|
Baltic Flounder
The Baltic flounder (''Platichthys solemdali'') is a species of flatfish endemic to the Baltic Sea, where it is the only known endemic fish species. It is sympatric with the closely related European flounder (''P. flesus''), which it looks identical to and can only be distinguished from via genetic analysis. However, both have very different spawning behaviors and habitat requirements; the strongly migratory European flounder requires a minimum level of salinity and spawns in the pelagic zone where its eggs are carried by the waves, whereas the largely resident Baltic flounder is more tolerant of salinity decreases and spawns in shallow neritic areas where its eggs sink to the seabed. Due to these different spawning behaviors, both species display a major degree of reproductive isolation, preventing them from intermixing and establishing them as different species. Analyses indicate that the Baltic flounder and the Baltic population of the widespread European flounder both derive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paolo Momigliano
Paolo is both a given name and a surname, the Italian form of the name Paul. Notable people with the name include: People with the given name Paolo Art *Paolo Alboni (1671–1734), Italian painter *Paolo Abbate (1884–1973), Italian-American sculptor *Paolo Antonio Barbieri (1603–1649), Italian painter *Paolo Buggiani (born 1933), Italian contemporary artist *Paolo Carosone (born 1941), Italian painter and sculptor *Paolo Moranda Cavazzola (1486–1522), Italian painter *Paolo Farinati (c. 1524–c. 1606), Italian painter *Paolo Fiammingo (c. 1540–1596), Flemish painter *Paolo Domenico Finoglia (c. 1590–1645), Italian painter *Paolo Grilli (1857–1952), Italian sculptor and painter *Paolo de Matteis (1662–1728), Italian painter *Paolo Monaldi, Italian painter *Paolo Pagani (1655–1716), Italian painter *Paolo Persico (c. 1729–1796), Italian sculptor *Paolo Pino (1534–1565), Italian painter *Paolo Gerolamo Piola (1666–1724), Italian painter *Paolo Porpora (1617– ... [...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] |
Platichthys
''Platichthys'' is a genus of flatfish native to the North Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ... and North Atlantic oceans. Despite being in the family Pleuronectidae (popularly known as righteye flounders), all three species in the genus ''Platichthys'' are often "lefteyed", i.e. they lie on the sea bottom on their right side, with both eyes on the left side. Species There are currently three recognized species in this genus: References Further reading * Momigliano, M.; G.P.J. Denys; H. Jokinen; and J. Merilä (2018). Platichthys solemdali sp. nov. (Actinopterygii, Pleuronectiformes): A New Flounder Species From the Baltic Sea. Front. Mar. Sci. 5(225). Pleuronectidae {{Pleuronectiformes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutrophication
Eutrophication is the process by which an entire body of water, or parts of it, becomes progressively enriched with minerals and nutrients, particularly nitrogen and phosphorus. It has also been defined as "nutrient-induced increase in phytoplankton productivity". Water bodies with very low nutrient levels are termed oligotrophic and those with moderate nutrient levels are termed mesotrophic. Advanced eutrophication may also be referred to as dystrophic and hypertrophic conditions. Eutrophication can affect freshwater or salt water systems. In freshwater ecosystems it is almost always caused by excess phosphorus. In coastal waters on the other hand, the main contributing nutrient is more likely to be nitrogen, or nitrogen and phosphorus together. This depends on the location and other factors. When occurring naturally, eutrophication is a very slow process in which nutrients, especially phosphorus compounds and organic matter, accumulate in water bodies. These nutrients deriv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Warming
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is more rapid than previous changes, and is primarily caused by humans burning fossil fuels. Fossil fuel use, deforestation, and some agricultural and industrial practices increase greenhouse gases, notably carbon dioxide and methane. Greenhouse gases absorb some of the heat that the Earth radiates after it warms from sunlight. Larger amounts of these gases trap more heat in Earth's lower atmosphere, causing global warming. Due to climate change, deserts are expanding, while heat waves and wildfires are becoming more common. Increased warming in the Arctic has contributed to melting permafrost, glacial retreat and sea ice loss. Higher temperatures are also causing m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gulf Of Finland
The Gulf of Finland ( fi, Suomenlahti; et, Soome laht; rus, Фи́нский зали́в, r=Finskiy zaliv, p=ˈfʲinskʲɪj zɐˈlʲif; sv, Finska viken) is the easternmost arm of the Baltic Sea. It extends between Finland to the north and Estonia to the south, to Saint Petersburg in Russia to the east, where the river Neva drains into it. Other major cities around the gulf include Helsinki and Tallinn. The eastern parts of the Gulf of Finland belong to Russia, and some of Russia's most important oil harbors are located farthest in, near Saint Petersburg (including Primorsk). As the seaway to Saint Petersburg, the Gulf of Finland has been and continues to be of considerable strategic importance to Russia. Some of the environmental problems affecting the Baltic Sea are at their most pronounced in the shallow gulf. Proposals for a tunnel through the gulf have been made. Geography The gulf has an area of . The length (from the Hanko Peninsula to Saint Petersburg) is and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancylus Lake
