is essential for photosynthesis. In the sea, nitrogen is introduced from 

 decomposition of biomaterial, primarily as ammonia, NH3 , which is then 

 oxidized to nitrite, [N02~), and finally to nitrate, CNO3") . Under 

 natural conditions, nitrogen compounds are exhausted first from the 

 marine environment, thus making nitrogen a limiting factor. 



Waste materials dumped in the Bight contribute significant amounts 

 of nutrients. Decomposition of organic matter dumped in the area reduces 

 complex protein molecules to nitrates, phosphates, carbon dioxide, and 

 water. Nutrients exist in both the sediments and the overlying waters 

 of the Bight dumping grounds in above-natural concentrations. Avail- 

 able nutrients are dissolved in the water, absorbed on the pelagic 

 particulate system, or are included in the sediments. The sediments of 

 the dumping grounds collected for the referenced studies were not analyzed 

 for nutrient content, but it is expected that these are in a state of 

 dynamic equilibrium with those in the water phase, and could contribute 

 to the available nutrient supply if other environmental variables were 

 changed. Nutrient release from the sediments could depend on such 

 factors as circulation of overlying waters, oxygen supply, and on the 

 presence of rooted algae such as mycrophytes which are able to use these 

 nutrients directly from the sediment phase. 



Waters of the dumping grounds were analyzed for phosphorus by SHL. 

 They found concentrations up to 5.64 microgram-atom per liter (yg-at/1) . 

 Other nutrient values reported by SHL for the sewage sludge dump were 

 often unusually high; the reported N:P ratio was unusually low. SHL use 

 of phosphorus as a tracer of water mass movement was questioned by the 

 SAC. The data presented by SHL appeared insufficent in time and space to 

 allow proper tracing (SAC, 1972). According to the SAC, it would be 

 necessary to analyze samples of water before, during, and after dumping 

 to estimate the dispersion of nutrients. 



The high concentration of phosphorus observed in the area could be 

 due to recent dumps. Concentration of more than 2 yg-at/1 orthophosphorus 

 found in the surface waters of the Irsh Sea was considered extraordinary 

 by Jones and Folkard (1971). Ketchum (1969) suggested an upper limit of 

 2.8 yg-at/1 for defining unpolluted coastal waters. The amount reported 

 by SHL in the dumping grounds of the Bight is about twice the maximum 

 value suggested by Ketchum for unpolluted waters. It has not been 

 demonstrated that high concentrations of phosphate are particularly 

 critical for open marine environments. Higher phosphate values which 

 may be of concern, have been reported for closed estuarine areas of the 

 N.Y. Bight. Ryther and Dunstan (1971) reported a value of 7.0 yg-at/1 

 inorganic phosphorus in Moriches Bay, Long Island, which was associated 

 with pollution from nearby duck farms. 



The effect of additional nutrients on water quality can be better 

 assessed by considering its direct effect upon primary productivity, 

 and^ (more specifically) on chlorophyll production. It is expected that 

 enrichment of the waters of the Bight in nutrients such as phosphorus, 

 resulting from dumping of sewage sludge, could have a beneficial effect 



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