The Distribution of Major Organic Nutrients 211 



It can be seen that wide variations exist (both in absolute 

 values and in ratios ) within single cores as well as between cores 

 in the same or different environments. For reference, Table 4 also 

 shows the same kind of analysis on a common medium often 

 used for studies of marine organisms, Medium 2216 E of ZoBell 

 (9). 



ACKNOWLEDGMENTS 



Cores from the Gulf of California were provided by Dr. Tj. 

 H. van Andel of Scripps Institution of Oceanography. Those 

 from the Cariaco Trench were sampled at Woods Hole Oceano- 

 graphic Institution througli the courtesy of Dr. J. M. Zeigler. The 

 Norwegian samples were obtained while the author was a guest 

 member of the scientific party aboard WHOI R/V Chain cruise 

 No. 13, Dr. J. B. Hersey, chief scientist. 



Technical assistance during these investigations was pro- 

 vided by Mrs. Marcia D. Lupton, Dr. C. V. Campbell, Mr. K. 

 V. Davis, and various members of the scientific part}' and crew 

 of R/V Chain. 



SUMMARY 



A wide variation in the local concentrations of the major 

 biochemical fractions (proteins, carbohydrates, and ether-ex- 

 tractable lipids) exists within different marine sediments. This 

 variation is in ratios of the three fractions as well as in absolute 

 amounts. 



Interesting trends of protein and carbohydrate decrease and 

 lipid increase have been observed in deeper sediments from some 

 areas. Further research is needed to clarify the mechanisms con- 

 cerned, and to determine whether microbial reactions are in- 

 volved. 



An implication of these results is that some previous studies 

 of the activity of marine sediment microbes may have involved 

 use of "overfed" or "nutritionalK^ unbalanced" cultures. Further 

 work in this field should consider nutrient \e\eh of primary im- 

 portance in design of experiments in which attempts are made 

 to duplicate a natural environment. 



REFERENCES 



1. FoLiN, O. and Malmros, H.: An improved form of Folin's micromethod 

 for blood sugar determinations, /. Biol. Chem., 83:115-120. 1929. 



