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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>Jon E. Keeley</dc:contributor>
  <dc:creator>B. A. Morton</dc:creator>
  <dc:date>1990</dc:date>
  <dc:description>&lt;p&gt;&lt;i&gt;Eleocharis acicularis&lt;/i&gt;&lt;span&gt;&amp;nbsp;(L.) R. &amp;amp; S. is a widely distributed submerged aquatic macrophyte. In southern California, it codominates shallow seasonal pools with the aquatic CAM plant&amp;nbsp;&lt;/span&gt;&lt;i&gt;Isoetes howellii&lt;/i&gt;&lt;span&gt;&amp;nbsp;Engelm. Like the latter species,&amp;nbsp;&lt;/span&gt;&lt;i&gt;E. acicularis&lt;/i&gt;&lt;span&gt;&amp;nbsp;is apparently restricted to uptake of free-CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;; bicarbonate uptake is negligible, as indicated by poor carbon fixation at pH 7 and higher oxygen evolution at pH 5 than at pH 8 across a range of free-CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&amp;nbsp;concentrations. Unlike&amp;nbsp;&lt;/span&gt;&lt;i&gt;Isoetes, Eleocharis&lt;/i&gt;&lt;span&gt;&amp;nbsp;does not have CAM photosynthesis, however it does have the capacity for a low level of carbon fixation in the dark.&amp;nbsp;&lt;/span&gt;&lt;sup&gt;14&lt;/sup&gt;&lt;span&gt;C tracer studies in the light reveal C&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;acids constitute 40–50% of the initial labeled products, however the leaves lack Kranz anatomy. It is suggested that in seasonal pools, photosynthesis by&amp;nbsp;&lt;/span&gt;&lt;i&gt;E. acicularis&lt;/i&gt;&lt;span&gt;&amp;nbsp;is highest in the early morning when ambient free-CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&amp;nbsp;levels are maximal. Such sites are typically overcast in the early morning and like&amp;nbsp;&lt;/span&gt;&lt;i&gt;I. howellii, E. acicularis&lt;/i&gt;&lt;span&gt;&amp;nbsp;is light saturated at relatively low irradiance levels. Throughout much of the day, free-CO&lt;/span&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;span&gt;&amp;nbsp;concentrations are limited and oxygen concentrations are high. PEP carboxylase mediated carbon fixation may be of selective value under such daytime conditions.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1016/0304-3770(90)90054-O</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Elsevier</dc:publisher>
  <dc:title>C4 acid fixation in photosynthesis of the submerged aquatic Eleocharis acicularis (L.) R. &amp; S</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>