83-423: Bog is a wetland of mosses or lichens over waterlogged peat. Bog or Bogs may also refer to: Bog A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials – often mosses , typically sphagnum moss. It is one of the four main types of wetlands . Other names for bogs include mire , mosses, quagmire, and muskeg ; alkaline mires are called fens . A bayhead
166-456: A fen (or, on acidic substrates, valley bog), to a carr , as silt or peat accumulates within the lake. Eventually, peat builds up to a level where the land surface is too flat for ground or surface water to reach the center of the wetland. This part, therefore, becomes wholly rain-fed (ombrotrophic), and the resulting acidic conditions allow the development of bog (even if the substrate is non-acidic). The bog continues to form peat, and over time
249-467: A half-life of 3.7 million years, Mn with a half-life of 312.2 days, and Mn with a half-life of 5.591 days. All of the remaining radioactive isotopes have half-lives of less than three hours, and the majority of less than one minute. The primary decay mode in isotopes lighter than the most abundant stable isotope, Mn, is electron capture and the primary mode in heavier isotopes is beta decay . Manganese also has three meta states . Manganese
332-409: A magnesia nigra (the black ore) from magnesia alba (a white ore, also from Magnesia, also useful in glassmaking). Michele Mercati called magnesia nigra manganesa , and finally the metal isolated from it became known as manganese ( German : Mangan ). The name magnesia eventually was then used to refer only to the white magnesia alba (magnesium oxide), which provided the name magnesium for
415-497: A broad definition: Because all bogs have peat, they are a type of peatland. As a peat-producing ecosystem, they are also classified as mires , along with fens. Bogs differ from fens, in that fens receive water and nutrients from mineral-rich surface or groundwater, while bogs receive water and nutrients from precipitation. Because fens are supplied with mineral-rich water, they tend to range from slightly acidic to slightly basic, while bogs are always acidic because precipitation lacks
498-812: A butterfly called the bog copper ( Lycaena epixanthe ). In Ireland, the viviparous lizard , the only known reptile in the country, dwells in bogland. The United Kingdom in its Biodiversity Action Plan establishes bog habitats as a priority for conservation. Russia has a large reserve system in the West Siberian Lowland . The highest protected status occurs in Zapovedniks ( IUCN category IV); Gydansky and Yugansky are two prominent examples. Bogs are fragile ecosystems, and have been deteriorating quickly, as archaeologists and scientists have been recently finding. Bone material found in bogs has had accelerated deterioration from first analyses in
581-607: A lesser extent as rhodochrosite ( MnCO 3 ). The most important manganese ore is pyrolusite ( MnO 2 ). Other economically important manganese ores usually show a close spatial relation to the iron ores, such as sphalerite . Land-based resources are large but irregularly distributed. About 80% of the known world manganese resources are in South Africa; other important manganese deposits are in Ukraine, Australia, India, China, Gabon and Brazil. According to 1978 estimate,
664-534: A number of governmental and conservation agencies. They can provide habitat for mammals, such as caribou , moose , and beavers , as well as for species of nesting shorebirds, such as Siberian cranes and yellowlegs . Bogs contain species of vulnerable reptilians such as the bog turtle . Bogs even have distinctive insects; English bogs give a home to a yellow fly called the hairy canary fly ( Phaonia jaroschewskii ), and bogs in North America are habitat for
747-442: A primitive cubic structure with 20 atoms per unit cell at two types of sites, which is as complex as that of any other elemental metal. It is easily obtained as a metastable phase at room temperature by rapid quenching. It does not show magnetic ordering , remaining paramagnetic down to the lowest temperature measured (1.1 K). Gamma manganese (γ-Mn) forms when heated above 1,370 K (1,100 °C; 2,010 °F). It has
830-527: A roothold. The result is a narrow, permanently wet habitat. After drying, peat is used as a fuel , and it has been used that way for centuries. More than 20% of home heat in Ireland comes from peat, and it is also used for fuel in Finland, Scotland, Germany, and Russia. Russia is the leading exporter of peat for fuel, at more than 90 million metric tons per year. Ireland's Bord na Móna ("peat board")
913-399: A rubber additive; and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In
