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Estuaries and Coasts

, Volume 38, Issue 1, pp 56–71 | Cite as

Historical Reconstruction of Phytoplankton Composition in Estuaries of Fiordland, New Zealand: the Application of Plant Pigment Biomarkers

  • Susanne E. SchüllerEmail author
  • Thomas S. Bianchi
  • Xinxin Li
  • Mead A. Allison
  • Candida Savage
Article

Abstract

Phytoplankton pigments in sediment cores from four New Zealand fjords were quantified to investigate community composition and primary production in this pristine and remote region. Downcore sediment records from Doubtful Sound, Fiordland, were also compared with phytoplankton pigments in sediment traps to investigate pathways of phytodetritus flux from the upper water column to the sediment. Historic primary production was estimated using downcore chlorophyll a (Chl a) and β-carotene as proxies for total algal biomass. Sedimentary Chl a was similar across Fiordland (p = 0.09), but β-carotene was significantly different in Broughton Arm (Kruskal–Wallis p < 0.01). Dominant transformation products of Chl a were steryl chlorin esters and carotenol chlorin esters, indicating the importance of grazing as a sink for phytoplankton in Fiordland. Carotenoids indicative of diatoms and dinoflagellates were recovered in the sedimentary records of Doubtful Sound. Pigment biomarkers were observed in higher quantities in the sediment traps than in the surface sediment. In particular, grazing biomarkers were abundant in the sediment, highlighting the importance of fecal pellet export in phytodetritus preservation. Phytoplankton pigment preservation in Fiordland sediments is good as indicated by little variation in Chl a/pheopigment ratios throughout the cores. This research supports other new work, which has shown that carbon preservation in southern hemisphere fjord ecosystems is more efficient than previously thought.

Keywords

Fjord ecosystem Historic primary productivity Biomarkers Grazing Paleoproxies Pigment degradation 

Notes

Acknowledgments

We would like to thank the captain and crew of the RV Polaris II for support in the field. We are grateful for financial support from UORG and PBRF funds (C.S.), New Zealand International Doctoral Research Scholarship and a University of Otago Publishing Bursary (S.E.S.), and the Chinese Scholarship Council (X.L.). The manuscript benefited from comments by Jun Zhao and two anonymous reviewers.

Supplementary material

12237_2014_9771_Fig8_ESM.jpg (314 kb)
Fig. S1

Chromatogram of sediment analyzed by HPLC analysis from the surface interval (0-2 cm) at Malaspina Reach, Doubtful Sound. Identification of individual peaks was based on retention time and PDA spectra (see Methods). Two unknown peaks are observed, their absorbance spectra are included and their potential identification is indicated within the chromatogram (JPEG 313 kb)

12237_2014_9771_MOESM1_ESM.eps (376 kb)
High resolution image (EPS 376 kb)

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Copyright information

© Coastal and Estuarine Research Federation 2014

Authors and Affiliations

  • Susanne E. Schüller
    • 1
    Email author
  • Thomas S. Bianchi
    • 2
    • 5
  • Xinxin Li
    • 2
    • 6
  • Mead A. Allison
    • 3
    • 7
    • 8
  • Candida Savage
    • 1
    • 4
  1. 1.Department of Marine ScienceUniversity of OtagoDunedinNew Zealand
  2. 2.Department of OceanographyTexas A&M UniversityCollege StationUSA
  3. 3.Institute for Geophysics, Jackson School of GeosciencesUniversity of TexasAustinUSA
  4. 4.Department of Biological Sciences and Marine Research InstituteUniversity of Cape TownRondeboschSouth Africa
  5. 5.Department of Geological SciencesUniversity of FloridaGainesvilleUSA
  6. 6.Geochemical and Environmental Research GroupTexas A&M UniversityCollege StationUSA
  7. 7.The Water Institute of the GulfBaton RougeUSA
  8. 8.Department of Earth & Environmental SciencesTulane UniversityNew OrleansUSA

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