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<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>David Butman</dc:contributor>
  <dc:contributor>Cory P. McDonald</dc:contributor>
  <dc:contributor>Sarah M. Stackpoole</dc:contributor>
  <dc:contributor>Michael D. DeGrandpre</dc:contributor>
  <dc:contributor>Robert G. Striegl</dc:contributor>
  <dc:creator>Edward G. Stets</dc:creator>
  <dc:date>2017</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;Multiple processes support the significant efflux of carbon dioxide (CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;) from rivers and streams. Attribution of CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;oversaturation will lead to better quantification of the freshwater carbon cycle and provide insights into the net cycling of nutrients and pollutants. CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;production is closely related to O&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;consumption because of the metabolic linkage of these gases. However, this relationship can be weakened due to dissolved inorganic carbon inputs from groundwater, carbonate buffering, calcification, and anaerobic metabolism. CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;and O&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;concentrations and other water quality parameters were analyzed in two data sets: a synoptic field study and nationwide water quality monitoring data. CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;and O&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;concentrations were strongly negatively correlated in both data sets (&lt;/span&gt;&lt;i&gt;ρ&lt;/i&gt;&lt;span&gt; = −0.67 and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;/span&gt;&lt;i&gt;ρ&lt;/i&gt;&lt;span&gt; = −0.63, respectively), although the correlations were weaker in high-alkalinity environments. In nearly all samples, the molar oversaturation of CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;was a larger magnitude than molar O&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;undersaturation. We used a dynamically coupled O&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif" alt="[BOND]" data-mce-src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/00f8ff.gif"&gt;&lt;span&gt;CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;model to show that lags in CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;air-water equilibration are a likely cause of this phenomenon. Lags in CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;equilibration also impart landscape-scale differences in the behavior of CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;between high- and low-alkalinity watersheds. Although the concept of carbonate buffering and how it creates lags in CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;equilibration with the atmosphere is well understood, it has not been sufficiently integrated into our understanding of CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;dynamics in freshwaters. We argue that the consideration of carbonate equilibria and its effects on CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;dynamics are primary steps in understanding the sources and magnitude of CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;oversaturation in rivers and streams.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1002/2016GB005578</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>American Geophysical Union</dc:publisher>
  <dc:title>Carbonate buffering and metabolic controls on carbon dioxide in rivers</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>