Behaviour of Planktonic Coelenterates in Temperature and Salinity Discontinuity Layers
In an earlier paper (Arai 1973) I described the response of Sarsia tubulosa and Pleurobrachia pileus to discontinuities between upper layers of lower salinity water and lower layers of high salinity water. Both species aggregated actively to salinity discontinuities of as little as 2%. Under fjord conditions where such a response might be ecologically significant the halocline is usually accompanied by a thermocline. The present paper describes further experiments investigating responses to discontinuity layers, particularly those involving temperature discontinuities.
KeywordsHigh Salinity Water Temperature Discontinuity Discontinuity Layer Overhead Light Lower Density Water
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