The Distribution of Trace Metals in Long Island Sound Sediments

The primary control on the trace-metal concentrations is the grain size of the sediment. This can be seen by comparing the trace-metal maps with a grain-size distribution map (Fig. 10) for the Sound. The sand-rich sediments have the lowest trace-metal content. There is, however, an im- 

A number of cores collected from central Long Island Sound have been analyzed for trace metals as a function of sediment depth (Thomson et al., 1975 Turekian, 1979 Benninger et al., 1979). They show roughly the same patterns for Cu, Zn, and Pb (Fig. 11) a roughly exponential decrease in concentration with depth. At greater depths there are occasional peaks of high concentrations. 

As Fig. 11 shows, there is some variability in the integrated trace-element contents of cores from central Long Island Sound. These sediments are not located near intense sources of trace metals nor are there major grain-size differences. As we will show later, the differences in both metal concentrations and inventories can be related primarily to the intensity and depth of biological mixing of the sediment column. 

Trace-Metal Distributions in Mussels and Oysters Index of the Composition of Suspended Particles 

Mussels and oysters (epifauna) are filter feeders which attach to hard surfaces. Their isolation from the sediment means that their trace-metal compositions are likely to be reflective, primarily, of the suspended material in the water. In this section, therefore, the data available on trace-metal concentrations in mussels and oysters from the Connecticut shore are reviewed. 

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The Distribution of Trace Metals in Long Island Sound Sediments.137... 

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