<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>

This dataset maps the geomorphic habitat environments (facies) for 88 Tasmanian coastal waterways. The classification system contains 11 easily identifiable and representative environments: Barrier/back-barrier, Bedrock, Central Basin, Channel, Coral, Flood- and Ebb-tide Delta, Fluvial (bay-head) Delta, Intertidal Flats, Rocky Reef, Saltmarsh/Saltflat, Tidal Sand Banks (and Unassigned). These types represent habitats found across all coastal systems in Australia. The majority of near pristine estuaries in Tasmania are located in the south and west of the State and on Cape Barren Island, according to the Department of Primary Industries, Water and Environment.

This dataset maps the geomorphic habitat environments (facies) for 213 Queensland coastal waterways. This version of the dataset includes 73 newly mapped estuaries, classified as 'Near pristine'. The classification system contains 12 easily identifiable and representative environments: Barrier/back-barrier, Bedrock, Central Basin, Channel, Coral, Flood- and Ebb-tide Delta, Fluvial (bay-head) Delta, Intertidal Flats, Mangrove, Rocky Reef, Saltmarsh/Saltflat, Tidal Sand Banks (and Unassigned). These types represent habitats found across all coastal systems in Australia. Southern and central Great Barrier Reef lagoon coasts have a broad spectrum of river, tide and wave- dominated estuaries.

Monitoring changes in the spatial distribution and health of biotic habitats requires spatially extensive surveys repeated through time. Although a number of habitat distribution mapping methods have been successful in clear, shallow-water coastal environments (e.g. aerial photography and Landsat imagery) and deeper (e.g. multibeam and sidescan sonar) marine environments, these methods fail in highly turbid and shallow environments such as many estuarine ecosystems. To map, model and predict key biotic habitats (seagrasses, green and red macroalgae, polychaete mounds [Ficopamatus enigmaticus] and mussel clumps [Mytilus edulis]) across a range of open and closed estuarine systems on the south-west coast of Western Australia, we integrated post-processed underwater video data with interpolated physical and spatial variables using Random Forest models. Predictive models and associated standard deviation maps were developed from fine-scale habitat cover data. Models performed well for spatial predictions of benthic habitats, with 79-90% of variation explained by depth, latitude, longitude and water quality parameters. The results of this study refine existing baseline maps of estuarine habitats and highlight the importance of biophysical processes driving plant and invertebrate species distribution within estuarine ecosystems. This study also shows that machine-learning techniques, now commonly used in terrestrial systems, also have important applications in coastal marine ecosystems. When applied to video data, these techniques provide a valuable approach to mapping and managing ecosystems that are too turbid for optical methods or too shallow for acoustic methods.

Legacy product - no abstract available

The variability in the inherent optical properties along an estuary-coast-ocean continuum in tropical Australia has been studied. The study area, the Fitzroy Estuary and Keppel Bay system, is a shallow coastal environment (depth < 30 m) with highly turbid waters in the estuary and blue oceanic waters in the bay and subject to macrotides. Biogeochemical and inherent optical properties (IOPs) were sampled in the near-surface layer spatially and across the tidal phase during the dry season. These determinations included continuous measurements of spectral absorption, scattering and backscattering coefficients, together with discrete measurements of spectral absorption coefficients of phytoplankton, nonalgal particles and colored dissolved organic matter, and concentrations of phytoplankton pigments and suspended matter. Because of a large variability in the characteristics of the water components on short spatial and temporal scales, we observe a large variability in the associated optical properties. From the estuary to the bay, particle scattering and dissolved absorption decreased by 2 orders of magnitude, and nonalgal particle absorption decreased by 3 orders of magnitude. We also observed a strong variability in particle single scattering albedo and backscattering efficiency (by a factor of 6) and in specific IOPs (IOPs normalized by the relevant constituent concentration) such as suspended matter-specific particle scattering and chlorophyll-specific phytoplankton absorption. Superimposed on this strong spatial variability is the effect of the semidiurnal tide, which affects the spatial distribution of all measured properties. These results emphasize the need for spatially and temporally adjusted algorithms for remote sensing in complex coastal systems.

Bathymetry is the study and mapping of the sea floor. It involves obtaining measurements of the depth of the ocean and is the equivalent to mapping topography on land. Bathymetric data is collected in multiple ways: 1. Satellite data can be used to produce maps showing general features over a large area at low resolution. Satellite altimetry measures the height of the ocean surface. If there are hills/mountains on the sea floor, the gravitational pull around that area will be greater and hence the sea surface will bulge. This measurement can be used to show where the seafloor is higher, and this can be used to produce maps showing general features over a large area at low resolution. 2. Single beam echosounders produce a single line of depth points directly under the equipment. These measurements are usually made while a vessel is moving to identify general sea floor patterns and/or schools of fish. 3. Equipment that captures swathes of data by acquiring multiple depth points in each area, such as multibeam echosounders (or swath echosounders) and airborne laser measurements (LADS). These datasets are very high resolution, with data down to better than one metre accuracy. This bathymetry dataset is a collection of singlebeam data sourced from seismic navigation lines, multibeam data, satellite and LADS data acquired by GA and by other government and non-government agencies.

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.

The Fitzroy catchment is the largest Queensland catchment discharging to the Great Barrier Reef (GBR) lagoon. Sediments and nutrients together with anthropogenic pollutants originating upstream in the catchment are discharged from the Fitzroy River via the Fitzroy Estuary (FE) and ultimately into Keppel Bay (KB). The estuary and the bay act as natural chemical reactors where the materials delivered undergo chemical and physical transformations before some are deposited and stored in the growing deltaic and beach areas, with the remainder transported eastward to the southern zone of the GBR lagoon.