ORCID Profile
0000-0002-6287-3283
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Physical Oceanography | Oceanography | Palaeoclimatology | Geomorphology and Regolith and Landscape Evolution | Glaciology | Climate Change Processes
Effects of Climate Change and Variability on Antarctic and Sub-Antarctic Environments (excl. Social Impacts) | Expanding Knowledge in the Environmental Sciences | Expanding Knowledge in the Earth Sciences | Antarctic and Sub-Antarctic Oceanography | Climate Change Models | Global Effects of Climate Change and Variability (excl. Australia, New Zealand, Antarctica and the South Pacific) (excl. Social Impacts) |
Publisher: American Geophysical Union (AGU)
Date: 04-2023
DOI: 10.1029/2022JG007252
Abstract: With ongoing climate change, research into the biological changes occurring in particularly vulnerable ecosystems, such as Antarctica, is critical. The Totten Glacier region, Sabrina Coast, is currently experiencing some of the highest rates of thinning across all East Antarctica. An assessment of the microscopic organisms supporting the ecosystem of the marginal sea‐ice zone over the continental rise is important, yet there is a lack of knowledge about the ersity and distribution of these organisms throughout the water column, and their occurrence and/or preservation in the underlying sediments. Here, we provide a taxonomic overview of the modern and ancient marine bacterial and eukaryotic communities of the Totten Glacier region, using a combination of 16S and 18S rRNA licon sequencing (modern DNA) and shotgun metagenomics (sedimentary ancient DNA, sed aDNA). Our data show considerable differences between eukaryote and bacterial signals in the water column versus the sediments. Proteobacteria and diatoms dominate the bacterial and eukaryote composition in the upper water column, while diatoms, dinoflagellates, and haptophytes notably decrease in relative abundance with increasing water depth. Little diatom sed aDNA is preserved in the sediments, which are instead dominated by Proteobacteria and Retaria. We compare the diatom microfossil and sed aDNA record and link the weak preservation of diatom sed aDNA to DNA degradation while sinking through the water column to the seafloor. This study provides the first assessment of DNA transfer from ocean waters to sediments and an overview of the microscopic communities occurring in the climatically important Totten Glacier region.
Publisher: Elsevier BV
Date: 09-2014
Publisher: American Geophysical Union (AGU)
Date: 12-2020
DOI: 10.1029/2020PA003981
Publisher: Elsevier BV
Date: 02-2018
DOI: 10.1016/J.MARGEN.2017.09.006
Abstract: The bio ersity, ecosystem services and climate variability of the Antarctic continent and the Southern Ocean are major components of the whole Earth system. Antarctic ecosystems are driven more strongly by the physical environment than many other marine and terrestrial ecosystems. As a consequence, to understand ecological functioning, cross-disciplinary studies are especially important in Antarctic research. The conceptual study presented here is based on a workshop initiated by the Research Programme Antarctic Thresholds - Ecosystem Resilience and Adaptation of the Scientific Committee on Antarctic Research, which focussed on challenges in identifying and applying cross-disciplinary approaches in the Antarctic. Novel ideas and first steps in their implementation were clustered into eight themes. These ranged from scale problems, through risk maps, and organism/ecosystem responses to multiple environmental changes and evolutionary processes. Scaling models and data across different spatial and temporal scales were identified as an overarching challenge. Approaches to bridge gaps in Antarctic research programmes included multi-disciplinary monitoring, linking biomolecular findings and simulated physical environments, as well as integrative ecological modelling. The results of advanced cross-disciplinary approaches can contribute significantly to our knowledge of Antarctic and global ecosystem functioning, the consequences of climate change, and to global assessments that ultimately benefit humankind.
