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Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N
Terrestrial agricultural activities strongly influence riverine nitrogen (N) dynamics, which is reflected in the δ(15)N of riverine consumer tissues. However, processes within aquatic ecosystems also influence consumer tissue δ(15)N. As aquatic processes become more important terrestrial inputs may...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2013
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3729966/ https://www.ncbi.nlm.nih.gov/pubmed/23935980 http://dx.doi.org/10.1371/journal.pone.0069313 |
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author | Larson, James H. Richardson, William B. Vallazza, Jon M. Nelson, John C. |
author_facet | Larson, James H. Richardson, William B. Vallazza, Jon M. Nelson, John C. |
author_sort | Larson, James H. |
collection | PubMed |
description | Terrestrial agricultural activities strongly influence riverine nitrogen (N) dynamics, which is reflected in the δ(15)N of riverine consumer tissues. However, processes within aquatic ecosystems also influence consumer tissue δ(15)N. As aquatic processes become more important terrestrial inputs may become a weaker predictor of consumer tissue δ(15)N. In a previous study, this terrestrial-consumer tissue δ(15)N connection was very strong at river sites, but was disrupted by processes occurring in rivermouths (the ‘rivermouth effect’). This suggested that watershed indicators of N loading might be accurate in riverine settings, but could be inaccurate when considering N loading to the nearshore of large lakes and oceans. In this study, the rivermouth effect was examined on twenty-five sites spread across the Laurentian Great Lakes. Relationships between agriculture and consumer tissue δ(15)N occurred in both upstream rivers and at the outlets where rivermouths connect to the nearshore zone, but agriculture explained less variation and had a weaker effect at the outlet. These results suggest that rivermouths may sometimes be significant sources or sinks of N, which would cause N loading estimates to the nearshore zone that are typically made at discharge gages further upstream to be inaccurate. Identifying definitively the controls over the rivermouth effect on N loading (and other nutrients) will require integration of biogeochemical and hydrologic models. |
format | Online Article Text |
id | pubmed-3729966 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2013 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-37299662013-08-09 Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N Larson, James H. Richardson, William B. Vallazza, Jon M. Nelson, John C. PLoS One Research Article Terrestrial agricultural activities strongly influence riverine nitrogen (N) dynamics, which is reflected in the δ(15)N of riverine consumer tissues. However, processes within aquatic ecosystems also influence consumer tissue δ(15)N. As aquatic processes become more important terrestrial inputs may become a weaker predictor of consumer tissue δ(15)N. In a previous study, this terrestrial-consumer tissue δ(15)N connection was very strong at river sites, but was disrupted by processes occurring in rivermouths (the ‘rivermouth effect’). This suggested that watershed indicators of N loading might be accurate in riverine settings, but could be inaccurate when considering N loading to the nearshore of large lakes and oceans. In this study, the rivermouth effect was examined on twenty-five sites spread across the Laurentian Great Lakes. Relationships between agriculture and consumer tissue δ(15)N occurred in both upstream rivers and at the outlets where rivermouths connect to the nearshore zone, but agriculture explained less variation and had a weaker effect at the outlet. These results suggest that rivermouths may sometimes be significant sources or sinks of N, which would cause N loading estimates to the nearshore zone that are typically made at discharge gages further upstream to be inaccurate. Identifying definitively the controls over the rivermouth effect on N loading (and other nutrients) will require integration of biogeochemical and hydrologic models. Public Library of Science 2013-07-31 /pmc/articles/PMC3729966/ /pubmed/23935980 http://dx.doi.org/10.1371/journal.pone.0069313 Text en https://creativecommons.org/publicdomain/zero/1.0/ This is an open-access article distributed under the terms of the Creative Commons Public Domain declaration, which stipulates that, once placed in the public domain, this work may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. |
spellingShingle | Research Article Larson, James H. Richardson, William B. Vallazza, Jon M. Nelson, John C. Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N |
title | Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N |
title_full | Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N |
title_fullStr | Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N |
title_full_unstemmed | Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N |
title_short | Rivermouth Alteration of Agricultural Impacts on Consumer Tissue δ(15)N |
title_sort | rivermouth alteration of agricultural impacts on consumer tissue δ(15)n |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3729966/ https://www.ncbi.nlm.nih.gov/pubmed/23935980 http://dx.doi.org/10.1371/journal.pone.0069313 |
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