Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer
<p>The terrestrial subsurface is the largest source of freshwater globally. The organic carbon contained within it and processes controlling its concentration remain largely unknown. The global median concentration of dissolved organic carbon (DOC) in groundwater is low compared to surface wat...
| প্রধান লেখক: | , , , , , , , , |
|---|---|
| বিন্যাস: | প্রবন্ধ |
| ভাষা: | English |
| প্রকাশিত: |
Copernicus Publications
2020-04-01
|
| মালা: | Hydrology and Earth System Sciences |
| অনলাইন ব্যবহার করুন: | https://www.hydrol-earth-syst-sci.net/24/2167/2020/hess-24-2167-2020.pdf |
| _version_ | 1828772149425340416 |
|---|---|
| author | K. T. Meredith K. T. Meredith A. Baker A. Baker M. S. Andersen M. S. Andersen D. M. O'Carroll D. M. O'Carroll H. Rutlidge H. Rutlidge L. K. McDonough L. K. McDonough P. Oudone P. Oudone E. Bryan N. S. Zainuddin |
| author_facet | K. T. Meredith K. T. Meredith A. Baker A. Baker M. S. Andersen M. S. Andersen D. M. O'Carroll D. M. O'Carroll H. Rutlidge H. Rutlidge L. K. McDonough L. K. McDonough P. Oudone P. Oudone E. Bryan N. S. Zainuddin |
| author_sort | K. T. Meredith |
| collection | DOAJ |
| description | <p>The terrestrial subsurface is the largest source of
freshwater globally. The organic carbon contained within it and processes
controlling its concentration remain largely unknown. The global median
concentration of dissolved organic carbon (DOC) in groundwater is low
compared to surface waters, suggesting significant processing in the
subsurface. Yet the processes that remove this DOC in groundwater are not
fully understood. The purpose of this study was to investigate the different
sources and processes influencing DOC in a shallow anoxic coastal aquifer.
Uniquely, this study combines liquid chromatography organic carbon detection
with organic (<span class="inline-formula"><i>δ</i><sup>13</sup>C</span><span class="inline-formula"><sub>DOC</sub></span>) carbon isotope geochemical
analyses to fingerprint the various DOC sources that influence the
concentration, carbon isotopic composition, and character with respect to distance from
surface water sources, depth below surface, and inferred groundwater
residence time (using <span class="inline-formula"><sup>3</sup>H</span> activities) in groundwater. It was found that
the average groundwater DOC concentration was 5 times higher
(5 mg L<span class="inline-formula"><sup>−1</sup></span>) than the global median concentration and that the concentration doubled
with depth at our site, but the chromatographic character did not change
significantly. The anoxic saturated conditions of the aquifer limited the
rate of organic matter processing, leading to enhanced preservation and
storage of the DOC sources from peats and palaeosols contained within the
aquifer. All groundwater samples were more aromatic for their molecular
weight in comparison to other lakes, rivers and surface marine samples
studied. The destabilization or changes in hydrology, whether by
anthropogenic or natural processes, could lead to the flux of up to 10 times
more unreacted organic carbon from this coastal aquifer compared to
deeper inland aquifers.</p> |
| first_indexed | 2024-12-11T14:38:27Z |
| format | Article |
| id | doaj.art-0ff684da968345ee9a394562d2ce0612 |
| institution | Directory Open Access Journal |
| issn | 1027-5606 1607-7938 |
| language | English |
| last_indexed | 2024-12-11T14:38:27Z |
| publishDate | 2020-04-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Hydrology and Earth System Sciences |
| spelling | doaj.art-0ff684da968345ee9a394562d2ce06122022-12-22T01:02:03ZengCopernicus PublicationsHydrology and Earth System Sciences1027-56061607-79382020-04-01242167217810.5194/hess-24-2167-2020Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquiferK. T. Meredith0K. T. Meredith1A. Baker2A. Baker3M. S. Andersen4M. S. Andersen5D. M. O'Carroll6D. M. O'Carroll7H. Rutlidge8H. Rutlidge9L. K. McDonough10L. K. McDonough11P. Oudone12P. Oudone13E. Bryan14N. S. Zainuddin15Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW 2234, AustraliaConnected Waters Initiative Research Centre, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaConnected Waters Initiative Research Centre, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaSchool of Biological, Earth and Environmental Sciences, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaConnected Waters Initiative Research Centre, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaSchool of Civil and Environmental Engineering, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaConnected Waters Initiative Research Centre, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaSchool of Civil and Environmental Engineering, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaConnected Waters Initiative Research