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  • The impact of seismic surveys on the catchability of marine fish is a contentious issue, with claims that seismic surveys may negatively affect catch rates. However little empirical evidence exists to quantify the impacts or determine potential causes. In this study, we used a 2-D seismic survey in the Gippsland Basin, Bass Strait, Australia in April 2015 as an opportunity to quantify fish behaviour (field-based) and commercial fisheries catch (desktop study) across the region before and after airgun operations. Three species found in abundance (gummy shark, swell shark, tiger flathead) were acoustically tagged and released within one of two acoustic arrays (experimental and control zone) and monitored before, during and after the seismic survey. In the field study, only 35% of the gummy sharks and 30% of the swell sharks were subsequently detected two days after release, although various individuals returned sporadically over the period of monitoring including during the seismic survey operations. Behaviour consistent with a possible response to the seismic survey operations was restricted to flathead which increased their swimming speed during the seismic survey period and changed their diel movement patterns after the survey. We also investigated the potential impacts of the seismic survey on catch rates using Commonwealth fisheries logbook data from Jan 2012 – Oct 2015. Fifteen species and two gear types (Danish seine, gillnet) were modelled to examine differences in catch rates before and after the seismic survey. The catch rates in the six months following the seismic survey were different than predicted in nine out of the 15 species examined, with six species (tiger flathead, goatfish, elephantfish, boarfish, broadnose shark and school shark) showing increases in catch following to the seismic survey, and three species (gummy shark, red gurnard, sawshark) showing reductions. Overall, we found little evidence consistent with behavioural or catch rate changes induced by the seismic survey in the targeted species, although behavioural data were limited because many sharks left the acoustic receiver array prior to the commencement of the seismic survey. <b>Citation:</b> Barry Bruce, Russ Bradford, Scott Foster, Kate Lee, Matt Lansdell, Scott Cooper, Rachel Przeslawski, Quantifying fish behaviour and commercial catch rates in relation to a marine seismic survey,<i> Marine Environmental Research</i>, Volume 140, 2018, Pages 18-30, ISSN 0141-1136. https://doi.org/10.1016/j.marenvres.2018.05.005.

  • Unlike land based environments, relatively little is known about what the seafloor around Australia looks like or has living on it. Geoscience Australia undertakes a range of marine surveys to improve the understanding and the management of Australia's marine environments. One component of the research involves the use a towed video system to directly observe coastal and deep sea environments and identify what habitats occur there and the organisms that live there. In some regions these surveys build on existing knowledge, but in many areas, particularly in deep offshore sites, these devices provide the first images of the seafloor. This data package includes towed video and still images acquired on GA surveys from 2007 onwards. Between 2007 and 2013, this included 21 marine surveys (including Antarctic waters). Using a winch on the ship, the video system is lowered to 1-2 metres above the seafloor and then towed along at 1-2 knots. This speed and altitude allows the video camera to record sharp images of the seafloor while covering distances of up to 1-2 km. Video footage is sent up a cable to the ship so it can be viewed in real time. The hours of footage collected on the seafloor provide a wealth of information about the geological features, habitats and life forms occurring throughout Australia's marine jurisdiction.

