![Terracettes below Morgan's Hill - geograph](https://upload.wikimedia.org/wikipedia/commons/b/b7/Terracettes_below_Morgan%27s_Hill_-_geograph.org.uk_-_1345945.jpg)
A terracette is a
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, ...
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
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 character ...
and 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 terrestria ...
behaviour, 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 p ...
and 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 ...
including gelifluction
Gelifluction, very similar to solifluction, is the seasonal freeze-thaw action upon waterlogging topsoil
Topsoil is the upper layer of soil. It has the highest concentration of organic matter and microorganisms and is where most of the Eart ...
.[
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
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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 ...
near the 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 cerem ...
. 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
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 ...
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 terracettes, but further examination revealed places where they abruptly end at steep rock faces or at soils of different composition. Other sites show livestock trails cutting across terracettes. Geomorphologists Vincent and Clarke have also cast doubt about the ability of animals alone to create such regular steps or ridges.[
]
See also
* 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 deriv ...
References
External links
Geology and geomorphology
Slope landforms
Soil landforms
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