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Dependence on water is one of the factors that can determine regional vulnerability in Australia. Climate change is predicted to change rainfall patterns in the Great Barrier Reef (GBR) region, and scarce water resources have the potential to make regional Queensland economies increasingly vulnerable. Understanding which economic sectors depend on water as an input factor helps in understanding sectoral and regional vulnerability, and thus in guiding regional policy aimed at structural change. Using a regional Queensland Input-Output (IO) model, this paper integrates water consumption of the GBR region and then compares monetary IO multipliers with water consumption multipliers. We argue that these IO multipliers can inform regional decision makers about potential future regional vulnerability by taking into account limited water resources. [ABSTRACT FROM AUTHOR]

This paper investigates the use of aesthetic value as a criterion by which the significance of heritage places is assessed. It is argued that current heritage management practice has not engaged with the extensive discourse relating to aesthetics, and therefore confines aesthetics to a particular class and culture, and an inert view of only one of our sensory experiences. Historical records relating to the Great Barrier Reef are used to show how aesthetic appreciation of the area has changed over time.The data suggest that the failure to recognise an aesthetic that is primarily non-visual can lead to changes in landscape and loss of associated value. It also suggests that aesthetic values change rapidly and are influenced by social and technological factors. [ABSTRACT FROM AUTHOR]

The tourism literature offers a number of different themes related to defining and understanding the long stay, independent travel of younger people often, referred to as backpacking. This paper focuses on the two major themes of differences between backpackers and other tourists, and change over time in backpacking, through an examination of survey data collected from tourists to Australia's Great Barrier Reef in 1996, 2001 (prior to the event of September 11) and in 2002 (prior to the Bali Bombing). Backpackers were compared to Other Younger Travellers at each of these three times on a number of variables including travel party, motivations, type of reef trip chosen, and satisfaction. The results supported three main conclusions. Firstly, Backpackers differed from Other Younger Travellers on a number of variables and they retain some of these differences over time. Secondly, both groups changed over time, reflecting impacts of changes in international travel and contexts. Finally, although significant differences continued to exist between the two groups in each time period, over time tourists in the Other Younger Travellers group became more like Backpackers. The study concludes that the concept of backpacking as a rite de passage is worthy of further consideration and research attention. [ABSTRACT FROM AUTHOR]

The Pied Imperial-Pigeon (Ducula bicolor) is a summer migrant to northern Australia, and nests colonially on many islands of the Great Barrier Reef, Queensland. Numbers are perceived to have declined as a result of large-scale shooting in the past and clearing of their mainland feeding grounds. To obtain evidence of any population changes, 1–10 counts were made each breeding season of the evening flight from the mainland to a nesting colony on North Brook Island. The counts began in 1965 and have continued for 50 years. The count represents one individual of a pair that visits the mainland to feed and returns in the evening. In the 1965–66 breeding season, the December count (the count used to compare years) was 4692 birds. Over the following three seasons, numbers declined to a low of 1451 birds in 1968–69; this decline was attributed to shooting of up to 1100 birds at a time. Large-scale shooting stopped in 1968 and was followed by a steady exponential increase (y = 3370.4e0.0908x in numbers over 23 years to 29 818 birds in the 1992–93 season. Numbers have fluctuated between ∼25 000 and 35 000 individuals over the following 18 years. A tropical cyclone of extreme intensity affected the pigeons' breeding site on North Brook Island and their mainland feeding areas in February 2011. In the following breeding season of 2011–12, numbers fell to 5311, but recovered to 21 088 in the 2012–13 season. The dramatic drop in numbers was attributed to the pigeons moving elsewhere for the 2011–12 season. It is predicted that the post-cyclonic number of 21 088 will take 4 years to recover to 30 000. The counts are a simple and somewhat coarse measure of population trends, but provide a population baseline for more sophisticated studies on the movements of pigeons and their responses to long-term changes in habitat and climate. [ABSTRACT FROM AUTHOR]

