ABSTRACT Seven years of time-series observations of biogeochemical processes in the subtropical North Pacific Ocean gyre have revealed dramatic changes in the microbial community structure

and in the mechanisms of nutrient cycling in response to large-scale ocean–atmosphere interactions. Several independent lines of evidence show that the fixation of atmospheric nitrogen by

cyanobacteria can fuel up to half of the new production. These and other observations demand a reassessment of present views of nutrient and carbon cycling in one of the Earth′s largest

biomes. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution ACCESS OPTIONS Access through your institution Subscribe to

support SIMILAR CONTENT BEING VIEWED BY OTHERS IMPACT OF INTENSIFYING NITROGEN LIMITATION ON OCEAN NET PRIMARY PRODUCTION IS FINGERPRINTED BY NITROGEN ISOTOPES Article Open access 28

October 2021 THE ANGOLA GYRE IS A HOTSPOT OF DINITROGEN FIXATION IN THE SOUTH ATLANTIC OCEAN Article Open access 30 June 2022 THE ROLE OF ENVIRONMENTAL FACTORS IN THE LONG-TERM EVOLUTION OF

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  ADS  Google Scholar  Download references ACKNOWLEDGEMENTS We thank the HOT Program scientists and staff, and the officers and crew members of the research vessels used in our field work

for making this study possible, and E. Laws for comments on the manuscript. This work was supported in part by the National Science Foundation. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS *

Department of Oceanography, School of Ocean and Earth Science and Technology, University of Hawaii, Honolulu, 96822, Hawaii, USA D. Karl, L. Tupas, J. Dore & D. Hebel * College of

Oceanic and Atmospheric Sciences, Oregon State University, Corvallis, 97331-5503, Oregon , USA R. Letelier * Aquasearch Inc., 73-4460 Queen Kaahumanu Highway, Suite 110, Kailua-Kona, 96740,

Hawaii, USA J. Dore * Department of Oceanography, Dalhousie University, Halifax, B3H 4J1, Nova Scotia, Canada J. Christian Authors * D. Karl View author publications You can also search for

this author inPubMed Google Scholar * R. Letelier View author publications You can also search for this author inPubMed Google Scholar * L. Tupas View author publications You can also search

for this author inPubMed Google Scholar * J. Dore View author publications You can also search for this author inPubMed Google Scholar * J. Christian View author publications You can also

search for this author inPubMed Google Scholar * D. Hebel View author publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to D. Karl.

RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Karl, D., Letelier, R., Tupas, L. _et al._ The role of nitrogen fixation in biogeochemical cycling in

the subtropical North Pacific Ocean. _Nature_ 388, 533–538 (1997). https://doi.org/10.1038/41474 Download citation * Received: 04 June 1997 * Accepted: 27 June 1997 * Issue Date: 07 August

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