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Hydrological measurements were limited to water temperature and salinity. 

 Analysis of surface sediments included particle-size distribution, carbon chem- 

 istry, and statistical properties of mean grain size, sorting, skewness, and 

 kurtosis. Average and extreme periods of water temperature and salinity were 

 recorded. Regional nearshore sediments proved to be fine sand, containing less 

 than 1 percent silt-clay, that was moderately well to well sorted, symmetrical 

 to coarsely skewed, and leptokurtic. Total carbon content averaged less than 

 0.30 percent, and most of that occurred in the form of carbonate deposits. Over 

 a postdredging study period of 1 year, sediment samples from borrow pits showed 

 little variation from these general features. 



In studies of the benthos, 362 species and 58,068 individuals were recorded 

 among lA invertebrate phyla and bony fishes. Dominant groups by species and 

 abundance included annelida, mollusca, and arthropoda (crustacea) . Faunal com- 

 parisons between dredged and undredged areas were made on the basis of species 

 richness and abundance, the Shannon-Weaver index of diversity (H'), Pielou's 

 index of equitability (J'), Morisita's index of faunal similarity (together with 

 matrices and classification diagrams derived from that index) , and two statisti- 

 cal derivations, based on diversity and abundance data, that were designed to 

 show sample-to-sample faunal variations and the time period required for faunal 

 recovery in borrow pits. Information obtained from these procedures showed that 

 recovery began soon after dredging and was complete, or nearly so, within 1 year. 



These results were similar in most respects to those from study of offshore 

 dredging elsewhere in comparable geographic settings. Even so, the need for 

 close association between ecological research and coastal engineering programs 

 is emphasized. 



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