68 



REDFIELD, KETCHUM AND RICHARDS 



[CHAP. 2 



the value of R, the rate of change of any of the nonconservative properties, may be ob- 

 tained for any unit volume directly from equation (la). The average values obtained for 

 the rate of change in oxygen concentration and of phosphorus regeneration at depth are 

 shown in Table XI. 



Table XI 



Average Eddy-Diffusion Coefficients and Rates of Change in Oxygen and Phos]ihate 

 Concentration, as Estimated by Riley (1951) 



The procedure is not well adapted to the analysis of the deep water because of the small 

 gradients present. The results obtained for water below 1500 m are presented by Riley 

 with some reserve. The values entered in Table XI indicate merely the magnitude of the 

 items. Also, it was found impractical to deal with the surface layer by these procedures. 



The description of the physical circulation obtained by the analysis of the 

 mathematical model agrees in general with that obtained by other methods. 

 As a check on its utility in accounting for the distribution of nonconservative 

 elements, the results obtained were used to reconstruct the distribution of 

 hosphate and nitrate in a north-south section of the Atlantic basin. The 

 istribution obtained for phosphate is shown in Fig. 16. The distribution 

 estimated from the dynamic balance of the factors evaluated from the model 

 agree in all essential details with that observed in nature. 



The estimates of oxygen consumption and phosphate regeneration provide a 

 means of determining the oxidative ratio, AOjAV, discussed on page 32. The 

 atomic ratio obtained for the water column as a whole, from 200 m to the 

 bottom, is — 255. This value differs by only 8% from the theoretical ratio of 

 — 276 obtained from the analysis of plankton. When the values obtained from 

 the several at surfaces are examined, the ratios vary widely and are nearly four 

 times greater than the theoretical ratio in the water of the intermediate layer 

 (see Table XI). 



