THE SEA OF JAPAN 



767 



A predominance of perennial forms, with an all-year-round growth, is 

 characteristic of the northern part of the Primor'e (T. Shchapova, 1956). They 

 comprise two species of Fucus and Pelvetia babingtonii which, with a biomass 

 of the order of 5 to 7 kg/m 3 , form continuous homogeneous belts. 'The 

 littoral of the northern Primor'e', writes Shchapova, 'is similar in the 



Fig. 380. Cross section through littoral of Olga 

 Inlet off Cape Linden. 1 Pelvetia wrightii f. 

 babingtonii; 2 Gloiopeltis capillaris; 3 Nemalion 

 helmintoides ; 4 Rhodomela latix; 5 Cora/Una 

 pillulifera ; 6 Plant mozaic ; 7 Iridea sp. ; 8 Chon- 

 drus pinnulatus; 9 Sargassum sp.; 11 Phyllo- 

 spadix scouleri; 11 Costaria costata. Biomass in 

 g/m 2 (Shchapova). 



development and thickness of its fucoid cover to the littoral of the northern 

 Atlantic, the Murman coast and the White Sea.' 



As a result of unfavourable winter conditions in the northern Primor'e 

 'bottom vegetation is absent from the upper half of its littoral; the fucoids 

 frequently sink below zero depth (displacing the fringe of red algae) and there 

 is a general lowering of all the zones'. The formation of a layer of red algae 

 Gloiopeltis above the belts of Fucus and Pelevetia is very characteristic of the 

 Sea of Japan (and of the Bering and Okhotsk Seas). In the upper horizon of 

 the sublittoral brown algae, at times forming large beds, are mixed with the 

 sea-weeds of a northern aspect such as the fucoids, Myelophucus intestinalis 

 and Stictyosiphon tortilis. This mixture of northern and southern elements in 