Publisher: Informa UK Limited
Date: 02-2005
Publisher: Cambridge University Press (CUP)
Date: 26-03-2010
DOI: 10.1017/S0954102010000180
Abstract: Dense coral-sponge communities on the upper continental slope at 570–950 m off George V Land, East Antarctica have been identified as Vulnerable Marine Ecosystems. The challenge is now to understand their probable distribution on other parts of the Antarctic margin. We propose three main factors governing their distribution on the George V margin: 1) their depth in relation to iceberg scouring, 2) the flow of organic-rich bottom waters, and 3) their location at the head of shelf cutting canyons. Icebergs scour to 500 m in this region and the lack of such disturbance is a probable factor allowing the growth of rich benthic ecosystems. In addition, the richest communities are found in the heads of canyons which receive descending plumes of Antarctic Bottom Water formed on the George V shelf, which could entrain abundant food for the benthos. The canyons harbouring rich benthos are also those that cut the shelf break. Such canyons are known sites of high productivity in other areas due to strong current flow and increased mixing with shelf waters, and the abrupt, complex topography. These proposed mechanisms provide a framework for the identification of areas where there is a higher likelihood of encountering these Vulnerable Marine Ecosystems.
Publisher: Elsevier BV
Date: 09-2017
Publisher: Geological Society of London
Date: 26-09-2014
DOI: 10.1144/M41.18
Abstract: Prydz Bay and the Mac.Robertson Land Shelf exhibit many of the variations seen on Antarctic continental shelves. The Mac.Robertson shelf is relatively narrow with rugged, inner-shelf topography and shallow outer-shelf banks swept by the west-flowing Antarctic Coastal Current. U-shaped valleys cut across the shelf. It has thin sedimentary cover, deposited and eroded by cycles of glacial advance and retreat through the Neogene and Quaternary. Modern sedimentation is diatom-rich siliceous, muddy ooze in shelf deeps, while, on the banks, phytodetritus, calcareous bioclasts and terrigenous material are mixed by iceberg ploughing. Prydz Bay is a large embayment fed by the Amery Ice Shelf. It has a broad inner-shelf deep area and outer bank, with depths ranging from 2400 m beneath the ice shelf to 100 m on the outer banks. A clockwise gyre flows through the bay. Fine mud and siliceous ooze drape the seafloor however, banks are scoured by icebergs to depths as great as 500 m. The Mac.Robertson shelf has seen advances to the shelf edge during glacial episodes and retreat during warming and rising sea level. Prydz Bay shows more complexity, with parts of the bay showing partial advance of the ice-grounding zone.
Publisher: Springer Science and Business Media LLC
Date: 11-12-2017
DOI: 10.1038/S41559-017-0392-3
Abstract: Most seafloor communities at depths below the photosynthesis zone rely on food that sinks through the water column. However, the nature and strength of this pelagic-benthic coupling and its influence on the structure and ersity of seafloor communities is unclear, especially around Antarctica where ecological data are sparse. Here we show that the strength of pelagic-benthic coupling along the East Antarctic shelf depends on both physical processes and the types of benthic organisms considered. In an approach based on modelling food availability, we combine remotely sensed sea-surface chlorophyll-a, a regional ocean model and diatom abundances from sediment grabs with particle tracking and show that fluctuating seabed currents are crucial in the redistribution of surface productivity at the seafloor. The estimated availability of suspended food near the seafloor correlates strongly with the abundance of benthic suspension feeders, while the deposition of food particles correlates with decreasing suspension feeder richness and more abundant deposit feeders. The modelling framework, which can be modified for other regions, has broad applications in conservation and management, as it enables spatial predictions of key components of seafloor bio ersity over vast regions around Antarctica.
