high hydrostatic pressures. These might include interfacial tension of 

 small bubbles on solid surfaces, or surface active films under high 

 compression at the bubble-solution interface. 



Progress has been made in characterizing the size distribution of bubble 

 populations in the surface layers of the ocean (Medwin, 1970). This 

 effort should continue to be pursued, along with chemical characteriza- 

 tion of the bubbles. Classical studies of the stability and dissolution of 

 bubbles in seawater (Wyman et al., 1952; Liebermann, 1957) should 

 be extended, where possible, to smaller bubbles and to include con- 

 sideration of their behavior in the presence of surface active substances 

 and solid surfaces. 



Air-Sea Interface 



In recent years there has been intensive consideration of chemical 

 processes that occur at the air-sea interface. Some of these processes 

 can be related to bubbles and the mechanisms by which they burst 

 through the interface, producing chemical fractionation in the droplets 

 injected into the atmosphere (Bloch and Luecke, 1972; and Maclntyre, 

 1972). However, there also appear to be other unique chemical char- 

 acteristics of the air-sea interface that affect the minor elements of 

 seawater. Duce et al. (1972) demonstrated the near-surface enrichment 

 of such components as iron, lead, copper, and fatty acids. The specific 

 processes involved in this enrichment have not been clearly estabhshed, 

 although it is assumed that minor element association with surface 

 active organic material is a significant factor. These mechanisms should 

 be determined and the chemical stability of surface active materials 

 on the sea surface must be examined. Factors to be considered are the 

 breakdown of surface active materials by wave action, or chemically, 

 photochemically, or by biochemical oxidation. 



Examination of near-surface gradients of phosphate (Goering and 

 Wallen, 1967) and of others that undoubtedly occur for other minor 

 constituents may provide significant clues about the processes occurring 

 near the air-sea interface. 



Analytical Studies 



Historically, the direction of effort to investigate an important chemical 

 process has been dependent to a great extent on the availability of a 

 useful analytical method. The solution of analytical problems continues 

 to be of crucial importance (Carpenter, 1972) in the study of trace- 

 element chemistry of the marine environment. It is necessary to have 



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