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#1732775833845996-402: A shallow dome of bog peat develops into a raised bog. The dome is typically a few meters high in the center and is often surrounded by strips of fen or other wetland vegetation at the edges or along streamsides where groundwater can percolate into the wetland. The various types of raised bog may be divided into: In cool climates with consistently high rainfall (on more than c. 235 days a year),
1079-447: A simple face-centered cubic structure (four atoms per unit cell). When quenched to room temperature it converts to β-Mn, but it can be stabilized at room temperature by alloying it with at least 5 percent of other elements (such as C, Fe, Ni, Cu, Pd or Au), and these solute-stabilized alloys distort into a face-centered tetragonal structure. Delta manganese (δ-Mn) forms when heated above 1,406 K (1,130 °C; 2,070 °F) and
1162-436: Is MnO 2 . It is the dark brown pigment of many cave drawings but is also a common ingredient in dry cell batteries. Complexes of Mn(IV) are well known, but they require elaborate ligands . Mn(IV)-OH complexes are an intermediate in some enzymes , including the oxygen evolving center (OEC) in plants. Simple derivatives Mn are rarely encountered but can be stabilized by suitably basic ligands. Manganese(III) acetate
1245-430: Is a chemical element ; it has symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron . Manganese was first isolated in the 1770s. It is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels . It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent; as
1328-466: Is a brown pigment for paint and is a constituent of natural umber . Tetravalent manganese is used as an activator in red-emitting phosphors . While many compounds are known which show luminescence , the majority are not used in commercial application due to low efficiency or deep red emission. However, several Mn activated fluorides were reported as potential red-emitting phosphors for warm-white LEDs. But to this day, only K 2 SiF 6 :Mn
1411-552: Is a commonly used laboratory reagent because of its oxidizing properties; it is used as a topical medicine (for example, in the treatment of fish diseases). Solutions of potassium permanganate were among the first stains and fixatives to be used in the preparation of biological cells and tissues for electron microscopy. Aside from various permanganate salts, Mn(VII) is represented by the unstable, volatile derivative Mn 2 O 7 . Oxyhalides (MnO 3 F and MnO 3 Cl) are powerful oxidizing agents . The most prominent example of Mn in
1494-494: Is a silvery-gray metal that resembles iron. It is hard and very brittle, difficult to fuse, but easy to oxidize. Manganese and its common ions are paramagnetic . Manganese tarnishes slowly in air and oxidizes ("rusts") like iron in water containing dissolved oxygen. Naturally occurring manganese is composed of one stable isotope , Mn. Several radioisotopes have been isolated and described, ranging in atomic weight from 46 u ( Mn) to 72 u ( Mn). The most stable are Mn with
1577-549: Is also seen in the mineral rhodochrosite ( manganese(II) carbonate ). Manganese(II) commonly exists with a high spin, S = 5/2 ground state because of the high pairing energy for manganese(II). There are no spin-allowed d–d transitions in manganese(II), which explain its faint color. Manganese forms a large variety of organometallic derivatives, i.e., compounds with Mn-C bonds. The organometallic derivatives include numerous examples of Mn in its lower oxidation states, i.e. Mn(−III) up through Mn(I). This area of organometallic chemistry
1660-574: Is an oxidant useful in organic synthesis . Solid compounds of manganese(III) are characterized by its strong purple-red color and a preference for distorted octahedral coordination resulting from the Jahn-Teller effect . A particularly common oxidation state for manganese in aqueous solution is +2, which has a pale pink color. Many manganese(II) compounds are known, such as the aquo complexes derived from manganese(II) sulfate (MnSO 4 ) and manganese(II) chloride (MnCl 2 ). This oxidation state
1743-544: Is another type of bog found in the forest of the Gulf Coast states in the United States. They are often covered in heath or heather shrubs rooted in the sphagnum moss and peat. The gradual accumulation of decayed plant material in a bog functions as a carbon sink . Bogs occur where the water at the ground surface is acidic and low in nutrients. A bog usually is found at a freshwater soft spongy ground that
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#17327758338451826-464: Is attractive because Mn is inexpensive and of relatively low toxicity. Of greatest commercial interest is "MMT", methylcyclopentadienyl manganese tricarbonyl , which is used as an anti-knock compound added to gasoline (petrol) in some countries. It features Mn(I). Consistent with other aspects of Mn(II) chemistry, manganocene ( Mn(C 5 H 5 ) 2 ) is high-spin. In contrast, its neighboring metal iron forms an air-stable, low-spin derivative in
