Accession Number : AD0717965

Title :   Primary and Secondary Production in the Tropical Atlantic.

Descriptive Note : Final rept. Aug 67-Sep 69,

Corporate Author : BERMUDA BIOLOGICAL STATION ST GEORGE'S WEST

Personal Author(s) : Steven,David M. ; Brooks,Albert L. ; Moore,Euna A.

Report Date : DEC 1970

Pagination or Media Count : 132

Abstract : Forty-eight collections were made for a study of primary and secondary production at a station in 460 m of water, between 29 August 1967 and 1 September 1969, and 22 additional collections at 17 deep water stations within a radius of 100 miles from Barbados. Primary production by carbon fixation lacked seasonal variation and annual production was estimated at 117 g C /sq m/year. Predictable seasonal variations were also lacking in concentrations of nutrients and in the composition and quantity of phytoplankton and zooplankton. However evidence was obtained of oscillations with a two to four months' periodicity in the concentration of chlorophyll and the numbers of Trichodesmium, which is the most important phytoplankton of the surface waters. This is tentatively ascribed to a short term growth and decay cycle which may be determined by grazing by zooplankton. Additional information was obtained on an inverse correlation between salinity and silicate concentration in the surface water previously reported. The low salinity/high silicate water found off Barbados at various times from January to August appears to originate with the Amazon River outflow and is identified with the fresh water lenses some 500 miles to the east of the island. (Author)

Descriptors :   (*ECOLOGY, *ATLANTIC OCEAN), PLANKTON, SALINITY, FERTILITY, NUTRITION, SEA WATER, CHEMICAL PROPERTIES, CHLOROPHYLLS, AQUATIC ANIMALS, PERIODIC VARIATIONS

Subject Categories : Biological Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE