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The following methods text is primarily extracted from a manuscript submitted for publication, with only minor modifications, the related data set includes a subset of samples, collected from Green Gorge and Bauer Bay, which are additional to that described in the publication. Study Sites Two fuel spill sites were included in this study, Main Power House (MPH) and Fuel Farm (FF), both located on the Macquarie Island isthmus at the northern end of the island. Both sites are within the vicinity of the islands research station (see map provided). The spills are in close proximity to fuel tanks, buildings, roads and other station infrastructure, they experience foot and vehicle traffic, and are thus considerably disturbed habitats. The MPH site is the location of the diesel generators which provide the stations power supply. The FF site contains a series of storage tanks that hold the stations fuel supplies. The habitats of the two sites differ; the FF site is on an elevated headland, is well vegetated and the substrate is largely fill material, while the MPH site is largely devoid of vegetation cover and has a substrate of unconsolidated coarse sand. Field Survey Sampling occurred between 23 January and 13 March 2008 in conjunction with a larger soil survey conducted by the Australian Antarctic Division to delineate the extent of contamination at the spill sites prior to site remediation. Thirty-nine pairs of intact soil cores (75 mm diameter, 70 mm depth) were collected from the Macquarie Island isthmus area. This included 15 from within each of the two fuel spill sites (FF and MPH) and nine away from the spill areas (see map provided). Twelve additional samples were also collected from down-island sites (six each at Green Gorge and Bauer Bay), well away from the influence of the station. Samples collected away from the spill sites were from ecologically comparable habitat to the spill sites; in terms of level and type of disturbance and factors such as vegetation cover, aspect, elevation and soil type. Sample locations within the spill sites covered a range of contaminant levels, including the estimated spill hot spots and spanning out to include clean zones beyond spill-impacted areas. Actual contaminant concentrations were determined after sampling. The at-depth excavations of the 30 samples collected from within the MPH and FF sites enabled measurement of fuel concentrations and other soil chemistry parameters (as per Snape et al. 2010, updated 2014) throughout the soil profile. Soil chemistry for the nine samples collected away from the spill sites were analysed for surface samples only. Invertebrates were extracted from soil cores using Tullgren funnels (light globe providing heat source) immediately following field collection. Extracted invertebrates were collected into 70 mL specimen jars and stored in 70% ethanol. Taxa were ordinal sorted and springtails separated and identified to species level where taxonomic certainty allowed, following Greenslade (2006). Three morphospeices were identified to genus only: 1. Lepidocyrtus sp. is lignorum group nr violaceus Geoffroy, 2. Sminthurides sp. is cf. malmgreni grp Tullberg and 3. Tullbergia sp. includes T. bisetosa Borner and T. templei Wise, with T. bisetosa known to be the more abundant of the two (Mooney 2013). Matched cores were analysed for a range of soil chemical parameters as described in Snape et al. (2010, updated 2014): total petroleum hydrocarbons (TPH) using Gas Chromatography with Flame Ionisation Detector (GC-FID); soil moisture by gravimetric methods; pH and conductivity of water extracts; total organic carbon via mass loss on ignition; and nutrient concentrations (nitrate, nitrite, ammonium, fluoride, bromide, chloride, sulphate and phosphate; using ion chromotography) for water and KCl extracts. Measures of TPH are for range C9-36 and are expressed in mg/kg on a dry weight basis. At each sample location physical environmental variables were assessed: 1. Vegetation percent cover over the surface of the soil cores and 2. Geographic location (latitude, longitude and elevation) measured using a Trimble ProXH GPS receiver coupled to a Trimble Zephyr antenna and differentially corrected with Trimble Pathfinder Office. Fuel plume modelling shown in the map provided was performed in ArcGIS, v10.1, with Xtools Pro extension for generation of surface rasters. Soil TPH data collected up to 2014 was included (with fresh fuel spill signatures after 2007 removed). Null values were used around the perimeter to minimise edge effects. Max TPH values occurred, on average, at 0.8 m below surface. References Snape, Ian, Stark, Scott Charles, Powell, Shane, Ferguson, Susan, Palmer, Anne, Wasley, Jane and Hince, Greg (2010, updated 2014) Characteristics of soil collected on Macquarie Island in 2008. Australian Antarctic Data Centre - doi:http://dx.doi.org/10.4225/15/54190EE461BB8
