IMAS Data Manager
Type of resources
Topics
Keywords
Contact for the resource
Provided by
Years
-
Carbon and nitrogen isotope data for J. edwardsii lobsters from eight sites in SE Australia.
-
This dataset contains the input and output data for an extended optimum multiparameter analysis (eOMP). Input data for parameters are given (temperature, salinity, oxygen, nitrate, phosphate and silicate), as obtained from the cited CSIRO open access CTD bottle data for the 2018 SR3 occupation. Output parameters are the proportional contribution of 8 water masses that were defined in the eOMP analysis. The output remineralization estimate, Delta-O, is also given. All data are referenced to depth and geographical position (latitude, longitude) from corresponding CTD bottle data. The eOMP used here was configured following Pardo et al. (2017). Details on the equations, parameterization and end-members that characterize the regional oceanography can also be found in the Supplementary Materials of Traill et al. (2023), including the robustness of the OMP analysis and the uncertainties of both the SWTs’ contributions and the ΔO parameter (Sections S1.2 and S1.3, Table S1, Table S2, Table S3).
-
Invasive mammal eradications are commonplace in island conservation. However, post-eradication monitoring beyond the confirmation of target species removal is rarer. Seabirds are ecosystem engineers on islands and are negatively affected by invasive mammals. Following an invasive mammal eradication, the recovery of seabird populations can be necessary for wider ecosystem recovery. Seabirds fertilise islands with isotopically heavy nitrogen, which means nitrogen stable isotope analysis (δ15N) could provide a useful means for assessing corresponding change in ecosystem function. We quantified decadal changes in δ15N on eight temperate New Zealand islands subject in pairs to distinct mammal invasion and seabird restoration histories: invaded, never-invaded, invader-eradicated and undergoing active seabird restoration. First, we investigated long-term changes in δ15N values on individual islands. Second, we used a space for time analysis to determine if δ15N levels on islands from which invaders had been removed eventually recovered to values typical of never-invaded islands. On each island soil, plants (Coprosma repens, C. robust and Myrsine australis) and spiders (Porrhothelidae) were sampled in 2006/07 and 2022 allowing δ15N change on individual islands over 16 years to be assessed. Combined, the samples from invader-eradicated islands provided a 7 – 32 year post-eradication dataset. Change in δ15N was only detected on one island across the study period, following the unexpected recolonisation of seabirds to an invaded island. Invader-eradicated islands generally had higher δ15N values than invaded islands however, they were still lower than never-invaded islands and there was no trend in δ15N with time since eradication. This, and the measurable increase in δ15N following seabird recolonisation on one island, may suggest that δ15N change occurs rapidly following invader-eradication, but then slows, with δ15N values staying relatively constant in the time period studied here. Isotope and seabird population studies need to be coupled to ascertain if plateauing in δ15N reflects a slowing of seabird population growth and subsequent basal nutrient input, or if the baseline nutrients are entering the ecosystem but then not propagating up the food web.
-
Five subsections of Antarctic ice cores were used to create a new methodology for analyzing microplastics in sea ice.
-
This data record contains findings from bottom trawl dredging by the FV Southern Champion voyage SC26 (April to May 2003). The petrographic, geochemical and geochronological data provided here was organised by Prof. Pat Quilty and Dr. Trevor Falloon. Further research is underway to characterise dredged granites and gneisses as part of a PhD project facilitated by the Institute for Marine and Antarctic Studies (IMAS), University of Tasmania. The metadata record will be updated to reflect further publications related to this dataset.
-
Data to accompany publication on wild diet of southern rock lobster on the east coast of Tasmania. In this study we collected 64 lobsters and analysed the diet of each individual using stomach contents, stable isotope analysis and DNA identification of prey species in faecal samples.