The claim that the herbicide Diuron in agricultural runoff caused dieback of the grey mangrove (Avicennia marina) in Central Queensland, Australia, has influenced government policies including programs to save the Great Barrier Reef. Several investigations on mangrove dieback in Central Queensland river estuaries have been published during the past decade. However, proof of a causal link between mangrove dieback and Diuron remains inconclusive. This study presents a systematic review of the evidence using Hill's Criteria of Causation. Our review shows that using concentrations of the chemical bound to sediment as a measure for biological availability in either glasshouse or field studies is inappropriate. The appropriate measure is Diuron concentration in solution and this parameter bears no simple relationship to concentration bound to sediment, and is not strongly correlated with mangrove health. Only when the herbicide is applied in experimental investigations at many orders of magnitude higher than measured in rivers has an impact on A. marina been demonstrated. Evidence from field studies suggests burial of pneumatophores, the plant's breathing roots, following flood events is a more likely causal factor in mangrove dieback, whereas any contribution from Diuron remains unproven. [ABSTRACT FROM AUTHOR]

The challenge of developing environmental outcomes acceptable to stakeholders with different values is well documented. Discourse analysis provides insights into how the views of different stakeholders affect decision making. We studied the discourses of key actors associated with the implementation of a Turtle and Dugong Hunting Management Plan developed by Hope Vale Aboriginal community in the Great Barrier Reef World Heritage Area, Australia. The discourses of the environmental managers and community members were very different. Hope Vale people prioritized cultural well-being; the staff of management agencies prioritized biodiversity outcomes. These differences precluded effective outcomes despite considerable investment in hunting management over more than 20 years by both groups. Understanding the discursive terrain within environmental management domains can inform environmental decision making and the implementation of agreed management arrangements, enabling biodiversity objectives and Indigenous cultural aspirations to be met in a socially just, economically viable, and environmentally sustainable way. [ABSTRACT FROM AUTHOR]

Preliminary results of a survey investigating individual well-being of residents in the Great Barrier Reef region of Australia are presented. The well-being factors were grouped into domains of: society, representing family and community issues; ecology, representing natural environment; and economy, dealing with economic issues and provision of services. The relative perceived importance of factors was quantified, allowing for a creation of individual well-being functions. In the society domain, family relations and health were identified as the most important contributors to well-being. Water quality was the ecology domain factor that received highest scores, and health services and income were the most important contributors to the economic domain. The methodological approach used in this study has a potential to integrate ecological, social, and economic values of local people into decision-making processes. The profiles of well-being thus generated would present policymakers with information beyond that available from standard data sources. [ABSTRACT FROM AUTHOR]

There has been considerable effort to set specific, measurable, achievable, realistic and timed (SMART) targets to halt the decline in the quality of water entering the Great Barrier Reef from diffuse sources. Less attention has focused on the assessment of collaborative delivery options needed to meet these targets. This article adapts the SMART criteria to assess partnership needs to deliver voluntary water quality management programs proposed in Queensland's Tully-Murray Water Quality Improvement Plan. This formative assessment enabled us to guide agricultural industry and local government sector focus group discussions. These discussions helped to determine if institutional arrangements adequately considered the specific purpose of proposed management activities, if measures of delivery success were compatible among collaborators, and if delivery costs were fairly distributed and achievable. The assessment also exposed the relevance of proposed management programs to each partner's activities and agendas, and how temporal attributes of partnership design and purpose could maximise the benefits of proposed actions. We suggest that the framework can help other practitioners and researchers to assess systematically how partnerships can be adaptively designed to 'fit' the objectives of integrated water quality management plans. [ABSTRACT FROM AUTHOR]

