Table of Contents

• Coverage
• Dataset Description
• Data Files
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

This is from the cruise report (see LGM1110 deployment page for link) and particulary pertains to the Fluorescence data that were collected:

"Preliminary CTD Results: A total of 20 CTD stations were occupied and sampled during the cruise. Hydrographic data were collected in all sampling regions of the study. Casts were sent to the shallower of 1,000 m or 5-10 m above the bottom. The primary fluorometer was mis-calibrated (had the wrong scale factor in the calibration/processing file), so fluorescence data from the first four (or five) stations (Stns #22, #7, #8, #11) had to be re-processed with the correct scaling factor. Examination of the *.cnv file showed which casts had the miscalibrated data, as the max reading for fluorescence was ~ 0.05 mg/m3. For nearly every other station, maximum fluorescence readings were > 1.0 mg/m3. A secondary fluorometer was added to the CTD rosette between Stns #11 and #12, which verified that the issue was with the scale factor in the CTD processing software."

The data that are served have warnings about fluorescence numbers in the headers of the casts at Stations 22, 7, 8 and 11.

Variables that were part of the data that have been rendered invisible from the data online are: Elapsed time in seconds, modulo error count (always zero), and nbin (number of scans per bin). Those numbers are available upon request.

IEDA has published a DOI for another version of this dataset: 'Bucklin, A., (2015). 'Calibrated Hydrographic Data from Drake Passage acquired with a CTD during the Laurence M. Gould expedition LMG1110 (2011). doi: 10.1594/IEDA/318146.

The Antarctic salp, Salpa thompsoni, is an increasingly important player in the vulnerable Antarctic Peninsula pelagic ecosystem. Observations of high abundance of Salpa thompsoni during the summer in the Southern Ocean suggest that this species is capable of rapid somatic and population growth, and frequently forms dense blooms under favorable environmental conditions. The proposed research will examine genome-wide patterns of gene expression, target gene expression levels, and patterns of population genetic diversity and structure of the target salp species. Our preliminary results and data analysis have provided a promising basis for transcriptomic studies of S. thompsoni in the Southern Ocean. The proposed next steps in our genomic/transcriptomic analysis of Salpa thompsoni are: 1) completion of a reference transcriptome as a basis for genome-wide analysis of gene expression; 2) whole transcriptome shotgun sequencing (RNA-Seq) analysis to characterize gene expression in relation to individual characteristics and environmental conditions; 3) quantitative real-time PCR (qRT-PCR) characterization and validation of gene expression for 10-20 top differentially-expressed genes; and 4) detection of strand-specific allelic variation at SNP (Single Nucleotide Polymorphic) sites to analyze clonal diversity and population genetic diversity and structure. We hypothesize that: 1) deep analysis of the Salpa thompsoni transcriptome will reveal significant associations among selected set of differentially-expressed genes and critical life history stages and events (e.g., ontogenetic maturation, sexual reproduction, senescence) of the salp; and 2) the species will show variable levels of clonal diversity and significant genetic differentiation among salp populations in different regions of the Southern Ocean. Samples will be obtained from research cruises during 2011-2013 in diverse regions of the Southern Ocean; dedicated sample and data collection will be carried out during a cruise of the R/V LM GOULD (LMG11-10) to the Western Antarctic Peninsula region in November, 2011. The significance of this effort lies in new understanding of the molecular processes underlying the complex life history and population dynamics of S. thompsoni in relation to the Antarctic pelagic ecosystem and extreme and variable environmental conditions of the Southern Ocean.

Most of the data from this project are available from the Marine Geoscience Data System (MGDS), part of IEDA and is available at http://www.marine-geo.org/tools/search/Files.php?data_set_uid=18148.