need to be studied both in areas where we expect rapid turnover (inter- 

 faces between sea and air, seawater and fresh water, seawater and 

 sediments, and water and particulates) and in areas of low reactivity, 

 such as the deep sea, where waste materials may persist indefinitely. 



Organic compounds in the sea interact with other components of the 

 ocean in ways that require, in most cases, further study. Thus, certain 

 organic compounds play a role in the speciation of inorganic ions and 

 determine their availability; other compounds may mediate processes 

 that affect the life cycles of organisms (chemotaxis). Therefore, marine 

 organic chemistry relates directly to oceanic productivity and to the 

 capability of the ocean to recover from perturbations. 



The great complexity of the marine organic matter presents an analyti- 

 cal challenge. Much development is needed to insure clean sampling, 

 sample preservation, and initial separation of the concentrates into 

 type compounds. For some classes of compounds (e.g., lipids, amino 

 acids, carbohydrates), adequate analytical techniques are available 

 from related fields. In other areas (e.g., marine polymers such as humates, 

 fulvates, alginates, metal complexes) progress still depends on the 

 development of methods for rapid routine analysis during large-scale 

 oceanographic studies. 



Table 5 classifies the sites of organic matter in the sea; it states some 

 basic questions and suggests research areas and applications that deal 

 with the impact of life processes on the organic chemistry of the ocean. 



LIFE PROCESSES AND NUTRIENT SUBSTANCES 



Life processes in the ocean alter the composition of seawater, and 

 the changes thus produced impart distinguishing characteristics to the 

 water in which they take place. The perturbation of the chemical medium 

 may be apparent and easily detectable by chemical means, or it may be 

 subtle, but nonetheless biologically significant in a long or short time 

 scale. The former kinds of changes have made possible one of the classi- 

 cal activities of chemical oceanography — the characterization and tracing 

 of water masses in the ocean. Continued research in this field appears to 

 be essential, not simply to improve our knowledge of fields of motion in 

 the ocean, but to predict the effects of biologically induced chemical 

 changes on processes (chemical, biological, physical, geological) down- 

 stream from the sites of the biological events. Among questions to be 

 resolved are prediction of plankton blooms as the result of nutrient 

 fertilization, the detoxification of metals by chelation, and the stimula- 

 tion of growth processes by the injection of vitamins and other bio- 

 chemically active substances into a water mass. The changes brought 

 about by life processes on the chemistry of the ocean are important for 



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