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active layer

active layer A seasonally thawed surface layer, between a few centimetres and about 3 m thick, that lies above the permanently frozen ground in a periglacial environment. It may be subject to considerable expansion on freezing because of the water contained, and this is especially the case if silt-sized particles dominate, with important engineering implications. See also Mollisols and permafrost.

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"active layer." A Dictionary of Ecology. . Encyclopedia.com. 25 Sep. 2018 <http://www.encyclopedia.com>.

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"active layer." A Dictionary of Ecology. . Retrieved September 25, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/active-layer-0

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active layer

active layer A seasonally thawed surface soil layer, between a few centimetres and about 3 m thick, that lies above the permanently frozen horizon in a periglacial environment. It may be subject to considerable expansion on freezing, especially if silt-sized particles dominate, and during the melt it may become very mobile. See also MOLLISOLS.

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"active layer." A Dictionary of Plant Sciences. . Encyclopedia.com. 25 Sep. 2018 <http://www.encyclopedia.com>.

"active layer." A Dictionary of Plant Sciences. . Encyclopedia.com. (September 25, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/active-layer-1

"active layer." A Dictionary of Plant Sciences. . Retrieved September 25, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/active-layer-1

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active layer

active layer Seasonally thawed surface layer between a few centimetres and about 3 m thick, lying above the permanently frozen ground in a periglacial environment. It may be subject to considerable expansion on freezing, especially if silt-sized particles dominate, with important engineering implications. See also MOLLISOLS; and PERMAFROST.

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"active layer." A Dictionary of Earth Sciences. . Encyclopedia.com. 25 Sep. 2018 <http://www.encyclopedia.com>.

"active layer." A Dictionary of Earth Sciences. . Encyclopedia.com. (September 25, 2018). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/active-layer

"active layer." A Dictionary of Earth Sciences. . Retrieved September 25, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/active-layer

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Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

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American Psychological Association

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Notes:
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