ECHO-SOUNDING RECORDS OF MACROPLANKTON CONCENTRATIONS AND THEIR DISTRIBUTION IN THE PACIFIC OCEAN,
Abstract
Kelvin and Hughes' MS-26 echo-sounders chiefly used in our surveys can detect concentrations of forage organisms down to 0.01 organisms per 1 cu m. The Pacific Ocean had been divided into 17 'natural areas' and the vertical and the horizontal distribution of scattering layers in these areas were described. In all areas there are non-migratory layers; the deepest of them can be found as deep as 720 m. Migratory layers are chiefly typical of tropical areas; they are confined to the intermediate water layer with a considerable temperature gradient and do neither rise into the surface mixed layer nor sink into homogenous deep waters. In anomalous 1957 and 1958, migratory layers were weekly represented in affected regions of both the Pacific and the Indian Oceans and non-migratory DSL in the upper water layers were over-developed as compared with previous and subsequent years. Detectable concentrations of forage organisms were more frequenctly found in productive (subarctic and equatorial) areas then in Central Waters. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1967
- Accession Number
- AD0663026
Entities
People
- K. V. Beklemishev
Organizations
- Naval Oceanographic Office