In Japan, nuclear electric power plants alone will consume 130,000 

 m-^ of sea water permitted for cooling purposes by 1980 (Niva, 1973). 



The Hunterstone nuclear power plant (in Scotland) dumps 91,000 m-^ 

 of water with a temperature of water 8-10°C higher than the natural 

 water into the Firth of Clyde each hour. As a result, the surface 

 temperature in the region of this thermal pollution is increased by 3- 

 5°C (Barnett, 1971, 1972). 



Usually, the temperature of water dumped by electric power plants 

 and industrial enterprises is 5 to 13°C higher than the temperature of 

 the natural waters, and in some cases it has been heated by as much as 

 14-24°C. 



Regular thermal pollution changes the annual course of temperature 

 of natural waters. For example, at Marchwood on the south coast of 

 England, before construction of the thermal electric power plant in the 

 mid-1950' s, the minimum temperature of the surface water (February) was 

 1-2°C (in 1954, the temperature dropped to -1°C) while the maximum (in 

 August) was 22°C; after the power plant went on stream, the temperature 

 never dropped below 6.5°C in winter and in summer it rose to 26.5-27°C 

 (Raymont, Carrie, 1964). 



In Copenhagen Harbor, the water temperature near the area of 

 thermal pollution of one factory reached 6°C even in winter, while in 

 Southhampton Harbor, 400 m from the thermal dump of an electric power 

 plant, it was 3°C higher than the natural temperature, and in the 

 discharge canals of electric power plants in the Patuxent River estuary 

 (Chesapeake Bay) it was 6.3°C higher, and in Biscayne Bay (Florida)--5''C 

 higher than the temperature of the natural water receiving the thermal 

 discharge (Naylor, 1965b; Nauman, Cory, 1969; Thornhaug et al . , 1973). 



3.2 Influence of Thermal Pollution on the Conditions of Existence 

 of Flora and Fauna 



The dumping of heated waters into the sea leads to an increase in 

 the temperature of the natural waters of the region, a decrease in their 

 oxygen content, a decrease in viscosity, a shift of the hydrologic 

 seasons in the surface layers (abnormal lengthening of the hydrologic 

 summer). These changes, in turn, lead to changes in the nature of 

 circulation of water in bays and estuaries, stagnation of water, and 

 increase in the rate of sediment formation and silting, particularly in 

 the sunrmer. 



The effect of thermal pollution on the aquatic communities of the 

 estuaries, bays and other marine coastal areas can be quite varied in 

 form, being direct and indirect, ranging from very strong to weak. 

 Heating of natural waters by 4-6°C (and in the summer, sometimes, by 

 only l°C--Bush et al . , 1974) may result in the death of a number of 

 stenothermal species, suppression of the breeding of many species, 

 changes in the specific composition of communities due to replacement of 

 local species with thermophilic intruders, changes in many biologic 

 characteristics of local species--metabolism, shape formation of 

 colonial animals, behavior, nutrition, etc. This heating may lead to a 



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