The effect of pH, temperature and sperm concentration on the fertilisation of Sterechinus neumayeri was investigated. Adult Sterechinus neumayeri were collected from Ellis Fjord Narrows between December and January 2011-12 and held in the Ecotox Field Aquarium Module until used. Between 3-4 male and female individuals were spawned using 0.5M KCl and gametes were collected separately before being fertilised in treatment. The data set shows the percentage of fertilised and non-fertilised eggs of Sterechinus neumayeri scored at 20h post-fertilisation. Eggs were fertilised in various combinations of pH, temperature and sperm concentration treatments (pH: 8.0 (Control), 7.8 and 7.6; Temperature: 1 degrees C (Control), 3 degrees C and 5 degrees C; Sperm concentration (sperm:egg ratio): 1000:1 (Control), 750:1, 250: 1, 50:1 and 5:1). At 20h post fertilisation, 5 ml aliquot was removed from fertilisation vials and eggs were counted and determined if they were fertilised or not. Seawater parameters of treatments were measured at the start and end of the experiment. Detailed information of the spreadsheets are as follows: Seawater Parameters column headings: Temperature - measured in degrees C , shows the temperature treatments used pH - shows the pH levels used Subheading pH - pH level measured for the day using NIST certified buffers Subheading MV - pH level measured for the day in millivolts Subheading Total pH - total pH level in seawater obtained from MV measurements Subheading Temp - temperature of seawater measured for the day 1 deg C column headings: Experiment - number of experiments pH - shows the pH for each treatment Sperm Concentration - shows the sperm concentration used for each treatment in a egg:sperm ratio Rep - shows the number of replicates per experiment Unfertilised eggs - eggs without visible fertilisation envelope and no cleavage after 20h Fertilised eggs - eggs with visible fertilisation envelope and/or cleavage after 20h Fertilised deformed eggs - eggs with visible fertilisation envelope but deformed Total eggs - total eggs scored (whether fertilised or unfertilised) % Fertilised - fertilised eggs (deformed and non-deformed)/Total eggs 3 deg C and 5 deg C have the same column headings as 1 deg C. AAS3134 Abatus sp Growth Experiment Davis 2011-12: The effect of pH and temperature on the growth rate of juvenile Abatus ingens and Abatus shackletoni were investigated. Adult Abatus were collected off Airport Beach in waters 4-5m depth. Data set shows the growth rate of juveniles of Abatus ingens and Abatus shackletoni after a 4-week exposure to various combinations of pH and temperature. Juveniles of each species was removed from maternal pouches and photographed on the oral side before being exposed to combinations of pH (8.0 (Control), 7.8 and 7.6) and temperature (-1 degrees C (Control) and 1 degrees C) levels. They were incubated in treatments for 4 weeks before being removed and rephotographed. The lengths of 10 spines per juvenile were measured in the pre- and post-experiment photographs using ImageJ and the difference calculated to get a growth rate per juvenile. Seawater parameters of treatments were measured at the beginning of the experiment and subsequently once a day until the end of the experiment. Detailed information of the spreadsheets are as follows: A ingens (pre-exp) i.e. juvenile Abatus ingens spine lengths measured before exposure to experimental treatments. Column headings are: Spine number and length (mm): Length of each spine (1 - 10) measured per juvenile in mm. R1 - R12: Number of juveniles A ingens (post-exp) i.e. juvenile Abatus ingens spine lengths measured after 4-week exposure to experimental treatments. Column headings are identical to the above. A shackletoni (pre-exp) i.e. juvenile Abatus shackletoni spine lengths measured before exposure to experimental treatments. Column headings are identical to the above. A shackletoni (post-exp) i.e. juvenile Abatus shackletoni spine lengths measured after 4-week exposure to experimental treatments. Column headings are identical to the above. 2011-12 Aquarium pH and temp main headings show different treatment parameters. Column sub-headings are: Date - Date of measured seawater parameters Salinity - salinity of seawater measured Ppm - Amount of CO2 gas pumped into water recorded in parts per million pH - measured pH of seawater using NIST-certified buffers MV - pH of seawater recorded in millivolts Total pH - total pH of seawater derived from MV Temp - Temperature of seawater measured in degrees C.
In 2010-11 70mm soil cores were collected from locations at Macquarie Island rich in the invasive plant Poa annua. The cores were collected at 22 sites, with 10 samples per site. Processing and identification of species was completed in 2016. This file contains three spreadsheets: site descriptions, complete sample descriptions and abundance of springtail species at the sites. The work was carried as part of Australian Antarctic Science (AAS) Project 4024 and is currently being written up into several papers. The 'Quad veg' column gives the percentage vegetation cover in the one metre square quadrat. The 'sample veg' column gives the percentage vegetation cover in the 70mm soil core. The numbers in these columns are percentages and the letters are abbreviations for vegetation types: pa = Poa annua, cal = Callitriche sp., ttg = tall tussock grassland (Poa foliosa), sg = short grassland (range of species), colo = Colobanthus spp. In the 'rabbit presence' column 1 means there was evidence of rabbit presence in the quadrat and 0 means otherwise.
In 2010-11 a whole island survey or Macquarie Island was undertaken by Justine Shaw and Aleks Terauds. Quadrats (1m * 1m and 10m *10m) formed the basis of these surveys. At a minimum, quadrats were surveyed at the centroid of each 1 km * 1 km grid square. Other quadrats were surveyed along the survey track depending on the presence of non-native plants. Native plant coverage was also recorded in most quadrats. The download file contains an Excel spreadsheet. The spreadsheet contains three worksheets, two of which contain keys to the third worksheet (the data worksheet). Information from the two keys is summarised below: Key to Field Headings Island was divided into 1 km x 1 km cells (see associated shapefile). A ‘track’ of minimum length 750 m (and usually between 1-2 km) was walked through each cell from 1 km centroid to 1 km centroid (again with 1 m2 and 10 m2 quadrats). At a minimum, the centroid of each cell was surveyed for alien plants using a 1 m2 and 10 m 2 quadrat. Other quadrat based surveys were carried