Dinoflagellate cyst distribution over the past 9 kyrs BP on the east coast Tasmania, southeast Australia
Southeastern Australia's marine waters are undergoing a trend of increased warming, surpassing the global average. This area has emerged as an alluring location for research on planktic microfossils, particularly dinoflagellate cysts, which are abundant in contemporary and Late Quaternary sediments. The composition of dinoflagellate cyst assemblages offers valuable information about the physical and biogeochemical properties of mid-latitude waters in this region. This study presents an analysis of cyst assemblages from marine sediment cores from waters inshore and offshore Maria Island, Tasmania, southeast Australia, up to 9 kyrs BP. The dominant cysts were Protoceratium reticulatum, Protoperidinium spp. (P. avellana, P. conicum, P.minutum, P. oblongum, P. subinerme, P. shanghaiense) and Spiniferites spp. (S. bulloideus, S. hyperacanthus, S. membranaceus, S. mirabilis, S. pachydermus, and S. ramosus). Inshore, Spiniferites spp. were more abundant (up to 61%), while P. reticulatum was dominant (up to 80%) at the offshore site. Impagidinium spp. and Nematosphaeropsis labyrinthus were exclusively detected offshore, with their increasing occurrence from 6 kyrs BP to present suggesting a transition from shallow coastal to stable deep-water habitat. Cysts of the Alexandrium tamarense complex were detected over the past 140 years and 9 kyrs BP at the inshore and offshore sites respectively, indicating an endemic long-term presence. Low abundances of Gymnodinium catenatum cysts were detected exclusively inshore from 50 years ago to present, suggesting recent bloom events. The limited southward penetration of the East Australian Current is indicated by the lack of warm-water cyst taxa such as Lingulodinium machaerophorum. Unlike coccolithophores, previously studied in the same sediment core, no discernible shift from cold to warm-water dinoflagellate cyst species was observed. The documentation of dinoflagellate cyst assemblages presented in this study will aid in predicting the effects of climate change, eutrophication, and introduction of novel species on local and broader community dynamics.
Simple
Identification info
- Date (Publication)
- 2023-05-16
- Citation identifier
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doi:10.25959/24kp-r337
- Title
- Information and documentation - Digital object identifier system
- Date (Publication)
- 2023-05-16
- Citation identifier
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ISO 26324:2012
- Citation identifier
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https://doi.org/10.25959/24kp-r337
Resource provider
Author
- Credit
- This study was funded through the Australian Research Council (ARC Discovery Project DP170102261).
- Status
- Completed
Author
- Topic category
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- Biota
Extent
Temporal extent
- Time period
- 2020-05-01 2023-05-01
Vertical element
- Minimum value
- 30
- Maximum value
- 107
- Identifier
- EPSG::5715
- Name
- MSL depth
- Maintenance and update frequency
- Not planned
- Keywords (Theme)
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- East Australian Current
- Harmful Algal Bloom (HAB)
- Cyst
- Keywords (Taxon)
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- Protoceratium reticulatum
- Protoperidinium spp.
- Spiniferites spp.
- Impagidinium spp.
- Nematosphaeropsis labyrinthus
- Alexandrium tamarense
- Gymnodinium catenatum
- Global Change Master Directory Earth Science Keywords, Version 8.5
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- Data, products and services from IMAS are provided "as is" without any warranty as to fitness for a particular purpose.
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- This dataset is the intellectual property of the University of Tasmania (UTAS) through the Institute for Marine and Antarctic Studies (IMAS).