Publisher: Copernicus GmbH
Date: 15-05-2023
DOI: 10.5194/EGUSPHERE-EGU23-10006
Abstract: Maps of seabed geomorphology provide foundational information for a broad range of marine applications. To be most effective, geomorphic characterisation of the seabed requires standardised, multi-scalar and interjurisdictional approaches that can be applied locally, regionally and internationally using the best available data. An ongoing collaboration between geoscience agencies in the United Kingdom (BGS), Norway (GSN), Ireland (GSI UCC) and Australia (GA LU) has focused on developing a new standardised approach to meet this need. Dove et al (2016) first described a two-part approach for mapping the geomorphology of the seabed. Part 1 was subsequently published as an open access glossary that includes an illustrated list of terms and definitions that primarily draw on the International Hydrographic Organization standard (Dove et al, 2020). Morphology maps are created by applying Part 1 Morphological terms to bathymetry data. Part 2 classifies these mapped & shapes with their geomorphic interpretation geomorphic unit terms are structured within 11 geomorphic Settings (Fluvial, Coastal, Marine, Glacial, Hard Rock) and Process (Current-induced, Biogenic, Mass movement, Fluid Flow, Karstic, Anthropogenic) categories. Consistent with Part 1, Part 2 terms are primarily sourced from established literature. The application of Part 2 requires further seabed data and/or contextual information and expert judgement, and is intended to constrain the uncertainty that is inherent to subsurface facies interpretation and prediction to this step. A draft version of Part 2 was the focus of a well-attended ( participants) workshop at the IAG& #8217 s International Seafloor Geomorphology Conference in Malta (July 2022: Nanson et al., 2022). Feedback from that workshop and from the broader community was integrated into a revised version of the report, which will be released early in 2023. & We will demonstrate the application of this method to several worked ex les from coasts, continental shelves and the deep marine, and thereby demonstrate the utility of the two-part approach for mapping the distribution of sedimentary facies that form in these erse marine environments. & Dove, D., Bradwell, T., Carter, G., Cotterill, C., Gafeira Goncalves, J., Green, S., Krabbendam, M., Mellett, C., Stevenson, A., Stewart, H., 2016. Seabed geomorphology: a two-part classification system.& Dove, D., Nanson, R., Bjarnad& #243 ttir, L.R., Guinan, J., Gafeira, J., Post, A., Dolan, M.F.J., Stewart, H., Arosio, R. and Scott, G., 2020. A two-part seabed geomorphology classification scheme:(v. 2). Part 1: morphology features glossary. ecord/4071940#.Y7tURodBxPY& Nanson, R., Arosio, R., Gafeira, J., Dove, D., Guinan, J., McNeil, M., Bjarnad& #243 ttir, L., Dolan, M., Post, A., Nichol, S., 2022. A two-part seabed geomorphology classification scheme: Part 2 Geomorphology - Version 0.9.
Publisher: Elsevier BV
Date: 02-2014
Publisher: Elsevier BV
Date: 09-2014
Publisher: Cold Spring Harbor Laboratory
Date: 18-02-2023
DOI: 10.1101/2023.02.16.528770
Abstract: Marine imagery is a comparatively cost-effective way to collect data on seafloor organisms, bio ersity and habitat morphology. However, annotating these images to extract detailed biological information is time-consuming and expensive, and reference libraries of consistently annotated seafloor images are rarely publicly available. Here, we present the Antarctic Seafloor Annotated Imagery Database (AS-AID), a result of a multinational collaboration to collate and annotate regional seafloor imagery datasets from 19 Antarctic research cruises between 1985 and 2019. AS-AID comprises of 3,599 georeferenced downward facing seafloor images that have been labelled with a total of 615,051 expert annotations. Annotations are based on the CATAMI (Collaborative and Automated Tools for Analysis of Marine Imagery) classification scheme and have been reviewed by experts. In addition, because the pixel location of each annotation within each image is available, annotations can be viewed easily and customised to suit in idual research priorities. This dataset can be used to investigate species distributions, community patterns, it provides a reference to assess change through time, and can be used to train algorithms to automatically detect and annotate marine fauna.
Publisher: Cambridge University Press (CUP)
Date: 24-09-2010
DOI: 10.1017/S095410201000074X
Abstract: The Collaborative East Antarctic Marine Census (CEAMARC) surveys to the Terre Adélie and George V continental margin highlight the requirement for a revised high-resolution bathymetry model that can be used as a spatial tool for improving information on the physical environment of the region. We have combined shiptrack singlebeam and multibeam bathymetry, coastline data, and land and ice sheet topographic data to develop a new regional-scale bathymetry grid, called GVdem (short for George V digital elevation model). The GVdem grid spans an area between 138–148°E and 63–69°S, with a cell pixel size of 0.001-arcdegree ( c . 100 m). The revised digital elevation model is a large improvement over previously available regional-scale grids from the area, and highlights seabed physiographic detail not formerly observed in this part of East Antarctica. In particular, the extent and complexity of the rugged inner-shelf valleys are revealed, and their spatial relationship with large shelf basins and adjacent flat-topped banks. The new grid also reveals further insight into the spatial distribution of the submarine canyons found on the continental slope.
