HYDROGRAPHY OF THE MARINE WATERS 



37 



Fig. 15. Surface distribution of salinity in Pamlico Sound, January, 1927. Chart prepared by 

 H. R. Seiwell and published here through the courtesy of the U. S. Fish & Wildlife Service. 



On the other hand, in shallow waters such as in sounds or over the continental 

 shelf, the limited depth checks this loss, and turbulence and up welling 

 replenish the supply. In addition, such shallow waters are usually so located 

 as to be replenished with nutrients carried by the rivers from adjacent land. 

 Little is known as to the availability of such limiting nutrients or of hydro- 

 graphic features that might add nutrients to the continental shelf off North 

 Carolina. Upwelling is not known to occur, and additions through the river 

 discharge, discussed below, are not great. As suggested in the section above 

 on Temperatures Offshore, winds, currents, and physiographic features may 

 cause considerable turbulence in the Hatteras region. Land drainage may 

 prove important in contributing nutrients and it may be that a counter- 

 clockwise circulation (see the section above on Circulation Offshore) aug- 

 ments this by directing southward the discharge from Chesapeake Bay. 



