Variability in nitrogen stable isotope ratios of macroalgae : consequences for the identification of nitrogen sources
© 2014 Phycological Society of America.
Veröffentlicht in: | Journal of phycology. - 1966. - 51(2015), 1 vom: 12. Feb., Seite 46-65 |
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Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2015
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Zugriff auf das übergeordnete Werk: | Journal of phycology |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Eutrophication biogeochemical processes isotopic fractionation macroalgal metabolism δ15N-Macroalgal |
Zusammenfassung: | © 2014 Phycological Society of America. In our research, we collected and analyzed numerous macroalgal specimens (738) for isotopic analysis sampled over a year at monthly intervals across 20 sites within the Urías lagoon complex, a typical subtropical coastal ecosystem located in the Gulf of California. We quantified and characterized (chemically and isotopically) the N loads received by Urías throughout a year. We studied the spatial-temporal variation of the chemical forms and isotopic signals of the available N in the water column, and we monitored in situ different environmental variables and other hydrodynamic parameters. Multiple N sources (e.g., atmospheric, sewage, seafood processing, agriculture and aquaculture effluents) and biogeochemical reactions related to the N cycle (e.g., ammonia volatilization, nitrification and denitrification) co-occurring across the ecosystem, result in a mixture of chemical species and isotopic compositions of available N in the water column. Increased variability was observed in the δ(15) N values of macroalgae (0.41‰-22.67‰). Based on our results, the variation in δ(15) N was best explained by spatio-temporal changes in available N and not necessarily related to the N sources. The variability was also explained by the differences in macroalgal biology among functional groups, species and/or individuals. Although the δ(15) N-macroalgae technique was a useful tool to identify N sources, its application in coastal ecosystems receiving multiple N sources, with changing environmental conditions influencing biogeochemical processes, and high diversity of ephemeral macroalgal species, could be less sensitive and have less predictive power |
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Beschreibung: | Date Completed 26.07.2016 Date Revised 18.03.2016 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1529-8817 |
DOI: | 10.1111/jpy.12250 |