poorly sorted (station 3, experimental). Skewness values were characteristic 

 for five samples (symmetrical to coarsely skewed), and the other seven samples 

 fit the strongly coarse-skewed classification and were about equally divided 

 between the control and experimental samples. The normal, or leptokurtic 

 condition, was found in nine samples. Of the remaining three, the experimental 

 sample from station 4 and the control sample from station 6 were mesokurtic, 

 while the experimental sample from station 3 was platykurtic. 



Although sedimentological conditions in some experimental samples varied 

 from the base-line criteria until late 1977, large variations were confined to 

 borrow pit sediments at station 1 within 2 months after dredging. During that 

 period, properties which may have been limiting to benthos were high silt-clay 

 and organic carbon content. 



Diver reports between 18 August (10 days after dredging) and 4 October 1976, 

 stated that the station 1 borrow pit was 3 to 5 meters deep and had very dark 

 surface sediments of an extremely soft, silty texture. Initially no surface 

 signs of benthic life (burrows, mounds, or trails) were reported. Within the 

 next month, sediments had become firmer and sandier; signs of infauna activity 

 were conspicuous, crabs and other epibenthos were numerous, and a variety of 

 fishes was observed. After 12 months, and on the last dive at station 1 in 

 November 1977, divers concluded that borrow pits had filled to within a meter 

 of surrounding bottom, and that sediments inside were still finer, darker, and 

 less compact than sediments outside, but marine life appeared similar in control 

 and experimental areas. 



4. Benthos. 



The checklist of organisms in Appendix B contains about 362 organisms at 

 the species level, representing 14 invertebrate phyla and the vertebrate class, 

 Osteichthyes (bony fishes). Of this number, Annelida had 152 species (42 per- 

 cent), Arthropoda had 108 (30 percent), and there were 69 mollusks (19 percent). 

 The remaining 33 species (9 percent) were divided among 11 groups: Cnidaria, 

 Platyhelminthes, Nemertinea, Nematoda, Phoronida, Brachiopoda, Sipunculida, 

 Echiurida, Echinodermata, Hemichordata, and Cephalochordata. 



Species counts from each station showed a total of 58,068 individuals 

 collected. On a percentage basis, more than half were annelids (55 percent), 

 19 percent were mollusks, 18 percent were arthropods, Cnidaria and Cephalochordata 

 each accounted for 2 percent, Nematoda and Echinodermata both had 1 percent, 

 and the other seven groups contained 2 percent, collectively. For the three 

 major phyla, species that were numerically dominant in one or more of the base- 

 line or control site collections are given in Table 3. 



All station data for richness, quantitative abundance, diversity (H'), and 

 equitability (J') were tabulated by base-line, control, and experimental sample 

 categories (Tables 4, 5, and 6). Graphic analyses of Morisita's Index and 

 stability are given in Appendixes D, E, and F. 



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