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



A similar picture of quantitative distribution of benthos (number of speci- 

 mens and biomass) is given by Nikitin for the Anatolian coast. The maximum 

 number of specimens was observed at 60 to 75 m (up to 1,500 specimens/m 2 ), 

 and the greatest biomass at 35 to 50 m (up to 2,000 g/m 2 ). 



The Black Sea is inferior to the Sea of Azov and superior to the Caspian 

 Sea in the benthos biomass of the populated part of its floor. Comparing the 

 benthos of the Black and Azov Seas V. Wodjanitzky (1940) comes to the con- 

 clusion that only about 50 per cent of the benthos of the former can be used 

 by fish (food-benthos), whereas in the Sea of Azov it is almost entirely food- 

 benthos. Hence taking into consideration its feeding properties the Sea of 

 Azov benthos is four times more productive than that of the Black Sea, and 

 when calculated for the whole surface of the Sea it is sixteen times more pro- 

 ductive. 



Quantitative estimate of microbenthos. In 1939-40 L. Arnoldi carried out the 

 first quantitative recording of the microbenthos of the upper layers of the 

 soil (1-5 to 2-5 m) in the northwestern part of the Black Sea. As numbers go, 

 the first place is occupied by worms (nematodes, nemerteans, archianellides) 

 ciliates, crustaceans and mollusc larvae. 



The number of micro-zoobenthos specimens reaches 4-6 million per 1 m 2 

 (on the average 1-6 million) and its biomass 30 g/m 2 . 



The number of micro-phytobenthos (diatoms) reaches 30 to 50 million 

 specimens per 1 m 2 , giving a biomass of up to 10 g/m 2 . 



Summarizing the as yet insufficient data on the numbers of the Black Sea 

 fauna one can draw up Table 187. 



The presence of numerous inlets at all stages of their development (Fig. 216) 

 is the characteristic peculiarity of the northwestern part of the Black Sea. 

 N. Zagorovsky (1925-30), F. Mordukhai-Boltovskoy (1948, 1953) and Yu. 

 Markovsky (1955, 1959) have studied the inlets. A description of the Bulgarian 

 inlets is given by G. Paspalev, A. Volkanov and G. Caspers, and of the Ruman- 

 ian ones by P. Bujor. 



The Dniester, Sukhoy, Khadzhibeysky, Kuyal'nitsky, Greater and Lesser 

 Adzhalitsky, Tiligulsky, Tuzlovsky solonetz, Berezansky and the Dnieper- 

 Bug inlets (Fig. 216) are river valleys flooded (possibly several times) 

 by the post-Pliocene sea when its level was much higher than at present. 

 In the later, drier periods, when river waters were not abundant, the inlets 