As one of Australia's iconic tourism attractions and one of the seven natural wonders of the world, the Great Barrier Reef (GBR) is an important economic, social and natural resource for Queensland's Tropical North. However, the long-term prognosis for the health of the reef and by implication, the industries dependent on it, is not positive. So far much attention has focussed on the health and resilience of the reef ecosystem, as a foundation for a resilient tourism industry. In this study we explore how weather conditions have affected the reef experiences of 1000 tourists to the Cairns/Port Douglas region, suggesting that this may also be an important indicator of change on the reef. The results suggest that poor weather has a more pronounced effect on experiences than good weather and reinforce the likelihood that seasickness, cold and wet conditions, reduced water visibility, and difficult snorkelling/diving conditions will reduce overall levels of satisfaction. Poor weather was found to have a direct effect on satisfaction scores, the likelihood that reef and tour expectations were not realised, and lowered perceived value for money. These are important considerations for the reef centred tourism industry that is currently facing strong environment pressures from climate change. [ABSTRACT FROM AUTHOR]

A sedimentological and stratigraphic study of Low Isles Reef off northern Queensland, Australia was carried out to improve understanding of factors that have governed Late Holocene carbonate deposition and reef development on the inner to middle shelf of the northern Great Barrier Reef. Low Isles Reef is one of 46 low wooded island-reefs unique to the northern Great Barrier Reef, which are situated in areas that lie in reach of river flood plumes and where inter-reef sediments are dominated by terrigenous mud. Radiocarbon ages from surface and subsurface sediment samples indicate that Low Isles Reef began to form at ca 3000 y BP, several thousand years after the Holocene sea-level stillstand, and reached sea-level soon after (within ∼500 years). Maximum reef productivity, marked by the development of mature reef flats that contributed sediment to a central lagoon, was restricted to a narrow window of time, between 3000 and 2000 y BP. This interval corresponds to: (i) a fall in relative sea-level, from ∼1 m above present at ca 5500 y BP to the current datum between 3000 and 2000 y BP; and (ii) a regional climate transition from pluvial (wetter) to the more arid conditions of today. The most recent stage of development (ca 2000-0 y BP) is characterised by extremely low rates of carbonate production and a dominance of destructive reef processes, namely storm-driven remobilisation of reef-top sediments and transport of broken coral debris from the reef front and margins to the reef top. Results of the present study enhance existing models of reef development for the Great Barrier Reef that are based on regional variations in reef-surface morphology and highlight the role of climate in controlling the timing and regional distribution of carbonate production in this classic mixed carbonate-siliciclastic environment. [ABSTRACT FROM AUTHOR]

Marine aerosol was collected in September 1998 and July 2005 on the upwind coast of an island at latitude 15°S, about 15 km downwind from the outer edge of the Great Barrier Reef, Australia, and examined by electron microscopy. Exopolymer gels, aggregates of organic particles, marine micro-organisms and fragments of marine life formed a substantial part of the accumulation mode aerosol. Differences in transparency, firmness of outlines and shape of gels and the influence of organic vapours on them, suggested progressive physical and chemical changes with atmospheric residence time. The organic aggregate components had a size distribution remarkably close to that found in similar particles over the central Arctic Ocean peaking at diameters of 30–40 nm. Single components or small groups of these aggregates were found within at least 75% of particles resembling ammonium sulphate in appearance, indicating that aggregates fragmented in the atmosphere. Sea salt was not detected in particles <200 nm diameter unlike many observations showing it to be a major component, a result that was entirely consistent with the Arctic findings. The deduced sequence of changes to particles entering the atmosphere from the ocean is also very similar to that found in the Arctic, suggesting that it is a common pattern over the oceans. That conclusion would require modification of the parametrization of the marine aerosol used in climate models and of possible climate feedback effects. [ABSTRACT FROM AUTHOR]

