THE BARENTS SEA 



139 



adjacent to Finmark. Porifera and Brachiopoda are predominant in these 

 regions. 



The third region of greatly increased epifauna biomass lies on the south- 

 eastern slopes of the Spitsbergen shallow. The patch of increased biomass in 

 the north of the Barents Sea, southwest from Franz Joseph Land, corresponds 

 to a considerable rise of the bottom, and likewise consists mostly of epifauna. 

 In the central part of the Barents Sea considerable quantities of epifauna 

 extend in a wide meridional band along 37° and 38°, on the shallow crest 

 which separates the western depth of the Sea from its central depressions 



Fig. 53. Quantitative distribution in Barents Sea: A Bivalves (full line) and 



polychaetes (dotted line); В Echinoderms. Thicker lines denote greater biomass 



(Brotzkaya and Zenkevitch, 1939). 



passing at the north into the central shallow. In the east an abundant epi- 

 fauna thrives north of Kolguev Island and especially on the Gusinaya bank 

 and farther along the shallows ofTNovaya Zemlya. In these regions the echino- 

 derms are preponderant (Strongylocentrotus, Ophiopholis, Psolus) and some 

 molluscs (Saxicava, Pecten, Buccinidae), crustaceans (Balanus and Eupagurus) 

 and polychaetes (Thelepus). The biomass of the central depression with its 

 great depths is comparatively poor. Coarse sand and gravel floors are very 

 poorly populated. They are practically without life. Such regions are found in 

 the Voronka of the White Sea southwest of Kanin Nos. 



The main groups of the benthos — echinoderms, bivalves, polychaetes and 

 sipunculids — play different roles in furnishing the common biomass in 

 different areas of the sea (Fig. 53). 



Lamellibranchiata are adapted mainly to fairly shallow (<150 m) silty- 

 sand bottoms with a large detritus content. The largest accumulations of bi- 

 valves are found off the coast of Novaya Zemlya, in the Pechora region and, 

 mainly, between Kolguev Island and Novaya Zemlya where their biomass 