1909-421: Is dominant in a given soil. At pH values less than 6 or under anaerobic conditions, Mn(II) dominates, while under more alkaline and aerobic conditions, Mn(III,IV) oxides and hydroxides predominate. These effects of soil acidity and aeration state on the form of Mn can be modified or controlled by microbial activity. Microbial respiration can cause both the oxidation of Mn to the oxides, and it can cause reduction of
1992-545: Is found throughout the world's oceans, 90% of which originates from hydrothermal vents. Particulate Mn develops in buoyant plumes over an active vent source, while the dMn behaves conservatively. Mn concentrations vary between the water columns of the ocean. At the surface, dMn is elevated due to input from external sources such as rivers, dust, and shelf sediments. Coastal sediments normally have lower Mn concentrations, but can increase due to anthropogenic discharges from industries such as mining and steel manufacturing, which enter
2075-458: Is low spin, which contrasts with the high spin character of its precursor, MnBr 2 (dmpe) 2 ( dmpe = (CH 3 ) 2 PCH 2 CH 2 P(CH 3 ) 2 ). Polyalkyl and polyaryl derivatives of manganese often exist in higher oxidation states, reflecting the electron-releasing properties of alkyl and aryl ligands. One example is [Mn(CH 3 ) 6 ] . The origin of the name manganese is complex. In ancient times, two black minerals were identified from
2158-400: Is made up of decayed plant matter which is known as peat. They are generally found in cooler northern climates and are formed in poorly draining lake basins. In contrast to fens , they derive most of their water from precipitation rather than mineral-rich ground or surface water. Water flowing out of bogs has a characteristic brown colour, which comes from dissolved peat tannins . In general,
2241-408: Is mainly mined in South Africa, Australia, China, Gabon, Brazil, India, Kazakhstan, Ghana, Ukraine and Malaysia. For the production of ferromanganese , the manganese ore is mixed with iron ore and carbon, and then reduced either in a blast furnace or in an electric arc furnace. The resulting ferromanganese has a manganese content of 30–80%. Pure manganese used for the production of iron-free alloys
2324-501: Is part of the iron group of elements, which are thought to be synthesized in large stars shortly before the supernova explosion. Mn decays to Cr with a half-life of 3.7 million years. Because of its relatively short half-life, Mn is relatively rare, produced by cosmic rays impact on iron . Manganese isotopic contents are typically combined with chromium isotopic contents and have found application in isotope geology and radiometric dating . Mn–Cr isotopic ratios reinforce
2407-424: Is produced by leaching manganese ore with sulfuric acid and a subsequent electrowinning process. A more progressive extraction process involves directly reducing (a low grade) manganese ore by heap leaching . This is done by percolating natural gas through the bottom of the heap; the natural gas provides the heat (needs to be at least 850 °C) and the reducing agent (carbon monoxide). This reduces all of
2490-442: Is stable up to the manganese melting point of 1,519 K (1,250 °C; 2,270 °F). It has a body-centered cubic structure (two atoms per cubic unit cell). Common oxidation states of manganese are +2, +3, +4, +6, and +7, although all oxidation states from −3 to +7 have been observed. Manganese in oxidation state +7 is represented by salts of the intensely purple permanganate anion MnO − 4 . Potassium permanganate
2573-405: Is unusual among elemental metals in having a very complex unit cell, with 58 atoms per cell (29 atoms per primitive unit cell) in four different types of site. It is paramagnetic at room temperature and antiferromagnetic at temperatures below 95 K (−178 °C). Beta manganese (β-Mn) forms when heated above the transition temperature of 973 K (700 °C; 1,290 °F). It has
Bog (disambiguation) - Misplaced Pages Continue
2656-412: Is used as a reagent in organic chemistry for the oxidation of benzylic alcohols (where the hydroxyl group is adjacent to an aromatic ring ). Manganese dioxide has been used since antiquity to oxidize and neutralize the greenish tinge in glass from trace amounts of iron contamination. MnO 2 is also used in the manufacture of oxygen and chlorine and in drying black paints. In some preparations, it
2739-675: The Haraldskær Woman and Tollund Man in Denmark, and Lindow man found at Lindow Common in England. The Tollund Man was so well preserved that when the body was discovered in 1950, the discoverers thought it was a recent murder victim and researchers were even able to tell the last meal that the Tollund Man ate before he died: porridge and fish. This process happens because of the low oxygen levels of bogs in combination with
