1. The pelagic system : The most important finding in the pelagic 

 study was the sedimentation of oil. Thus, sediment traps should be a 

 standard instrument in the study of the environmental impact of oil 

 spills, wherever their deployment and retrieval are physically possible. 

 With deployment sooner (within 1-2 days after the spill) and a larger 

 number of traps, it would have been possible to make a much better 

 estimate of the amount of oil reaching the benthos--a measurement of 

 crucial importance in estimating the extent and duration of the impact 

 of oil on the ecosystem (also see section 1.6). 



Another crucial measurement in the pelagic zone is the composition 

 and concentration of oil in the water column. Where such measurements 

 can be made and tied to other observations, for example, the presence of 

 oil droplets in association with zooplankton (Chapter 4) , important 

 information on the mechanism of oil transport through the water column 

 can be produced. Due to the problems of sampling, however, it is not 

 yet practicable to survey large areas of the water for hydrocarbon 

 analysis in a way that is statistically adequate. If a proper sampler 

 can be devised (see section 1.6), its use will be of greatest value in 

 conjunction with plankton, bacteria, littoral, and sedimentation studies 

 to establish level of exposure as a basis for interpreting other phenomena. 



The study of plankton showed increases in bacterial and phytoplank- 

 ton biomass, but it failed to elucidate the mechanism behind the increase. 

 Higher sampling frequency, especially at the reference stations, might 

 have helped, as might more "frequency of dividing cells" (FDC), measure- 

 ments of bacterial growth rates. Clearly defined bacterial composition 

 studies would certainly improve the assumption that bacterial increases 

 are due to oleophilic species. Perhaps an equally important experiment 

 would be to analyze the feeding rate of zooplankton from the area. This 

 might demonstrate whether oil reaches the benthos mostly after ingestion 

 by zooplankton and incorporation into fecal pellets or by direct adsorp- 

 tion to detrital and mineral seston particles, which then sediment. The 

 relation between dispersed particles, suspended sediments, and zooplankton 

 feeding behavior should be investigated thoroughly. 



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