Journal article
Tracing nitrate sources using the isotopic composition of skeletal-bound organic matter from the calcareous green algae Halimeda
Coral Reefs, Vol.37(4), pp.1003-1011
03/11/2018
Metrics
7 Record Views
UN Sustainable Development Goals (SDGs)
This output has contributed to the advancement of the following goals:
Source: InCites
Abstract
The nitrogen (N) isotopic composition (δ15N) of water column nitrate (NO3−) reveals important information about the source(s) of N, and/or the transformation processes occurring during N transport, to a particular environment. However the physical collection of samples for δ15N–NO3− determination can be logistically challenging and does not address questions about historical δ15N–NO3−. Here we adapt the persulphate/denitrifier protocol, previously developed for scleractinian corals, to analyse the δ15N of organic material in the skeletons of the calcareous macroalgae Halimeda (hereafter referred to as δ15N-SOM). Using the newly established protocol, we show that the Halimeda δ15N-SOM can be used as a proxy for the δ15N of water column NO3−. Based on aquarium and field measurements we show that the maximum offset between the Halimeda δ15N-SOM and the δ15N of water column NO3−, as a result of fractionation during uptake, is 1‰. However this was only tested at low NO3− concentrations (< 10 μmol L−1). Our results demonstrate that in low-nutrient environments, Halimeda skeletal material, including historical material obtained from sediment cores, can provide a reliable proxy record of δ15N–NO3− at the base of the food web. This technique holds much promise for reconstructing spatial and temporal patterns of N supply to coral reef systems worldwide.
Details
- Title
- Tracing nitrate sources using the isotopic composition of skeletal-bound organic matter from the calcareous green algae Halimeda
- Creators
- Drik V. Erler - Southern Cross UniversityLuke Nothdurft - Queensland University of TechnologyMardi McNeil - Queensland University of TechnologyCharly Moras - Southern Cross University
- Publication Details
- Coral Reefs, Vol.37(4), pp.1003-1011
- Publisher
- Springer; Berlin/Heidelberg
- Grant note
- DP170100734 / Australian Research Council (http://dx.doi.org/10.13039/501100000923) This work was supported by an Australian Research Council Discovery Project grant (DP170100734). We would like to thank Sven Uthicke from the Australian Institute of Marine Science for the supply of Halimeda specimens and water samples. The SEM data reported in this paper were obtained at the Central Analytical Research Facility (CARF) operated by the Institute for Future Environments (QUT). Access to CARF is supported by funding from the Science and Engineering Faculty (QUT).
- Identifiers
- 991012926960802368
- Copyright
- © Springer-Verlag GmbH Germany, part of Springer Nature 2018
- Academic Unit
- National Centre for Flood Research; Faculty of Science and Engineering; Science; Centre for Coastal Biogeochemistry
- Language
- English
- Resource Type
- Journal article