2822-496: The Middle Ages until modern times and is evident in 14th-century glass from Venice . Because it was used in glassmaking, manganese dioxide was available for experiments by alchemists, the first chemists. Ignatius Gottfried Kaim (1770) and Johann Glauber (17th century) discovered that manganese dioxide could be converted to permanganate , a useful laboratory reagent. Kaim also may have reduced manganese dioxide to isolate
2905-1318: The Northern Hemisphere . The world's largest wetland is the peat bogs of the Western Siberian Lowlands in Russia , which cover more than a million square kilometres. Large peat bogs also occur in North America, particularly the Hudson Bay Lowland and the Mackenzie River Basin. They are less common in the Southern Hemisphere, with the largest being the Magellanic moorland , comprising some 44,000 square kilometres (17,000 sq mi) in southern South America. Sphagnum bogs were widespread in northern Europe but have often been cleared and drained for agriculture. A paper led by Graeme T. Swindles in 2019 showed that peatlands across Europe have undergone rapid drying in recent centuries owing to human impacts including drainage, peat cutting and burning. A 2014 expedition leaving from Itanga village, Republic of
2988-602: The Spartan steel exceptionally hard. Around the beginning of the 19th century, manganese was used in steelmaking and several patents were granted. In 1816, it was documented that iron alloyed with manganese was harder but not more brittle. In 1837, British academic James Couper noted an association between miners' heavy exposure to manganese and a form of Parkinson's disease . In 1912, United States patents were granted for protecting firearms against rust and corrosion with manganese phosphate electrochemical conversion coatings, and
3071-464: The barley used in making Scotch whisky . Once the peat has been extracted it can be difficult to restore the wetland , since peat accumulation is a slow process. More than 90% of the bogs in England have been damaged or destroyed. In 2011 plans for the elimination of peat in gardening products were announced by the UK government. The peat in bogs is an important place for the storage of carbon. If
3154-523: The ocean floor has 500 billion tons of manganese nodules . Attempts to find economically viable methods of harvesting manganese nodules were abandoned in the 1970s. In South Africa, most identified deposits are located near Hotazel in the Northern Cape Province , ( Kalahari manganese fields ), with a 2011 estimate of 15 billion tons. In 2011 South Africa produced 3.4 million tons, topping all other nations. Manganese
3237-476: The +6 oxidation state is the green anion manganate , [MnO 4 ] . Manganate salts are intermediates in the extraction of manganese from its ores. Compounds with oxidation states +5 are somewhat elusive, and often found associated to an oxide (O ) or nitride (N ) ligand. One example is the blue anion hypomanganate [MnO 4 ] . Mn(IV) is somewhat enigmatic because it is common in nature but far rarer in synthetic chemistry. The most common Mn ore, pyrolusite ,
3320-416: The 1940s. This has been found to be from fluctuations in ground water and increase in acidity in lower areas of bogs that is affecting the rich organic material. Many of these areas have been permeated to the lowest levels with oxygen, which dries and cracks layers. There have been some temporary solutions to try and fix these issues, such as adding soil to the tops of threatened areas, yet they do not work in
3403-491: The 2020s. The real mission of Hughes Glomar Explorer was to raise a sunken Soviet submarine, the K-129 , with the goal of retrieving Soviet code books. An abundant resource of manganese in the form of manganese nodules found on the ocean floor. These nodules, which are composed of 29% manganese, are located along the ocean floor . The environmental impacts of nodule collection are of interest. Dissolved manganese (dMn)
Bog (disambiguation) - Misplaced Pages Continue
3486-479: The 20th century, manganese dioxide was widely used as the cathodic for commercial disposable dry batteries of both the standard (zinc–carbon) and alkaline types. Manganese is essential to iron and steel production by virtue of its sulfur -fixing, deoxidizing , and alloying properties. This application was first recognized by the British metallurgist Robert Forester Mushet (1811–1891) who, in 1856, introduced
