From 1 - 10 / 178
  • <div>The A1 poster incorporates 4 images of Australia taken from space by Earth observing satellites. The accompanying text briefly introduces sensors and the bands within the electromagnetic spectrum. The images include examples of both true and false colour and the diverse range of applications of satellite images such as tracking visible changes to the Earth’s surface like crop growth, bushfires, coastal changes and floods. Scientists, land and emergency managers use satellite images to analyse vegetation, surface water or human activities as well as evaluate natural&nbsp;hazards.</div>

  • Geoscience Australia conducted a survey of benthic nutrient fluxes in Smiths Lake , during February 2003, to gather baseline data for the ongoing management of the waterway by the Great Lakes Council. The objectives were to: 1. measure the nutrient (and other metabolite) fluxes across the sediment-water interface; 2. assess the trophic condition of the two selected sites in Smiths Lake; and 3. describe key processes controlling the nutrient fluxes across the sediment-water interface at each of the two sites. The site in the larger western basin (SL2) had a higher carbon loading than the site in the smaller eastern basin (SL1). As a result, denitrification efficiencies have been reduces and more nitrogen retained in the system. Given the long residence time of the water in Smiths Lake, there is a threat of deteriorating water quality if nutrient inputs from the catchment are increased.

  • This report describes the investigations into the coastal creek system conducted within the Fitzroy agricultural contaminants project. Before this work started there had been only a limited data acquisition on the water quality parameters in several of the coastal creeks carried out by the Queensland Environmental Protection Agency (EPA). These data are a valuable augmentation to the data collected under Coastal CRC auspices. We briefly outline the consolidated dataset, draw qualitative conclusions from it, and develop a conceptual model reflecting the interacting processes. These analyses are then the starting point for the development of a quantitative characterisation of the role of the coastal creeks in the biogeochemistry of Keppel Bay.

  • In recent years there has been concern that catchment-derived nutrients and sediments discharged by rivers into the lagoon of the Great Barrier Reef are having a deleterious impact on near-shore reef ecosystems. On average, the Fitzroy River delivers the second largest quantity of these materials to the lagoon after the Burdekin River. The Fitzroy Agricultural Contaminants Project (AC), which is a Coastal CRC project, included amongst its aims the development of an understanding of the fate and impact of these agricultural contaminants (nutrients and sediments) within the Fitzroy Estuary-Keppel Bay system.

  • In this study of the beach-ridge plain at Keppel Bay, on the central coast of Queensland, we examine ridge morphology, sediment texture and geochemistry. We build a detailed chronology for the ridge succession using the optically stimulated luminescence (OSL) dating method. Although our interpretations are preliminary, our results suggest that significant changes have occurred in the rate of shoreline accumulation of sediment, catchment sediment source areas, and that there have been minor falls in relative sea level.

  • Permeable, sandy sediments cover most of the continental shelf. The important role of pore-water advective flow on biogeochemical processes in these sediments has been highlighted in recent studies. Such flow can be driven by wave-action, water-density and interactions between topography and bottom currents, in addition to biological activity, and can create spatially complex and highly dynamic benthic environments in which processes vary on timescales ranging from minutes to months. It is well known that the patchiness of soft sediment (organic matter/bacteria, particle diversity, redox) is likely to be a major determinant of species diversity, but previous studies have not specifically defined patches based on a range of biologically-relevant physico-chemical variables, nor observed how patches change across time. This study, as part of the Surrogates Program in the Commonwealth Environmental Research Facilities Marine Biodiversity Hub, investigated temporal changes in the geochemistry, physical sediments and infauna of sandy sediments in Jervis Bay at two times.

  • Fresh groundwater stored in Australian coastal aquifers constitutes an important resource for humans and the natural environment. However, many Australian coastal aquifers are vulnerable to seawater intrusion the landward encroachment of seawater into coastal aquifers. This report is one technical assessment of the National Seawater Intrusion Project, aimed at characterising current and future seawater intrusion vulnerability of Australian coastal aquifers. This report outlines the development of a typological framework to categorise coastal aquifers and assist in their assessment of vulnerability. The report includes a characterisation of the different hydrogeological and climatic settings of Australia's coastal aquifer. Using public and confidential information, simplified cross-sectional conceptual models of case study areas were developed and aquifer parameters were tabulated for 28 case study areas (CSAs). Key hydrogeological characteristics are analysed and tabulated for use in other aspects of the overall vulnerability assessment.

  • Note that this Record has now been published as Record 2014/050, GeoCat number 78802