The significance of thin layers aquatic plankton communities

Thin layers of plankton are increasingly in the focus of marine research, since new information on how organisms are distributed in the water column may change the way we perceive and model the dynamics of species interactions. Horizontal aggregations on larger scales are easy to confirm using standard equipment, while fine- and micro-scale layers are difficult to identify. This project will use a Video Plankton Recorder to study the vertical structure of plankton communities in the water column. The inst rument records images, which are subsequently identified to species or genus, and related to hydrographic data and chlorophyll fluorescence recorded within centimeters of the images. We expect to be able to identify thin layers on micro- and fine scales, and describe extent and persistent of layers, species composition, and relationship with physical and biological environmental variables. We hope to relate our findings to hypotheses about predator-regulated habitat choice, and to make assessments regardi ng the significance of thin layers for trophic interactions in aquatic systems.