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Needle ice phenomena play a particularly significant role in patterned ground in periglacial environments. [8] The growth of needle ice lifts a detached, frozen soil crust riding on top of the layer of ice. When the crust and the ice melt, the soil surface settles back irregularly. This phenomenon is linked to erosion, particularly on ...
Photograph taken 21 March 2010 in Norwich, Vermont. Frost heaving (or a frost heave) is an upwards swelling of soil during freezing conditions caused by an increasing presence of ice as it grows towards the surface, upwards from the depth in the soil where freezing temperatures have penetrated into the soil (the freezing front or freezing boundary).
Soil containing high levels of organic materials are often more resistant to erosion, because the organic materials coagulate soil colloids and create a stronger, more stable soil structure. [45] The amount of water present in the soil before the precipitation also plays an important role, because it sets limits on the amount of water that can ...
Any natural process by which material such as soil and rocks is added to a landform or landmass, e.g. by the action of wind, water, ice, or gravity in transporting previously weathered surface material, which comes to rest when sufficient kinetic energy is lost and accumulates in layers of sediment.
The displacement of solids (sediment, soil, rock and other particles) usually by the agents of currents such as wind, water, or ice by downward or down-slope movement in response to gravity or by living organisms (in the case of bioerosion). erratic A piece of rock that deviates from the size and type of rock native to the area in which it rests.
Hydrotropism requires a root to bend from a drier to a wetter soil zone. Roots require water to grow so roots that happen to be in moist soil will grow and branch much more than those in dry soil. Roots cannot sense water inside intact pipes via hydrotropism and break the pipes to obtain the water. Roots cannot sense water several feet away via ...
Ice lenses are responsible for palsa (picture) growth. The basic condition for ice segregation and frost heaving is existence of a region in soil or porous rock which is relatively permeable, is in a temperature range which allows the coexistence of ice and water (in a premelted state), and has a temperature gradient across the region. [7]
(pl.) aboiteaux A sluice or conduit built beneath a coastal dike, with a hinged gate or a one-way valve that closes during high tide, preventing salt water from flowing into the sluice and flooding the land behind the dike, but remains open during low tide, allowing fresh water precipitation and irrigation runoff to drain from the land into the sea; or a method of land reclamation which relies ...