Geoscience Australia conducted a survey to measure the benthic nutrient fluxes in Wallis Lake, during February 2003. The objectives were to: 1. measure the nutrient (and other metabolite) fluxes across the sediment-water interface at sites in Pipers Creek, Muddy Creek, Wallis Creek and in the Central Basin of Wallis Lake; 2. describe key processes controlling the nutrient fluxes across the sediment-water interface at each of the four sites; and 3. determine the trophic state and assess the estuarine condition of the four selected sites in Wallis Lake. The results of this recent summertime survey were compared to the observations made during the winter survey conducted in June, 2000. Pipers Creek and muddy Creek were similar in that they were both poorly flushed and close to nutrient discharges. These sites are at risk of experiencing eutrophic conditions. Wallis Creek had a high carbon loading, however the presence of seagrass and high denitrification efficiencies means this site remains in a 'good condition. Similarly, the Central Basin remains in a 'good' condition despite an increase in the carbon loading between winter and summer.

Legacy product - no abstract available

Explaining spatial variation and habitat complexity of benthic habitats from underwater video through the use of maps. Different methodologies currently used to process and analyse percent cover of benthic organisms from underwater video will be addressed and reviewed.

This data package consists of 83 QuickBird satellite images, each in four spectral bands at 2.4 metre spatial resolution. The scene locations are scattered around the Australian coast line. The data was initially acquired as part of a joint project involving Geoscience Australia (GA), CSIRO Land and Water and the University of Tasmania, as part of the National Land and Water Resource Audit (NLWRA). The data are supplied under licence and potential licensees must first seek specific approval from the satellite operator (through GA) before being granted access to the data.

TBA

The Coorong, a shallow coastal lagoon at the mouth of the Murray River, has had a significant decline in water quality over the last 15 years because of reduced freshwater inflows. Salinity has increased throughout the lagoon and currently ranges between 60 and 190 psu depending on the proximity to the Murray Mouth and the season. Although nutrient inflow has been negligible in recent years, the lagoon is considered euthrophic. This study aimed to identify the source of nutrients and the biogeochemical processes that transform them. The key findings were: 1. Groundwater discharge is likely to be an important nutrient source 2. Nitrogen appears to be the nutrient limiting primary production 3. Decomposition of organic matter in the sediments is highly seasonal with much higher rates in the summer.

Keppel Bay is a large shallow coastal embayment adjacent to the mouth of the Fitzroy River, located on the central coast of Queensland. The geomorphology and distribution of sediment in Keppel Bay is complex due to the influence of Late Quaternary sea-level change, relict topography, a geologically diverse catchment, macrotidal hydrodynamic processes and flood events. Seabed morphology, sub-bottom profiles and sediment cores reveal the former path of the Fitzroy River across Keppel Bay and the continental shelf. The palaeo-Fitzroy River flowed west across the shelf to the north of Northwest Reef, a position on the shelf that is now under approximately 60 m of water. With the rise in sea level during the early Holocene, the mouth of the Fitzroy River retreated across the continental shelf and by the middle Holocene it was landwards of its present location, near Rockhampton. During the last few thousand years under a relatively stable sea level, much of the shallow inner region of Keppel Bay has been infilled and the coast has prograded several kilometres. Palaeochannels in the inner section of Keppel Bay have mostly been infilled with sediment, which mainly comprises muddy sand from the Fitzroy River. In the outer bay and on the shelf further west many relict channels have not been infilled with marine sediment indicating that the area is relatively starved of sediment. Sediments in outer Keppel Bay are dominantly relict fluvial deposits that are well sorted with only a minor mud component. Subaqueous dunes in the outer southeastern section of Keppel Bay and Centre Bank indicate that tidal currents and currents associated with the predominant southeasterly winds, appear to be transporting marine biogenic sediments and relict coarse terrigenous sediments into Keppel Bay.

A series of short field surveys in Jervis Bay, New South Wales, were undertaken by Geoscience Australia staff as part of the Surrogates Program in the Commonwealth Environmental Research Facilities (CERF) Marine Biodiversity Hub. The aim of the Jervis Bay field work was to collect accurately co-located physical and biological data to enable research into the utility of physical parameters as surrogates for patterns of benthic biodiversity in shallow soft-sediment habitats. In this report the survey design and sampling methods are described; selected field datasets are mapped and discussed; initial results of the laboratory analysis of seabed samples are presented; and there is a brief description of the upcoming analysis of covariance of the physical and biological datasets. The major outputs of the survey work to date are: 1. High-resolution multibeam acoustic datasets for priority areas along the open coast of Jervis Bay (Beecroft Head to Drum and Drumsticks), within the Jervis Bay National Park; and within the southern bay around Darling Road, and in the bay entrance. 2. High quality underwater video footage of benthic habitats in the Darling Road study area acquired with Geoscience Australia's shallow-water towed-video system. The video was used to characterise benthic habitat types, relief/bedform types, and biota occurrence. Characterisations were collected in real-time along bi-directional (six offshore and four alongshore) towed video transects, and were subsequently processed and mapped into three ArcGIS map layers. 3. A set of broad-scale (bay-wide) widely-spaced, co-located sediment and biotic (infauna) seabed samples from the bay's soft-sediment habitats (polychaete mounds, drift algal beds, sand flats, and sand ripple and wave habitats); 4. Sediment samples for geochemical, biogeochemical and sedimentological analyses. 5. A new acoustic doppler current profiler was successfully trialed, and is now being used to collect seabed current data in the Darling Road study area. 6. A progress report on the survey work was presented at the annual CERF Marine Biodiversity Hub's Annual Science Workshop in October 2008.

This paper describes two studies modelling the potential impacts of extreme events under sea level rise scenarios in two potentially vulnerable coastal communities: Mandurah and Busselton in Western Australia. These studies aim to support local adaptation planning by high resolution modelling of the impacts from climate change.

The Australian National Coastal Vulnerability Assessment (NCVA) has been commissioned by the Federal Government (Department of Climate Change) to assess the risk to coastal communities from climate related hazards including sea-level rise, storm surge and severe wind from tropical cyclones. In addition to an understanding of the impact/risk posed by the current climate, we have also examined the change in risk under a range of future climate scenarios considering a number of periods up to the end of the 21st century. In collaboration with state and local governments and private industry, this assessment will provide information for application to policy decisions for, inter alia, land use, building codes, emergency management and insurance applications. The understanding of coastal vulnerability and risk is derived from a number of factors, including: the frequency and intensity of the hazard(s); community exposure and the relationship with stressors; vulnerability related to socio-economic factors; impacts that result from the interaction of those components; and capacity of communities, particularly vulnerable communities and groups, to plan, prepare, respond and recover from these impacts. These factors and resulting impacts from hazard events are often complex and often poorly known, but such complexity and uncertainty is not an excuse for inaction. Given these limitations, the NCVA has been undertaken using the best information available to understand the risk to coastal areas on a national scale, and to prioritise areas that will require more detailed assessment.