<?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>Ann E. Brown</dc:contributor>
  <dc:creator>John R. Ritter</dc:creator>
  <dc:date>1981</dc:date>
  <dc:description>Analyses of water collected at 32 sites on headwater streams in Pennsylvania during low-flow conditions in 1970-80 were compared to pre-1971 data to evaluate whether acid rain had changed the chemistry of the streams in the previous decade. Most pH, alkalinity, and sulfate values of the samples collected in 1970-80 fell within the ranges of values for samples collected before 1971. The limited data indicate, however, that pH may have increased and alkalinity and sulfate may have decreased with time.</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.3133/ofr811025</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>U.S. Geological Survey</dc:publisher>
  <dc:title>An evaluation of the effects of acid rain on low conductivity headwater streams in Pennsylvania</dc:title>
  <dc:type>reports</dc:type>
</oai_dc:dc>