out along the track (again with 1 m2 and 10 m2 quadrats) when alien plants were detected. In most cases native plant coverage was also noted in each quadrat. Percentage cover was calculated for Poa annua, Cerastium fontanum, and Stellaria media. Number of plants was also documented for Cerastium fontanum and Stellaria media, not Poa annua as individual plants can’t be easily identified. The presence or absence of alien species was recorded along each track. For analytical purposes, each track was divided into 10 m segments, and the presence or absence of alien plants in these was then used to calculate the ‘proportion’ of each plant in each 1 km cell. For example, a 1km track through a cell has 100 ten metre segments, if 40 of these had Poa annua present, then the cell was allocated a proportional value of 40% for Poa annua (see shapefiles for actual data and visual representation). ID Cell ID LongitudeI Centroid of 1km cell longitude LatitudeI Centroid of 1km cell latitude C_poa 1x1 m quadrat percentage cover of Poa annua - note no number of plants for Poa annua because separate plants can't be identified C_cfA 1x1 m quadrat percentage cover of Ceastium fontanum C_cfN 1x1 m number of Cerastium fontanum plants in quadrat C_smA 1x1 m quadrat percentage cover of Stellaria media C_smN 1x1 m number of Stellaria media plants Q_poa 10 x10 m quadrat percentage cover n of Poa annua -- note no number of plants for Poa annua because separate plants can't be identified Q_cfA 10 x10 m quadrat percentage cover of Ceastium fontanum Q_cfN 10 x10 m number of Cerastium fontanum plants in quadrat Q_smA 10 x10 m quadrat percentage cover of Stellaria media Q_smN 10 x10 m number of Stellaria media plants Q_veg native veg composition - see attached worksheet for key Q_rab rabbit grazing present? (centroid only) Q_die Azorell dieback present? (centroid only) Vegetation key, numbers are percentage cover, will generally add up to 100 az Azorella macquariensis fm feldmark bare no veg hb herbfield - Megaherbs - mainly Pleurophyllum sc complex of short grass, typically Agrostis, Luzula, Festuca, co Colobanthus spp. (also sometimes colo) by bryophytres mr mire pa poa annua sg short grassland sh short herbs, Acaena spp, Cardamine sp., Montia sp. sgh short grass herb complex ttg tall tussock grass, typical Poa foliosa DR damaged by rabbits
Experimental Set-up: An unreplicated, 6-level, dose-response experiment was conducted on a natural microbial community over a range of pCO2 levels (343, 506, 634, 953, 1140 and 1641 micro atm). Seawater was collected on the 19th November 2014 approximately 1 km offshore from Davis Station, Antarctica (68 degrees 35' S, 77 degrees 58' E) from an area of ice-free water amongst broken fast-ice. The seawater was collected using a thoroughly rinsed 720L Bambi bucket slung beneath a helicopter and transferred into a 7000 L polypropalene reservoir tank. Six 650 L polyethene tanks (minicosms), located in a temperature-controlled shipping container, were immediately filled via teflon lined house via gravity with an in-line 200 micron Arkal filter to exclude metazooplankton. The minicosms were simultaneously filled to ensure they contained the same starting community. The ambient water temperature at time of collection was -1.0 degrees C and the minicosms were maintained at a temperature of 0 degrees C plus or minus 0.5 degrees C. At the centre of each minicosm there was an auger shielded for much of its length by a tube of polythene. This auger was rotated at 15 rpm to gently mix the contents of the tanks. Each minicosm tank was covered with an acrylic air-tight lid to prevent pCO2 off-gasing outside of the minicosm headspace. The minicosm experiment was conducted between the 19th November and the 7th December 2014. Initially, the contents of the tanks were given a day to equibrate to the minicosms. This was followed by a five day acclimation period to increasing pCO2 at low light (0.8 plus or minus 0.2 micro mol m-1 s-1), allowing cell physiology to acclimated to the pCO2 increase (days 1-5). During this period the pCO2 was progressively adjusted over five days to the target level for each tank (343 - 1641 micro atm). Thereafter pCO2 was adjusted daily to maintain the pCO2 level in each treatment (see carbonate chemistry section below). Following acclimation to the various pCO2 treatments light was progressively adjusted to 89 plus or minus 16 micro mol m-2 s-1 at a 19 h light:5 h dark cycle. The community was incubated and allowed to grow for a further 10 days (days 8-18) with target pCO2 adjusted back to target each day (see carbonate chemistry section below). For a more detailed description of minicosm set-up, lighting and carbonate chemistry see; Davidson, A. T., McKinlay, J., Westwood, K., Thomson, P. G., van den Enden, R., de Salas, M., Wright, S., Johnson, R., and Berry, K.:Enhanced CO2 concentrations change the structure of Antarctic marine microbial communities, Mar. Ecol. Prog. Ser., 552, 93-113, 2016. Deppeler, S. L., Petrou, K., Westwood, K., Pearce, I., Pascoe, P., Schulz, K. G., and Davidson, A. T.: Ocean acidification effects on productivity in a coastal Antarctic marine microbial community, Biogeosciences, 2017. Light microscopy sampling and analysis: Samples from each minicosm were collected on days 1, 3, 5, 8, 10, 12, 14, 16 and 18 for microscopic analysis to determine protistan identity and abundance. Approximately 960 mL were collected from each tank, on each day. Samples were fixed with 20 40 mL of Lugol's iodine and allowed to sediment out at 4 degrees C for greater than or equal to 4 days. Once cells had settled the supernatant was gently aspirated till approximately 200 mL remained. This was transferred to a 250 mL measuring cylinder, again allowed to settle (as above), and the supernatant