- Dimictic lake
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Lake zones Littoral zone Limnetic zone Profundal zone Benthic zone Lake stratification Epilimnion Metalimnion Hypolimnion Destratification Lake types Holomictic lake Monomictic lake Dimictic lake Polymictic lake Meromictic lake Amictic lake Aquatic ecosystems Wild fisheries Dimictic lakes are lakes that mix from top to bottom during two mixing periods each year. Dimictic lakes are holomictic, a category which includes all lakes which mix one or more times per year. During winter they are covered by ice. During summer they are thermally stratified, with temperature-derived density differences separating the warm surface waters (the epilimnion), from the colder bottom waters (the hypolimnion).
Typical mixing pattern for a dimictic lake
Mixing typically occurs during the spring and autumn, when the lake is "isothermal" (i.e., at the same temperature from the top to the bottom). At this time the water throughout the lake is about 4°C, and, in the absence of any temperature or density differences, the lake readily mixes from top to bottom. These lakes are common in regions with temperate climates.[1]
References
- ^ Lewis, William M., Jr. (1983). "A revised classification of lakes based on mixing". Canadian Journal of Fisheries and Aquatic Sciences 40 (10): 1779–1787. doi:10.1139/f83-207. http://cires.colorado.edu/limnology/pubs/pdfs/Pub058.pdf.
See also
External links
"Circulation: annual patterns of dimictic lakes" at Encyclopædia Britannica Online
Categories:- Geography terminology stubs
- Lakes
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