DISTRIBUTION OF ZOOPLANKTON BIOMASS IN TH E SURFACE-LAYER OF THE PACIFIC

The distribution of zooplankton biomass (animals in the size range bet ween 0.2 and 20 mm) in the surface layer (0-100 m) of the Pacific was mapped. The results of the biomass determination on 54920 oceanographi c stations from the autors archive records from the National Oceanogra phic Data Center, Wahigton, and from the published sources were used i n the map construction. A set of correction factors were considered wh ich are related to the different ways of research methods: (a) by nets with different mesh sizes; (b) from different layers samples (from su rface down to 300 m); (c) with different methods of biomass evaluation (seston displacement volume, seston wet or dry weight, or zooplankton biomass calculated from individual weights or from animal's size dete rminations); (d) in different seasons. The overall mezoplankton biomas s stock in the 0-100 m layer of the Pacific was evaluated as 2.7 x 10( 9) tons (wet weight).