4. Production of the Zoobenthos . 

 (A. N. Golikov, 0. A. Skarlato) 



Estimation of the production of the macrozoobenthos involves a 

 number of methodologic difficulties. It is very difficult to obtain 

 reliable information on the quantitative distribution of organisms of 

 the benthos. On hard bottoms and in stands of underwater vegetation, 

 determination of the quantity of organisms using the standard equipment 

 for quantitative measurement (trawls, drags, bottom diggers) yields 

 results which are low by tens or even hundreds of times (Barnes, 1962; 

 Skarlato et al., 1964), while in soft bottoms the results of the use of 

 these devices will still be low by several times. The significant error 

 in information obtained by standard quantitative benthos-counting 

 devices from ships in comparison to the actual picture has even led to 

 the use of the term "bottom-digger benthos". More reliable data on the 

 quantitative distribution of the benthos can be achieved by quantitative 

 methods of hydrobiologic research using divers (Golikov, Scarlato, 1965; 

 Golikov, Scarlato, 1967). This method is based on direct counting of 

 organisms in homogeneous areas of biotopes covering areas varying from 

 100 m down to 20 cm^, depending on the dimensions of the organisms in 

 question and the nature of their distribution. Organisms are counted in 

 areas, the dimensions of which vary on a logarithmic scale (100, 10, 1, 

 0.1 nr-, etc.) corresponding to the logarithmic distribution of organisms 

 in biocenoses. The selection of sectors for sampling is performed by 

 research divers, who directly (visually) estimate the degree of 

 homogeneity of biotopes, the boundaries of biocenoses, the abundance and 

 variety of life. This makes the quantitative method using divers 

 relatively reliable and accurate as a method of studying the marine 

 benthos in the upper levels of the shelf, down to depths of 30-40 m. At 

 greater depths, in parallel with the use of trawls and bottom diggers, 

 it is desirable to utilize underwater photography and television. 



To determine the production and bioenergetics of biocenoses, one 

 must study the production of the specific populations in these 

 biocenoses. Obviously, reliable determination of production is 

 impossible without knowledge of the peculiarities of growth and duration 

 of life of the animals of a given biocenosis. Most significant for the 

 determination of the production properties of populations is the study 

 of the growth rate and duration of life not of individuals, but of the 

 majority of individuals in a population. However, reliable 

 determination of the age of individuals is usually possible only by 

 means of cumbersome observations in cages. 



The general regularities of growth of poykilothermic aquatic 

 animals and methods of its determination are well known (Vinberg, 1968; 

 Vilenkin, Vilenkina, 1973; Alimov, Golikov, 1974; and others); we shall 

 discuss only 1 method of estimating the group growth of macrobenthic 

 animals. 



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