Fig. 11. Diagram of trophic zonality over a broad, flat shelf under 

 eutrophic (a) and oligotrophia (b) conditions. Zone of dominance of 1, 

 Sestonophages; 2, Gatherers; 3, Swallowing detritophages. Not drawn to 

 scale. 



regional ization of the shelves, we can also abstract ourselves from 

 vertical zonality. The influence of the productive properties of the 

 shelf waters on the characteristics of the bottom population remains to 

 be studied. 



The first attempt to analyze the trophic structure of the benthos 

 on the example of the shelves of the eastern portion of the Bering Sea 

 and the East China Sea (Neyman, 1969b) led to the conclusion of the 

 decisive influence of the productivity of the waters on the trophic 

 structure of the benthos. Both of these shelves are broad, flat 

 shelves, with a well -developed zone of sedimentation in their central 

 portion. The benthos of the East Bering Sea shelf has a clearly 

 expressed eutrophic structure, corresponding fully to the high 

 productivity of the overlying water. The trophic zonality clearly 

 corresponds to the morphology of the shelf (see Fig. 10a); represen- 

 tatives of all trophic groups have practically 100% occurrence. On the 

 shelf of the East China Sea, over broad areas beneath the low- 

 productivity Kuroshio waters, swallowing detritophages are scarce or 

 absent (Fig. 12), while gatherers are not represented at all stations, 

 the zone of predominance of the leading group (<50%); over a large area, 

 a zone of dominance of sestonophages is found. If we base our judgments 

 on the distribution of benthic deposits, we would expect the development 

 of three trophic zones and their distribution according to a type 

 typical for broad, flat shelves. Thus, on the shelf of the East China 

 Sea, there is disruption of the trophic zonality, manifested as weak 

 development of the zone of gatherers and total absence of the zone of 

 swallowers over large areas of the shelf. All of this fits the 

 definition of an oligotrophia structure according to M. N. Sokolova. 



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