  • Phase two of the China Australia Geological Storage of CO2 (CAGS2) project aimed to build on the success of the previous CAGS project and promote capacity building, training opportunities and share expertise on the geological storage of CO2. The project was led by Geoscience Australia (GA) and China's Ministry of Science and Technology (MOST) through the Administrative Centre for China's Agenda 21 (ACCA21). CAGS2 has successfully completed all planned activities including three workshops, two carbon capture and storage (CCS) training schools, five research projects focusing on different aspects of the geological storage of CO2, and ten researcher exchanges to China and Australia. The project received favourable feedback from project partners and participants in CAGS activities and there is a strong desire from the Chinese government and Chinese researchers to continue the collaboration. The project can be considered a highly successful demonstration of bi-lateral cooperation between the Australian and Chinese governments. Through the technical workshops, training schools, exchange programs, and research projects, CAGS2 has facilitated and supported on-going collaboration between many research institutions and industry in Australia and China. More than 150 experts, young researchers and college students, from over 30 organisations, participated in CAGS2. The opportunity to interact with Australian and international experts at CAGS hosted workshops and schools was appreciated by the participants, many of whom do not get the opportunity to attend international conferences. Feedback from a CAGS impact survey found that the workshops and schools inspired many researchers and students to pursue geological storage research. The scientific exchanges proved effective and often fostered further engagement between Chinese and Australian researchers and their host organisations. The research projects often acted as a catalyst for attracting additional CCS funding (at least A$700,000), including two projects funded under the China Clean Development Mechanism Fund. CAGS sponsored research led to reports, international conference presentations, and Chinese and international journal papers. CAGS has established a network of key CCS/CCUS (carbon capture, utilisation and storage) researchers in China and Australia. This is exemplified by the fact that 4 of the 6 experts that provided input on the 'storage section of the 12th Five-Year plan for Scientific and Technological Development of Carbon Capture, Utilization and Storage, which laid out the technical policy priorities for R&D and demonstration of CCUS technology in China, were CAGS affiliated researchers. The contributions of CAGS to China's capacity building and policy CCUS has been acknowledged by the Chinese Government. CAGS support of young Chinese researchers is particularly noted and well regarded. Letters have been sent to the Secretary of the Department of Industry and Science and to the Deputy CEO of Geoscience Australia, expressing China's gratitude for the Australian Government's support and GA's cooperation in the CAGS project.

  • This resource contains sediment data for the Oceanic Shoals Commonwealth Marine Reserve (CMR) in the Timor Sea collected by Geoscience Australia during September and October 2012 on RV Solander (survey GA0339/SOL5650). Seabed sediment samples were collected from four survey areas by either a Smith McIntyre grab or box corer at 62 stations, divided between Area 1 (n=22), Area 2 (n=17), Area 3 (n=21) and Area 4 (n=2). The Oceanic Shoals Commonwealth Marine Reserve survey was undertaken as an activity within the Australian Government's National Environmental Research Program Marine Biodiversity Hub and was the key component of Research Theme 4 - Regional Biodiversity Discovery to Support Marine Bioregional Plans. Hub partners involved in the survey included the Australian Institute of Marine Science, Geoscience Australia, the University of Western Australia, Museum Victoria and the Museum and Art Gallery of the Northern Territory. Data acquired during the survey included: multibeam sonar bathymetry and acoustic backscatter; sub-bottom acoustic profiles; physical samples of seabed sediments, infauna and epibenthic biota; towed underwater video and still camera observations of seabed habitats; baited video observations of demersal and pelagic fish, and; oceanographic measurements of the water column from CTD (conductivity, temperature, depth) casts and from deployment of sea surface drifters. Further information on the survey is available in the post-survey report published as Geoscience Australia Record 2013/38 (Nichol et al. 2013).

  • As part of the controlled release experiments at the Ginninderra test site, geophysical surveys have been acquired using electromagnetic techniques at a range of frequencies. The primary objective was to assess whether these could provide insight into the soil structure at the site, give guidance as to where to monitor for leakage, and provide additional information that may explain the observed sub-surface and surface CO2 migration behavior. A secondary objective was to assess whether CO2 leaks could be located based on secondary impacts such as drying of the soil profile. Ground penetrating radar surveys were taken during the second release experiment (October - December 2012). Different frequency shielded antennas were trialled in order to optimize the signal. Two surveys were conducted: one baseline survey prior to CO2 release and another during the release experiment. The GPR results show a reduction in range and clear reflections to the west indicating that clay was present. To the east we see clearer reflections from sand layers and the water table. These observations corresponded with larger scale sub-surface soil features determined from EM31 and EM38 electromagnetic surveys. Application of these geophysical surveys for CO2 leak detection and monitoring design are discussed. Paper for CO2CRC Research Symposium 2013

  • Geoscience Australia defines a borehole as the generalized term for any narrow shaft drilled in the ground, either vertically or horizontally, and would include Mineral Drillholes, Petroleum Wells and Water Bores along with a variety of others types, but does not include Costean, Trench or Pit. For the purposes of a Water Well as defined by Groundwater ML v1.0, the dataset has been restricted to onshore Australian boreholes only, and bores that have the potential to support assessment of groundwater resources, within a Bioregional Assessment.

