Table 24-4. 



Comparisons of Phytoplankton in the Microcosms and in 

 Narragansett Bay at the GSO Dock During 

 the Replicability Experiment. 



NOTE: Similarity indices for the comparison of bay with all microcosms and 

 for microcosm 3 with all other microcosms. Shannon index of diversity (H) for 

 the microcosms and the bay. 



While we do not have concurrent data on nutrients and chlorophyll from 

 more than one station in Narragansett Bay, the results of a year-long survey at 

 13 stations in the bay taken in 1972-73 are available. Data from three of these 

 in the lower west passage of the bay are shown in Figure 24-5. The data set 

 from the bay is in most respects similar to that from the MERL microcosms. 

 Chlorophyll concentrations indicated a bloom in November in both the tanks 

 and the bay which did not occur in 1972. Ammonia concentrations in the 

 microcosms tended to be higher than in the bay, but mean values generally fell 



371 



