2. No examples of oligotrophic structure of shelves with weak 

 hydrodynamics have been found. 



3. On shelves with spatially heterogeneous dynamics of the bottom 

 waters and eutrophic conditions in the zone of sediment accumulation, 

 zones of predominance of detritophages, swal lowers and gatherers are 

 formed. Under oligotrophic conditions, detritophages are weakly 

 developed: In large areas of the bottom they are absent, particularly 

 swallowers. The zone of predominance of swallowers is not expressed, 

 the zone of predominance of gatherers is weakly expressed; throughout 

 almost the entire shelf area, sestonophages predominate. Thus, the 

 disruption of the trophic zonal ity characteristic of the oligotrophic 

 abyssal zone is seen on the shelves only under conditions of spatial 

 heterogeneity of the dynamics of the bottom waters. 



The method of separating trophic groupings on the basis of the 

 source of food has allowed us to approach an interpretation of the 

 connection between the benthic population and the nature of distribution 

 and type of transformation of organic matter, i.e., between the fauna of 

 the benthos and the biogeochemical processes. It has been found that a 

 similar type of transformation of organic matter causes similar 

 development and relationship of trophic groupings under conditions quite 

 different with respect to other characteristics (L. G. Vinogradov, 1963, 

 1966; Vinogradov, Neyman, 1965). Due to the precise and unambiguous 

 connection with the conditions of sediment accumulation, trophic zones 

 and sets of zones are structural units for the description of planetary 

 regularities of the distribution of the benthic population. 



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