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<front>
<journal-meta>
<journal-id journal-id-type="publisher">OS</journal-id>
<journal-title-group>
<journal-title>Ocean Science</journal-title>
<abbrev-journal-title abbrev-type="publisher">OS</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Ocean Sci.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1812-0792</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/os-9-489-2013</article-id>
<title-group>
<article-title>Springtime contribution of dinitrogen fixation to primary production across the Mediterranean Sea</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rahav</surname>
<given-names>E.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Herut</surname>
<given-names>B.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Levi</surname>
<given-names>A.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Mulholland</surname>
<given-names>M. R.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Berman-Frank</surname>
<given-names>I.</given-names>
<ext-link>https://orcid.org/0000-0003-3497-1844</ext-link>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Israel Oceanographic and Limnological Research, National Institute of Oceanography, Haifa 31080, Israel</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Department of Ocean, Earth and Atmospheric Sciences, Old Dominion University, 4600 Elkhorn Avenue, Norfolk, Virginia 23 529-0276, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>14</day>
<month>05</month>
<year>2013</year>
</pub-date>
<volume>9</volume>
<issue>3</issue>
<fpage>489</fpage>
<lpage>498</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2013 E. Rahav et al.</copyright-statement>
<copyright-year>2013</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/3.0/">https://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://os.copernicus.org/articles/9/489/2013/os-9-489-2013.html">This article is available from https://os.copernicus.org/articles/9/489/2013/os-9-489-2013.html</self-uri>
<self-uri xlink:href="https://os.copernicus.org/articles/9/489/2013/os-9-489-2013.pdf">The full text article is available as a PDF file from https://os.copernicus.org/articles/9/489/2013/os-9-489-2013.pdf</self-uri>
<abstract>
<p>Dinitrogen (N&lt;sub&gt;2&lt;/sub&gt;) fixation rates were measured during early spring across
the different provinces of Mediterranean Sea surface waters. N&lt;sub&gt;2&lt;/sub&gt; fixation
rates, measured using &lt;sup&gt;15&lt;/sup&gt;N&lt;sub&gt;2&lt;/sub&gt; enriched seawater, were lowest in the
eastern basin and increased westward with a maximum at the Strait of
Gibraltar (0.10 to 2.35 nmol N L&lt;sup&gt;−1&lt;/sup&gt; d&lt;sup&gt;−1&lt;/sup&gt;, respectively). These
rates were 3–7 fold higher than N&lt;sub&gt;2&lt;/sub&gt; fixation rates measured previously
in the Mediterranean Sea during summertime and we estimated that
methodological differences alone did not account for the seasonal changes we
observed. Higher contribution of N&lt;sub&gt;2&lt;/sub&gt; fixation to primary production
(4–8%) was measured in the western basin compared to the eastern basin
(&amp;sim;2%). Our data indicates that these differences between basins
may be attributed to changes in N&lt;sub&gt;2&lt;/sub&gt;-fixing planktonic communities and
that heterotrophic diazotrophy may play a significant role in the eastern
Mediterranean while autotrophic diazotrophy has a more dominant role in the
western basin.</p>
</abstract>
<counts><page-count count="10"/></counts>
</article-meta>
</front>
<body/>
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