Variability in nitrogen stable isotope ratios of macroalgae : consequences for the identification of nitrogen sources

© 2014 Phycological Society of America.

Bibliographische Detailangaben
Veröffentlicht in:Journal of phycology. - 1966. - 51(2015), 1 vom: 12. Feb., Seite 46-65
1. Verfasser: Ochoa-Izaguirre, María Julia (VerfasserIn)
Weitere Verfasser: Soto-Jiménez, Martín F
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2015
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
Beschreibung
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
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