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Terracettes Below Morgan's Hill - Geograph
A terracette is a landform consisting of a hillside ridge arranged as part of sub-parallel "step-like sequences" of such ridges. Terracette occur on step hillsides and are regularly spaced. Various causes have been suggested to explain their origin including: animal trampling, vegetation and regolith behaviour, soil creep and solifluction including gelifluction. One explanation holds that terracettes are formed when saturated soil particles expand, then contract as they dry, causing them to move slowly downhill. An example of this is the manger near the Uffington White Horse. It may also be described as a small, irregular step-like formation on steep hillslopes, especially on those used for pasture which are formed by soil creep or erosion of surface soils exacerbated by the trampling of livestock such as sheep or cattle. Synonyms are: catstep cattle terracing, sheep or cattle track. Early investigators such as C. Darwin (1904) believed that animals grazing the hillsides caused t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terracettes Below Morgan's Hill - Geograph
A terracette is a landform consisting of a hillside ridge arranged as part of sub-parallel "step-like sequences" of such ridges. Terracette occur on step hillsides and are regularly spaced. Various causes have been suggested to explain their origin including: animal trampling, vegetation and regolith behaviour, soil creep and solifluction including gelifluction. One explanation holds that terracettes are formed when saturated soil particles expand, then contract as they dry, causing them to move slowly downhill. An example of this is the manger near the Uffington White Horse. It may also be described as a small, irregular step-like formation on steep hillslopes, especially on those used for pasture which are formed by soil creep or erosion of surface soils exacerbated by the trampling of livestock such as sheep or cattle. Synonyms are: catstep cattle terracing, sheep or cattle track. Early investigators such as C. Darwin (1904) believed that animals grazing the hillsides caused t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landform
A landform is a natural or anthropogenic land feature on the solid surface of the Earth or other planetary body. Landforms together make up a given terrain, and their arrangement in the landscape is known as topography. Landforms include hills, mountains, canyons, and valleys, as well as shoreline features such as bays, peninsulas, and seas, including submerged features such as mid-ocean ridges, volcanoes, and the great ocean basins. Physical characteristics Landforms are categorized by characteristic physical attributes such as elevation, slope, orientation, stratification, rock exposure and soil type. Gross physical features or landforms include intuitive elements such as berms, mounds, hills, ridges, cliffs, valleys, rivers, peninsulas, volcanoes, and numerous other structural and size-scaled (e.g. ponds vs. lakes, hills vs. mountains) elements including various kinds of inland and oceanic waterbodies and sub-surface features. Mountains, hills, plateaux, and plains are t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegetation
Vegetation is an assemblage of plant species and the ground cover they provide. It is a general term, without specific reference to particular taxa, life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader than the term ''flora'' which refers to species composition. Perhaps the closest synonym is plant community, but ''vegetation'' can, and often does, refer to a wider range of spatial scales than that term does, including scales as large as the global. Primeval redwood forests, coastal mangrove stands, sphagnum bogs, desert soil crusts, roadside weed patches, wheat fields, cultivated gardens and lawns; all are encompassed by the term ''vegetation''. The vegetation type is defined by characteristic dominant species, or a common aspect of the assemblage, such as an elevation range or environmental commonality. The contemporary use of ''vegetation'' approximates that of ecologist Frederic Clements' term earth cover, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regolith
Regolith () is a blanket of unconsolidated, loose, heterogeneous superficial deposits covering solid rock. It includes dust, broken rocks, and other related materials and is present on Earth, the Moon, Mars, some asteroids, and other terrestrial planets and moons. Etymology The term ''regolith'' combines two Greek words: (), 'blanket', and (), 'rock'. The American geologist George P. Merrill first defined the term in 1897, writing: Earth Earth's regolith includes the following subdivisions and components: * soil or pedolith * alluvium and other transported cover, including that transported by aeolian, glacial, marine, and gravity flow processes. * "saprolith'", generally divided into the ** ''upper saprolite'': completely oxidised bedrock ** ''lower saprolite'': chemically reduced partially weathered rocks ** ''saprock'': fractured bedrock with weathering restricted to fracture margins * volcanic ash and lava flows that are interbedded with unconsolidated material * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Creep
Downhill creep, also known as soil creep or commonly just creep, is a type of creep characterized by the slow, downward progression of rock and soil down a low grade slope; it can also refer to slow deformation of such materials as a result of prolonged pressure and stress. Creep may appear to an observer to be continuous, but it really is the sum of numerous minute, discrete movements of slope material caused by the force of gravity. Friction, being the primary force to resist gravity, is produced when one body of material slides past another offering a mechanical resistance between the two which acts to hold objects (or slopes) in place. As slope on a hill increases, the gravitational force that is perpendicular to the slope decreases and results in less friction between the material that could cause the slope to slide. Overview Water is a very important factor when discussing soil deformation and movement. For instance, a sandcastle will only stand up when it is made with da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solifluction