gently aspirated. The remaining 20 mL. This final 20 mL was transferred into a 30 mL amber glass bottle. All samples were stored and transported at 4 degrees C to the Australian Antarctic Division, Hobart, Australia for analysis. Lugols-fixed and sedimented samples were analysed by light microscopy between July 2015 and February 2017. Between 2 to 10 mL (depending on cell-density) of lugols-concentrated samples was placed into a 10 mL Utermohl cylinder (Hydro-Bios, Keil) and the cells allowed to settle overnight. Due to the large variation in size and taxa, a stratified counting procedure was employed to ensure both accurate identification of small cells and representative counts of larger cells. All cells greater than 20 microns were identified and counted at 20x magnification; those less than 20 microns at 40x magnification. For larger cells (greater than 20 microns), 20 randomly chosen fields of view (FOV) at 3.66 x 106 microns2 counted to gain an average cells per L. For smaller cells (less than 20 microns), 20 randomly chosen FOVs at 2.51 x 105 microns2 were counted. Counts were conducted on an Olympus IX 81 microscope with Nomarski interference optics. Identifications were determined using (Scott and Marchant, 2005) and FESEM images. Autotrophic protists were distinguished from heterotrophs via the presence of chloroplasts and based on their taxonomic identity. Electron microscopy sampling and analysis: A further 1 L was taken on days 0, 6, 13 and 18 for analysis by Field Emission Scanning Electron Microscope (FESEM). 25 These samples were concentrated to 5 mL by filtration over a 0.8 micron polycarbonate filter. Cells were resuspended, the concentrate transferred to a glass vial and fixed to a final concentration of 1% EM-grade gluteraldehyde (ProSciTech Pty Ltd). All samples were stored and transported at 4 degrees C to the Australian Antarctic Division, Hobart, Australia for analysis. Gluteraldehyde-fixed samples were prepared for FESEM imaging using a modified polylysine technique (Marchant and Thomas, 30 1983). In brief, a few drops of gluteraldehyde-fixed sample were placed on polylysine coated cover slips and post-fixed with OsO4 (4%) vapour for 30 min, allowing cells to settle onto the coverslips. The coverslips were then rinsed in distilled water and dehydrated through a graded ethanol series ending with emersion in 100% dry acetone before being critically point dried in a Tousimis Autosamdri-815 Critical Point Drier. The coverslips were mounted onto 12.5 mm diameter aluminium stubs and sputter-coated with 7 nm of platinum/palladium in a Cressington 208HRD coater. Imaging of stubs was conducted by JEOL JSM6701F FESEM and protists identified using (Scott and Marchant, 2005). All units are in cells per L estimates from individual field of view counts (FOV) Protistan taxa and functional group descriptions and abbreviations: Autotrophic Dinoflagellate (AD) - including Gymnodinium sp., Heterocapsa and other unidentified autotrophic dinoflagellates Bicosta antennigera (Ba) Chaetoceros (Cha) - mainly Chaetoceros castracanei and Chaetoceros tortissimus but also other Chaetoceros present including C. aequatorialis var antarcticus, C. cf. criophilus, C. curvisetus, C. dichaeta, C. flexuosus, C. neogracilis, C. simplex Choanoflagellates (except Bicosta) (Cho) - mainly Diaphanoeca multiannulata but also Parvicorbicula circularis and Parvicorbicula socialis present in low numbers Ciliates (Cil) - mostly cf. Strombidium but other ciliates also present Discoid Centric Diatoms greater than 40 microns (DC.l) - unidentified centrics of the genera Thalassiosira, Landeria, Stellarima or similar Discoid Centric Diatoms 20 to 40 microns (DC.m) - unidentified centrics of the genera Thalassiosira, Landeria, Stellarima or similar Discoid Centric Diatoms less than 20 microns (DC.s) - unidentified centrics of the genera Thalassiosira Euglenoid (Eu) - unidentified Fragilariopsis greater than 20 microns (F.l) - mainly Fragilariopsis cylindrus, some Fragilariopsis kerguelensis and potentially some Fragilariopsis curta present in very low numbers Fragilariopsis less than 20 microns (F.s) - mainly Fragilariopsis cylindrus, and potentially some Fragilariopsis curta present in very low numbers Heterotrophic Dinoflagellates (HD) - including Gyrodinium glaciale, Gyrodinium lachryma, other Gyrodinium sp., Protoperidinium cf. antarcticum and other unidentified heterotrophic dinoflagellates Landeria annulata (La) Other Centric Diatoms (OC) - Corethronb pennatum, Dactyliosolen tenuijuntus, Eucampia antarctica var recta, Rhizosolenia imbricata and other Rhizosolenia sp. Odontella (Od) - Odontella weissflogii and Odontella litigiosa Other Flagellates (OF) - Dictyocha speculum, Chrysochromulina sp., unknown haptophyte, Phaeocystis antarctica (flagellate and gamete forms), Mantoniella sp., Pryaminmonas gelidicola, Triparma columaceae, Triparma laevis subsp ramispina, Geminigera sp., Bodo sp., Leuocryptos sp., Polytoma sp., cf. Protaspis, Telonema antarctica, Thaumatomastix sp. and other unidentified nano- and picoplankton Other Pennate Diatoms (OP) - Entomonei kjellmanii var kjellmanii, Navicula gelida var parvula, Nitzschia longissima, other Nitzschia sp., Plagiotropus gaussi, Pseudonitzschia prolongatoides, Synedropsis sp. Phaeocystis antarctica (Pa) - colonial form only Proboscia truncata (Pro) Pseudonitzschia subcurvata (Ps) Pseudonitzschia turgiduloies (Pt) Stellarima microtrias (Sm) Thalassiosira antarctica (Ta) Thalassiosira ritscheri (Tr) *.se = standard error for mean cell per L estimate ie. Tr.se = standard error for the mean cells per L for Thalassiosira ritscheri based on individual FOV estimates as described in methods above. Davis Station Antarctica Experiment conducted between 19th November and 7th December 2014.
