, Volume 480, Issue 1–3, pp 29–39 | Cite as

Integrating classical and microbial food web concepts: evolving views from the open-ocean tropical Pacific

  • Michael R. Landry


Over the past half-century, and particularly the last two decades, new paradigms, perspectives and technological capabilities have greatly advanced our understanding of open-ocean pelagic ecosystems. Major new insights have come from the microbial loop concept and related discoveries, the iron limitation hypothesis and ocean time series. Focusing mainly on the tropical and subtropical Pacific Ocean, I review the influences of these new perspectives on classical views of food web complexity, phytoplankton regulation and diversity, and temporal dynamics. ``Microorganisms (bacteria, fungi, protozoa) are responsible for about 95% of the CO2evolved into the atmosphere, while animals contribute about 5%. These estimates are based on figures from terrestrial environments, but there is every reason to believe that microorganisms are relatively as important in the oceans''. (Lecture Note Handouts, OCN 434, Winter, 1971)

food web phytoplankton zooplankton bacteria protists Prochlorococcus grazing balance seasonal blooms nitrogen fixation climate 


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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • Michael R. Landry
    • 1
  1. 1.Department of OceanographyUniversity of Hawaii at ManoaHonoluluU.S.A

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