Unexpected release of phosphate and organic carbon to streams linked to declining nitrogen depositions
© 2016 John Wiley & Sons Ltd.
| Veröffentlicht in: | Global change biology. - 1999. - 23(2017), 5 vom: 01. Mai, Seite 1891-1901 |
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| Weitere Verfasser: | , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2017
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| Zugriff auf das übergeordnete Werk: | Global change biology |
| Schlagworte: | Journal Article Meta-Analysis atmospheric deposition carbon cycle nitrogen biogeochemistry organic matter riparian zone streamwater chemistry Ferric Compounds Phosphates mehr... |
| Zusammenfassung: | © 2016 John Wiley & Sons Ltd. Reductions in emissions have successfully led to a regional decline in atmospheric nitrogen depositions over the past 20 years. By analyzing long-term data from 110 mountainous streams draining into German drinking water reservoirs, nitrate concentrations indeed declined in the majority of catchments. Furthermore, our meta-analysis indicates that the declining nitrate levels are linked to the release of dissolved iron to streams likely due to a reductive dissolution of iron(III) minerals in riparian wetland soils. This dissolution process mobilized adsorbed compounds, such as phosphate, dissolved organic carbon and arsenic, resulting in concentration increases in the streams and higher inputs to receiving drinking water reservoirs. Reductive mobilization was most significant in catchments with stream nitrate concentrations <6 mg L-1 . Here, nitrate, as a competing electron acceptor, was too low in concentration to inhibit microbial iron(III) reduction. Consequently, observed trends were strongest in forested catchments, where nitrate concentrations were unaffected by agricultural and urban sources and which were therefore sensitive to reductions of atmospheric nitrogen depositions. We conclude that there is strong evidence that the decline in nitrogen deposition toward pre-industrial conditions lowers the redox buffer in riparian soils, destabilizing formerly fixed problematic compounds, and results in serious implications for water quality |
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| Beschreibung: | Date Completed 23.10.2017 Date Revised 02.12.2018 published: Print-Electronic CommentIn: Glob Chang Biol. 2017 Jul;23 (7):2535-2536. - PMID 28192638 Citation Status MEDLINE |
| ISSN: | 1365-2486 |
| DOI: | 10.1111/gcb.13498 |