Fiq. 17. Larqe-scale trophic <iines of 

 deep-water macrobenthos. 1, Latitudinal 

 eiitrophic zones; 2, Latitudinal 

 oliqotrophic zones; 3, Periconti nental 

 eutrophic zone. 



large relief forms, as the sedimentation conditions change with depth, 

 regular alternation of zones of predominance of deposit- and suspension- 

 feeders is observed, i.e., vertical trophic zonality in the distribution 

 of feeding groups. In the deep-water macrobenthos, this zonality is 

 most clearly seen on the slopes of the continents and trenches. The 

 zones of deposit-feeders here are much larger and more regular than the 

 zones of suspension-feeders. With the transition from the slopes to the 

 bottom of the trenches, the vertical trophic zonality, under the 

 influence of relief, is replaced by a patchy distribution of feeding 

 groups (Sokolova, 1960, 1964, 1969). 



The global trophic zonality of distribution of deep-water 

 macrobenthos is determined by the distribution of the main productive 

 zones in the ocean. Two types of zonality are distinguished: 

 latitudinal (climatic) and ci rcumcontinental . The combination of these 

 two types of zonality defines the existence of eutrophic and 

 oligotrophic regions on the ocean floor (see Fig. 13). The latitudinal 

 trophic zonality of the deep-water macrobenthos consists in an 

 alternation of gigantic zones of predominance of detritophagous 

 invertebrates and sestonophagous invertebrates from north to south (Fig. 

 17). These zones agree approximately with the climatic zones of 

 sedimentogenesis in the ocean (Lisitsyn, 1974). The two temperate, and 

 humid equatorial zones of sedimentogenesis generally correspond to the 

 eutrophic zones of deposit-feeders, the two arid zones--to the northern 

 and southern oligotrophic zones of suspension-feeders. 



The ci rcumcontinental zonality of distribution of feeding groups of 

 the deep-water macrobenthos consists in the existence of large-scale 

 eutrophic zones of predominance of deposit-feeders in the 



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