Isotopic fractionation during soil uptake of atmospheric hydrogen
Soil uptake of atmospheric hydrogen (H<sub>2</sub>) and the associated hydrogen isotope effect were studied using soil chambers in a Western Washington second-growth coniferous forest. Chamber studies were conducted during both winter and summer seasons to account for lar...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2011-03-01
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| Series: | Biogeosciences |
| Online Access: | http://www.biogeosciences.net/8/763/2011/bg-8-763-2011.pdf |
| _version_ | 1818484217880772608 |
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| author | A. Rice A. Dayalu P. Quay R. Gammon |
| author_facet | A. Rice A. Dayalu P. Quay R. Gammon |
| author_sort | A. Rice |
| collection | DOAJ |
| description | Soil uptake of atmospheric hydrogen (H<sub>2</sub>) and the associated hydrogen isotope effect were studied using soil chambers in a Western Washington second-growth coniferous forest. Chamber studies were conducted during both winter and summer seasons to account for large natural variability in soil moisture content (4–50%) and temperature (6–22 &deg;C). H<sub>2</sub> deposition velocities were found to range from 0.01–0.06 cm s<sup>&minus;1</sup> with an average of 0.033 &plusmn; 0.008 cm s<sup>&minus;1</sup> (95% confidence interval). Consistent with prior studies, deposition velocities were correlated with soil moisture below 20% soil moisture content during the summer season. During winter, there was considerable variability observed in deposition velocity that was not closely related to soil moisture. The hydrogen kinetic isotope effect with H<sub>2</sub> uptake was found to range from &minus;24&permil; to −109&permil;. Aggregate analysis of experimental data results in an average KIE of &minus;57 &plusmn; 5&permil; (95% CI). Some of the variability in KIE can be explained by larger isotope effects at lower (<10%) and higher (>30%) soil moisture contents. The measured KIE was also found to be correlated with deposition velocity, with smaller isotope effects occurring at higher deposition velocities. If correct, these findings will have an impact on the interpretation of atmospheric measurements and modeling of &delta;D of H<sub>2</sub>. |
| first_indexed | 2024-12-10T15:52:12Z |
| format | Article |
| id | doaj.art-23a31448021c44778f154f8c3cb79e26 |
| institution | Directory Open Access Journal |
| issn | 1726-4170 1726-4189 |
| language | English |
| last_indexed | 2024-12-10T15:52:12Z |
| publishDate | 2011-03-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Biogeosciences |
| spelling | doaj.art-23a31448021c44778f154f8c3cb79e262022-12-22T01:42:45ZengCopernicus PublicationsBiogeosciences1726-41701726-41892011-03-018376376910.5194/bg-8-763-2011Isotopic fractionation during soil uptake of atmospheric hydrogenA. RiceA. DayaluP. QuayR. GammonSoil uptake of atmospheric hydrogen (H<sub>2</sub>) and the associated hydrogen isotope effect were studied using soil chambers in a Western Washington second-growth coniferous forest. Chamber studies were conducted during both winter and summer seasons to account for large natural variability in soil moisture content (4–50%) and temperature (6–22 &deg;C). H<sub>2</sub> deposition velocities were found to range from 0.01–0.06 cm s<sup>&minus;1</sup> with an average of 0.033 &plusmn; 0.008 cm s<sup>&minus;1</sup> (95% confidence interval). Consistent with prior studies, deposition velocities were correlated with soil moisture below 20% soil moisture content during the summer season. During winter, there was considerable variability observed in deposition velocity that was not closely related to soil moisture. The hydrogen kinetic isotope effect with H<sub>2</sub> uptake was found to range from &minus;24&permil; to −109&permil;. Aggregate analysis of experimental data results in an average KIE of &minus;57 &plusmn; 5&permil; (95% CI). Some of the variability in KIE can be explained by larger isotope effects at lower (<10%) and higher (>30%) soil moisture contents. The measured KIE was also found to be correlated with deposition velocity, with smaller isotope effects occurring at higher deposition velocities. If correct, these findings will have an impact on the interpretation of atmospheric measurements and modeling of &delta;D of H<sub>2</sub>.http://www.biogeosciences.net/8/763/2011/bg-8-763-2011.pdf |
| spellingShingle | A. Rice A. Dayalu P. Quay R. Gammon Isotopic fractionation during soil uptake of atmospheric hydrogen Biogeosciences |
| title | Isotopic fractionation during soil uptake of atmospheric hydrogen |
| title_full | Isotopic fractionation during soil uptake of atmospheric hydrogen |
| title_fullStr | Isotopic fractionation during soil uptake of atmospheric hydrogen |
| title_full_unstemmed | Isotopic fractionation during soil uptake of atmospheric hydrogen |
| title_short | Isotopic fractionation during soil uptake of atmospheric hydrogen |
| title_sort | isotopic fractionation during soil uptake of atmospheric hydrogen |
| url | http://www.biogeosciences.net/8/763/2011/bg-8-763-2011.pdf |
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