Publisher: Public Library of Science (PLoS)
Date: 17-07-2014
Publisher: Springer Science and Business Media LLC
Date: 07-06-2022
DOI: 10.1038/S41597-022-01366-7
Abstract: The Southern Ocean surrounding Antarctica is a region that is key to a range of climatic and oceanographic processes with worldwide effects, and is characterised by high biological productivity and bio ersity. Since 2013, the International Bathymetric Chart of the Southern Ocean (IBCSO) has represented the most comprehensive compilation of bathymetry for the Southern Ocean south of 60°S. Recently, the IBCSO Project has combined its efforts with the Nippon Foundation – GEBCO Seabed 2030 Project supporting the goal of mapping the world’s oceans by 2030. New datasets initiated a second version of IBCSO (IBCSO v2). This version extends to 50°S (covering approximately 2.4 times the area of seafloor of the previous version) including the gateways of the Antarctic Circumpolar Current and the Antarctic circumpolar frontal systems. Due to increased (multibeam) data coverage, IBCSO v2 significantly improves the overall representation of the Southern Ocean seafloor and resolves many submarine landforms in more detail. This makes IBCSO v2 the most authoritative seafloor map of the area south of 50°S.
Publisher: Copernicus GmbH
Date: 04-03-2021
DOI: 10.5194/EGUSPHERE-EGU21-7751
Abstract: & & In 2016, through a collaboration between marine mapping programmes in Norway, Ireland, and the UK, we published a new classification scheme to aid the characterisation of seabed geomorphology (Dove et al., 2016). The classification scheme was developed to address shared objectives and challenges in seabed mapping, particularly to enable more consistent classification where required. The novel aspect of this framework was the effort to independently describe seabed features according to their observed physical 1-Morphology, and the more subjective interpretation of their origin and evolution (2-Geomorphology). Initial application of the approach within our own groups and externally proved promising, and through the welcome involvement of colleagues from Geoscience Australia, we continued to progress and improve the approach.& & & & We are now within the second phase of the project, which involves the development of glossaries for both parts of the classification scheme. The glossary for part-1 Morphology was recently completed and published (Dove et al., 2020). This glossary includes a revised list of feature names, with definitions and representative diagrams for each feature. Feature definitions are in-part drawn from the International Hydrographic Organization (IHO) guide for undersea feature names, which were modified and augmented with additional terms to ensure the final feature catalogue and glossary encompasses the ersity of morphologies observed at the seabed.& & & & Part-2 Geomorphology glossary is now in development. We anticipate it to be more complicated than the Morphology glossary due to the (often) variable meaning of different terms between different fields and in idual scientists. But as for Part 1, our primary objective is to produce a useful and robust framework (applicable from the coastal zone to the abyss), that minimises duplication and/or ambiguity as much as possible. The Geomorphology glossary will include ex le bathymetry images to add further value.& & & & Dove, D., Bradwell, T., Carter, G., Cotterill, C., Gafeira Goncalves, J., Green, S., Krabbendam, M., Mellett, C., Stevenson, A., Stewart, H. and Westhead, K., Scott, G., Guinan, J., Judge, M., Monteys, X., Elvenes, S., Maeten, N., Dolan, M., Thorsnes, T., Bjarnadottir, L., Ottesen, D., 2016. Seabed geomorphology: a two-part classification system. British Geological Survey, Open Report OR/16/001.& & & & Dove, D., Nanson, R., Bjarnad& #243 ttir, L.R., Guinan, J., Gafeira, J., Post, A., Dolan, M.F.J., Stewart, H., Arosio, R. and Scott, G., 2020. A two-part seabed geomorphology classification scheme:(v. 2). Part 1: morphology features glossary.& &
Publisher: Elsevier BV
Date: 2011
Publisher: Cambridge University Press (CUP)
Date: 17-10-2016
DOI: 10.1017/S0954102016000468
Abstract: This study presents the first analysis of benthic megafauna and habitats from the Sabrina Coast shelf, encompassing a proposed Marine Protected Area. Sea bed imagery indicated an abundant benthic fauna compared to other parts of the Antarctic shelf, dominated by brittle stars, polychaete tubeworms, and a range of other sessile and mobile taxa. The distribution of taxa was related (ρ=0.592, P .001) to variations in water depth, latitude, substrate type and phytodetritus. High phytodetritus cover was associated with muddy/sandy sediments and abundant holothurians and hipods, while harder substrates hosted abundant brachiopods, hard bryozoans, polychaete tubeworms, massive and encrusting sponges, and sea whips. Brittle stars, irregular urchins and anemones were ubiquitous. Variations in substrate largely reflected the distribution of dropstones, creating fine-scale habitat heterogeneity. Several taxa were found only on hard substrates, and their broad regional distribution indicated that the density of dropstones was sufficient for most sessile invertebrates to disperse across the region. The hexactinellid sponge Anoxycalyx joubini and branching hydrocorals exhibited a more restricted distribution, probably related to water depth and limited dispersal capability, respectively. Dropstones were associated with significant increases in taxa ersity, abundance and biological cover, enhancing the overall ersity and biomass of this ecosystem.
