Temporal variation of seston biomarkers within the Humboldt Current System off northern Chile (21°S): First simultaneous records on fatty acids, n-alkanes and glycerol-dialkyl-glycerol-tetraethers (GDGT)

Sergio Rossi, Enrique Isla, Susanne Fietz, Alfredo Martínez-Garcia, Elisabet Sañé, Núria Teixidò

Research output: Contribution to journalArticleResearchpeer-review

3 Citations (Scopus)

Abstract

Proportions and concentrations of seston fatty acids, n-alkanes and glycerol dialkyl glycerol tetraethers (GDGTs) were used to assess potential differences in the phytoplankton composition and food quality in the Humboldt Current System (winter 2006, summer 2007 and winter 2007) in surface, oxycline, intermediate and bottom water layers. The zone below the intermediate depth was poorer in fatty acids (minimum 15 - maximum 117 μg fatty acids L-1) than the upper water layers (minimum 36 - maximum 210 μg fatty acids L-1), which were richer in saturated fatty acids (SAFA, up to 80%), but had a similar proportion of bacterial markers (13:0.15 iso/anteiso, 15:0, and 17:0 sum up to 67%). Isoprenoid GDGTs showed the presence of archaea in the different water layers. All the water layers also showed long chained fatty acids (22:0, 24:1 and 26:0), which can be considered to be of terrestrial origin. The n-alkanes were used to confirm this potential terrestrial origin through the Carbon Preference Index (CPI), which was always above the 4.3 due to the significant presence of c25, c27, and c31. Both lipid markers were positively related (R2=0.64, p<0.05). In winter 2007, no clear phytoplankton dominance was detected through lipid markers, and there was a clear dominance of poor quality material along the water column coinciding with the development of La Niña 2007. © 2012 Copyright Taylor and Francis Group, LLC.
Original languageEnglish
Pages (from-to)17-40
JournalAdvances in Oceanography and Limnology
Volume3
Issue number1
DOIs
Publication statusPublished - 1 Jan 2012

Keywords

  • bacterial biomarkers
  • Carbon Preference Index
  • fatty acids
  • glycerol dialkyl glycerol tetraethers
  • Humboldt Current System
  • La Niña
  • n-alkanes
  • oxycline
  • upwelling

Fingerprint Dive into the research topics of 'Temporal variation of seston biomarkers within the Humboldt Current System off northern Chile (21°S): First simultaneous records on fatty acids, n-alkanes and glycerol-dialkyl-glycerol-tetraethers (GDGT)'. Together they form a unique fingerprint.

Cite this