Tidal resuspension in Buzzards Bay, Massachusetts: II. Seasonal changes in the size distribution of chlorophyll, particle concentration, carbon and nitrogen in resuspended particulate matter

Abstract

Seasonal changes in the particle size spectrum of suspended matter in near bottom water of Buzzards Bay was studied by fractional filtration. The greatest fraction of the total particulate organic carbon and particulate organic nitrogen throughout the year was less than 20 μm. The relative independence of the seasonal size distribution of particulate carbon to changes in the chlorophyll, as well as high carbon: nitrogen ratios during winter, suggest that large amounts of detritus are present in Buzzards Bay. Chlorophyll a distribution was dominated by nanoplankton in the spring and summer months when inorganic nutrients were low and zooplankton grazers abundant. The winter and fall phytoplankton blooms were dominated by individual and chain-forming diatoms greater than 53 μm. The dominance of nanoplankton and nanodetritus (<20 μm) in the suspended matter of Buzzards Bay suggests that the major source of nutrition for filter feeding zooplankton are small particles.