Modeling Light Loss Versus UV-B Increase for Organisms Which Control Their Vertical Position in the Water Column
Quantitation of solar UV effects on aquatic systems is most often based on models which assume the exposed organisms are located in the water column in a manner independent of the incident solar UV (Zaneveld, 1975, Lorenzen, 1979 Hunter et al., this volume, and Smith and Baker, this volume). Planktonic organisms are in fact seldom static in the water; plants and animals move up and down in the water in complex ways which often show high correlations with the incident solar radiation (Barcelo and Calkins 1980 a & b; Barcelo and Calkins, 1979; Barcelo, 1980). Since solar UV has been demonstrated to be highly injurious, and is not a new agent in the environment, it is possible that a significant portion of the plankton control their position in such a way that they avoid overexposure to damaging solar UV radiation. Positioning control through swimming ability, bouyancy changes and utilization of turbulence or water currents is well known.
KeywordsWater Column Visible Light Euphotic Zone Incident Solar Radiation Swimming Ability
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