Sushchenya, 1969, 1972; Shushkina, Vilenkin, 1971; Edwards, 1973). In 

 calculating the production of tropical zooplankton in the euphotic layer 

 from the metabolic rate, the temperature corrections apparently should 

 not be introduced. 



Calculation of the mean daily value of production by the 

 physiologic method presumes knowledge of the mean coefficient of 

 utilization of assimilated food for growth K2 for the population or 

 group of animals studied. As follows from equation (3.1), the value of 



r,8 Z,g 2,2. 2.'^ 2.S 2,8 3,0 3,2 3^ 38 



Log Wg, mcal/indiv. 



Fig. 26. Dependence of the metabolic rates R (meal/day per individual) 

 upon the body weight W (mcal/indiv.) for copepoda at various t, C. 1 • 

 tropical Calanoida at 30°C (Shushkina, Pavlova, 1972); la - same, 

 adjusted to 20°C using temperature correction suggested by L. M. 

 sushchenya (1969); 2 - tropical Calanoida at 20°C (Musaeva, Vitek, 

 1975); 3 - Calanoida at 20°C (Sushchenya, 1969). 



K2 is determined by the ratio of production to assimilated food, i.e., 

 to the sum of production plus the cost of metabolism. Determination of 

 production requires regular observation of the growth of animals, plus 

 knowledge of the regularities and rates of their breeding. Therefore, 

 the volumes of accumulated factual material on the values of K2 for 

 aquatic animals is not sufficient to allow reliable conclusions to be 

 drawn, although a number of works have been published, dedicated to the 

 analysis of the variability of this coefficient (Sushchenya, 1969; 

 Shushkina, Klekovskiy, 1966; Kryuchkova, 1967, Sushchenya, 1970; Ivlewa, 

 1970; Mullin, Brooks, 1970; Soldatova, 1970; Shushkina, 1972; Bougis, 

 1974; Zaika, 1974; Pasternak, 1974; Khmeleva, 1967). The studies which 

 have been performed indicate several conclusions concerning probable 

 changes in maximum and average values of K2 and the influence of 

 environmental factors on this quantity. 



For rapidly growing species and populations under optimal 

 conditions, the value of K2 is near 0.6 (Winberg, 1964, 1973; Klekowski, 

 Shushkina, 1966; Sushchenya, 1970), although during some periods of 

 development (embryonal, older nauplial stages of copepoda, young 

 cladocera, etc.), K2 may be as high as 0.7-0.8 (Winberg, 1956, 1968; 

 Zaika, 1974; Bougis, 1974). Many authors assume that for natural 

 populations of aquatic animals, the mean value of '^o is closer to 0.3- 

 0.4 (Winberg, 1966; 1973; Sushchenya, 1970; Greze, 1971; Shushkina, 



294 



