NUTRIENT BUDGETS IN THE OCEAN 



By 



K. O. Emery/ Wilson L. Orr,- and S. C. Rittenberg^ 



University of Southern California 



INTRODUCTION 



Nitrogen, phosphorus, and silicon are among the most important to 

 living organisms of the more than four dozen elements known to be 

 present in sea water. These elements, the nutrients, together with carbon, 

 hydrogen, oxygen, and minor quantities of other elements, are required 

 for development and growth of plants, which in turn serve as the food 

 base for all animal life. Because of their biological significance, nitrogen, 

 phosphorus, and silicon have been examined more thoroughly than most 

 of the other elements ; yet there remain large uncertainties in the quan- 

 titative measures of their distribution and utilization. 



The general cycle of nutrients involves their introduction into the 

 ocean by rivers and rain, their conversion into organic matter by plants, 

 their partial regeneration in the water, their loss to the sediments by 

 deposition, plus some return to the land and atmosphere by various 

 mechanisms. If steady state conditions exist in the ocean, the annual 

 loss of nutrients must be balanced by addition of new supplies; other- 

 wise, the concentration in the water would increase or decrease, eventu- 

 ally leading to greater or lesser abundance of life. Construction of a 

 budget involves chemical, biological, and geological information having 



^Geology Department. 



^Chemistry Section, Allan Hancock Foundation. 



^Bacteriology Department. 



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