae, which together with cyanobacteria, are collectively called phytoplankton." Microalgae, together with bacteria, form the base of the food web and provide energy for all the trophic levels above them. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thelenota Ananas
''Thelenota ananas'', also known as pineapple sea cucumber, oloturia ananas, tripang, prickly skin cucumber, pointed teat sea cucumber, armoured sea cucumber, giant sea cucumber, sand fish or prickly redfish, is a species of sea cucumber found in tropical Indo-Pacific waters from the Red Sea and East Africa to Hawaii and Polynesia. Description ''Thelenota ananas'' (pineapple sea cucumber) is a species of sea cucumber characterized by its large size, warm colors, and pointed, star-shaped teats covering the entire body, grouped in rows of 2 or 3, as seen in Figure 1. Their body is reddish-orange in color, with the teats slightly darker. They are able to reach up to 70 centimeters (28 in) in length, with a weight of between 3 kg to 6 kg, and have numerous large tube feet on the flat ventral side of their body. ''T. ananas'' is a slow growing organism. Environment The environment of ''T. ananas'' is found in clean, sandy bottoms of lagoons with a depth of up to 30 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mariculture
Mariculture or marine farming is a specialized branch of aquaculture (which includes freshwater aquaculture) involving the cultivation of marine organisms for food and other animal products, in enclosed sections of the open ocean ( offshore mariculture), fish farms built on littoral waters ( inshore mariculture), or in artificial tanks, ponds or raceways which are filled with seawater ( onshore mariculture). An example of the latter is the farming of marine fish, including finfish and shellfish like prawns, or oysters and seaweed in saltwater ponds. Non-food products produced by mariculture include: fish meal, nutrient agar, jewellery (e.g. cultured pearls), and cosmetics. Methods Algae Shellfish Similar to algae cultivation, shellfish can be farmed in multiple ways: on ropes, in bags or cages, or directly on (or within) the intertidal substrate. Shellfish mariculture does not require feed or fertilizer inputs, nor insecticides or antibiotics, making shellfish aquacult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (biology)
In biology, a substrate is the surface on which an organism (such as a plant, fungus, or animal) lives. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock (its substrate) can be itself a substrate for an animal that lives on top of the algae. Inert substrates are used as growing support materials in the hydroponic cultivation of plants. In biology substrates are often activated by the nanoscopic process of substrate presentation. In agriculture and horticulture * Cellulose substrate * Expanded clay aggregate (LECA) * Rock wool * Potting soil * Soil In animal biotechnology Requirements for animal cell and tissue culture Requirements for animal cell and tissue culture are the same as described for plant cell, tissue and organ culture (In Vitro Culture Techniques: The Biotechnological Principles). Desirable requirements are (i) air conditioning of a room, (ii) hot room with temperature recorder, (iii) microscope r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polythene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bottles, etc.). , over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market. Many kinds of polyethylene are known, with most having the chemical formula (C2H4)''n''. PE is usually a mixture of similar polymers of ethylene, with various values of ''n''. It can be ''low-density'' or ''high-density'': low-density polyethylene is extruded using high pressure () and high temperature (), while high-density polyethylene is extruded using low pressure () and low temperature (). Polyethylene is usually thermoplastic, but it can be modified to become thermosetting instead, for example, in cross-linked polyethylene. History Polyethylene was first synthesized by the German chemist Hans v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirulina (genus)
''Spirulina'' is a genus of cyanobacteria. Species * '' Spirulina abbreviata'' * '' Spirulina agilis'' * '' Spirulina agilissima'' * '' Spirulina albida'' * '' Spirulina ardissoni'' * '' Spirulina baltica'' * '' Spirulina bayannurensis'' * '' Spirulina breviarticulata'' * '' Spirulina cabrerae'' * '' Spirulina caldaria'' * '' Spirulina cavanillesiana'' * '' Spirulina condensata'' * '' Spirulina corakiana'' * '' Spirulina flavovirens'' * ''Spirulina funiformis'' * '' Spirulina gessneri'' * '' Spirulina gomontiana'' * '' Spirulina gomontii'' * ''Spirulina gordiana'' * ''Spirulina gracilis'' * ''Spirulina innatans'' * ''Spirulina labyrinthiformis'' * ''Spirulina laxa'' * ''Spirulina laxissima'' * ''Spirulina legitima'' * ''Spirulina magnifica'' * ''Spirulina major'' * ''Spirulina margaritae'' * '' Spirulina mariae'' * '' Spirulina massartii'' * '' Spirulina maxima'' * '' Spirulina miniata'' * '' Spirulina minima'' * '' Spirulina mukdensis'' * '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Navicula
