Vertical and horizontal distributions of dinoflagellate cysts in sediments1

Studies of the distribution of dinoflagellate resting cysts have typically focused on the flocculent layer at the sediment— water interface. Simple coring methods now reveal a wide variety of vertical distributions of cysts in different estuarine and nearshore environments, often with significant subsurface concentrations of viable cysts. Both subsurface and surface maxima are found in both coarse and fine sediments. The results have implications with respect to maps of cyst distribution, to correlations between the observed patterns and hydrographic or sedimentary parameters, and to assessments of the role of this life cycle stage in “seeding” dinoflagellate blooms.