Centre, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaSchool of Civil and Environmental Engineering, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaConnected Waters Initiative Research Centre, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaSchool of Biological, Earth and Environmental Sciences, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaConnected Waters Initiative Research Centre, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaSchool of Biological, Earth and Environmental Sciences, UNSW Sydney, High St., Kensington, New South Wales 2052, AustraliaGolder Associates, 124 Pacific Highway, St. Leonards, Sydney, New South Wales 2065, AustraliaFaculty of Civil Engineering, Universiti Teknologi MARA, Shah Alam, Selangor, Malaysia<p>The terrestrial subsurface is the largest source of freshwater globally. The organic carbon contained within it and processes controlling its concentration remain largely unknown. The global median concentration of dissolved organic carbon (DOC) in groundwater is low compared to surface waters, suggesting significant processing in the subsurface. Yet the processes that remove this DOC in groundwater are not fully understood. The purpose of this study was to investigate the different sources and processes influencing DOC in a shallow anoxic coastal aquifer. Uniquely, this study combines liquid chromatography organic carbon detection with organic (<span class="inline-formula"><i>δ</i><sup>13</sup>C</span><span class="inline-formula"><sub>DOC</sub></span>) carbon isotope geochemical analyses to fingerprint the various DOC sources that influence the concentration, carbon isotopic composition, and character with respect to distance from surface water sources, depth below surface, and inferred groundwater residence time (using <span class="inline-formula"><sup>3</sup>H</span> activities) in groundwater. It was found that the average groundwater DOC concentration was 5 times higher (5 mg L<span class="inline-formula"><sup>−1</sup></span>) than the global median concentration and that the concentration doubled with depth at our site, but the chromatographic character did not change significantly. The anoxic saturated conditions of the aquifer limited the rate of organic matter processing, leading to enhanced preservation and storage of the DOC sources from peats and palaeosols contained within the aquifer. All groundwater samples were more aromatic for their molecular weight in comparison to other lakes, rivers and surface marine samples studied. The destabilization or changes in hydrology, whether by anthropogenic or natural processes, could lead to the flux of up to 10 times more unreacted organic carbon from this coastal aquifer compared to deeper inland aquifers.</p>https://www.hydrol-earth-syst-sci.net/24/2167/2020/hess-24-2167-2020.pdf |
| spellingShingle | K. T. Meredith K. T. Meredith A. Baker A. Baker M. S. Andersen M. S. Andersen D. M. O'Carroll D. M. O'Carroll H. Rutlidge H. Rutlidge L. K. McDonough L. K. McDonough P. Oudone P. Oudone E. Bryan N. S. Zainuddin Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer Hydrology and Earth System Sciences |
| title | Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer |
| title_full | Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer |
| title_fullStr | Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer |
| title_full_unstemmed | Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer |
| title_short | Isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer |
| title_sort | isotopic and chromatographic fingerprinting of the sources of dissolved organic carbon in a shallow coastal aquifer |
| url | https://www.hydrol-earth-syst-sci.net/24/2167/2020/hess-24-2167-2020.pdf |
| work_keys_str_mv | AT ktmeredith isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT ktmeredith isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT abaker isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT abaker isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT msandersen isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT msandersen isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT dmocarroll isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT dmocarroll isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT hrutlidge isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT hrutlidge isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT lkmcdonough isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT lkmcdonough isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT poudone isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT poudone isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT ebryan isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer AT nszainuddin isotopicandchromatographicfingerprintingofthesourcesofdissolvedorganiccarboninashallowcoastalaquifer |