Structure-dependent, protistan grazing and its implication for the formation, maintenance and decline of plankton patches

Plankton distributions are frequently patchy and phytoplankton patches have long been suggested as important resources in otherwise nutritionally dilute environments. The present study confirms this hypothesis empirically in a coastal fjord with naturally forming phytoplankton patches and examines the implications for plankton distributions, abundance and rates of patch formation, maintenance and decline. Phytoplankton patches were identified using a CTD mounted fluorometer and sampled with a horizontally mounted 2 l Niskin bottle in 3 separate field seasons in summer 2007 and 2008 and spring 2009. We quantified chlaand macronutrient concentrations as well as phytoplankton growth and zooplankton (