Diel abundance and productivity patterns of autotrophic picoplankton in the lower Chesapeake Bay

Diel studies associating phototrophic picoplankton abundance and productivity to tidal flow and pycnocline formation were conducted during summer and winter. Higher picoplankton concentrations and productivity were associated with waters above the pycnodine in summer, with picoplankton abundance highest during ebb tide when phycocyanin enriched Synechococcus sp. were dominant. In winter, greater concentrations and productivity occurred in bottom waters and during flood tide, when phycoerythrin enriched Synechococcus sp. were dominant.