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<front>
<journal-meta>
<journal-id journal-id-type="publisher">BG</journal-id>
<journal-title-group>
<journal-title>Biogeosciences</journal-title>
<abbrev-journal-title abbrev-type="publisher">BG</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Biogeosciences</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1726-4189</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/bg-4-985-2007</article-id>
<title-group>
<article-title>The growing season greenhouse gas balance of a continental tundra site in the Indigirka lowlands, NE Siberia</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>van der Molen</surname>
<given-names>M. K.</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>van Huissteden</surname>
<given-names>J.</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>Parmentier</surname>
<given-names>F. J. W.</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>Petrescu</surname>
<given-names>A. M. R.</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>Dolman</surname>
<given-names>A. J.</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>Maximov</surname>
<given-names>T. C.</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>Kononov</surname>
<given-names>A. V.</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>Karsanaev</surname>
<given-names>S. V.</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>Suzdalov</surname>
<given-names>D. A.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Hydrology and Geo-Environmental Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Institute of Biological Problems of the Cryolithozone, Russian Academy of Sciences, Siberian Division, 41, Lenin Prospekt, Yakutsk, The Republic of Sakha (Yakutia), 677980, Russian Federation</addr-line>
</aff>
<pub-date pub-type="epub">
<day>14</day>
<month>11</month>
<year>2007</year>
</pub-date>
<volume>4</volume>
<issue>6</issue>
<fpage>985</fpage>
<lpage>1003</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2007 M. K. van der Molen et al.</copyright-statement>
<copyright-year>2007</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by-nc-sa/2.5/">https://creativecommons.org/licenses/by-nc-sa/2.5/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://bg.copernicus.org/articles/4/985/2007/bg-4-985-2007.html">This article is available from https://bg.copernicus.org/articles/4/985/2007/bg-4-985-2007.html</self-uri>
<self-uri xlink:href="https://bg.copernicus.org/articles/4/985/2007/bg-4-985-2007.pdf">The full text article is available as a PDF file from https://bg.copernicus.org/articles/4/985/2007/bg-4-985-2007.pdf</self-uri>
<abstract>
<p>Carbon dioxide and methane fluxes were measured at a tundra site near Chokurdakh, in the lowlands of the Indigirka river in north-east Siberia.
This site is one of the few stations on Russian tundra and it is different from most other tundra flux stations in its continentality. A suite
of methods was applied to determine the fluxes of NEE, GPP, &lt;i&gt;R&lt;/i&gt;&lt;sub&gt;eco&lt;/sub&gt; and methane, including eddy covariance, chambers and
leaf cuvettes. Net carbon dioxide fluxes were high compared with other tundra sites, with NEE=&amp;minus;92 g C m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; yr&lt;sup&gt;&amp;minus;1&lt;/sup&gt;, which is
composed of an &lt;i&gt;R&lt;/i&gt;&lt;sub&gt;eco&lt;/sub&gt;=+141 g C m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; yr&lt;sup&gt;&amp;minus;1&lt;/sup&gt; and GPP=&amp;minus;232 g C m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; yr&lt;sup&gt;&amp;minus;1&lt;/sup&gt;. This large carbon dioxide sink
may be explained by the continental climate, that is reflected in low winter soil temperatures (&amp;minus;14&amp;deg;C), reducing the respiration rates,
and short, relatively warm summers, stimulating high photosynthesis rates. Interannual variability in GPP was dominated by the
frequency of light limitation (&lt;i&gt;R&lt;sub&gt;g&lt;/sub&gt;&lt;/i&gt;&amp;lt;200 W m&lt;sup&gt;&amp;minus;2&lt;/sup&gt;), whereas &lt;i&gt;R&lt;/i&gt;&lt;sub&gt;eco&lt;/sub&gt; depends most directly on soil temperature and time in the
growing season, which serves as a proxy of the combined effects of active layer depth, leaf area index, soil moisture and substrate
availability. The methane flux, in units of global warming potential, was +28 g C-CO&lt;sub&gt;2&lt;/sub&gt;e m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; yr&lt;sup&gt;&amp;minus;1&lt;/sup&gt;, so that the greenhouse gas
balance was &amp;minus;64 g C-CO&lt;sub&gt;2&lt;/sub&gt;e m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; yr&lt;sup&gt;&amp;minus;1&lt;/sup&gt;. Methane fluxes depended only slightly on soil temperature and were highly sensitive to
hydrological conditions and vegetation composition.</p>
</abstract>
<counts><page-count count="19"/></counts>
</article-meta>
</front>
<body/>
<back>
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