Marine Bacteriology and the Problem of Mineralization 53 



of burial in the sediments indicated tliat a maximum of al)out 

 8.6 X 10^ metric tons per year could be denitrified annually 

 in such areas which is only 10 per cent of that needed to balance 

 the budget. Three possible answers to the dilemma were consid- 

 ered: 1) the data used for calculating the budget were grossly 

 in error, 2) anaerobic microenvironments exist in the water col- 

 umn, as for example within the test of a decomposing planktonic 

 organism or 3) bacteria exist which denitrify in the presence of 

 oxygen. Although the last alternatixe might not appeal to the 

 modern bacterial biochemist, in light of the data then available, 

 the search for such bacteria would have made sense to marine 

 microbiology. 



TABLE 1 

 Nutrient Budget of The Oceans* 



That faulty data are not completely responsible for the lack 

 of a balance is suggested by a recent contributition by Erickson 

 ( 8 ) . Using a different approacli to calculate nitrogen balance, he 

 arrived at a value of 10^ metric tons per year for the magnitude 

 of denitrification, essentially the same as the previously mentioned 

 value. Searching for the site of this process, he suggested the 

 possibility that "there are organisms that can carry out denitrifi- 

 cation inside their bodies. It may be possible that at least in 

 some species denitrification occurs as a by-product in the normal 

 reduction of nitrate to ammonia which has to be carried out in 

 the assimilation of nitrate by plants." Again, although such an ex- 

 planation might be classified as heresy by the modern bacterial 



