The production of a population includes both the weight of 

 individuals which have disappeared from the population during the 

 calculated time due to natural death, consumption or migration, as well 

 as the weight gain of individuals remaining in the population at the end 

 of the period in question. Whereas the first portion of the production 

 process represents a sort of reserve of strength of the population, the 

 second portion is important in principle for its very existence. To 

 symbolize this second portion of production, which represents the 

 quantity of living matter formed during the time of turnover of a 

 generation (in this case--during a year) and remaining in the 

 population, the concept of supporting production has been developed 

 (Golikov, 1970). The supporting production P^ is responsible for the 

 creation of that portion of the biomass of a population which is formed 

 during the turnover of 1 generation. For species with a duration of 

 life of individuals of more than 1 year, the supporting production is 

 expressed as the sum of the biomass of juveniles (of the same year) and 

 the annual weight increase of the individuals of older generations 

 present at the beginning of the year. 



n 



= I Nx(W, - W,.i) 4 . (4.8) 



T = 



At 



where W^ and Wx-i are the weight increase of individuals of the 

 generation in question, which survive and remain in the composition of 

 the population over the time interval analyzed (in this version--! 

 year). This same equation, with the corresponding time correction At, 

 is apparently suitable for estimation of the supporting production of 

 populations of species with durations of life of individuals of less 

 than 1 year. 



It is significant that the production process during the course of 

 the time analyzed occurs in all generations of the population 

 simultaneously, which allows us to generate an integral expression for 

 the full growth production of the population and its supporting 

 component during the same time interval. The supporting portion of 

 production during the year preceding the time of observation, given 

 reliable data on the quantitative structure of the population and growth 

 of individuals, can be determined rather accurately using a single 

 sample, regardless of the degree of steadiness of the population, since 

 it reflects the weight increase of the surviving individuals of each 

 generation only. 



If it is possible to perform several observations, the mean annual 

 supporting production can be determined using an equation analogous to 

 equation (4-5) 



n 



^ Psn 

 P -_ '-'\ . (4.9) 



^m n 



The supporting portion of the production process, not including the 

 living matter which has disappeared from the composition of the 



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