An unreplicated, six-level dose-response experiment was conducted using 650 L incubation tanks (minicosms) adjusted to fugacity of carbon dioxide (fCO2) from 343 to 11641 uatm. The minicosms were filled with near-shore water from Prydz Bay, East Antarctica and the protistan composition and abundance was determined by microscopy analysis of samples collected during the 18 day incubation. Abundant taxa with low variance were examined separately, but rare taxa with high variance were combined into functional groups (descriptions below). Cluster analyses and ordinations were performed on Bray-Curtis resemblance matrixes formed from square-root transformated abundance data. This transformation was assessed as appropriate for reducing the influence of abundance species, as judged from a one-to-one relationship between observed dissimilarities and ordination distances (ie. Shepard diagram, not shown). The Bray-Curtis metric was used as it is recommended for ecological data due to its treatment of joint absences (ie. these do not contribute towards similarity), and giving more weight to abundant taxa rather than rare taxa. The data days 1 to 8 and then days 8 to 18 were analysed separately to distinguish community structure in the acclimation period and in the exponential growth phase during the incubation period of the experiment. Hierarchical agglomerative cluster analyses, based on the Bray-Curtis resemblance matrix, was performed using group-average linkage. Significantly different clusters of samples were determined using SIMPROF (similarity profile permutations method) with an alpha value of 0.05 and based on 1000 permutations. An unconstrained ordination by non-metric multidimensional scaling (nMDS) was performed on the resemblance matrix with a primary (`weak') treatment of ties. This was repeated over 50 random starts to ensure a globally optimal solution according to . Clusters are displayed in the nMDS using colour. Weighted average of sample scores are shown in the nMDS to show the approximate contribution of each species to each sample. The assumption of a linear trend for predictors within the ordination was checked for each covariate, and in all instances was found to be justified. A constrained canonical analysis of principal coordinates (CAP) was conducted according to the Vegan protocol using the Bray-Curtis resemblance matrix. This analysis was used to assess the significance of the environmental covariates, or constraints, in determining the microbial community structure. Unlike the nMDS ordination, the CAP analysis uses the resemblance matrix to partition the total variance in the community composition into unconstrained and constrained components, with the latter comprising only the variation that can be attributed to the constraining variables, fCO2, Si, P and NOx. Random reassignment of sample resemblance was performed over 199 permutations to compute the pseudo-F statistic as a measure of significance of each environmental constraint in the structural change of the microbial community. A forward selection strategy was used to choose a minimum subset of significant constraints that still account for the majority of the variation within the microbial community. All analysis were performed using R v1.0.136 and the add-on package vegan v2.4-2. Protistan taxa and functional group descriptions and abbreviations: Autotrophic Dinoflagellate (AD) - including Gymnodinium sp., Heterocapsa and other unidentified autotrophic dinoflagellates Bicosta antennigera (Ba) Chaetoceros (Cha) - mainly Chaetoceros castracanei and Chaetoceros tortissimus but also other Chaetoceros present including C. aequatorialis var antarcticus, C. cf. criophilus, C. curvisetus, C. dichaeta, C. flexuosus, C. neogracilis, C. simplex Choanoflagellates (except Bicosta) (Cho) - mainly Diaphanoeca multiannulata but also Parvicorbicula circularis and Parvicorbicula socialis present in low numbers Ciliates (Cil) - mostly cf. Strombidium but other ciliates also present Discoid Centric Diatoms greater than 40 microns (DC.l) - unidentified centrics of the genera Thalassiosira, Landeria, Stellarima or similar Discoid Centric Diatoms 20 to 40 microns (DC.m) - unidentified centrics of the genera Thalassiosira, Landeria, Stellarima or similar Discoid Centric Diatoms less than 20 microns (DC.s) - unidentified centrics of the genera Thalassiosira Euglenoid (Eu) - unidentified Fragilariopsis greater than 20 microns (F.l) - mainly Fragilariopsis cylindrus, some Fragilariopsis kerguelensis and potentially some Fragilariopsis curta present in very low numbers Fragilariopsis less than 20 microns (F.s) - mainly Fragilariopsis cylindrus, and potentially some Fragilariopsis curta present in very low numbers Heterotrophic Dinoflagellates (HD) - including Gyrodinium glaciale, Gyrodinium lachryma, other Gyrodinium sp., Protoperidinium cf. antarcticum and other unidentified heterotrophic dinoflagellates Landeria annulata (La) Other Centric Diatoms (OC) - Corethronb pennatum, Dactyliosolen tenuijuntus, Eucampia antarctica var recta, Rhizosolenia imbricata and other Rhizosolenia sp. Odontella (Od) - Odontella weissflogii and Odontella litigiosa Other Flagellates (OF) - Dictyocha speculum, Chrysochromulina sp., unknown haptophyte, Phaeocystis antarctica (flagellate and gamete forms), Mantoniella sp., Pryaminmonas gelidicola, Triparma columaceae, Triparma laevis subsp ramispina, Geminigera sp., Bodo sp., Leuocryptos sp., Polytoma sp., cf. Protaspis, Telonema antarctica, Thaumatomastix sp. and other unidentified nano- and picoplankton Other Pennate Diatoms (OP) - Entomonei kjellmanii var kjellmanii, Navicula gelida var parvula, Nitzschia longissima, other Nitzschia sp., Plagiotropus gaussi, Pseudonitzschia prolongatoides, Synedropsis sp. Phaeocystis antarctica (Pa) - colonial form only Proboscia truncata (Pro) Pseudonitzschia subcurvata (Ps) Pseudonitzschia turgiduloies (Pt) Stellarima microtrias (Sm) Thalassiosira antarctica (Ta) Thalassiosira ritscheri (Tr) *.se = standard error for mean cell per L estimate ie. Tr.se = standard error for the mean cells per L for Thalassiosira ritscheri based on individual FOV estimates as described in methods above.