-
Parks Australia - Our Marine Parks Grants Round 2 Project: Nearshore marine habitat mapping of the Norfolk Marine Park (Grant Activity ID: 4-FIZ391E) The Norfolk Marine Park is the is the eastern-most Park in the Temperate East Network of Australian Marine Parks, located between the NSW coast and Norfolk Island. The Park encompasses 188,444 km² of ocean and ranges in depth from 0 m at the Norfolk Island high tide mark to more than 5,00 m off the edge of the Norfolk Ridge. The Park includes two key ecological features – the Norfolk Ridge, and the Tasman Front and associated eddy field – both of which are valued for their high productivity, aggregations of marine life, biodiversity, and endemism. Norfolk Marine Park supports a range of species, including those listed as threatened under the Environment Protection and Biodiversity Conservation (EPBC) Act (1999), and contains Biologically Important Areas for breeding, foraging, and migration of seabirds, marine turtles, and humpback whales. The objective of this project was to create the first marine habitat map for the nearshore shallow water surrounding Norfolk, Nepean, and Phillip Islands. This was conducted in collaboration with Norfolk residents to provide local knowledge input and to ground-truth the remotely-sensed habitat mapping. This high-level habitat map will be used for planning purposes, development applications, and EPBC Act referrals within the nearshore waters of the Norfolk Marine Park, where no specific zoning for recreational and commercial activities currently exists. The map provides a basis for any ongoing citizen-science-driven marine habitat impact and condition assessments, ecosystem monitoring, and to provide the Norfolk Island residents with ownership of any future zoning planning. The map can be further refined as more detailed information becomes available from subject matter experts in the future.
-
'Weather@home ANZ' is a global citizen science distributed computing project being run as part of the Oxford-based 'weather@home' project, which is part of 'climateprediction.net'. In this experiment, a detailed limited area (regional) climate model is embedded within the less detailed 'driving' global model. This higher-resolution regional model is able to tell us in unprecedented detail about potential changes to patterns of weather as climate changes. In the initial 'weather@home' experiment launched in 2010, the project team released this regional modelling capability for three regions: Europe, Southern Africa and the Western USA. This capability has been extended to other regions around the world and the first such new region to be developed was the Australasian region encompassing Australia, New Zealand and surrounding areas, which was launched to the public in 2014. This particular part of the project - 'weatherathome ANZ' - has received support from the University of Oxford (U.K.), the U.K. Met. Office, the Universities of Melbourne and Tasmania (Australia), the Tasmanian Partnership for Advanced Computing and the New Zealand National Institute for Water and Atmospheric Research (NIWA). 'weather@home' has also been supported by Microsoft Research.
-
The aim of this project was to estimate the iron recycling and export potential of Antarctic krill faecal pellets. To determine this, we firstly determined the sinking rate of the faecal pellets, characteristics which may influence the sinking rate (e.g., density, length and diameter), and then determined the portion of the total iron in the faecal pellets that is leached over a 12 h period under a continuous flow of seawater. The data sets that can be accessed here are: 1. Faecal pellet characteristics, including the raw and analysed data 2. The dry weight and length of faecal pellets used for total Fe estimation 3. Raw and final iron leachate data
-
At the inception of our project, no study had examined particle fluxes in the Subantarctic Zone (SAZ) of the Southern Ocean, despite the fact that the SAZ represents a large portion of the total area of the Southern Ocean, serve as a strong sink for atmospheric (~1G t C yr-1 [Metzl et al., 1999]), and is central to hypotheses linking particle fluxes and climate change [Francois et al., 1997; Kumar et al., 1995; Sigman et al., 1999]. The SAZ serves as an interface between the cold nutrient-rich waters to its south and the nutrient-depleted subtropical gyres to its north. SAZ upper layers are marked by a thick layer of relatively homogenous Subantarctic Mode Water (SAMW), which overlies Antarctic Intermediate Water (AAIW). Both water masses are subducted northward beneath the subtropical gyres. Thus particles leaving the surface in these regions contribute to carbon redistribution via both the fraction that reaches the deep sea by settling and the fraction that is remineralized within SAMW or AAIW and subsequently subducted. The SAZ exhibits surface water carbon dioxide partial pressures well below atmospheric equilibrium, but PFZ waters are closer to atmospheric equilibrium in this sector [Metal et al., 1999; Poppet al., 1999]. The relative physical and biological contributions to these carbon dioxide partial pressure variations are unclear, but it is important to determine them because physical and biological carbon dioxide transfers are expected to show different responses to climate change [ Matear et al., 1999; Sarmiento and LeQuere, 1996]. For these reasons we focused on the SAZ and, for comparative purposes, on the PFZ to its south. We measured particle fluxes using moored sinking particle traps at three sites in the SAZ, in the PFZ, and beneath the Subantarctic Front (SAF), which separates them. This record describes particle flux data collected between 2000 and 2001. The NetCDF data contains the following variables. Please note not all variables are supplied in all files, specifically there are not uncertainty estimates and no quality control flags for this data.
IMAS Metadata Catalogue