<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Robert G. Striegl</dc:contributor>
  <dc:contributor>George R. Aiken</dc:contributor>
  <dc:creator>Edward G. Stets</dc:creator>
  <dc:date>2010</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;Carbon (C) cycling in freshwater lakes is intense but poorly integrated into our current understanding of overall C transport from the land to the oceans. We quantified dissolved organic carbon export (DOC&lt;/span&gt;&lt;sub&gt;&lt;span&gt;X&lt;/span&gt;&lt;/sub&gt;&lt;span&gt;) and compared it with modeled gross DOC mineralization (DOC&lt;/span&gt;&lt;span&gt;R&lt;/span&gt;&lt;span&gt;) to determine whether hydrologic or within-lake processes dominated DOC cycling in a small headwaters watershed in Minnesota, USA. We also used DOC optical properties to gather information about DOC sources. We then compared our results to a data set of approximately 1500 lakes in the Eastern USA (Eastern Lake Survey, ELS, data set) to place our results in context of lakes more broadly. In the open-basin lakes in our watershed (&lt;/span&gt;&lt;i&gt;n&lt;/i&gt;&lt;span&gt;&amp;nbsp;= 5), DOC&lt;/span&gt;&lt;sub&gt;&lt;span&gt;X&lt;/span&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;ranged from 60 to 183 g C m&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;2&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;&amp;nbsp;lake area yr&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;1&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;, whereas DOC&lt;/span&gt;&lt;span&gt;R&lt;/span&gt;&lt;span&gt;&amp;nbsp;ranged from 15 to 21 g C m&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;2&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;&amp;nbsp;lake area yr&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;1&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;, emphasizing that lateral DOC fluxes dominated. DOC&lt;/span&gt;&lt;sub&gt;&lt;span&gt;X&lt;/span&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;calculated in our study watershed clustered near the 75th percentile of open-basin lakes in the ELS data set, suggesting that these results were not unusual. In contrast, DOC&lt;/span&gt;&lt;sub&gt;&lt;span&gt;X&lt;/span&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;in closed-basin lakes (&lt;/span&gt;&lt;i&gt;n&lt;/i&gt;&lt;span&gt;&amp;nbsp;= 2) was approximately 5 g C m&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;2&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;&amp;nbsp;lake area yr&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;1&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;, whereas DOC&lt;/span&gt;&lt;span&gt;R&lt;/span&gt;&lt;span&gt;&amp;nbsp;was 37 to 42 g C m&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;2&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;&amp;nbsp;lake area yr&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;1&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;, suggesting that internal C cycling dominated. In the ELS data set, median DOC&lt;/span&gt;&lt;sub&gt;&lt;span&gt;X&lt;/span&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;was 32 and 12 g C m&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;2&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;&amp;nbsp;yr&lt;/span&gt;&lt;sup&gt;&lt;span&gt;&amp;minus;1&amp;nbsp;&lt;/span&gt;&lt;/sup&gt;&lt;span&gt;in open-basin and closed-basin lakes, respectively. Although not as high as what was observed in our study watershed, DOC&lt;/span&gt;&lt;sub&gt;&lt;span&gt;X&lt;/span&gt;&lt;/sub&gt;&lt;span&gt;&amp;nbsp;is an important component of lake C flux more generally, particularly in open-basin lakes.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1029/2010GB003815</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Academic Press</dc:publisher>
  <dc:title>Dissolved organic carbon export and internal cycling in small, headwater lakes</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>