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Brakish Water
Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root '' brak''. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment (see article on shrimp farms). Technically, brackish water contains between 0.5 and 30 grams of salt per litre—more often expressed as 0.5 to 30 parts per thousand (‰), which is a specific grav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salinity
Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to ‰). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water. A contour line of constant salinity is called an ''isohaline'', or sometimes ''isohale''. Definitions Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monodactylus Argenteus
''Monodactylus argenteus'' is a species of fish in the family Monodactylidae, the moonyfishes. Its common names include silver moonyfish, or silver moony,Froese, R. and D. Pauly, Editors''Monodactylus argenteus''.FishBase. 2017. butter bream, and diamondfish.''Monodactylus argenteus''. Fishes of Australia. It is native to the western Pacific and s, including the , , and associated estuaries, such as the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flounder
Flounders are a group of flatfish species. They are demersal fish, found at the bottom of oceans around the world; some species will also enter estuaries. Taxonomy The name "flounder" is used for several only distantly related species, though all are in the suborder Pleuronectoidei (families Achiropsettidae, Bothidae, Pleuronectidae, Paralichthyidae, and Samaridae). Some of the better known species that are important in fisheries are: * Western Atlantic ** Gulf flounder – ''Paralichthys albigutta'' ** Southern flounder – ''Paralichthys lethostigma'' ** Summer flounder (also known as ''fluke'') – ''Paralichthys dentatus'' ** Winter flounder – ''Pseudopleuronectes americanus'' * European waters **European flounder – ''Platichthys flesus'' ** Witch flounder – ''Glyptocephalus cynoglossus'' * North Pacific ** Halibut – ''Hippoglossus stenolepis'' ** Olive flounder – ''Paralichthys olivaceus'' Eye migration Larval flounder are born with one eye on each side o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euryhaline
Euryhaline organisms are able to adapt to a wide range of salinities. An example of a euryhaline fish is the molly (''Poecilia sphenops'') which can live in fresh water, brackish water, or salt water. The green crab (''Carcinus maenas'') is an example of a euryhaline invertebrate that can live in salt and brackish water. Euryhaline organisms are commonly found in habitats such as estuaries and tide pools where the salinity changes regularly. However, some organisms are euryhaline because their life cycle involves migration between freshwater and marine environments, as is the case with salmon and eels. The opposite of euryhaline organisms are stenohaline ones, which can only survive within a narrow range of salinities. Most freshwater organisms are stenohaline, and will die in seawater, and similarly most marine organisms are stenohaline, and cannot live in fresh water. Osmoregulation Osmoregulation is the active process by which an organism maintains its level of water cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravesend, Kent
Gravesend is a town in northwest Kent, England, situated 21 miles (35 km) east-southeast of Charing Cross (central London) on the south bank of the River Thames and opposite Tilbury in Essex. Located in the diocese of Rochester, it is the administrative centre of the Borough of Gravesham. Its geographical situation has given Gravesend strategic importance throughout the maritime and communications history of South East England. A Thames Gateway commuter town, it retains strong links with the River Thames, not least through the Port of London Authority Pilot Station and has witnessed rejuvenation since the advent of High Speed 1 rail services via Gravesend railway station. The station was recently refurbished and now has a new bridge. Toponymy Recorded as Gravesham in the Domesday Book of 1086 when it belonged to Odo, Earl of Kent and Bishop of Bayeux, the half-brother of William the Conqueror, its name probably derives from ''graaf-ham'': the home of the reeve or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thames Estuary
The Thames Estuary is where the River Thames meets the waters of the North Sea, in the south-east of Great Britain. Limits An estuary can be defined according to different criteria (e.g. tidal, geographical, navigational or in terms of salinity). For this reason the limits of the Thames Estuary have been defined differently at different times and for different purposes. Western This limit of the estuary has been defined in two main ways: * The narrow estuary is strongly tidal and is known as the Tideway. It starts in south-west London at Teddington Lock and weir, Teddington/Ham. This point is also mid-way between Richmond Lock which only keeps back a few miles of man-made head (stasis) of water during low tide and the extreme modern-era head at Thames Ditton Island on Kingston reach where slack water occurs at maximal high tide in times of rainfall-caused flooded banks. In terms of salinity the transition from freshwater to estuarine occurs around Battersea; east of the Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pike (fish)