3569-523: The Congo , discovered a peat bog "as big as England " which stretches into neighboring Democratic Republic of Congo . Like all wetlands, it is difficult to rigidly define bogs for a number of reasons, including variations between bogs, the in-between nature of wetlands as an intermediate between terrestrial and aquatic ecosystems, and varying definitions between wetland classification systems. However, there are characteristics common to all bogs that provide
3652-471: The Solar System. Four allotropes (structural forms) of solid manganese are known, labeled α, β, γ and δ, and occurring at successively higher temperatures. All are metallic, stable at standard pressure, and have a cubic crystal lattice, but they vary widely in their atomic structures. Alpha manganese (α-Mn) is the equilibrium phase at room temperature. It has a body-centered cubic lattice and
3735-567: The alloys particularly useful in harsh automotive and industrial environments. Manganese oxide and sulfate are components of fertilizers. In the year 2000, an estimated 20,000 tons of these compounds were used in fertilizers in the US alone. A comparable amount of Mn compounds was also used in animal feeds. Methylcyclopentadienyl manganese tricarbonyl is an additive in some unleaded gasoline to boost octane rating and reduce engine knocking . Manganese(IV) oxide (manganese dioxide, MnO 2 )
3818-518: The combination of low nutrient levels and waterlogging. Sphagnum is generally abundant, along with ericaceous shrubs. The shrubs are often evergreen, which may assist in conservation of nutrients. In drier locations, evergreen trees can occur, in which case the bog blends into the surrounding expanses of boreal evergreen forest. Sedges are one of the more common herbaceous species. Carnivorous plants such as sundews ( Drosera ) and pitcher plants (for example Sarracenia purpurea ) have adapted to
3901-400: The deepest part of the valley, and a stream may run through the surface of the bog. Valley bogs may develop in relatively dry and warm climates, but because they rely on ground or surface water, they only occur on acidic substrates. These develop from a lake or flat marshy area, over either non-acidic or acidic substrates. Over centuries there is a progression from open lake, to a marsh, to
3984-558: The dissolved minerals (e.g. calcium , magnesium , carbonate ) that act to buffer the natural acidity of atmospheric carbon dioxide . Geography and geology both impact the hydrology: as groundwater mineral content reflects the bedrock geology, there can be great deal of variability in some common ions (e.g. manganese , iron ) while proximity to coastal areas is associated with higher sulfate and sodium concentrations. There are many highly specialized animals, fungi, and plants associated with bog habitat. Most are capable of tolerating
4067-460: The edges of acidic lakes. The bog vegetation, mostly sphagnum moss anchored by sedges (such as Carex lasiocarpa ), forms a floating mat approximately half a meter thick on the surface of water or above very wet peat. White spruce ( Picea glauca ) may grow in this bog regime. Walking on the surface causes it to move – larger movements may cause visible ripples on the surface, or they may even make trees sway. The bog mat may eventually spread across
4150-481: The element, in the form of Spiegeleisen . Manganese comprises about 1000 ppm (0.1%) of the Earth's crust and is the 12th most abundant element. Soil contains 7–9000 ppm of manganese with an average of 440 ppm. The atmosphere contains 0.01 μg/m . Manganese occurs principally as pyrolusite ( MnO 2 ), braunite (Mn Mn 6 )SiO 12 ), psilomelane (Ba,H 2 O) 2 Mn 5 O 10 , and to
4233-518: The evidence from Al and Pd for the early history of the Solar System . Variations in Cr/ Cr and Mn/Cr ratios from several meteorites suggest an initial Mn/ Mn ratio, which indicate that Mn–Cr isotopic composition must result from in situ decay of Mn in differentiated planetary bodies. Hence, Mn provides additional evidence for nucleosynthetic processes immediately before coalescence of
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#17327758338454316-491: The form of ferrocene ( Fe(C 5 H 5 ) 2 ). When conducted under an atmosphere of carbon monoxide , reduction of Mn(II) salts gives dimanganese decacarbonyl Mn 2 (CO) 10 , an orange and volatile solid. The air-stability of this Mn(0) compound (and its many derivatives) reflects the powerful electron-acceptor properties of carbon monoxide. Many alkene complexes and alkyne complexes are derived from Mn 2 (CO) 10 . In Mn(CH 3 ) 2 (dmpe) 2 , Mn(II)
4399-465: The free element when it was isolated much later. Manganese dioxide, which is abundant in nature, has long been used as a pigment. The cave paintings in Gargas that are 30,000 to 24,000 years old are made from the mineral form of MnO 2 pigments. Manganese compounds were used by Egyptian and Roman glassmakers, either to add to, or remove, color from glass. Use as "glassmakers soap" continued through
