Najas Marina
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Najas Marina
''Najas marina'' is a species of aquatic plant known by the common names spiny water nymph, spiny naiad and holly-leaved naiad. It is an extremely widespread species, reported across Europe, Asia, Africa, Australia, the Americas and many oceanic islands. It can be found in many types of freshwater and brackish aquatic habitat, including bodies of alkaline water. Description ''Najas marina'' is an annual producing a slender, branching stem up to 40 or 45 centimeters in maximum length. The evenly spaced leaves are up to 4 centimeters long, 1 to 3 millimeters wide, and edged in tiny sawlike teeth. The leaf has prickles along its midvein. Minute stalkless, green flowers occur in the leaf axils. The plant is dioecious, with male and female flower types occurring on separate individuals. In the British Isles it is possible that only female plants occur. It flowers in mid-summer. Varieties and subspecies A long list of varietal and subspecific names have been proposed over the yea ...
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Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern Taxonomy (biology), taxonomy". Many of his writings were in Latin; his name is rendered in Latin as and, after his 1761 ennoblement, as . Linnaeus was born in Råshult, the countryside of Småland, in southern Sweden. He received most of his higher education at Uppsala University and began giving lectures in botany there in 1730. He lived abroad between 1735 and 1738, where he studied and also published the first edition of his ' in the Netherlands. He then returned to Sweden where he became professor of medicine and botany at Uppsala. In the 1740s, he was sent on several journeys through Sweden to find and classify plants and animals. In ...
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Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabia (including the Arabian Peninsula and Bahrain), Asia Minor (Asian part of Turkey except Hatay Province), East Thrace (European part of Turkey), Egypt, Iran, the Levant (including Ash-Shām and Cyprus), Mesopotamia (modern-day Iraq), and the Socotra Archipelago (a part of Yemen). The term came into widespread usage as a replacement of the term Near East (as opposed to the Far East) beginning in the early 20th century. The term "Middle East" has led to some confusion over its changing definitions, and has been viewed by some to be discriminatory or too Eurocentric. The region includes the vast majority of the territories included in the closely associated definition of Western Asia (including Iran), but without the South Caucasus, and additionally includes all of Egypt (not just the Sinai Region) and all of Turkey (not just the part barring East Thrace). ...
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Aquatic Plants
Aquatic plants are plants that have adapted to living in aquatic environments ( saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that grows in or near water and is either emergent, submergent, or floating. In lakes and rivers macrophytes provide cover for fish, substrate for aquatic invertebrates, produce oxygen, and act as food for some fish and wildlife. Macrophytes are primary producers and are the basis of the food web for many organisms. They have a significant effect on soil chemistry and light levels as they slow down the flow of water and capture pollutants and trap sediments. Excess sediment will settle into the benthos aided by the reduction of flow rates caused by the presence of plant stems, leaves and roots. Some plants have the capability of absorbing pollutants into their tissue. Seaweeds are multicellular marine algae and, although their ecolog ...
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Najas
''Najas'', the water-nymphs or naiads, is a genus of aquatic plants. It is cosmopolitan in distribution, first described for modern science by Linnaeus in 1753. Until 1997, it was rarely placed in the Hydrocharitaceae,Angiosperm Phylogeny Group (2003). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II". ''Botanical Journal of the Linnean Society'' 141(4): 399-436. (Available onlineAbstractFull text (HTML)Full text (PDF) and was often taken as constituting (by itself) the family Najadaceae. ;Species # '' Najas affinis'' Rendle - South America, Senegal, Guinea-Bissau # '' Najas ancistrocarpa'' A.Braun ex Magnus - China, Japan, Taiwan # '' Najas arguta'' Kunth - Cuba, Costa Rica, Panama, South America # '' Najas australis'' Bory ex Rendle - India, Madagascar, Mauritius, KwaZulu-Natal, Seychelles # '' Najas baldwinii'' Horn - West Africa # '' Najas brevistyla'' Rendle - Assam # '' Najas browniana'' Rendle - southern ...
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Poland
Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populous member state of the European Union. Warsaw is the nation's capital and largest metropolis. Other major cities include Kraków, Wrocław, Łódź, Poznań, Gdańsk, and Szczecin. Poland has a temperate transitional climate and its territory traverses the Central European Plain, extending from Baltic Sea in the north to Sudeten and Carpathian Mountains in the south. The longest Polish river is the Vistula, and Poland's highest point is Mount Rysy, situated in the Tatra mountain range of the Carpathians. The country is bordered by Lithuania and Russia to the northeast, Belarus and Ukraine to the east, Slovakia and the Czech Republic to the south, and Germany to the west. It also shares maritime boundaries with Denmark a ...
