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Acrotelm Catotelm
The acrotelm is one of two distinct layers in undisturbed peat bogs. It overlies the catotelm. The boundary between the two layers is defined by the transition from peat containing living plants (acrotelm) to peat containing dead plant material (catotelm). This typically coincides with the lowest level of the water table. To lower the water table before harvesting, ditching is performed first. Natural peatlands Fluctuations in the position of the water table in a peat bog occur within the acrotelm, and hence conditions may vary from aerobic to anaerobic with time. Where there are extensive geological fluctuations in the peatland surface, the depth of the acrotelm may change fundamentally over a couple of meters of distance. In general, the acrotelm has a higher hydraulic conductivity and a lower bulk density than the catotelm. Other characteristics are shared by these two zones. Mined peatlands After ditching, the acrotelm becomes thicker and more effective, drying the peat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peat 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 is another type of bog found in the forest of the Gulf Coast states in the United States.Watson, Geraldine Ellis (2000) ''Big Thicket Plant Ecology: An Introduction'', Third Edition (Temple Big Thicket Series #5). University of North Texas Press. Denton, Texas. 152 pp. Texas Parks and Wildlife. Ecological Mapping Systems of Texas:West Gulf Coastal Plain Seepage Swamp and Baygall. Retrieved 7 July 2020 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peat
Peat is an accumulation of partially Decomposition, decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, Moorland, moors, or muskegs. ''Sphagnum'' moss, also called peat moss, is one of the most common components in peat, although many other plants can contribute. The biological features of sphagnum mosses act to create a habitat aiding peat formation, a phenomenon termed 'habitat manipulation'. Soils consisting primarily of peat are known as histosols. Peat forms in wetland conditions, where flooding or stagnant water obstructs the flow of oxygen from the atmosphere, slowing the rate of decomposition. Peat properties such as organic matter content and saturated hydraulic conductivity can exhibit high spatial heterogeneity. Peatlands, particularly bogs, are the primary source of peat; although less common, other wetlands, including fens, pocosins and peat swamp forests, also deposit peat. Landscapes covered in peat are home to sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Table
The water table is the upper surface of the phreatic zone or zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with groundwater, which may be fresh, saline, or brackish, depending on the locality. It can also be simply explained as the depth below which the ground is saturated. The portion above the water table is the vadose zone. It may be visualized as the "surface" of the subsurface materials that are saturated with groundwater in a given vicinity. In coarse soils, the water table settles at the surface where the water Hydraulic head, pressure head is equal to the atmospheric pressure (where gauge pressure = 0). In soils where capillary action is strong, the water table is pulled upward, forming a capillary fringe. The groundwater may be from precipitation or from more distant groundwater flowing into the aquifer. In areas with sufficient precipitation, water infiltrates through pore spaces in the soil, passing through t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ditch
A ditch is a small to moderate trench created to channel water. A ditch can be used for drainage, to drain water from low-lying areas, alongside roadways or fields, or to channel water from a more distant source for plant irrigation. Ditches are commonly seen around farmland, especially in areas that have required drainage, such as The Fens in eastern England and much of the Netherlands. Roadside ditches may provide a hazard to motorists and cyclists, whose vehicles may crash into them and get damaged, flipped over, or stuck and cause major injury, especially in poor weather conditions and rural areas. Etymology In Anglo-Saxon, the word ''dïc'' already existed and was pronounced ("deek") in northern England and "deetch" in the south. The origins of the word lie in digging a trench and forming the upcast soil into a bank alongside it. This practice has meant that the name ''dïc'' was given to either the excavation or the bank, and evolved to both the words "dike"/" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acrotelm Catotelm
The acrotelm is one of two distinct layers in undisturbed peat bogs. It overlies the catotelm. The boundary between the two layers is defined by the transition from peat containing living plants (acrotelm) to peat containing dead plant material (catotelm). This typically coincides with the lowest level of the water table. To lower the water table before harvesting, ditching is performed first. Natural peatlands Fluctuations in the position of the water table in a peat bog occur within the acrotelm, and hence conditions may vary from aerobic to anaerobic with time. Where there are extensive geological fluctuations in the peatland surface, the depth of the acrotelm may change fundamentally over a couple of meters of distance. In general, the acrotelm has a higher hydraulic conductivity and a lower bulk density than the catotelm. Other characteristics are shared by these two zones. Mined peatlands After ditching, the acrotelm becomes thicker and more effective, drying the peat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subsidence
Subsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope movement. Processes that lead to subsidence include dissolution of underlying carbonate rock by groundwater; gradual compaction of sediments; withdrawal of fluid lava from beneath a solidified crust of rock; mining; pumping of subsurface fluids, such as groundwater or petroleum; or warping of the Earth's crust by tectonic forces. Subsidence resulting from tectonic deformation of the crust is known as tectonic subsidence and can create accommodation for sediments to accumulate and eventually lithify into sedimentary rock. Ground subsidence is of global concern to geologists, geotechnical engineers, surveyors, engineers, urban planners, landowners, and the public in general.National Research Council, 1991. ''Mitigating losses from land ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Conductivity
In science and engineering, hydraulic conductivity (, in SI units of meters per second), is a property of porous materials, soils and Rock (geology), rocks, that describes the ease with which a fluid (usually water) can move through the porosity, pore space, or fracture network. It depends on the intrinsic permeability (, unit: m) of the material, the degree of Water content, saturation, and on the density and viscosity of the fluid. Saturated hydraulic conductivity, , describes water movement through saturated media. By definition, hydraulic conductivity is the ratio of volume flux to Hydraulic head#Hydraulic gradient, hydraulic gradient yielding a quantitative measure of a saturated soil's ability to transmit water when subjected to a hydraulic gradient. Methods of determination There are two broad approaches for determining hydraulic conductivity: *In the ''empirical'' approach the hydraulic conductivity is correlated to soil properties like Porosity, pore-size and particle-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Part Of Waun Ddu Raised Bog - Geograph
Part, parts or PART may refer to: People *Part (surname) *Parts (surname) Arts, entertainment, and media *Part (music), a single strand or melody or harmony of music within a larger ensemble or a polyphonic musical composition *Part (bibliography), a sub-division of a volume or journal * ''Parts'' (book), a 1997 children's book by Tedd Arnold *Character (arts), in acting, a person or other being in a performed narrative Transportation *Pottstown Area Rapid Transit (PART), Pennsylvania, U.S. * Putnam Area Rapid Transit (PART), New York, U.S. *Piedmont Authority for Regional Transportation (PART), North Carolina, U.S. Other uses *Part (mathematics) or Mereology, the study of parts and the wholes they form *Part-of, the semantic relation of a part to the whole specific to linguistics *Spare part, an interchangeable part used for repair *Part number, identifier of a particular part design in engineering *Part (haircut), a hairstyle *Parts of Lincolnshire, geographic divisions of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ombrotrophic
Ombrotrophic ("cloud-fed"), from Ancient Greek ὄμβρος (''ómvros'') meaning "rain" and τροφή (''trofí'') meaning "food"), refers to Soil, soils or vegetation which receive all of their water and nutrients from precipitation, rather than from streams or springs. Such environments are hydrology, hydrologically isolated from the surrounding landscape, and since rain is acidic and very low in Plant nutrition, nutrients, they are home to organisms tolerant of acidic, low-nutrient environments. The vegetation of ombrotrophic peatlands is often bog, dominated by ''Sphagnum'' mosses. The hydrology of these environments are directly related to their climate, as precipitation is the water and nutrient source, and temperatures dictate how quickly water evaporates from these systems. Ombrotrophic circumstances may occur even in landscapes composed of limestone or other nutrient-rich substrates – for example, in high-rainfall areas, limestone boulders may be capped by acidic o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mire
A peatland is a type of wetland whose soils consist of Soil organic matter, organic matter from decaying plants, forming layers of peat. Peatlands arise because of incomplete decomposition of organic matter, usually litter from vegetation, due to Waterlogging (agriculture), water-logging and subsequent anoxic waters, anoxia. Peatlands are unusual landforms that derive mostly from biological rather than physical processes, and can take on characteristic shapes and surface patterning. The formation of peatlands is primarily controlled by climatic conditions such as precipitation and temperature, although terrain relief is a major factor as waterlogging occurs more easily on flatter ground and in basins. Peat formation typically initiates as a paludification of a mineral soil forests, terrestrialisation of lakes, or primary peat formation on bare soils on previously glaciated areas. A peatland that is actively forming peat is called a ''mire''. All types of mires share the common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raised Bog
Raised bogs, also called ombrotrophic bogs, are acidic, wet habitats that are poor in mineral salts and are home to flora and fauna that can cope with such extreme conditions. Raised bogs, unlike fens, are exclusively fed by precipitation (ombrotrophy) and from mineral salts introduced from the air. They thus represent a special type of bog, hydrologically, ecologically and in terms of their development history, in which the growth of peat mosses over centuries or millennia plays a decisive role. They also differ in character from blanket bogs which are much thinner and occur in wetter, cloudier climatic zones. Raised bogs are very threatened by peat cutting and pollution by mineral salts from the surrounding land (due to agriculture and Industrial sector, industry). The last great raised bog regions are found in western Siberia and Canada. Terminology The term ''raised bog'' derives from the fact that this type of bog rises in height over time as a result of peat formation. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