''Navicula'' is a genus of boat-shaped diatom algae, comprising over 1,200 species. ''Navicula'' is Latin for "small ship", and also a term in English for a boat-shaped incense-holder. Diatoms — eukaryotic, primarily aquatic, single-celled photosynthetic organisms — play an important role in global ecology, producing about a quarter of all the oxygen within Earth's biosphere, often serving as foundational organisms, or keystone species in the food chain of many environments where they provide a staple for the diets of many aquatic species. Mobility ''Navicula'' diatoms have been observed to possess a motile ability to glide over one another and on hard surfaces such as microscope slides. Around the outside of the navicula's shell is a girdle of mucilage strands that can flow and thus act as a tank track. File:Navicula tripunctata 2.jpg, ''Navicula tripunctata''type species In zoological nomenclature, a type species (''species typica'') is the species name wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitzchia
''Nitzschia'' is a common pennate marine diatom. In the scientific literature, this genus, named after Christian Ludwig Nitzsch, is sometimes termed ''Nitzchia'', and it has many species described, which all have a similar morphology. Occurrence ''Nitzschia'' is found mostly in colder waters, and is associated with both Arctic and Antarctic polar sea ice, where it is often found to be the dominant diatom. ''Nitzschia'' includes several species of diatoms known to produce the neurotoxin known as domoic acid, a toxin responsible for the human illness called amnesic shellfish poisoning. The species '' N. frigida'' is found to grow exponentially even at temperatures between −4 and −6 °C. Some ''Nitzschia'' species are also extremophiles by dent of tolerance to high salinity; for example, some halophilic species of ''Nitzschia'' are found in the Makgadikgadi Pans in Botswana.C. Michael Hogan (2008The Megalithic Portal, ed. A. Burnham/ref> Species *'' Nitzschia aciculari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diatom
A diatom (Neo-Latin ''diatoma''), "a cutting through, a severance", from el, διάτομος, diátomos, "cut in half, divided equally" from el, διατέμνω, diatémno, "to cut in twain". is any member of a large group comprising several genera of algae, specifically microalgae, found in the oceans, waterways and soils of the world. Living diatoms make up a significant portion of the Earth's biomass: they generate about 20 to 50 percent of the oxygen produced on the planet each year, take in over 6.7 billion metric tons of silicon each year from the waters in which they live, and constitute nearly half of the organic material found in the oceans. The shells of dead diatoms can reach as much as a half-mile (800 m) deep on the ocean floor, and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by transatlantic winds from the African Sahara, much of it from the Bodélé Depression, which was once made up of a system of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benthic
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "the depths." Organisms living in this zone are called benthos and include microorganisms (e.g., bacteria and fungi) as well as larger invertebrates, such as crustaceans and polychaetes. Organisms here generally live in close relationship with the substrate and many are permanently attached to the bottom. The benthic boundary layer, which includes the bottom layer of water and the uppermost layer of sediment directly influenced by the overlying water, is an integral part of the benthic zone, as it greatly influences the biological activity that takes place there. Examples of contact soil layers include sand bottoms, rocky outcrops, coral, and bay mud. Description Oceans The benthic region of the ocean begins at the shore line (intertidal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seagrass
Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the order Alismatales (in the clade of monocotyledons). Seagrasses evolved from terrestrial plants which recolonised the ocean 70 to 100 million years ago. The name ''seagrass'' stems from the many species with long and narrow leaves, which grow by rhizome extension and often spread across large "meadows" resembling grassland; many species superficially resemble terrestrial grasses of the family Poaceae. Like all autotrophic plants, seagrasses photosynthesize, in the submerged photic zone, and most occur in shallow and sheltered coastal waters anchored in sand or mud bottoms. Most species undergo submarine pollination and complete their life cycle underwater. While it was previously believed this pollination was carried out without pollinators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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