4482-553: The global average. Because bogs and other peatlands are carbon sinks, they are releasing large amounts of greenhouse gases as they warm up. These changes have resulted in a severe decline of biodiversity and species populations of peatlands throughout Northern Europe. Bog habitats may develop in various situations, depending on the climate and topography. Bogs may be classified on their topography, proximity to water, method of recharge, and nutrient accumulation. These develop in gently sloping valleys or hollows. A layer of peat fills
4565-421: The ground surface may remain waterlogged for much of the time, providing conditions for the development of bog vegetation . In these circumstances, bog develops as a layer "blanketing" much of the land, including hilltops and slopes. Although a blanket bog is more common on acidic substrates, under some conditions it may also develop on neutral or even alkaline ones, if abundant acidic rainwater predominates over
4648-469: The groundwater. A blanket bog can occur in drier or warmer climates, because under those conditions hilltops and sloping ground dry out too often for peat to form – in intermediate climates a blanket bog may be limited to areas which are shaded from direct sunshine. In periglacial climates a patterned form of blanket bog may occur, known as a string bog . In Europe, these mostly very thin peat layers without significant surface structures are distributed over
4731-840: The headwaters of large rivers. Even the enormous Yangtze River arises in the Ruoergai peatland near its headwaters in Tibet . Blueberries , cranberries , cloudberries , huckleberries , and lingonberries are harvested from the wild in bogs. Bog oak , wood that has been partially preserved by bogs, has been used in the manufacture of furniture . Sphagnum bogs are also used for outdoor recreation, with activities including ecotourism and hunting. For example, many popular canoe routes in northern Canada include areas of peatland. Some other activities, such as all-terrain vehicle use, are especially damaging to bogs. The anaerobic environment and presence of tannic acids within bogs can result in
4814-623: The high acidity. These anaerobic conditions lead to some of the best-preserved mummies and offer much archeological insight into society as far as 8,000 years back. Céide Fields in County Mayo in Ireland, a 5,000-year-old neolithic farming landscape has been found preserved under a blanket bog , complete with field walls and hut sites. One ancient artifact found in various bogs is bog butter , large masses of fat, usually in wooden containers. These are thought to have been food stores of both butter and tallow . Manganese Manganese
4897-521: The hills and valleys of Ireland, Scotland, England, and Norway. In North America, blanket bogs occur predominantly in Canada east of Hudson Bay . These bogs are often still under the influence of mineral soil water (groundwater). Blanket bogs do not occur north of the 65th latitude in the northern hemisphere. A quaking bog , schwingmoor , or swingmoor is a form of floating bog occurring in wetter parts of valley bogs and raised bogs and sometimes around
4980-410: The human brain, the manganese is bound to manganese metalloproteins , most notably glutamine synthetase in astrocytes . It is familiar in the laboratory in the form of the deep violet salt potassium permanganate . It occurs at the active sites in some enzymes . Of particular interest is the use of a Mn-O cluster , the oxygen-evolving complex , in the production of oxygen by plants. Manganese
5063-497: The long-term. Extreme weather like dry summers are likely the cause, as they lower precipitation and the groundwater table. It is speculated that these issues will only increase with a rise in global temperature and climate change. Since bogs take thousands of years to form and create the rich peat that is used as a resource, once they are gone they are extremely hard to recover. Arctic and sub-Arctic circles where many bogs are warming at 0.6 °C per decade, an amount twice as large as
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#17327758338455146-526: The low fertility and cool climate result in relatively slow plant growth, but decay is even slower due to low oxygen levels in saturated bog soils. Hence, peat accumulates. Large areas of the landscape can be covered many meters deep in peat. Bogs have distinctive assemblages of animal, fungal, and plant species, and are of high importance for biodiversity , particularly in landscapes that are otherwise settled and farmed. Bogs are widely distributed in cold, temperate climes , mostly in boreal ecosystems in
5229-408: The low-nutrient conditions by using invertebrates as a nutrient source. Orchids have adapted to these conditions through the use of mycorrhizal fungi to extract nutrients. Some shrubs such as Myrica gale (bog myrtle) have root nodules in which nitrogen fixation occurs, thereby providing another supplemental source of nitrogen. Bogs are recognized as a significant/specific habitat type by
5312-412: The manganese content reaches 4%, the embrittlement of the steel becomes a dominant feature. The embrittlement decreases at higher manganese concentrations and reaches an acceptable level at 8%. Steel containing 8 to 15% of manganese has a high tensile strength of up to 863 MPa. Steel with 12% manganese was discovered in 1882 by Robert Hadfield and is still known as Hadfield steel (mangalloy) . It
5395-503: The manganese ore to manganese oxide (MnO), which is a leachable form. The ore then travels through a grinding circuit to reduce the particle size of the ore to between 150 and 250 μm, increasing the surface area to aid leaching. The ore is then added to a leach tank of sulfuric acid and ferrous iron (Fe ) in a 1.6:1 ratio. The iron reacts with the manganese dioxide (MnO 2 ) to form iron hydroxide (FeO(OH)) and elemental manganese (Mn). This process yields approximately 92% recovery of
5478-460: The manganese. For further purification, the manganese can then be sent to an electrowinning facility. In 1972, the CIA 's Project Azorian , through billionaire Howard Hughes , commissioned the ship Hughes Glomar Explorer with the cover story of harvesting manganese nodules from the sea floor. That triggered a rush of activity to collect manganese nodules, which was not actually practical until
5561-633: The metal, but that is uncertain. By the mid-18th century, the Swedish chemist Carl Wilhelm Scheele used manganese dioxide to produce chlorine . First, hydrochloric acid , or a mixture of dilute sulfuric acid and sodium chloride was made to react with manganese dioxide, and later hydrochloric acid from the Leblanc process was used and the manganese dioxide was recycled by the Weldon process . The production of chlorine and hypochlorite bleaching agents
5644-573: The metals and organic compounds can then cause them to be oxidized while the Mn(III,IV) oxides are reduced to Mn (e.g., Cr to Cr(VI) and colorless hydroquinone to tea-colored quinone polymers). Manganese is essential to iron and steel production by virtue of its sulfur -fixing, deoxidizing , and alloying properties. Manganese has no satisfactory substitute in these applications in metallurgy. Steelmaking , including its ironmaking component, has accounted for most manganese demand, presently in
5727-524: The ocean from river inputs. Surface dMn concentrations can also be elevated biologically through photosynthesis and physically from coastal upwelling and wind-driven surface currents. Internal cycling such as photo-reduction from UV radiation can also elevate levels by speeding up the dissolution of Mn-oxides and oxidative scavenging, preventing Mn from sinking to deeper waters. Elevated levels at mid-depths can occur near mid-ocean ridges and hydrothermal vents. The hydrothermal vents release dMn enriched fluid into
5810-441: The oxides to the divalent cation. The Mn(III,IV) oxides exist as brownish-black stains and small nodules on sand, silt, and clay particles. These surface coatings on other soil particles have high surface area and carry negative charge. The charged sites can adsorb and retain various cations, especially heavy metals (e.g., Cr , Cu , Zn , and Pb ). In addition, the oxides can adsorb organic acids and other compounds. The adsorption of
5893-475: The peat decays, carbon dioxide would be released to the atmosphere, contributing to global warming. Undisturbed, bogs function as a carbon sink . As one example, the peatlands of the former Soviet Union were calculated to be removing 52 Tg of carbon per year from the atmosphere. Therefore, the rewetting of drained peatlands may be one of the most cost-effective ways to mitigate climate change. Peat bogs are also important in storing fresh water, particularly in
5976-576: The process has seen widespread use ever since. The invention of the Leclanché cell in 1866 and the subsequent improvement of batteries containing manganese dioxide as cathodic depolarizer increased the demand for manganese dioxide. Until the development of batteries with nickel–cadmium and lithium, most batteries contained manganese. The zinc–carbon battery and the alkaline battery normally use industrially produced manganese dioxide because naturally occurring manganese dioxide contains impurities. In
