In recent decades, research vessels have made thousands of voyages 

 to all regions of the World Ocean; hundreds of thousands of fishing 

 ships are at work each day, catching fish down to depths as great as 

 2,000 m, at all distances from their bases, using the most modern 

 equipment available for the detection and catching of commercial 

 varieties of fish. As a result, an extensive fund of data has been 

 accumulated concerning the topography of the bottom of the World Ocean, 

 the oceanographic characteristics of its various regions, and the 

 regularities of the processes which define the biologic productivity of 

 the ocean. They allow us to form an approximate idea of the volume of 

 commercial production formed each day in the World Ocean and the 

 peculiarities of its distribution and reproduction. 



1.1 Productive Regions of the Ocean . 



The biologic productivity of the World Ocean and, in the final 

 analysis, the volume and nature of its commercial production, depend to 

 a great extent on the relief, hydrological and hydrochemical regimes, 

 atmospheric processes, balance of nutrients, and on the peculiarities of 

 the productivity of phytoplankton and zooplankton. We should emphasize 

 a few facts which are of particular significance for an understanding of 

 the peculiarities of the production and distribution of the biological 

 resources of the World Ocean. 



Only 7.4% of the area of the ocean is less than 200 m deep, only 

 11.4% is less than 1,000 m deep. Almost 77% of the area of the ocean is 

 over 3,000 m deep (Table 2). If we consider that the most extensive 

 shallow-water areas are located in the Arctic, with a great deal more in 

 the Antarctic, we find that the total area of regions favorable for 

 habitation by commercial benthic animals is about 30 million km^--only 

 8% of the area of the ocean. However, it is the continental shelf and 

 the waters of the peripheral regions of the ocean which are most 

 productive and it is this area, 20% of the water area of the ocean, 

 which acounts for some 90% of the present world catch. This uneven 

 distribution of the catch is primarily a result of the fact that areas 

 of high biologic productivity are to be found around the edges of the 

 oceans. 



It has been established in recent years that a significant quantity 

 of fish, in accumulations dense enough to allow successful commercial 

 fishing, may be formed in individual areas of the World Ocean far from 

 the coast, near the slope or over elevated areas of the deep-sea floor 

 (with depths as great as 2,000 m) . This type of concentration results 

 from the existence in these regions of an intensive upwelling of deep 

 water, resulting in the creation of zones of increased biologic 

 productivity. There is good reason to believe that commercial 

 concentrations of fish will be found over some of these underwater 

 elevations, with a total area of about 1.5*10° km^. 



The most productive zones, with the daily primary productivity of 

 about 1.2 g Z/w- and zooplankton biomass of over 100 mg/m-^, cover about 

 17% of the total area of the ocean. This is approximately the same 

 level of productivity as that of continental ecosystems--forests and 



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