Accession Number : ADA332971

Title :   Method Development for Unenclosed Mesoscale Iron Enrichment Experiment.

Descriptive Note : Final rept. 1 Oct 93-31 Jul 97,

Corporate Author : MOSS LANDING MARINE LABS CA

Personal Author(s) : Johnson, Kenneth ; Coale, Kenneth

PDF Url : ADA332971

Report Date : 15 DEC 1997

Pagination or Media Count : 7

Abstract : The long-term goals of this work were to test the hypothesis that metals, especially iron, regulate rates of primary production in High Nutrient, Low Chlorophyll (HNLC) areas of the ocean. Two open ocean, iron enrichments were conducted in the eastern equatorial Pacific. Four nM iron was added in a single addition during the first experiment (Oct. 1993) and in three separate additions of 2, 1 and 1 nM in the second (May 1995). There was a strong response of the ecosystem with increases in primary production rates and plankton biomass. Large changes in bio-optical properties were also observed. The second experiment, in which higher iron concentrations were sustained for 1 week, produced a 20-fold increase in chlorophyll - a proxy for photoplankton biomass. The results of the experiments have been reported in some 20 journal articles.

Descriptors :   *IRON, *OCEANS, *OPEN WATER, EQUATORIAL REGIONS, METALS, NUTRIENTS, CONCENTRATION(COMPOSITION), ECOSYSTEMS, MARINE BIOLOGY, HYPOTHESES, PACIFIC OCEAN, PRODUCTION RATE, EVOLUTION(DEVELOPMENT), TRACE ELEMENTS, PLANKTON, BIOMASS CONVERSION, CHLOROPHYLLS.

Subject Categories : Inorganic Chemistry
      Physical and Dynamic Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE