This data set was collected from a ocean acidification minicosm experiment performed at Davis Station, Antarctica during the 2014/15 summer season. It includes: - description of methods for all data collection and analyses. - flow cytometry counts; autotrophic cells, heterotrophic nanoflagellates, and prokaryotes

This data set was collected from two minicosm experiments conducted at Davis Station, Antarctica. 1. Variance experiment - 2013/14 summer season 2. Ocean acidification experiment - 2014/15 summer season It includes: - description of methods for all data collection and analyses. - environmental data logged throughout the experiment; nutrients, temperature, light climate. - flow cytometry counts; autotrophic cells, heterotrophic nanoflagellates, and prokaryotes. - FlowCam counts; individual phytoplankton species data. - microscopy counts; individual phytoplankton species data.

Metadata record for data from ASAC Project 288 See the link below for public details on this project. From the abstract of the referenced paper: In January-February 1991, in Prydz Bay, phytoplankton bloom was evident in the inner shelf area with the dominant diatoms being represented mainly by pennate species of the Nitzschia-Fragilariopsis group. Dinoflagellates and naked flagellates were most abundant in the centre of the bay; however, larger heterotrophic species prevailed at the southern stations. Cell carbon values (average 317 micro grams per litre; range 92-1048 micrograms per litre) found in the bloom in the south were chiefly due to pennate diatoms and larger heterotrophic dinoflagellates. Much lower carbon values (average 51 micro grams per litre; range 7-147 micro grams per litre) in the outer shelf region were mainliy contributed by large centric diatoms (70-110 micro metres) and small dinoflagellates (5-25 micro metres). Wide ranges of algal cell sizes were observed in both southern and northern communities; the overlapping of sizes of diatoms and flagellates, the latter containing heterotrophs, suggested complex trophic relationships within the plankton and an enhanced heterotrophic activity in the south. North-to-south variations in surface delta 13 C of suspended particulate organic matter (SPOM), (range -31.85 to -20.12 parts per thousand) were directly related to the concentration of particulate matter: this suggested the effect of biomass, and thus of dissolved CO2 limitation on carbon fractionation. Three types of species assemblages were distinguished, corresponding to different narrow ranges of delta 13 C values (-20.12 to -22.37 parts per thousand; -24.50 to -26.65 parts per thousand; -29.73 to -31.85 parts per thousand); dominant species within each assemblage are the likely major determinants of the carbon isotopic composition and variation of SPOM. Pennate diatoms, such as Nitzschia curta and N. subcurvata appear to have made the major imprint on the highest delta 13 C values. Phaeocystis, naked flagellates, autotrophic dinoflagellates and centric diatoms are likely to have caused the lower delta 13 C values of SPOM. It appears that variations in both biomass concentration and in phytoplankton species composition have contributed to the carbon isotopic values of SPOM in Prydz Bay.

Some scanning electron microscope images were taken of dinoflagellates sampled as part of this project. A catalogue of the images taken is provided as part of the download file at the provided URL. The images are currently held by the Electron Microscope Unit of the Australian Antarctic Division, but have not yet been entered into their electron microscope database (as at the 30th of April, 2004). From the abstracts of the referenced paper: The abundance and biomass of ciliates, dinoflagellates and heterotrophic and phototrophic nanoflagellates were determined at three sites along an ice-covered Antarctic fjord between January and November 1993. The water column showed little in the way of temperature and salinity gradients during the study period. In general, the protozooplankton exhibited a seasonal variation which closely mirrored that of chlorophyll a and bacterioplankton. The fjord mouth, which was affected by the greatest marine influences, consistently had the highest densities of ciliates and the most diverse community, with up to 18 species during the sampling period. Small aloricate ciliates were present throughout the year with Strobilidium spp. being dominant during the winter. Larger loricate and aloricate ciliates became more prominent during January and November, along with the autotrophic ciliate Mesodimium rubrun and two mixotrophic species (Strombidium wulffi and a type resembling Tontonia) suggesting evidence of species successions. Data on dinoflagellates were less extensive, but these protists showed greatest species diversity in the middle reaches of the fjord. A total of 13 species of dinoflagellate were recorded. Ciliates made a significant contribution to the biomass of the microbial community in summer, particularly in the middle and at the seaward end of the fjord. In winter, heterotrophic flagellates (HNAN) and phototrophic nanoflagellates (PNAN) were the dominant component of protistan biomass. In terms of percentage contribution to the microbial carbon pool, bacteria dominated during winter and spring. To the authors' knowledge, this is the first seasonal study of an Antarctic fjord. The Ellis Fjord is very unproductive compared to lower latitude systems, and supports low biomass of phytoplankton and microbial plankton during most of the year. This relates to severe climatic and seasonal conditions, and the lack of allochthonous carbon inputs to the system. Thus, high latitude estuaries may differ significantly from lower latitude systems, which generally rank among the most productive aquatic systems in the world. The fields in this dataset are: EMU Image Number Fiona Scott Image Number Species SEM Stub Number Location Collector

These data contain results from grazing dilution experiments conducted during BROKE-West. Experiments were conducted at 22 locations on the BROKE-West transect. Data are presented in an excel spreadsheet containing sample collection information (longitude, latitude, UTC date and time, depth), experiment details (incubation time, dilution series), experiment results (chlorophyll a, bacterial concentrations, heterotrophic flagellate concentrations, phytoplankton concentrations, microzooplankton concentrations, geometric mean predator density, phytoplankton growth rates, microzooplankton grazing rates for bacteria and phytoplankton, bacterial growth rates). This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679).

This dataset contains results from the Second International BIOMASS Experiment II (SIBEX II) cruise of the Nella Dan, taken in January 1985. This cruise was the fourth cruise in a series of six. Phytoplankton samples were taken off Antarctica in the Australian sector (Mawson to Davis region) and Prydz Bay in January 1985. Taxonomic identity, distribution and abundance data were obtained, together with an extensive range of pigment analysis, using high performance liquid chromatography (HPLC). Over 60 pigments were analysed (only the major ones are listed here). The major phytoplankton investigated were diatoms, dinoflagellates and flagellates. This dataset is a subset of the full cruise. An excel spreadsheet containing the full pigment analysis obtained from the cruise is available for download from the URL given below. The spreadsheet is a digital version of the data presented in ANARE Research Notes 58, which was a report written based on this dataset. There are three worksheets to the spreadsheet: 1) Abbrev. - details the abbreviations used in worksheets 2 and 3. 2) Table 3 - Table 3 data entered from ANARE Research Notes 58. 3) Transposed Table 3 - The same data as worksheet 2, but arranged differently. A pdf copy of ANARE Research Notes 58 is also available for download at the URL given below. A paper written in 2006 about pigments in microalgae, which provides some up-to-date explanations about pigmentation, is also available for download, but owing to copyright restrictions, is only available for download by Australian Antarctic Division personnel. The fields in this dataset are: Date Time (GMT) Latitude Longitude Depth (metres) Pigment concentration (nanograms per litre) chlorophyllide a chlorophyll c methyl chlorophyllide a phaeophorbide a peridinin 19'-butanoyloxyfucoxanthin fucoxanthin 19'-hexanoyloxyfucoxanthin Neoxanthin Prasinoxanthin Violaxanthin Diadinoxanthin Alloxanthin diatoxanthin Zeaxanthin Canthaxanthin Unknown Chlorophyll b Chlorophyll a allomer Chlorophyll a Chlorophyll a epimer Phaeophytin a derivative Phaeophytin b Phaeophytin a Chlorophyll a total % Degradation Pigment total This work was completed as part of ASAC project 40 (ASAC_40).

The BROKE-West survey was conducted on voyage 3 of the Aurora Australis during the 2005-3006 season. It was intended to be a comprehensive biological and oceanographic survey of the region between 30 degrees and 80 degrees east. A number of metadata records providing more detail about aspects of the voyage are linked off this metadata record. Copies of the public summaries from the underlying ASAC projects of the voyage are below: A planned acoustic biomass survey for krill in CCAMLR Division 58.4.2 (South West Indian Ocean) in January-March 2006 will produce the data for a revised catch limit on the krill fishery. The survey will utilise a standardised design as adopted in previous biomass surveys in the CCAMLR Area and will consist of 11 parallel transects between 30 degrees and 80 degrees east. A full suite of ecological measurements will be conducted: physical and chemical oceanography, primary productivity, microbial diversity, zooplankton distribution and abundance, krill distribution, abundance and demographics, fish distribution, abundance and genetics, and seabird and cetacean distribution. The three-dimensional ocean circulation from the 30 to 80 degrees E and 200nm from Antarctica is being studied through the use of direct measurements of velocity, temperature, salinity, oxygen, nutrients , chloro-flourocarbons, dissolved inorganic carbon and bio-geochemical cycles. This multi-disciplinary experiment (see also project 2655) will determine the circulation of the region, its relation to bio-geochemical cycles, carbon cycle and ecosystems. The temperature and salinity data will also be used to test for long term trends that could be related to climate change. This work was completed as part of ASAC projects 2655 and 2679 (ASAC_2655, ASAC_2679). A pdf copy of the proposed voyage track is available for download from the provided URL. Two csv files detailing the locations (latitudes and longitudes), plus times and dates (UTC) of the trawl and ctd stations on the BROKE-West voyage are available for download from the provided URL. Additional comments (where applicable) about each station are also provided.

Preliminary Metadata record for data expected from ASAC Project 1343 See the link below for public details on this project. Comparative study of the processes controlling carbon export in Southern Ocean environments characterised by a different hydrodynamical and ecological functioning. Work on this project was carried out on Voyage 3 of the Aurora Australis (CLIVAR) of the 2001 and 2002 season. Work at sea target sampling sites were the 8 'particle stations' along the CLIVAR SR3 repeat transect: the SAZ at 47 degrees and 49 degrees S; the SAF at 51 degrees S; the PFZ at 54 degrees S; the IPFZ at 57 degrees S; the SPZ at 59 degrees and 61 degrees S; the SACCF at 63 degrees S and the SSIZ at 64 degrees S. Some of these (64 degrees, 61 degrees and 51 degrees S) were sampled again on the way back to assess temporal evolution. All proxy studies (new production; Ba; delta30Si; 234Th-deficit) were done at each particle station but not necessarily on the same CTD casts. New production assessment Surface water (at 5, 25, 50 and 70m) was sampled with the CTD rosette at all particle stations. Different aliquots of 1L seawater were spiked with 15N-nitrate, 15N-ammonium or 15N-urea. All samples were spiked with 13C-bicarbonate; the latter in order to assess net primary production rates. Incubations (12 H) were done in a thermo stated algal cabinet, using appropriate neutral density screens for samples from depths below 5m. The samples were submitted to a constant light flux of 0.7x10power16 quanta/cm2/sec. Furthermore, samples from 5m depth were amended with increasing doses of ammonium (+0.1 micro M; +0.25 micro M; +0.5 micro M and +1 micro M) having natural 15N/14N abundance to assess susceptibility of N-uptake (ammonium, nitrate, urea) to ammonium. Similar experiments were run for three iron amended and control cultures in collaboration with Pete Sedwick, Dave Hutchins and Phil Boyd. Analysis of ammonium related to the incubation work was done on board by colorimetry. As a side product we obtained ammonium profiles at all particle stations and also six shallow CTD's in the southern part of the transect (greater than 61 degrees S). Suspended particle sampling for trace element analysis and isotopic composition of Si For biogenic-Ba was also carried out. Typically 14 depths were sampled between the surface and 1000m. On board filtration was performed on Nuclepore membranes. These were dried (60 degrees C) and stored for analysis in the shore-based lab. Occasionally, we also sampled large particles - size fractions (greater than 70 micro m and 20 less than 70 micro m) - from the upper 150m for Ba, using the bow pump system of Tom Trull. Ba and Sr incubations on large settling particles sampled with the Snatcher were also performed at 5 particle stations. For delta30Si, all 24 depths of the deep CTD casts at the particle stations 1 to 8 were sampled. Filtered seawater and suspended matter filtered on Nuclepore membranes (dried at 60 degrees C) were saved for later analysis in the home based laboratory. 234Th work - we refer to the report by Ken Buesseler for the major part of this work. In addition we performed some work using the 'Snatcher' Large Volume sampler and sedimentation column. Total 234Th deficit and 234Th activity on particles and solution was assessed at T0 and T4 H after return of the sampling device on board, in an attempt to construct the 234Th mass balance and eventually get at the settling speed (and flux) of 234Th carrying particles. These analyses went together with flow cytometry analyses (collaboration with Clive Crossley) to check for sedimentation by (fluorescent) particles and also with POC and biogenic silica in order to determine the elemental ratios of suspended and sinking particles. Flow cytometer results did not indicate there was significant sedimentation of life cells going on at this time of the year. Dissolved Ba Seawater samples were taken at all depths sampled by deep CTD's during the southward transect. Samples were acidified and kept for later analysis of dissolved barium by isotope dilution ICP-MS. Comparison of the dissolved Ba distribution along the transect with the one reconstructed through a multiple end-member mixing model will help understanding of the relative contribution of in-situ processes (uptake, dissolution) versus conservative mixing, thus improving our understanding of the oceanic Ba biogeochemistry. Analysis New production. Isotope ratio analysis of the 15N and 13C spiked natural plankton samples will be conducted in the home lab., using emission spectrometry and mass spectrometry. Mass balance calculations will allow assessing relative importance of new production as well as the fraction of new production that is in the particulate form and represents the potential for export. Ba and trace elements. Suspended matter samples will be acid digested (HNO3, HCl, HF) and analysed per ICP-MS and ICP-AES for contents of Ba, Ca, Sr, Al, Fe, Mn, Th, U, REE, Ti. The vertical concentration profiles will inform on the latitudinal and temporal variability of the biogeochemical control processes between SAZ, PFZ, ACC and SSIZ subsystems. For the sites with sediment trap deployments, particulate trace element distributions in the water column will be compared with trace element composition of fast settling particles intercepted by the traps. Ba-uptake / barite formation. Isotope ratio analysis (135Ba/138Ba; 86Sr/87Sr) of suspended matter incubated after spiking with 135Ba and 86Sr will be analysed by ICP-MS to investigate on the barite formation process. Abundance and type of barite crystals will be studied by SEM-EMP (mapping + photographs). delta30Si, In the home based lab. particle samples will be extracted using base (NaOH). Silicates in filtered seawater will be precipitated and analysed using a multi collector ICP-sectorial Mass Spectrometer (MC-ICP-MS) once this new method is set up. 234Th. Total, particulate and dissolved 234Th measurements were performed on board using low beta counters. Background (after 6 months decay) and chemical yields will be measured at Ken Buesseler's lab (WHOI, USA), using beta counters and ICP-MS respectively. The worksheets contained in the excel spreadsheet are: Phyo biomass New production and cell counts Particulate barium Dissolved barium d29Si isotope signature of dissolved silicic acid The fields in this dataset are: Carbon Seawater CLIVAR temperature pressure salinity depth barium latitude longitude oxygen silicate phophate nitrate flagellates diatoms picoplankton plankton urea ammonia coccolithophores