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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACP</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACP</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7324</issn>
<publisher><publisher-name>Copernicus GmbH</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acp-10-1617-2010</article-id>
<title-group>
<article-title>BVOC ecosystem flux measurements at a high latitude wetland site</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Holst</surname>
<given-names>T.</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>Arneth</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>Hayward</surname>
<given-names>S.</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>Ekberg</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>Mastepanov</surname>
<given-names>M.</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>Jackowicz-Korczynski</surname>
<given-names>M.</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>Friborg</surname>
<given-names>T.</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>Crill</surname>
<given-names>P. M.</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>Bäckstrand</surname>
<given-names>K.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Department of Physical Geography and Ecosystems Analysis, Lund University, Sweden</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Geography and Geology, University of Copenhagen, Denmark</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Department of Geology and Geochemistry, Stockholm University, Sweden</addr-line>
</aff>
<pub-date pub-type="epub">
<day>15</day>
<month>02</month>
<year>2010</year>
</pub-date>
<volume>10</volume>
<issue>4</issue>
<fpage>1617</fpage>
<lpage>1634</lpage>
<permissions>
<license xlink:type="simple">
<license-p>This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</license-p>
</license>
</permissions>
<self-uri xlink:href="http://www.atmos-chem-phys.net/10/1617/2010/acp-10-1617-2010.html">This article is available from http://www.atmos-chem-phys.net/10/1617/2010/acp-10-1617-2010.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys.net/10/1617/2010/acp-10-1617-2010.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/1617/2010/acp-10-1617-2010.pdf</self-uri>
<abstract>
<p>In this study, we present summertime concentrations and fluxes of biogenic
volatile organic compounds (BVOCs) measured at a sub-arctic wetland in
northern Sweden using a disjunct eddy-covariance (DEC) technique based on a
proton transfer reaction mass spectrometer (PTR-MS). The vegetation at the
site was dominated by &lt;i&gt;Sphagnum&lt;/i&gt;, &lt;i&gt;Carex&lt;/i&gt; and
\textit{Eriophorum} spp. The measurements reported here cover a
period of 50 days (1 August to 19 September 2006), approximately one half of
the growing season at the site, and allowed to investigate the effect of
day-to-day variation in weather as well as of vegetation senescence on daily
BVOC fluxes, and on their temperature and light responses. The sensitivity
drift of the DEC system was assessed by comparing H&lt;sub&gt;3&lt;/sub&gt;O&lt;sup&gt;+&lt;/sup&gt;-ion cluster
formed with water molecules (H&lt;sub&gt;3&lt;/sub&gt;O&lt;sup&gt;+&lt;/sup&gt;(H&lt;sub&gt;2&lt;/sub&gt;O) at m37) with water
vapour concentration measurements made using an adjacent humidity sensor,
and the applicability of the DEC method was analysed by a comparison of
sensible heat fluxes for high frequency and DEC data obtained from the sonic
anemometer. These analyses showed no significant PTR-MS sensor drift over a
period of several weeks and only a small flux-loss due to high-frequency
spectrum omissions. This loss was within the range expected from other
studies and the theoretical considerations.
&lt;br&gt;&lt;br&gt;
Standardised (20 &amp;deg;C and 1000 &amp;mu;mol m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; s&lt;sup&gt;&amp;minus;1&lt;/sup&gt; PAR) summer
isoprene emission rates found in this study of 329 &amp;mu;g C m&lt;sup&gt;&amp;minus;2&lt;/sup&gt;
(ground area) h&lt;sup&gt;&amp;minus;1&lt;/sup&gt; were comparable with findings from
more southern boreal forests, and fen-like ecosystems. On a diel scale,
measured fluxes indicated a stronger temperature dependence than emissions
from temperate or (sub)tropical ecosystems. For the first time, to our
knowledge, we report ecosystem methanol fluxes from a sub-arctic ecosystem.
Maximum daytime emission fluxes were around 270 &amp;mu;g m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; h&lt;sup&gt;&amp;minus;1&lt;/sup&gt;
(ca. 100 &amp;mu;g C m&lt;sup&gt;&amp;minus;2&lt;/sup&gt; h&lt;sup&gt;&amp;minus;1&lt;/sup&gt;), and during most nights small negative
fluxes directed from the atmosphere to the surface were observed.</p>
</abstract>
<counts><page-count count="18"/></counts>
</article-meta>
</front>
<body/>
<back>
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