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West Carpathians
The Western Carpathians are a mountain range and geomorphological province that forms the western part of the Carpathian Mountains. The mountain belt stretches from the Low Beskids range of the Eastern Carpathians along the border of Poland with Slovakia toward the Moravian region of the Czech Republic and the Austrian Weinviertel. In the south the North Hungarian Mountains cover northern Hungary. The area of the Western Carpathians comprises about 70,000 km². The highest elevation is the Gerlachovský štít (2,655m). Geographical definition Most of the perimeter of the Western Carpathians is quite sharply defined by valleys. To the northwest and north they are separated from the Bohemian Massif by the Forecarpathian Lowland and the Lesser Poland Upland; to the west the Moravian Gate leads over to the Sudetes. To the south the mountain chain falls away towards the Pannonian Plain, a large plain situated between the Alps, the Dinaric Alps, and the main mass of the Eas ...
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Middle Miocene
The Middle Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene. The sub-epoch lasted from 15.97 ± 0.05 Ma to 11.608 ± 0.005 Ma (million years ago). During this period, a sharp drop in global temperatures took place. This event is known as the Middle Miocene Climate Transition. For the purpose of establishing European Land Mammal Ages The European Land Mammal Mega Zones (abbreviation: ELMMZ, more commonly known as European land mammal ages or ELMA) are zones in rock layers that have a specific assemblage of fossils (biozones) based on occurrences of fossil assemblages of Europ ... this sub-epoch is equivalent to the Astaracian age. External links GeoWhen Database - Middle Miocene .02 02 * * {{geochronology-stub ...
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Borehole
A borehole is a narrow shaft bored in the ground, either vertically or horizontally. A borehole may be constructed for many different purposes, including the extraction of water ( drilled water well and tube well), other liquids (such as petroleum), or gases (such as natural gas). It may also be part of a geotechnical investigation, environmental site assessment, mineral exploration, temperature measurement, as a pilot hole for installing piers or underground utilities, for geothermal installations, or for underground storage of unwanted substances, e.g. in carbon capture and storage. Importance Engineers and environmental consultants use the term ''borehole'' to collectively describe all of the various types of holes drilled as part of a geotechnical investigation or environmental site assessment (a so-called Phase II ESA). This includes holes advanced to collect soil samples, water samples or rock cores, to advance ''in situ'' sampling equipment, or to install monitoring ...
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Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ...
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Hickling Broad
Hickling Broad is a nature reserve 4 km south-east of Stalham, north-east of Norwich in Norfolk. It is managed by the Norfolk Wildlife Trust. It is a National Nature Reserve and part of the Upper Thurne Broads and Marshes Site of Special Scientific Interest and Hickling Broad and Horsey Mere Nature Conservation Review site, Grade I. It is in the Norfolk Coast Area of Outstanding Natural Beauty, and part of the Broadland Ramsar site and Special Protection Area, and The Broads Special Area of Conservation. It is the broad with the largest surface area, and the water is slightly brackish, due to its proximity to the sea.''Inland Waterways of Great Britain'', Jane Cumberlidge, (2009), Imray Laurie Norie and Wilson, The navigation channel is only 1.5 m deep, with much of the broad being shallower; it is 1.4 km2, making it one of the largest expanses of open water in East Anglia. Ecology It has the largest reed-bed in England and supports rare waterweeds such as the ...
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Mesoeutrophic
The Trophic State Index (TSI) is a classification system designed to rate water bodies based on the amount of biological productivity they sustain. Although the term "trophic index" is commonly applied to lakes, any surface water body may be indexed. The TSI of a water body is rated on a scale from zero to one hundred. Under the TSI scale, water bodies may be defined as: * oligotrophic (TSI 0–40, having the least amount of biological productivity, "good" water quality); * mesotrophic (TSI 40–60, having a moderate level of biological productivity, "fair" water quality); or * eutrophic to hypereutrophic (TSI 60–100, having the highest amount of biological productivity, "poor" water quality). The quantities of nitrogen, phosphorus, and other biologically useful nutrients are the primary determinants of a water body's TSI. Nutrients such as nitrogen and phosphorus tend to be limiting resources in standing water bodies, so increased concentrations tend to result in increased p ...
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