Mineral protection regulates long-term global preservation of natural organic carbon
The balance between photosynthetic organic carbon production and respiration controls atmospheric composition and climate1,2. The majority of organic carbon is respired back to carbon dioxide in the biosphere, but a small fraction escapes remineralization and is preserved over geological timescales3...
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| Format: | Article |
| Language: | English |
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Springer Science and Business Media LLC
2020
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| Online Access: | https://hdl.handle.net/1721.1/126782 |
| _version_ | 1811093763460694016 |
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| author | Hemingway, Jordon Dennis |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Hemingway, Jordon Dennis |
| author_sort | Hemingway, Jordon Dennis |
| collection | MIT |
| description | The balance between photosynthetic organic carbon production and respiration controls atmospheric composition and climate1,2. The majority of organic carbon is respired back to carbon dioxide in the biosphere, but a small fraction escapes remineralization and is preserved over geological timescales3. By removing reduced carbon from Earth’s surface, this sequestration process promotes atmospheric oxygen accumulation2 and carbon dioxide removal1. Two major mechanisms have been proposed to explain organic carbon preservation: selective preservation of biochemically unreactive compounds4,5 and protection resulting from interactions with a mineral matrix6,7. Although both mechanisms can operate across a range of environments and timescales, their global relative importance on 1,000-year to 100,000-year timescales remains uncertain4. Here we present a global dataset of the distributions of organic carbon activation energy and corresponding radiocarbon ages in soils, sediments and dissolved organic carbon. We find that activation energy distributions broaden over time in all mineral-containing samples. This result requires increasing bond-strength diversity, consistent with the formation of organo-mineral bonds8 but inconsistent with selective preservation. Radiocarbon ages further reveal that high-energy, mineral-bound organic carbon persists for millennia relative to low-energy, unbound organic carbon. Our results provide globally coherent evidence for the proposed7 importance of mineral protection in promoting organic carbon preservation. We suggest that similar studies of bond-strength diversity in ancient sediments may reveal how and why organic carbon preservation—and thus atmospheric composition and climate—has varied over geological time. |
| first_indexed | 2024-09-23T15:50:16Z |
| format | Article |
| id | mit-1721.1/126782 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T15:50:16Z |
| publishDate | 2020 |
| publisher | Springer Science and Business Media LLC |
| record_format | dspace |
| spelling | mit-1721.1/1267822022-10-02T04:29:32Z Mineral protection regulates long-term global preservation of natural organic carbon Hemingway, Jordon Dennis Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences The balance between photosynthetic organic carbon production and respiration controls atmospheric composition and climate1,2. The majority of organic carbon is respired back to carbon dioxide in the biosphere, but a small fraction escapes remineralization and is preserved over geological timescales3. By removing reduced carbon from Earth’s surface, this sequestration process promotes atmospheric oxygen accumulation2 and carbon dioxide removal1. Two major mechanisms have been proposed to explain organic carbon preservation: selective preservation of biochemically unreactive compounds4,5 and protection resulting from interactions with a mineral matrix6,7. Although both mechanisms can operate across a range of environments and timescales, their global relative importance on 1,000-year to 100,000-year timescales remains uncertain4. Here we present a global dataset of the distributions of organic carbon activation energy and corresponding radiocarbon ages in soils, sediments and dissolved organic carbon. We find that activation energy distributions broaden over time in all mineral-containing samples. This result requires increasing bond-strength diversity, consistent with the formation of organo-mineral bonds8 but inconsistent with selective preservation. Radiocarbon ages further reveal that high-energy, mineral-bound organic carbon persists for millennia relative to low-energy, unbound organic carbon. Our results provide globally coherent evidence for the proposed7 importance of mineral protection in promoting organic carbon preservation. We suggest that similar studies of bond-strength diversity in ancient sediments may reveal how and why organic carbon preservation—and thus atmospheric composition and climate—has varied over geological time. 2020-08-25T11:38:18Z 2020-08-25T11:38:18Z 2019-06 2018-11 2020-08-24T16:44:09Z Article http://purl.org/eprint/type/JournalArticle 0028-0836 https://hdl.handle.net/1721.1/126782 Hemingway, Jordon D. et al. “Mineral protection regulates long-term global preservation of natural organic carbon.” Nature, 570, 7760 (June 2019): 228–231 © 2019 The Author(s) en 10.1038/S41586-019-1280-6 Nature Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf Springer Science and Business Media LLC Prof. Rothman via Chris Sherratt |
| spellingShingle | Hemingway, Jordon Dennis Mineral protection regulates long-term global preservation of natural organic carbon |
| title | Mineral protection regulates long-term global preservation of natural organic carbon |
| title_full | Mineral protection regulates long-term global preservation of natural organic carbon |
| title_fullStr | Mineral protection regulates long-term global preservation of natural organic carbon |
| title_full_unstemmed | Mineral protection regulates long-term global preservation of natural organic carbon |
| title_short | Mineral protection regulates long-term global preservation of natural organic carbon |
| title_sort | mineral protection regulates long term global preservation of natural organic carbon |
| url | https://hdl.handle.net/1721.1/126782 |
| work_keys_str_mv | AT hemingwayjordondennis mineralprotectionregulateslongtermglobalpreservationofnaturalorganiccarbon |