Record Display for the EPA National Library Catalog


Main Title Possible Influence of Hydrogen Concentration on Microbial Methane Stable Hydrogen Isotopic Composition.
Author Burke, R. A. ;
CORP Author Environmental Research Lab., Athens, GA.
Publisher c1993
Year Published 1993
Report Number EPA/600/J-93/229;
Stock Number PB93-205128
Additional Subjects Air pollution ; Methane ; Hydrogen isotopes ; Microbial degradation ; Organic matter ; Natural emissions ; Combustion products ; Pollution sources ; Atmospheric chemistry ; Sediments ; Carbon dioxide ; Carbon isotopes ; Oxidation ; Wetlands ; Chemical reactions ; Reprints ;
Library Call Number Additional Info Location Last
NTIS  PB93-205128 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 15p
Factors affecting the stable hydrogen isotopic composition (delta D) of important sources of microbial methane to the atmosphere include oxidation, methanogenic precursor (e.g., acetate vs. CO2/H2), and the delta D of the environmental water. Variations in hydrogen gas concentrations or rates of interspecies hydrogen transfer resulting from variations in organic matter degradation rates may also affect delta D-CH4. Methane produced via CO2 reduction by laboratory cultures was more D-depleted than methane produced in shallow marine sediments from CO2/H2. The dissolved hydrogen gas concentration in that laboratory culture was about 1mM; whereas, hydrogen concentrations in methane-zone sediments typically range between 10 and 100 nM. The relatively greater hydrogen isotope fractionation in the culture appears to result from the incorporation into methane of protons that are produced intracellularly from the hydrogenase-catalyzed oxidation of hydrogen gas.