An ecotoxicological risk assessment of groundwater from two Macquarie Island fuel spill sites was conducted to assess the level of risk posed by the sites to the adjacent marine receiving environment. Experiments were conducted on Macquarie Island during the summer season of 2017/18. The two fuel spill sites (known as: Fuel Farm and Power House, see file: Map-macquarie_building_and_structures_14676.pdf) within the vicinity of the Macquarie Island research station had undergone intensive in situ remediation by the Australian Antarctic Division over the previous decade. Despite remediation efforts, groundwater leaching from the sites continued to contain some residual fuel contamination, with sheen observed at several shoreline seeps and chemical analysis of groundwater samples confirmed some hydrocarbon contamination remained. This study aimed to assess the level of residual risk posed by groundwater from these sites as it enters the adjacent marine environment. We ran a series of toxicity tests using composited samples of salinity-adjusted groundwater discharge, as an exposure medium to test the sensitivity of 11 locally collected marine invertebrate species to the groundwater. Groundwater sampling was conducted over two periods: 23-29/11/17 and 18-20/12/17, for use in two rounds of toxicity testing (referred to as test round 1 (A and B) and test round 2). Groundwater samples were collected from 22 groundwater monitoring points; 12 surface seeps and 7 previously installed piezometers. These monitoring points were located along the coastal margin of the of the fuel spill sites, at their boundary with the adjacent marine environment (see: Locations-Fuel Farm-groundwater monitoring.pdf and Locations-Powerhouse-groundwater monitoring.pdf). The 22 groundwater samples were used to prepare seven salinity-adjusted composite test solutions (TS), each composed of equal volumes of up to nine groundwater samples. Salinity adjustment was to approximately that of ambient seawater (34 ppt), using hypersaline brine (prepared from locally collected clean seawater, which was frozen, then partially defrosted to collect concentrated brine). A total of approximately 6 L of was prepared for each of the seven TSs. See file: MI Ecotox-2017-18_TestSolutions_v03.xlsx for TS details (including: collection, preparation and physicochemical analysis results). Eleven locally collected marine invertebrate species were used in the tests. Biota were collected from two sites on Macquarie Island, both within the vicinity of the research station but away from areas of known fuel contamination: 1). Garden Bay on the East Coast (54° 29' 56.9" S, 158° 56' 28.8" E) and 2). Hasselborough Bay on the West Coast (54° 29' 45.6" S, 158° 55' 55.8" E). See: Map-macquarie_building_and_structures_14676.pdf. Dates of collection of test biota were 1/12/2017 (for test round 1A), 6/12/2017 (for test round 1B) and 20 and 22/12/17 (for test round 2). The 11 test taxa were from six broad taxonomic groups: 2 amphipods (Paramoera sp., Parawaldeckia kidderi), 2 flatworms (Obrimoposthia wandeli, Obrimoposthia ohlini), 2 copepods (Tigriopus angulatus, Harpacticus sp.), 2 gastropods (Laevilitorina caliginosa, Macquariella hamiltoni), 2 bivalves (Gaimardia trapesina, Lasaea hinemoa) and 1 isopod (Exosphaeroma gigas). Test biota were observed for 14 or 21 days and survival observed periodically. Full details of toxicity test conditions are provided in the file: MI Ecotox-2017-18_RawTestObs v02.xlsx (worksheets: TestSummary, Species and Endpoints). This file also contains, on subsequent worksheets, the raw toxicity test observations for each text taxa. These raw result data are compiled in the file: MI Ecotox-2017-18_Test-DATA.xlsx, worksheet: Survival-ALL contains survival data for all tests and taxa. Subsequent worksheets provide data for each test taxa separately and also include any sublethal observations that were made. All data associated with test solution collection, composition and chemistry are provided in the file: MI Ecotox-2017-18_TestSolutions.xlsx. The following (A. – I.) provides a description for the files provided with this record: A. MI Ecotox-2017-18_A-Map-Groundwater monitoring sites.png Images of study sites. A.) Overall Macquarie Island station environment, with Fuel Farm (red) and Power House (blue) indicated and showing the close proximity of the two land based sites to the adjacent high energy marine receiving environment. B.) Line map indicating relative location sites; Power House (blue) and Fuel Farm (red) sites, within the Macquarie Island station area. C.) and D.) Aerial images of the two sites, showing groundwater monitoring point locations (piezometers and seeps) used to prepare the seven test solutions (TS) as per key; Power House (TS4 and TS5) and Fuel Farm (TS1, TS2, TS3, TS6 and TS7), respectively. Monitoring point labels correspond with those provided in the file: MI Ecotox-2017-18_D-TestSolutions.xlsx / TS-Collection. B. MI Ecotox-2017-18_B-Map-macquarie_building_and_structures_14676.pdf Map of overall Macquarie Island station area, showing locations referred to in this study relative to other station infrastructure; Fuel Farm and Power House (land based fuel contaminated sites) and Hasselborough Bay and Garden Bay (clean marine areas for collection of test biota). Produced by the Australian Antarctic Data Centre, July 2018. Map available at: https://data.aad.gov.au/aadc/mapcat/. Map Catalogue No. 14676. © Commonwealth of Australia 2018. C. MI Ecotox-2017-18_C-RawTestObs.xlsx Toxicity test condition details (in worksheets named: TestSummary, Species, Endpoints) and raw toxicity test observations for each text taxa (in subsequent worksheets). D. MI Ecotox-2017-18_D-TestSolutions.xlsx Details of test solutions, including collection, composition and chemistry. E. MI Ecotox-2017-18_E-Test-DATA.xlsx Compiled raw toxicity test results in long format. Worksheet: Survival-ALL contains survival data for all tests and taxa. Subsequent worksheets provide data for each test taxa separately and includes sublethal observations if made). F. MI Ecotox-2017-18_F-ScanLabBook.pdf Scanned copy of the laboratory notebook associated with these tests. Notes were recorded by Cath King and Jessica Holan during the 17/18 Macquarie Island field season. G. MI Ecotox-2017-18_G-ScanObservationSheets.pdf Scanned copy of the handwritten raw observation sheets used to record test observations (observations scored by: Cath King and Jessica Holan). H. MI Ecotox-2017-18_H-ChemicalAnalysis-ALS-COA.pdf Certificate of Analysis for chemistry results for samples analysed by Australian Laboratory Services (ALS) Environmental, Melbourne. Includes Total Recoverable Hydrocarbons (TRH; with and without silica gel clean up), nutrients (nitrogen) and a standard toxicity test (Microtox). Client sample ID with “Ecotox TS” prefix are those relevant to this study (other samples are associated with broader site remediation monitoring for the 17/18 season). I. MI Ecotox-2017-18_I-ChemicalAnalysis-ALS-QAQC.pdf Quality Assurance (QA) and Quality Control (QC) report provided by ALS, in association with the Certificate of Analysis. As previous, Client sample ID with “Ecotox TS” prefix are relevant to this study. J. MI Ecotox-2017-18_J-size measurements.zip Measures of specimen body lengths (mm). The .zip file contains a text file named: SizeMeasurements-README.txt, providing a description of the content associated with these data.
