FISHERY BULLETIN: VOL. 72, NO. 2 



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A SON OJ FA1AA1J 



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Figure 6. — Fluctuations of (from top to bottom) chlorophyll 

 a, silicates, dissolved inorganic phosphates, and nitrites in 

 Goose Creek, 1966-1968. (Redrawn from Hair, 1968; Fazio 

 1969.) Solid line represents 1966-1967 data; dotted line repre- 

 sents 1967-1968 data. 



In general, the results of the Goose Creek 

 nutrient studies are similar to those carried on 

 in Chesapeake Bay by Flemer (1970) and Biggs 

 (1968). Particulate phosphates, silicates, and 

 chlorophyll a increased significantly. Concentra- 

 tions of nitrates, nitrites, and dissolved organic 

 and inorganic phosphates were not appreciably 

 different before and after dredging. 



Copeland and Dickens (1969) report that in 

 Maryland, Texas, and South Carolina there was 

 an initial diminution of phytoplankton produc- 

 tivity due to shading and a later enhancement 

 due to resuspension of nutrients from dredge spoil. 

 Flemer (1970) indicates that he found no demon- 

 strable effect of the deposition of fine sediments 

 from dredging on the production of phytoplankton 

 in Chesapeake Bay. 



There is no evidence that the release of nu- 

 trients from dredging produces an effect similar 

 to that described by Raymont (1947, 1949) 

 where the addition of fertilizer to small, enclosed 

 embayments raised the level of benthic pro- 

 ductivity up to 300% by stimulating production 

 of phytoplankton. 



Mechanical Analysis of the Sediment 



Sanders (1956) points out the great variability 

 in establishing criteria for the differentiation 

 of particles constituting the sediment. He ex- 

 pressed the composition of the sediment in terms 

 of the proportion of the particular component 

 which was either most predominant or most rele- 

 vant to the point he was making (e.g., Mulinia 

 lateralis is either absent or present in low num- 

 bers when the proportion of silt-clay in the sample 

 is greater than 40*7^). In the present study the 

 samples were sieved and the lighter fractions 

 analyzed by pipetting. Phi values were calculated 

 and eight fractions recorded, one for sand (up to 

 a maximum phi coefficient of 4.0), six for the 

 various fractions of silt (phi = 4.5-8.0) and one 

 for clay (phi = 9.0 and beyond). Data are recorded 

 in percent sand, silt, and clay to conform with 

 common practice. 



Three sets of sediment samples were obtained 

 during the course of the study. A preliminary 

 survey was performed in September 1966, using a 

 1 m Phleger corer at each of the permanent 

 sampling stations. Figure 7 delineates the sedi- 

 ment facies distribution compiled during this 

 survey. Also found on this map are the stations 



454 