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https://licensebuttons.net/l/by/4.0/88x31.png
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- Title
- Creative Commons Attribution 4.0 International License
- Alternate title
- CC-BY
- Edition
- 4.0
- Website
-
https://creativecommons.org/licenses/by/4.0/
License Text
- Other constraints
- Cite data as: Paine, B. (2023). Dinoflagellate cyst distribution over the past 9 kyrs BP on the east coast Tasmania, southeast Australia [Data set]. Institute for Marine and Antarctic Studies (IMAS), University of Tasmania (UTAS). https://doi.org/10.25959/24KP-R337
- Language
- English
- Character encoding
- UTF8
Content Information
- Content type
- Physical measurement
Distribution Information
- Distribution format
-
-
Microsoft Excel
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Microsoft Excel
- OnLine resource
-
DATA ACCESS - zip package all files
Resource lineage
- Statement
- Sediment core collection and preparation In May 2018, a marine sediment gravity core (GC02-S1) measuring 268 cm in length was collected during the RV Investigator voyage INV2018_T02 at a water depth of 104 m near the continental shelf edge to the east of Maria Island (42.845°S; 148.240°E) (Fig. 1). To minimise disturbance caused by large gravity corers during sediment contact, a shorter, complementary core (12 cm) was obtained using a KC Denmark Multi-Corer at the same location, denoted as MCS1-T6 (where T6 refers to tube number 6 of the multi-corer). Additionally, a 35 cm-long multi-core (MCS3-T2) was collected from an inshore site within Mercury Passage on the western side of Maria Island. All cores were hermetically sealed, labelled, and transported to the Australian Nuclear Science Technology Organisation (ANSTO) in Lucas Heights, NSW, Australia, where they were stored at 4°C. Further information on core collection and preparation can be found in Paine et al. (2023). For this study, samples were analysed for inshore core MCS3-T2 at depth intervals of 2 cm at the top (to 8 centimetres below the seafloor (cmbsf)) then at 5 cm in the bottom (to 35 cmbsf). All MCS1-T6 samples were analysed at 2 cm depth intervals. All GC02-S1 samples were analysed at 10 cm depth intervals. Palynological treatment and microscopy preparation A total of 44 samples (10 from MCS3-T2, 6 from MCS1-T6 and 28 from GC02-S1) were weighed and rinsed in distilled water to remove salts. Palynological processing techniques followed methods by Anderson et al. (1995), whereby acid digestion is used to remove calcium carbonates and silicates. A known amount (1 capsule) of Lycopodium clavatum spores (sourced from the department of Geology, Lund University, Sweden, batch no. 938934, mean spores 16 per tablet = 10,679 ± 426) were added during the preparation of each sample to be used as an ‘abundance reference marker’ as per Stockmarr (1971). Samples were then rinsed three times in distilled water and wet sieved sequentially through a 250 µm and a 10 µm mesh to remove coarse and fine particles, respectively. The material collected on the 10 µm mesh was transferred to a 15 mL centrifugation tube (Falcon) and suspended in distilled water. Permanent-mount smear slides for light microscopy (LM) were prepared by pipetting the processed sample onto a glass microscope coverslip (Vitromed Basel 22 x 40 mm), smearing with a stainless-steel laboratory spatula, then allowing it to evaporate on a hotplate. A small drop of Norland optical adhesive #61 was added to a microscope slide (Knittel G300 26 x 76 x 1.0 mm), and the coverslip was positioned on top, then cured in sunlight. A fluorescent staining technique for the recognition and counting of Alexandrium spp. resting cysts developed by Yamaguchi et al. (1995) was applied to select unmounted sample preparations from inshore (MCS3-T2) and offshore (MCS1-T6 & GC02-S1) cores. The fluorochrome primulin stain targets cellulose and starches that comprise the wall and outer membranes of select cyst taxa making them fluoresce under UV light. Scanning electron microscopy (SEM) was used to aid taxonomic categorisation. Preparation of the sample for SEM analysis involved filtering processed samples onto Isopore Millipore 13mm disc filters (1.2µm pore size). The filters were left to dry at room temperature and mounted on Ted Pella standard SEM pin stubs (12.7mm surface diameter) with double-sided conductive carbon tabs (12 mm). Approximately 3 nm of platinum was applied to the prepared SEM sample stubs using a BalTec SCD 050 sputter coater. Microscopy Cysts were counted using a Nikon Eclipse Ci light microscope adhering to systematic transects of each slide at 200x magnification until a count total as close as possible to 100 cysts was achieved. Each sample was counted for dinoflagellate cysts and Lycopodium spores, and quantitative cysts per g-1 of sediment calculated by relating cysts to spore counts. The formula used to calculate cysts per unit measure was Ct = ((Tc/Lc) Ls / Wts), where Ct = concentration of cysts, Tc/Lc = cyst count divided by Lycopodium spore count, Ls = number of Lycopodium spores added, Wts = weight of sample. Taxonomic details and associated digital imagery were documented throughout the enumeration process. Further taxonomic analysis utilised a Hitachi SU-70 scanning electron microscope (SEM). Cyst identification was aided by reference material from McMinn et al. (2010) and the online dinoflagellate cyst identification key by Zonneveld and Pospelova (2015). Palynologists and biologists are known to use different names for the various life stages of the same organism. In this study, the biological name was favoured when available. In circumstances where cyst taxonomy (Spiniferites spp.) was more advanced than for their biological equivalents (Gonyaulax spp.), the former nomenclature was used.
- Hierarchy level
- Dataset
- Hierarchy level
- Dataset
Metadata
- Metadata identifier
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urn:uuid/22d27e9b-8b87-4c1e-901e-cf2a02e11a87
- Language
- English
- Character encoding
- UTF8
Distributor
Type of resource
- Resource scope
- Dataset
- Name
- IMAS Dataset level record
- Metadata linkage
-
https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/22d27e9b-8b87-4c1e-901e-cf2a02e11a87
Point of truth URL of this metadata record
- Date info (Creation)
- 2023-05-03T00:00:00
- Date info (Revision)
- 2023-10-30T11:20:05
Metadata standard
- Title
- ISO 19115-3:2018