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Aquaculture (less commonly spelled aquiculture [1]), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. lotus).
Subsets of it include (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 plankton and seaweed, shellfish like shrimp or oysters, and marine finfish, in saltwater ponds
Fish farming or pisciculture involves commercial breeding of fish, most often for food, in fish tanks or artificial enclosures such as fish ponds. It is a particular type of aquaculture , which is the controlled cultivation and harvesting of aquatic animals such as fish, crustaceans , molluscs and so on, in natural or pseudo-natural environments.
The pond and cage cultures used are based only on the fish. They don't take advantage of the productivity increases that could take place if other trophic levels were included. Expensive artificial feeds are used, partly to supply the fish with protein.
The Hawaiian fishpond was primarily a grazing area in which the fishpond-keeper cultivated algae; much in the way cattle ranchers cultivate grass for their cattle. [3] The porous lava walls let in seawater (or sometimes fresh or brackish water, as in the case of the "Menehune" fishpond near Līhuʻe, Kauaʻi), but prevent the fish from escaping.
Vegetative propagation is usually considered a cloning method. [8] However, root cuttings of thornless blackberries (Rubus fruticosus) will revert to thorny type because the adventitious shoot develops from a cell that is genetically thorny. Thornless blackberry is a chimera, with the epidermal layers genetically thornless but the tissue ...
Propagation is by cuttings. [16] It is an invasive species in Europe, Asia, Africa, and Oceania. It was introduced into County Down, Ireland in about 1836, and appeared in Great Britain in 1841, spreading through both countries in ponds, ditches and streams, which were often choked with its rank growth. [17] [14] [15] [18]
Aquaponics is a food production system that couples aquaculture (raising aquatic animals such as fish, crayfish, snails or prawns in tanks) with hydroponics (cultivating plants in water) whereby the nutrient-rich aquaculture water is fed to hydroponically grown plants.