Regeneration of nitrogen by zooplankton and fish in the Northwest Africa and Peru upwelling ecosystems

Technical Report · Thu Jan 01 04:00:00 EST 1976

DOI:https://doi.org/10.2172/7319257· OSTI ID:7319257

Whitledge, T E

The availability of nutrients and light are the dominant controlling factors of the levels of primary production in the ocean. In the lower latitudes where most coastal upwelling areas are located, the amount of light is seldom below the critical level to inhibit productivity so nutrients are often the limiting factor in phytoplankton growth. Nutrients utilized in primary productivity are derived from two sources in upwelling areas. Nutrients are introduced to the euphotic zone from depth by the physical processes that create upwelling and nutrients are recycled by biological organisms that inhabit the area. Nitrate introduced into the euphotic zone by upwelling supports new productivity while ammonium and other excretory products regenerated by zooplankton and nekton supports regenerated productivity. Results are reported from studies off the coast of Northwest Africa and Peru using /sup 15/N as a tracer that showed that recycled ammonium may fulfill nearly half of the daily nitrogen requirement of phytoplankton and upwelled nitrate may provide the other half.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• Sponsoring Organization: USDOE
• DOE Contract Number: E(30-1)-16
• OSTI ID: 7319257
• Report Number(s): BNL-21899
• Country of Publication: United States
• Language: English

Related Subjects

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54 ENVIRONMENTAL SCIENCES
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59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMMONIA
ANIMALS
AQUATIC ORGANISMS
ATLANTIC OCEAN
BIOMASS
CARBOXYLIC ACIDS
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CHEMISTRY
CHLOROPHYLL
COASTAL WATERS
DEPTH
DIMENSIONS
ENERGY SOURCES
FISHES
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDRIDES
HYDROGEN COMPOUNDS
METABOLISM
MIXING
NITRATES
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NUTRIENTS
OCEANOGRAPHY
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOCHEMISTRY
PHOTOSYNTHESIS
PHYTOCHROMES
PHYTOPLANKTON
PIGMENTS
PLANKTON
PORPHYRINS
PRODUCTIVITY
RENEWABLE ENERGY SOURCES
SEAS
SEAWATER
SURFACE WATERS
SYNTHESIS
TROPICAL REGIONS
VERTEBRATES
WATER
ZOOPLANKTON