of a population, it is important to have material covering most of the 

 ecologic zones inhabited by the species in the given location. This 

 allows us to consider individuals of different ontogenetic stages in the 

 population, frequently restricted to different biotopes. One simple 

 method of estimating the spatial heterogeneity of the dimensional 

 structure of a population is to compare the frequency of occurrence of 

 individuals of a given size in different sinusia (levels) of the 

 biotopes and at different depths. 



The relationship between dimensional and weight characteristics of 

 individuals of a population is not difficult to estimate using the 

 equation W = aL , where W is the weight of an individual and L is its 

 maximum linear dimension. Studies of recent years (Alimov, Golikov, 

 1974; Tsvetkova, 1974; and others) have shown that the values of 

 coefficients a and b in representatives of a single life form do not 

 differ statistically. This greatly facilitates estimation of the 

 parameters of the equations for various species. The weight of 

 organisms of a single length (coefficient a) is determined by the shape 

 of the body and the specific weight of the organisms, while the 

 regression coefficient b is determined by the degree of allometry of 

 growth. In calculations of production, it is desirable to use the wet 

 mass. 



In determining the production of the zoobenthos, most authors use 

 various modifications of the Boysen-Jensen method (Boysen-Jensen, 1919), 

 based on estimation of the total weight increase of individuals 

 remaining in the composition of the population over the period of 

 observation and the main weight of individuals eliminated during that 

 time. In the simplest case, the annual production of a population is 

 calculated by the equation: P = Bx + B^, B^- and B^+i are the 

 biomass of a population at the beginning and end of the year analyzed, 

 Bg is the biomass of individuals eliminated during the year, estimated 

 as the difference between the initial and final populations, multiplied 

 by the mean weight of individuals eliminated: 



This method, sometimes with slight variations, is widely used in the 

 literature to calculate the production of massive species of zoobenthos 

 (Boysen-Jensen, 1919; Blegvad, 1928; V. V. Kuznetsov, 1941, 1948a-c; 

 Vorob'yev, 1949; Shorygin, 1952; Sushchenya, 1967; Masse, 1968; 

 Khmeleva, 1973; and others). It is usually used for littoral regions, 

 located near marine biologic institutions, since determination of 

 production by this method requires repeated frequent sampling of 

 materials from the same biocenoses. In the improved Boysen-Jensen 

 method (Bekman et al., 1968; Winberg et al . , 1971; and others), 

 production is calculated by the equation: 



P = I 7 (Nt + Nx+l) (Wt+1 - Wt) "Sf . (4.2) 



T=0 



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