Solifluction is a collective name for gradual processes in which a mass moves down a slope ("mass wasting") related to freeze-thaw activity. This is the standard modern meaning of solifluction, which differs from the original meaning given to it by Johan Gunnar Andersson in 1906. Origin and evolution of the concept In the original sense it meant the movement of waste saturated in water found in periglacial regions. However it was later discovered that various slow waste movements in periglacial regions did not require saturation in water, but were rather associated to freeze-thaw processes. The term solifluction was appropriated to refer to these slow processes, and therefore excludes rapid periglacial movements. In slow periglacial solifluction there are not clear gliding planes, and therefore skinflows and active layer detachments are not included in the concept. On the other hand, movement of waste saturated in water can occur in any humid climate, and therefore this kind of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gelifluction
Gelifluction, very similar to solifluction, is the seasonal freeze-thaw action upon waterlogging topsoils which induces downslope movement. Gelifluction is prominent in periglacial Periglaciation (adjective: "periglacial", also referring to places at the edges of glacial areas) describes geomorphic processes that result from seasonal thawing of snow in areas of permafrost, the runoff from which refreezes in ice wedges and o ... regions where snow falls during six to eight months of the year. In spring, the snow and ice melt, and the landscape is effectively inundated with half a year's worth of rainfall in the space of a couple of days. The top soil becomes waterlogged, and flows like a liquid. Because the wet soil behaves like a fluid, gelifluction is a form of mass movement that can occur on slopes with a slope angle of less than half a degree. Landforms The most distinctive landforms created by gelifluction include gelifluction lobes and gelifluction benches. The former refe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manger
__NOTOC__ A manger or trough is a rack for fodder, or a structure or feeder used to hold food for animals. The word comes from the Old French ''mangier'' (meaning "to eat"), from Latin ''mandere'' (meaning "to chew"). Mangers are mostly used in livestock raising and generally found at stables and farmhouses. They are also used to feed wild animals, e.g., in nature reserves. A similar trough providing drinking water for domestic or non-domestic animals is a watering trough and may be part of a larger watering structure called abreuvoir. The manger in Christianity The manger is also associated with nativity scenes where Mary and Joseph, forced by necessity to stay in a room for animals instead of a guest room, used a manger as a makeshift crib for the Baby Jesus. ( el, φάτνη ''phatnē''; Luke 2:7). Gallery File:Devil's_Farmhouse,_Mellieha.jpeg, 18th century limestone mangers at The Devil's Farmhouse in Mellieha, Malta. File:Donkey eating.jpg, Donkey eating apples from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uffington White Horse
The Uffington White Horse is a prehistoric hill figure, long, formed from deep trenches filled with crushed white chalk. The figure is situated on the upper slopes of White Horse Hill in the English civil parish of Uffington (in the ceremonial county of Oxfordshire and historic county of Berkshire), some east of Swindon, south of the town of Faringdon and a similar distance west of the town of Wantage; or south of Uffington. The hill forms a part of the scarp of the Berkshire Downs and overlooks the Vale of White Horse to the north. The best views of the figure are obtained from the air, or from directly across the Vale, particularly around the villages of Great Coxwell, Longcot, and Fernham. The Uffington White Horse was created some time between 1380 and 550 , during the late Bronze Age or early Iron Age. The site is owned and managed by the National Trust and is a scheduled monument. ''The Guardian'' stated in 2003 that "for more than 3,000 years, the Uff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animals who are raised for consumption, and sometimes used to refer solely to farmed ruminants, such as cattle, sheep, goats and pigs. Horses are considered livestock in the United States. The USDA classifies pork, veal, beef, and lamb (mutton) as livestock, and all livestock as red meat. Poultry and fish are not included in the category. The breeding, maintenance, slaughter and general subjugation of livestock, called '' animal husbandry'', is a part of modern agriculture and has been practiced in many cultures since humanity's transition to farming from hunter-gatherer lifestyles. Animal husbandry practices have varied widely across cultures and time periods. It continues to play a major economic and cultural role in numerous communities. Lives ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biuletyn Peryglacjalny
''Biuletyn Peryglacjalny'' was a scientific journal covering research on periglacial geomorphology. It was established in 1954 in Łódź by Polish geomorphologist Jan Dylik, who was its editor-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility for its operations and policies. The highest-ranking editor of a publication may also be titled editor, managing ... until 1972. The journal ceased publication after 39 issues in 2000, after having played an important role in the development of periglacial geomorphology. References 1954 establishments in Poland Earth and atmospheric sciences journals Geomorphology journals Defunct journals Publications established in 1954 Publications disestablished in 2000 Multilingual journals Annual journals {{Geomorphology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Downland
Downland, chalkland, chalk downs or just downs are areas of open chalk hills, such as the North Downs. This term is used to describe the characteristic landscape in southern England where chalk is exposed at the surface. The name "downs" is derived from the Old English word dun, meaning "hill". Distribution The largest area of downland in southern England is formed by Salisbury Plain, mainly in Wiltshire. To the southwest, downlands continue via Cranborne Chase into Dorset as the Dorset Downs and southwards through Hampshire as the Hampshire Downs onto the Isle of Wight. To the northeast, downlands continue along the Berkshire Downs and Chiltern Hills through parts of Berkshire, Oxfordshire, Buckinghamshire, Hertfordshire, Bedfordshire and into Cambridgeshire. To the east downlands are found north of the Weald in Surrey, Kent and part of Greater London, forming the North Downs. To the southeast the downlands continue into West Sussex and East Sussex as the South Downs. Similar cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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