''Esox'' is a genus of freshwater fish commonly known as pike or pickerel. It is the type genus of the family Esocidae. The type species of the genus is ''Esox lucius'', the northern pike. ''Esox'' has been present in Laurentia (which later became North America) and Eurasia since the Paleocene. Modern large pike species are native to the Palearctic and Nearctic realms, ranging across Northern America and from Western Europe to Siberia in North Asia. Pikes have the elongated, torpedo-like shape typical of predatory fishes, with sharply pointed heads and sharp teeth. Their coloration is typically grey-green with a mottled or spotted appearance with stripes along their backs, providing camouflage among underwater weeds, and each individual pike marking patterns are unique like fingerprints. Pikes can grow to a maximum recorded length of , reaching a maximum recorded weight of . Etymology The generic name ''Esox'' (pike fish) derives from the Greek ἴσοξ (''ee-soks'', a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perch
Perch is a common name for fish of the genus ''Perca'', freshwater gamefish belonging to the family Percidae. The perch, of which three species occur in different geographical areas, lend their name to a large order of vertebrates: the Perciformes, from the el, πέρκη (), simply meaning perch, and the Latin ''forma'' meaning shape. Many species of freshwater gamefish more or less resemble perch, but belong to different genera. In fact, the exclusively saltwater-dwelling red drum is often referred to as a red perch, though by definition perch are freshwater fish. Though many fish are referred to as perch as a common name, to be considered a true perch, the fish must be of the family Percidae. The type species for this genus is the European perch, ''P. fluviatilis''. Species Most authorities recognize three species within the perch genus: * The European perch (''P. fluviatilis'') is primarily found in Europe, but a few can also be found in South Africa, and even as far ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carp
Carp are various species of oily freshwater fish from the family Cyprinidae, a very large group of fish native to Europe and Asia. While carp is consumed in many parts of the world, they are generally considered an invasive species in parts of Africa, Australia and most of the United States. Biology The cypriniformes (family Cyprinidae) are traditionally grouped with the Characiformes, Siluriformes, and Gymnotiformes to create the superorder Ostariophysi, since these groups share some common features. These features include being found predominantly in fresh water and possessing Weberian ossicles, an anatomical structure derived from the first five anterior-most vertebrae, and their corresponding ribs and neural crests. The third anterior-most pair of ribs is in contact with the extension of the labyrinth and the posterior with the swim bladder. The function is poorly understood, but this structure is presumed to take part in the transmission of vibrations from the swim bl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Dace
The common dace (''Leuciscus leuciscus'') is a species of freshwater and brackish water ray-finned fish from the family Cyprinidae which is native to Europe but which has been introduced to other parts of the world. It is a quarry species for coarse anglers. Description The common dace differs from other members in the genus ''Leuciscus'' found in Europe by its inferior mouth, slightly longer upper jaw which has the tip of the upper lip level with the centre line of the eye and the lack of an obvious snout. It has a yellowish iris and a body which is covered in large silvery scales, the lateral line having 49–52 scales. The anal fin has a concave margin and the caudal fin is forked. The dorsal fin has 2–3 spines and 7–9 soft rays while the anal fin has 3 spines and 8–9 soft rays. The maximum size attained is a total length of . Distribution The common dace is native to Europe and northern Asia where its occurs in the basins of the North Sea, Baltic Sea, White Sea and Bar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rutilus
''Rutilus'' is a genus of fish in the family Cyprinidae found in Eurasia. This genus is a widely distributed lineage of cyprinids and ranges from West Europe to East Siberia. Species In FishBase (2022), nine species are included in the genus: * ''Rutilus caspicus'' (Yakovlev, 1870) (Caspian roach) * ''Rutilus frisii'' ( Nordmann, 1840) (Black sea roach) * ''Rutilus heckelii'' (Nordmann, 1840) * ''Rutilus kutum'' (S. N. Kamensky, 1901) (Caspian kutum) * ''Rutilus meidingeri'' ( Heckel, 1851) * ''Rutilus pigus'' ( Lacépède, 1803) (Pigo) * '' Rutilus rutilus'' (Linnaeus, 1758) (Common roach) * ''Rutilus stoumboudae Bianco & Ketmaier, 2014 * ''Rutilus virgo'' ( Heckel, 1852) (Cactus roach) In a phylogeographic study, Levin et al. (2017) argue that the Ponto-Caspian taxa including ''R. caspicus'', ''R. heckelii'' and ''R. stoumboudae'' could represent a single widespread species whose range extends to Siberia, to be named ''Rutilus lacustris'', whereas ''R. kutum'' is included in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battersea
Battersea is a large district in south London, part of the London Borough of Wandsworth, England. It is centred southwest of Charing Cross and extends along the south bank of the River Thames. It includes the Battersea Park. History Battersea is mentioned in the few surviving Anglo-Saxon geographical accounts as ''Badrices īeg'' meaning "Badric's Island" and later "Patrisey". As with many former parishes beside tidal flood plains the lowest land was reclaimed for agriculture by draining marshland and building culverts for streams. Alongside this was the Heathwall tide mill in the north-east with a very long mill pond regularly draining and filling to the south. The settlement appears in the Domesday Book of 1086 as ''Patricesy'', a vast manor held by St Peter's Abbey, Westminster. Its ''Domesday'' Assets were: 18 hides and 17 ploughlands of cultivated land; 7 mills worth £42 9s 8d per year, of meadow, woodland worth 50 hogs. It rendered (in total): £75 9s 8d. The p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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