RESULTS 



Water Column Profiles 



As expected there were three particle maxima in Jordan Basin 

 and two at the Mt. Desert Island station (Fig. 2) . The BNL at 

 both locations was quite pronounced, although it was thicker at 

 the Jordan Basin station. The position of the intermediate 

 particle maximum in Jordan Basin shifted between the two sampling 

 dates. Since it is usually found at the interface between Maine 

 Intermediate and Bottom Water (identified by a change in 

 salinity; Townsend and Cammen, 1985), it suggests major water 

 movements could have occurred between the two sampling dates. 



Samples for total protein concentration were collected 

 during a number of casts in Jordan Basin, but since there were no 

 obvious differences between the dates or the two sampling 

 methods, the data have been combined in one profile (Fig. 3) . 

 Protein concentrations were elevated in all three particle 

 maxima. The samples from the mid-water maximum were collected 

 deliberately at the depth of minimum light transmission. In 

 contrast at the Mt. Desert Island station, total protein 

 concentrations may only be elevated in the surface layer. 



The chlorophyll profiles (Fig. 3) at Jordan Basin were quite 

 different from the protein profiles. There was a clear 

 difference between the two sampling dates with generally higher 

 chlorophyll concentrations on the second date. A major storm had 

 occurred on September 16, just prior to the first sampling date, 

 which may have eroded the nutracline, resulting in a fall bloom 

 by the second sampling date. However, there is no way from the 

 available data to distinguish between that and differences due to 

 horizontal patchiness and water movements alluded to above. 

 There was no evidence of elevated chlorophyll concentrations in 

 the intermediate particle maximum, although there were higher 

 concentrations in the BNL by the second date. At the Mt. Desert 

 Island station, chlorophyll levels were high at the surface and 

 possibly in the BNL. 



The only other data for which there were complete profiles 

 are the nanoplankton (Fig. 4) because their abundance can be 

 determined from small water volumes. In Jordan Basin the numbers 

 of autotrophic nanoplankton were much higher at the surface, 

 generally higher on the second sampling date, and possible 

 elevated in the BNL on the second sampling date. On the other 

 hand, the heterotrophic nanoplankton were more evenly distributed 

 with depth. At the Mt. Desert Island station there was a peak in 

 nanoplankton abundance above the BNL. 



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