The collection aims to showcase the range of Southern Ocean diatom species found in the major hydrological provinces of the Australian Sector of the Southern Ocean along the 140 degrees E. The collection includes specimens collected in the Sub-Antarctic Zone (SAZ), Polar Frontal Zone (PFZ) and Antarctic Zone (AZ). Samples were collected with McLane Parflux time series sediment traps placed at several depths in the SAZ (47 degrees S site), PFZ (54 degrees S site) and AZ and (61 degrees S site) during the decade 1997-2007. The shortest sampling intervals were eight days and corresponded with the austral summer and autumn, whereas the longest interval was 60 days and corresponded with austral winter. Split aliquots were obtained for taxonomic analysis via scanning electron microscopy (SEM). For improved taxonomic imaging, samples were treated with hydrochloric acid and hydrogen peroxide to remove carbonates and organic matter, respectively. A micropipette was used to transfer the suspension of selected samples to a round-glass cover slip following standard decantation method outlined by Barcena and Abrantes (1998). Samples were air-dried and coated with gold for SEM analysis. SEM analysis was carried out using a JEOL 6480LV scanning electron microscope. Taxonomy Diatoms include all algae from the Class Bacillariophyceae and follow the standardised taxonomy of World Register of Marine Species (WoRMS). Order Asterolamprales Family Asterolampraceae Asteromphalus hookeri Ehrenberg Asteromphalus hyalinus Karsten Order Achnanthales Family Cocconeidaceae Cocconeis sp. Order Bacillariales Family Bacillariaceae Fragilariopsis curta (Van Heurck) Hustedt Fragilariopsis cylindrus (Grunow) Krieger Fragilariopsis kerguelensis (O'Meara) Hustedt Fragilariopsis pseudonana (Hasle) Hasle Fragilariopsis rhombica (O'Meara) Hustedt Fragilariopsis separanda Hustedt Nitzschia bicapitata Cleve Nitzschia kolaczeckii Grunow Nitzschia sicula (Castracane) Husted var. bicuneata (Grunow) Hasle Nitzschia sicula (Castracane) Husted var. rostrata Hustedt Pseudo-nitzschia heimii Manguin Pseudo-nitzschia lineola (Cleve) Hasle Pseudo-nitzschia turgiduloides Hasle Order Chaetocerotanae incertae sedis Family Chaetoceraceae Chaetoceros aequatorialis var. antarcticus Cleve Chaetoceros atlanticus Cleve Chaetoceros dichaeta Ehrenberg Chaetoceros peruvianus Brightwell Chaetoceros sp. Order Corethrales Family Corethraceae Corethron spp. Order Coscinodiscales Family Coscinodiscaceae Stellarima stellaris (Roper) Hasle et Sims Family Hemidiscaceae Actinocyclus sp. Azpeitia tabularis (Grunow) Fryxell et Sims Hemidiscus cuneiformis Wallich Roperia tesselata (Roper) Grunow Order Hemiaulales Family Hemiaulaceae Eucampia antarctica (Castracane) Mangin Order Naviculales Family Plagiotropidaceae Tropidoneis group Family Naviculaceae Navicula directa (Smith) Ralfs Family Pleurosigmataceae Pleurosigma sp. Order Rhizosoleniales Family Rhizosoleniaceae Dactyliosolen antarcticus Castracane Rhizosolenia antennata f. semispina Sundstrom Rhizosolenia antennata (Ehrenberg) Brown f. antennata Rhizosolenia cf. costata Gersonde Rhizosolenia polydactyla Castracane f. polydactyla Rhizosolenia simplex Karsten Proboscia alata (Brightwell) Sundstrom Proboscia inermis (Castracane) Jordan Ligowski Order Thalassiosirales Family Thalassiosiraceae Porosira pseudodenticulata (Hustedt) Jouse Thalassiosira ferelineata Hasle et Fryxell Thalassiosira gracilis (Karsten) Hustedt Thalassiosira lentiginosa (Janisch) Fryxell Thalassiosira oestrupii (Ostenfeld) Hasle var. oestrupii Fryxell et Hasle Thalassiosira oliveriana (O'Meara) Makarova et Nikolaev Thalassiosira tumida (Janisch) Hasle Order Thalassionematales Family Thalassionemataceae Thalassionema nitzschioides var. lanceolatum Grunow Thalassiothrix antarctica Schimper ex Karsten Data available: 73 SEM images of the most abundant diatom species found at the three sampling sites. Samples were collected by several sediment traps placed at different depths in the Subantarctic Zone (47 degrees S site), Polar Frontal Zone (54 degrees S site) and Antarctic Zone (61 degrees S site) during the decade 1997-2007. The collection site and date for each species image can be found in Table 1 (see the word document in the download file).
