Planktonic Micro—Communities in the Sea: biofluid mechanical view

It has long been known that marine planktonic organisms are patchily distributed at a variety of spatial scales (Steele, 1976, 1978; Haury et al, 1978). Until recently, however, most studies of plankton patchiness have focused on spatial scales larger than the order of 10 cm (vertical) and of 10 m (horizontal). Recently advances in instrumentation have now made it possible to examine patches smaller than 1 m in horizontal direction (Denman and Mackas, 1978; Platt, 1978). Evidence indicates that microscale patches as small as or smaller than i cm in diameter are common and persistent in the turbulent sea (Mitchell, 1988). These patches may have a significant role in ecosystem function. Most importantly, although organisms and nutrients are on average sparsely distributed in oceanic waters, their coassociation in micropatches could be key to energy and nutrient flows (McCarthy and Goldman, 1979).