  • This report provides the first comprehensive assessment of geomorphological and geological features of the Great Barrier Reef (GBR) whose intrinsic characteristics represent elements of the Outstanding Universal Value (OUV) of the Great Barrier Reef World Heritage Area (GBRWHA). Specific examples of these features are described and an initial assessment made of the environmental pressures that they currently or in the future may experience. Importantly, the information compiled in this report improves our knowledge of an important set of physical and biophysical features in the GBRWHA with key natural heritage values and thereby has the potential to better inform the conservation and management of this unique region.

  • Normalised Difference Vegetation Index (NDVI) was used to map vegetation with potential access to groundwater in the basalt provinces in the Upper Burdekin. NDVI is widely used to infer vegetation density and/or vigour. Several studies (e.g. Barron et al., 2014; Gou et al., 2015; Lv et al., 2013) have used NDVI to identify groundwater-dependent vegetation (GDV) based on the hypothesis that during dry seasons or extended dry periods, soil moisture progressively becomes depleted. Under these conditions, GDV are expected to exhibit minimal or no reduction in condition relative to vegetation subject to the same conditions that do not have access to groundwater.<br> <b>References: </b><br> Barron OV, Emelyanova I, Van Niel TG, Pollock D and Hodgson G (2014) Mapping groundwater-dependent ecosystems using remote sensing measures of vegetation and moisture dynamics. Hydrological processes 28(2), 372-385. Doi: 10.1002/hyp.9609; Gou S, Gonzales S and Miller GR (2015) Mapping Potential Groundwater-Dependent Ecosystems for Sustainable Management. Ground Water 53(1), 99-110. Doi: 10.1111/gwat.12169; Lv J, Wang X-S, Zhou Y, Qian K, Wan L, Eamus D and Tao Z (2013) Groundwater-dependent distribution of vegetation in Hailiutu River catchment, a semi-arid region in China. Ecohydrology 6(1), 142-149. Doi: 10.1002/eco.1254.

  • ARR is a series of national guidelines and datasets fundamental to flood estimation. The work is being completed by Engineers Australia and funded by the Australian Government through the National Flood Risk Information Project at Geoscience Australia. This flyer is for promoting the revision of ARR at the Hydrology & Water Resources Symposium (HWRS 2015) in Hobart in December 2015.

  • In this study, we aim to identify the most accurate methods for spatial prediction of seabed gravel content in the northwest Australian Exclusive Economic Zone. We experimentally examined: 1) whether input secondary variables affect the performance of RFOK and RFIDW, 2) whether the performances of RF, SIMs and their hybrid methods are data-specific, and 3) whether model averaging improves predictive accuracy of these methods in the study region. For RF and the hybrid methods, up to 21 variables were used as predictors. The predictive accuracy was assessed in terms of relative mean absolute error and relative root mean squared error based on the average of 100 iterations of 10-fold cross validation. In this study, the following important findings were achieved: - the predictive errors fluctuate with the input secondary variables; - the existence of correlated variables can alter the results of model selection, leading to different models; - the set of initial input variables affects the model selected; - the most accurate model can be missed out during the model selection; - RF, RFOK and RFIDW prove to be the most accurate methods in this study, with RFOK preferred; and these methods are not data-specific, but their models are, so best model needs to be identified; and - Model averaging is clearly data-specific. In conclusion, model selection is essential for RF and the hybrid methods. RF and the hybrid methods are not data-specific, but their models are. RFOK is the most accurate method. Model averaging is also data-specific. Hence best model needs to be identified for individual studies and application of model averaging should also be examined accordingly. RF and the hybrid methods have displayed substantial potentials for predicting environmental properties and are recommended for further test for spatial predictions in environmental sciences and other relevant disciplines in the future. This study provides suggestions and guidelines for improving the spatial predictions of biophysical variables in both marine and terrestrial environments.