Publisher: Copernicus GmbH
Date: 29-01-2021
DOI: 10.5194/TC-2021-8
Abstract: Abstract. Understanding past retreat of Antarctic ice margins provides valuable insight for predicting how ice sheets may respond to future environmental change. This study, based on high resolution multibeam bathymetry from the nearshore region of the Windmill Islands, East Antarctica, reveals a style of retreat that has been rarely observed on the Antarctic margin. A suite of seafloor features record the final retreat stages of a relatively thin, and increasingly fractured tidewater glacier confined within narrow troughs and embayments, forming a suite of features more typical of warm-based ice, but occurring here in a region of cold-based ice with limited surface meltwater production. The pattern of moraines and crevasse squeeze ridges, reveals strong topographic and substrate control on the nature of ice sheet retreat. Topographic control is indicated by fine-scale variability in the orientation and distribution of glacial landforms, which show that the seabed topography influenced the shape of the ice margin, caused deflection of ice flow and led to the separation of flow downstream from topographic highs. The availability of water saturated marine sediments within the troughs and depressions also had a profound effect on the landform record, facilitating the construction of moraines and crevasse squeeze ridges within topographic lows, corresponding to areas of modern sediment accumulation. Surrounding areas of crystalline bedrock, by contrast, acted as sticky spots and lack a well-developed landform record. This seafloor glacial record emphasises the importance of understanding the bed topography and substrate when predicting the nature of ice margin retreat and provides new perspectives for understanding the stability of the East Antarctic margin.
Publisher: Inter-Research Science Center
Date: 15-11-2011
DOI: 10.3354/MEPS09330
Publisher: Geological Society of London
Date: 2016
DOI: 10.1144/M46.172
Publisher: Elsevier
Date: 2012
Publisher: Authorea, Inc.
Date: 25-05-2023
DOI: 10.22541/ESSOAR.168500388.82176124/V1
Abstract: The rapidly melting Totten Glacier of East Antarctica drains a basin containing ~3.5 m sea-level rise equivalent of ice, but the Totten Glacier dynamics and interaction with the Southern Ocean since the Last Glacial Maximum is not well understood. To better understand the response of the glacier to present and future climate changes, an accurate reconstruction of the retreat history of the Totten Glacier is needed. Hence, this study uses a multiproxy approach in analyzing beryllium isotopes, the first such record from this location, and grain size of a sediment core collected from the continental slope adjacent to Totten Glacier. The results, when evaluated together with nearby proxy records, reveal that the initial deglaciation of the Totten Glacier sector of the East Antarctic Ice Sheet began at ~18 ka BP. The rapid deglaciation from ~9 ka BP that followed is assumed to be caused by the intrusion of modified Circumpolar Deep Water to the grounding zone of the Totten Glacier. This intrusion may also be coupled with a weaker Antarctic Slope Current and southward shift of Antarctic easterlies. This result contributes to the body of knowledge regarding the dynamical response of marine-terminating glaciers to climate variability during the last deglaciation.
Publisher: Elsevier BV
Date: 02-2023
No related organisations have been discovered for Alexandra Post.
Start Date: 12-2022
End Date: 12-2025
Amount: $672,000.00
Funder: Australian Research Council
View Funded ActivityStart Date: 08-2021
End Date: 12-2027
Amount: $20,000,000.00
Funder: Australian Research Council
View Funded Activity