THE SEA OF AZOV 469 



sea-level reaches 4-44 m in the Gulf of Taganrog. The picture of the currents 

 is therefore confused. However, it may be concluded that waters are carried 

 out of the Gulf into the Sea mainly along the northern shore, while Azov 

 waters enter it along the southern one. This can be clearly seen from the 

 distribution of the isohalines (Fig. 223a, b) which also give a general picture 

 of the range of salinity in the Gulf of Taganrog. 



The water-balance of the Sea of Azov is made up of the elements given in 

 Table 193 (V. Samoilenko, 1947). 



Table 193 



Influx km 3 Consumption km 3 



River discharge 41 Evaporation 29 



Precipitation 14 Loss through the Kerch 



Inflow through the Kerch Strait 8 8 to 1 2 1 



Strait 63 to 96 Loss through the Narrow 



Inflow through the Narrow Strait (into the Sivash) 4 



Strait (out of the 3 



Sivash) 



Total 121 to 154 Total 121 to 154 



Since the inflow of fresh water into the Sea of Azov is not fully matched by 

 evaporation, the remaining surplus of water is distributed between the Geni- 

 chensk and Kerch Straits. In early spring a surplus of saline water flows from 

 the Sivash into the Utlyukski inlet through the Genichensk Strait, but for the 

 rest of the year there is a prevailing current from the Sea into the Sivash. The 

 exchange of waters through the Kerch Strait is irregular in character, being 

 greatly affected by winds. The currents of the Kerch Strait play an important 

 part in the hydrology and biology of the Sea of Azov : on the one hand, the 

 surplus masses of less saline waters are carried out of the Sea of Azov by this 

 current ; on the other, the more saline waters of the Black Sea are carried in. 



The Tsymlyansk dam on the river Don was completed in 1952. This led to 

 the formation of the huge Tsymlyansk water reservoir above the dam, while 

 below it new conditions in the river and the Sea began to form (A. Karpe- 

 vitch, 1957). Twenty-three per cent of the average yearly discharge of the Don 

 was intended to be removed for irrigation purposes. In coming years, as a 

 result of hydro-power construction on the rivers Don and Kuban, the supply 

 of nutrient substances into the Sea of Azov will be reduced by about 50 per 

 cent, while the primary production of phytoplankton will decrease to about 

 40 per cent of the annual average (V. Datzko and M. Fedosov, 1955). More- 

 over, the salinity of the Sea of Azov will increase to 15% . In 1952 the salinity 

 of the Sea of Azov increased on the average about 0-4 1% by comparison with 

 1951. In 1953 it increased again by 0-32% o (E. Vinogradova, 1955). 



According to V. P. Vorobieff (1944) the average annual discharge of solid 

 matter from the land into the Sea of Azov is of the order of 8-3 million tons, 

 which gives on the average 12-9 cm 3 per 1 m 3 of water, whereas the discharge 

 of dissolved substances is more than 13 million tons. 



