Diurnal Changes in Lake Systems

  • Robert G. Wetzel
  • Gene E. Likens


Environmental conditions may change markedly within aquatic ecosystems during a 24-h period. Solar radiation varies from high intensity at midday to darkness. Surface temperatures and concentrations of dissolved gases also may fluctuate between extremes of day and night, especially in shallow, littoral areas. Organisms within the lake may move vertically or otherwise relocate themselves in response to these environmental changes. For example, various species of Zooplankton undergo marked vertical migrations during a 24-h cycle [cf., Hutchinson (1967) and Wetzel (1983, 1999)]. These movements are keyed to light, food availability, and predation pressures. In this exercise, we shall examine some of the relationships between these factors and the vertical movements of Zooplankton in a lake.


Dissolve Oxygen Concentration Vertical Migration Diurnal Change Lake System Littoral Area 
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  1. Hutchinson, G.E. 1967. A Treatise on Limnology. Vol. 2. Introduction to Lake Biology and the Limnoplankton. Wiley, New York. 1115 pp.Google Scholar
  2. Pennak, R.W. 1943. An effective method of diagramming diurnal movements of Zooplankton organisms. Ecology 24:405–407.CrossRefGoogle Scholar
  3. Wetzel, R.G. 1983. Liminology. Saunders Coll., Philadelphia. 860 pp.Google Scholar
  4. Wetzel, R.G. 1999. Limnology: Lake and River Ecosystems. 3rd Ed. Academic Press, San Diego (in press).Google Scholar
  5. Worthington, E.B. 1931. Vertical movements of freshwater macroplankton. Int. Rev. ges. Hydrobiol. Hydrogr. 25:394–436.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2000

Authors and Affiliations

  • Robert G. Wetzel
    • 1
  • Gene E. Likens
    • 2
  1. 1.Department of Biology, College of Arts and SciencesUniversity of AlabamaTuscaloosaUSA
  2. 2.Institute of Ecosystem Studies, Cary ArboretumThe New York Botanical GardenMillbrookUSA

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