The regularities outlined above concerning the composition and 

 distribution of benthic biocenoses were obtained upon detailed study of 

 benthic biocenoses on the shelves of arctic and boreal waters. 

 Analogous data concerning the shelves of Antarctic waters are sparse. 

 However, on the shelf and in the fjords of the south Orkney Islands, 

 basically the same composition of biocenoses and the same variation of 

 their distribution with the nature of the benthos of the tropical 

 shelves differs from that of the subpolar shelves in that there are 

 significant sections where the trophic zonal ity is disrupted or where 

 the detritophages, particularly swallowing detritophages, disappear from 

 the composition of the benthos. The same differences have also been 

 noted in the composition of biocenoses. Whereas in the shelf biocenoses 

 of the subpolar waters, all trophic grouping of nonpredaceous benthic 

 invertebrates are practically always represented, in the shelf 

 biocenoses of the subtropical and tropical waters, usually only one or 

 two trophic groupings are present. 



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