Diatom and biogenic particle fluxes were investigated over a two-year and six-year periods at the Subantarctic and Polar Frontal Zones, respectively, in the Australian Sector of the Southern Ocean. Both sites were located along ~ 140 degrees E: station 47 degrees S was set on the abyssal plain of the central SAZ whereas station 54 degrees S was placed on a bathymetric high of the Southeast Indian Ridge in the PFZ. The data sets contain diatom species and biogeochemical flux data measured at 1000 m at the 47 degrees S site between 1999-2001 and at 800 m at the 54 degrees S site during six selected years between 1997-2007. All traps were MacLane Parflux sediment traps: conical in shape with a 0.5 m2 opening area and equipped with a carousel of 13 or 21 sampling cups. Shortest intervals corresponded with the austral summer and autumn ranging typically between 4.25 and 10 days, whereas the longest intervals were 60 days and corresponded with winter. Total fluxes of particulates at both traps were highly seasonal, with maxima registered during the austral spring and summer and very low fluxes during winter. Seasonality was more pronounced in the 54 degrees S site. Biogenic silica (SiO2) was the dominant bulk component in the PFZ while carbonate (CaCO3) dominated the particle fluxes at the SAZ. POC export was relatively similar between sites despite significant differences in the total diatom flux. Diatom frustules from 94 taxa were identified over the entire experiment. The dominant species of the diatom assemblage was Fragilariopsis kerguelensis at both sites, representing 43% and 59% of the integrated diatom assemblage at the 47 degrees S and 54 degrees S sites, respectively. Secondary contributors to the diatom assemblage at the 47 degrees S were Azpeitia tabularis, Thalassiosira sp. 1, Nitzschia bicapitata, resting spores of Chaetoceros spp., Thalassiosira oestrupii var. oestrupii, Hemidiscus cuneiformis and Roperia tesselata. Subordinate contributions to the diatom assemblage correspond to Pseudo-nitzschia lineola cf. lineola, Pseudo-nitzschia heimii, Thalassiosira gracilis group and Fragilariopsis pseudonana, Fragilariopsis rhombica and Thalassiosira lentiginosa. Data available: two excel files containing sampling dates and depths, raw counts, relative abundance and fluxes (valves m-2 d-1) of the diatom species, and biogenic particle fluxes measured at 1000 m and 800 m depth at the 47 degrees S and 54 degrees S sites, respectively. Each file contains four spreadsheets: raw diatom valve counts, relative abundance of diatom species and valve flux of diatom species and biogenic particle composition and fluxes. Detailed information of the column headings is provided below. Cup - Cup (=sample) number Depth - vertical location of the sediment trap in meters below the surface Mid-point date - Mid date of the sampling interval Length (days) - number of days the cup was open Girdle bands instead of valves were counted for Dactyliosolen antarcticus Castracane. Therefore, D. antarcticus girdles counts were not included in relative abundance calculations. Dates of data collection: 47 degrees S site: July 1999 - October 2001 (two-year record) 54 degrees S site: September 1997 - February 1998, July 1999 - August 2000, November 2002 - October 2004 and December 2005 - October 2007 (six-year record).
Seeds of twelve plant species were collected from Macquarie Island during January and February 2013. The seeds were used in a series of laboratory-based tests during 2013, at the University of Wollongong. Tests were conducted to determine species suitably for use in laboratory-based toxicity testing, using germination success and seedling growth (shoot and root length) as end points. Two soil types (containing low and high organic carbon contents) were used, to reflect the variable organic carbon content found in soils at Macquarie Island. Test soils were spiked with Special Antarctic Blend (SAB) diesel fuel and aged for 14 days to generate a concentration series of SAB-contaminated soils. Exposure doses were quantified as the concentration of total petroleum hydrocarbons (TPH, nC9-nC18) on a soil dry mass basis. Based on germination success in initial trials, four species (Colobanthus muscoides Hook.f., Deschampsia sp., Epilobium pendunculare A.Cunn. and Luzula crinita Hook.f.) were included in definitive toxicity tests. Description of files provided: - FILE: GabriellaMacoustra_Germination.xlsx Excel data file providing results of germination trials. Includes test development data (germination response of test species on test substrates without addition of fuel toxicants). - FILE: GabriellaMacoustra_Growth.xlsx Excel data file providing results of germination trials. Provides measurements from image analysis of roots and shoots of plants used in germination trials. - FILE: GabriellaMacoustra_Soil Characterisation.xlsx Excel data file providing soil characterisation data for the two soil substrates (sandy and peaty) used in the germination trials. Includes spiked fuel concentrations and a range of physicochemical properties. - FILE: Macoustra 2013_Thesis.pdf PDF file of University of Wollongong Honours thesis submitted by Gabriella Macoustra 2013. - FILES (Field and lab notebook scans): Notebook-Field_42420.pdf, Notebook-Field_42422.pdf, Notebook-Field_42398.pdf, Notebook-Lab_101036.pdf. Four scanned PDF files of field notes taken by Corrine de Mestre, related to seed collections on Macquarie Island during 2012/13.