Ancylus Lake is a name given by geologists to a large freshwater lake that existed in northern Europe approximately from 9500 to 8000 years B.C being in effect one of various predecessors to the modern Baltic Sea. Origin, evolution and demise The Ancylus Lake replaced the Yoldia Sea after the latter had been severed from its saline intake across a seaway along the Central Swedish lowland, roughly between Gothenburg and Stockholm. The cutoff was the result of isostatic rise being faster than the concurrent post-glacial sea level rise. In the words of Svante Björck the Ancylus Lake "is perhaps the most enigmatic (and discussed) of the many Baltic stages". The lake's outlet and elevation relative to sea-level was for long time surrounded by controversy. It is now known that the lake was above sea level, included Lake Vänern, and drained westward through three outlets at Göta Älv, Uddevalla and Otteid. As result of the continued isostatic uplift of Sweden, the outlets in cent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reproductive Isolation
The mechanisms of reproductive isolation are a collection of evolutionary mechanisms, behaviors and physiological processes critical for speciation. They prevent members of different species from producing offspring, or ensure that any offspring are sterile. These barriers maintain the integrity of a species by reducing gene flow between related species.Strickberger, M. 1978. ''Genética''. Omega, Barcelona, España, p.: 874-879. .Futuyma, D. 1998. ''Evolutionary biology'' (3ª edición). Sinauer, Sunderland. The mechanisms of reproductive isolation have been classified in a number of ways. Zoologist Ernst Mayr classified the mechanisms of reproductive isolation in two broad categories: pre-zygotic for those that act before fertilization (or before mating in the case of animals) and post-zygotic for those that act after it.Mayr, E. 1963. ''Animal species and evolution''. Harvard University Press, Cambridge. The mechanisms are genetically controlled and can appear in species whose ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neritic Zone
The neritic zone (or sublittoral zone) is the relatively shallow part of the ocean above the drop-off of the continental shelf, approximately in depth. From the point of view of marine biology it forms a relatively stable and well-illuminated environment for marine life, from plankton up to large fish and corals, while physical oceanography sees it as where the oceanic system interacts with the coast. Definition (marine biology), context, extra terminology In marine biology, the neritic zone, also called coastal waters, the coastal ocean or the sublittoral zone, refers to that zone of the ocean where sunlight reaches the ocean floor, that is, where the water is never so deep as to take it out of the photic zone. It extends from the low tide mark to the edge of the continental shelf, with a relatively shallow depth extending to about 200 meters (660 feet). Above the neritic zone lie the intertidal (or eulittoral) and supralittoral zones; below it the continental slope begi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelagic Zone
The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or water column between the surface of the sea and the bottom. Conditions in the water column change with depth: pressure increases; temperature and light decrease; salinity, oxygen, micronutrients (such as iron, magnesium and calcium) all change. Marine life is affected by bathymetry (underwater topography) such as the seafloor, shoreline, or a submarine seamount, as well as by proximity to the boundary between the ocean and the atmosphere at the ocean surface, which brings light for photosynthesis, predation from above, and wind stirring up waves and setting currents in motion. The pelagic zone refers to the open, free waters away from the shore, where marine life can swim freely in any direction unhindered by topographical constraints. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish Migration
Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres. Such migrations are usually done for better feeding or to reproduce, but in other cases the reasons are unclear. Fish migrations involve movements of schools of fish on a scale and duration larger than those arising during normal daily activities. Some particular types of migration are ''anadromous'', in which adult fish live in the sea and migrate into fresh water to spawn; and ''catadromous'', in which adult fish live in fresh water and migrate into salt water to spawn. Marine forage fish often make large migrations between their spawning, feeding and nursery grounds. Movements are associated with ocean currents and with the availability of food in different areas at different times of year. The migratory movements m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaël P
Gaël (Gallo: ''Gaèu'') is a commune in the Ille-et-Vilaine department in Brittany in northwestern France. It lies southwest of Rennes between Saint-Méen-le-Grand and Mauron. In the 18th century, a fair was held twice a year in August and October. Toponymy Old versions of the place-name include ''Guadel'' in 799, ''Wadel'' in 816, ''Vadel'' in 851, ''Wael'' in 1096, ''Gael'' as soon as 1112. Its Breton name is ''Gwazel'', that comes directly from ''Wadel > Gwadel > Gwazel'', in Breton intervocalic becomes like in ''mezo'' ″drunk″, Welsh ''meddw'' ″drunk″. In French intervocalic disappears totally : ''Wadel > Wael'' (Latin ''cadena'' > French ''chaine'' > English ''chain'') and initial Germanic ''w-'' became ''gu-'' ʷ(+ ''-a'') before becoming simply : ''Guadel > Gael'' (cf. Old French ''guarder'' > French ''garder'', English ''guard''). The symbol ''ë'' means in Modern French that the preceding ''a'' has to be pronounced : ''Ga-el'' aɛl(not ɛʲl Neverth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
