<?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>Edward P. Glenn</dc:contributor>
  <dc:contributor>Glenn R. Guntenspergen</dc:contributor>
  <dc:contributor>J. Jed Brown</dc:contributor>
  <dc:contributor>Stephen G. Nelson</dc:contributor>
  <dc:creator>Edward A. Vasquez</dc:creator>
  <dc:date>2006</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;An invasive variety of &lt;/span&gt;&lt;i&gt;Phragmites australis&lt;/i&gt;&lt;span&gt; (Poaceae, common reed), the M haplotype, has been implicated in the spread of this species into North American salt marshes that are normally dominated by the salt marsh grass &lt;/span&gt;&lt;i&gt;Spartina alterniflora&lt;/i&gt;&lt;span&gt; (Poaceae, smooth cordgrass). In some European marshes, on the other hand, &lt;/span&gt;&lt;i&gt;Spartina&lt;/i&gt;&lt;span&gt; spp. derived from &lt;/span&gt;&lt;i&gt;S. alterniflora&lt;/i&gt;&lt;span&gt; have spread into brackish &lt;/span&gt;&lt;i&gt;P. australis&lt;/i&gt;&lt;span&gt; marshes. In both cases, the non-native grass is thought to degrade the habitat value of the marsh for wildlife, and it is important to understand the physiological processes that lead to these species replacements. We compared the growth, salt tolerance, and osmotic adjustment of M haplotype &lt;/span&gt;&lt;i&gt;P. australis&lt;/i&gt;&lt;span&gt; and &lt;/span&gt;&lt;i&gt;S. alterniflora&lt;/i&gt;&lt;span&gt; along a salinity gradient in greenhouse experiments. &lt;/span&gt;&lt;i&gt;Spartina alterniflora&lt;/i&gt;&lt;span&gt; produced new biomass up to 0.6 M NaCl, whereas &lt;/span&gt;&lt;i&gt;P. australis&lt;/i&gt;&lt;span&gt; did not grow well above 0.2 M NaCl. The greater salt tolerance of &lt;/span&gt;&lt;i&gt;S. alterniflora&lt;/i&gt;&lt;span&gt; compared with &lt;/span&gt;&lt;i&gt;P. australis&lt;/i&gt;&lt;span&gt; was due to its ability to use Na&lt;/span&gt;&lt;sup&gt;+&lt;/sup&gt;&lt;span&gt; for osmotic adjustment in the shoots. On the other hand, at low salinities &lt;/span&gt;&lt;i&gt;P. australis&lt;/i&gt;&lt;span&gt; produced more shoots per gram of rhizome tissue than did &lt;/span&gt;&lt;i&gt;S. alterniflora&lt;/i&gt;&lt;span&gt;. This study illustrates how ecophysiological differences can shift the competitive advantage from one species to another along a stress gradient. &lt;/span&gt;&lt;i&gt;Phragmites australis&lt;/i&gt;&lt;span&gt; is spreading into North American coastal marshes that are experiencing reduced salinities, while &lt;/span&gt;&lt;i&gt;Spartina&lt;/i&gt;&lt;span&gt; spp. are spreading into northern European brackish marshes that are experiencing increased salinities as land use patterns change on the two continents.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.3732/ajb.93.12.1784</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Botanical Society of America</dc:publisher>
  <dc:title>Salt tolerance and osmotic adjustment of Spartina alterniflora (Poaceae) and the invasive M haplotype of Phragmites australis (Poaceae) along a salinity gradient</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>