An Induced Mixing Experiment?

Abstract

As the diverse contributions to this volume show, there is now widespread recognition of the importance of tidal stirring as one of the fundamental influences on the shelf sea environment. Not only does it control the intensity of vertical mixing thus partitioning the shelf into mixed and stratified regions separated by fronts, but tidal stirring is also responsible for the resuspension of sediments which strongly influence the absorption and scattering of light in the water column. The impact of these physical processes on the biology has been the focus of considerable interdisciplinary effort in the last decade. During this period, in spite of rather slow progress in understanding the detail of vertical mixing processes and frontal dynamics, a substantial body of evidence has been assembled which suggests that the productivity and standing crop in the water column may be related to the level of tidal stirring. In particular there is some suggestive evidence that frontal zones are regions of generally higher primary production because they provide phytoplankton with a favourable balance of light and nutrients.