6059-400: The range of 85% to 90% of the total demand. Manganese is a key component of low-cost stainless steel . Often ferromanganese (usually about 80% manganese) is the intermediate in modern processes. Small amounts of manganese improve the workability of steel at high temperatures by forming a high-melting sulfide and preventing the formation of a liquid iron sulfide at the grain boundaries. If
6142-481: The regions of the Magnetes (either Magnesia , located within modern Greece, or Magnesia ad Sipylum , located within modern Turkey). They were both called magnes from their place of origin, but were considered to differ in sex. The male magnes attracted iron, and was the iron ore now known as lodestone or magnetite , and which probably gave us the term magnet . The female magnes ore did not attract iron, but
6225-613: The remarkable preservation of organic material. Finds of such material have been made in Slovenia , Denmark , Germany , Ireland , Russia , and the United Kingdom. Some bogs have preserved bog-wood, such as ancient oak logs useful in dendrochronology . They have yielded extremely well-preserved bog bodies , with hair, organs, and skin intact, buried there thousands of years ago after apparent Germanic and Celtic human sacrifice . Excellent examples of such human specimens include
6308-415: The same basic reaction, but a different electrolyte mixture. In 2002, more than 230,000 tons of manganese dioxide was used for this purpose. Copper alloys of manganese, such as Manganin , are commonly found in metal element shunt resistors used for measuring relatively large amounts of current. These alloys have very low temperature coefficient of resistance and are resistant to sulfur. This makes
6391-401: The water surface to cover bays or even entire small lakes. Bogs at the edges of lakes may become detached and form floating islands . A cataract bog is a rare ecological community formed where a permanent stream flows over a granite outcropping. The sheeting of water keeps the edges of the rock wet without eroding the soil, but in this precarious location, no tree or large shrub can maintain
6474-589: The water. The dMn can then travel up to 4,000 km due to the microbial capsules present, preventing exchange with particles, lowing the sinking rates. Dissolved Mn concentrations are even higher when oxygen levels are low. Overall, dMn concentrations are normally higher in coastal regions and decrease when moving offshore. Manganese occurs in soils in three oxidation states: the divalent cation, Mn and as brownish-black oxides and hydroxides containing Mn (III,IV), such as MnOOH and MnO 2 . Soil pH and oxidation-reduction conditions affect which of these three forms of Mn
6557-482: Was a large consumer of manganese ores. Scheele and others were aware that pyrolusite (mineral form of manganese dioxide) contained a new element. Johan Gottlieb Gahn isolated an impure sample of manganese metal in 1774, which he did by reducing the dioxide with carbon . The manganese content of some iron ores used in Greece led to speculations that steel produced from that ore contains additional manganese, making
6640-452: Was one of the first companies to mechanically harvest peat, which is being phased out. The other major use of dried peat is as a soil amendment (sold as moss peat or sphagnum peat ) to increase the soil's capacity to retain moisture and enrich the soil. It is also used as a mulch . Some distilleries , notably in the Islay whisky-producing region, use the smoke from peat fires to dry
6723-572: Was used for British military steel helmets and later by the U.S. military. Manganese is used in production of alloys with aluminium. Aluminium with roughly 1.5% manganese has increased resistance to corrosion through grains that absorb impurities which would lead to galvanic corrosion . The corrosion-resistant aluminium alloys 3004 and 3104 (0.8 to 1.5% manganese) are used for most beverage cans . Before 2000, more than 1.6 million tonnes of those alloys were used; at 1% manganese, this consumed 16,000 tonnes of manganese. Manganese(IV) oxide
6806-414: Was used in the original type of dry cell battery as an electron acceptor from zinc, and is the blackish material in carbon–zinc type flashlight cells. The manganese dioxide is reduced to the manganese oxide-hydroxide MnO(OH) during discharging, preventing the formation of hydrogen at the anode of the battery. The same material also functions in newer alkaline batteries (usually battery cells), which use
6889-438: Was used to decolorize glass. This female magnes was later called magnesia , known now in modern times as pyrolusite or manganese dioxide . Neither this mineral nor elemental manganese is magnetic. In the 16th century, manganese dioxide was called manganesum (note the two Ns instead of one) by glassmakers, possibly as a corruption and concatenation of two words, since alchemists and glassmakers eventually had to differentiate
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