476 



BIOLOGY OF THE SEAS OF THE U.S.S.R. 



Fig. 225a. Diagram of distribution of soils in Sea of Azov 

 (Vorobieff, 1949). 1 Ooze-shell gravel ; 2 Clayish ooze ; 3 Shell 

 gravel on sand-ooze and ooze-sand. 



The distribution of organic carbon in the upper layer of the sea-bed soils 

 corresponds closely with the change in the nature of the latter (T. Gorshkova, 

 1955). It is most remarkable that no special accumulation of organic carbon 

 is observed anywhere in the Sea of Azov, not even in its deep central part, as 



Fig. 225b. Distribution of organic carbon, expressed as percentage of dry weight of 

 the substance in the upper layer of the Sea of Azov deposits (Gorshkova, 1955). 

 1 From 2-9 to 2-4%; 2 From 2-4 to 20%; i From 20 to 1-5%; 4 From 1-5 to 1%; 



5 From 1 to 0-5%. 