Tropical cyclones (hurricanes and typhoons) produce high winds that can generate waves capable of damaging coral reefs. As cyclones frequently pass through northeast Australia's Great Barrier Reef (GBR), it is important to understand how the spatial distribution of reef damage changes over time. However, direct measurements of wave damage, or even wave heights or wind speeds, are rare within the GBR. An important factor in estimating whether cyclone damage was possible is the magnitude and duration of high-energy wind and waves. Thus, before the spatio-temporal dynamics of past cyclone damage can be modelled, it is necessary to reconstruct the spread, intensity, and duration of high-energy conditions during individual cyclones. This was done every hour along the track taken by each of 85 cyclones that passed near the GBR from 1969 to 2003, by implementing a cyclone wind hindcasting model directly within a raster GIS using cyclone data available from the Australian Bureau of Meteorology. Three measures of cyclone energy (maximum wind speed—MAX, duration of gales—GALES, and continuous duration of gales—CGALES) were derived from these data. For three cyclones, where field data documenting actual reef damage from cyclone-generated waves were available, the predictive ability of each measure was assessed statistically. All three performed better in predicting reef damage at sites surveyed along the high-energy reef front than those surveyed along the more protected reef back. MAX performed best for cyclone Joy (r 2 = 0.5), while CGALES performed best for cyclones Ivor (r 2 = 0.23) and Justin (r 2 = 0.48). Using thresholds for MAX and GALES obtained via comparison with field data of damage, it was possible to produce a preliminary prediction of the risk of wave damage across the GBR from each of the 85 cyclones. The results suggest that while up to two-thirds of the GBR was at risk from some damage for 30–50% of the time series (∼18 out of 35 years), only scattered areas of the region were at risk more frequently than that. [ABSTRACT FROM AUTHOR]

The potential of fertilized cropping soils (sugarcane, vegetables, fruit trees) in river catchments that drain to the Great Barrier Reef World Heritage Area in northeastern Australia to release soluble phosphorus (P) was assessed using soil chemical tests on typical soils (0–10 cm) collected in 2003. Tests included total P, diagnostic soil P tests, estimates of P buffering, and soluble and redox sensitive soil P. Routine soil P tests proved poor predictors of CaCl2 P (0.005 M). Values&nvge;0.20 for the Mehlich‐3 P saturation ratio separated (P<0.01) lower from higher concentrations of CaCl2 P. The ratio of Mehlich‐3 Fe to [Mehlich‐3 Fe+Mehlich‐3 Al] is offered as a possible simple index of redox sensitive P. Part 1 (Rayment and Bloesch 2006) describes the soil survey in more detail. [ABSTRACT FROM AUTHOR]

Many attempts have been made by ichnologists to match bioerosion traces to their respective tracemakers. This task has been considered difficult, especially for fossil samples. The present study demonstrates that the Australian bioeroding sponge Aka paratypica can generate a cavity similar to the ichnospecies Entobia devonica . The modern sponge and its cavity are redescribed and compared to the fossil boring. A. paratypica has white fistules and soft, mucoid endosomal tissue. Spicules are stout oxeas with often telescoped or mucronate tips. Observed borings of A. paratypica are rounded and cavernous, with canals and apertures radiating from the chambers in all directions. It was noted that the internal openings of such canals are covered with porous nodules, which may act as sieves against larger particles or intruding endofauna. No obvious microsculpturing was observed in the erosion scars. A. paratypica borings are analogous to ancient E. devonica borings, which to date were only known from the fossil record. [ABSTRACT FROM AUTHOR]

Thirty–five species (including eight that are new) of non–didemnid aplousobranch species and 25 phlebobranch (including one new) and stolidobranch species are discussed and a further 42 species in non–didemnid taxa in all suborders are newly recorded. Material was taken by scuba diving in the waters around Kangaroo I. and other southern Australian and Tasmanian locations; and further material was taken by dredge from canyons off the southeastern Continental Slope and from inter–reefal areas in the northern Great Barrier Reef region. The known geographic ranges of many southern Australian species are extended into Tasmanian waters and a new species of Rhopalaea is described from the Tasmanian Canyons. The genera Sigillina and Pseudodistoma are found to be diverse in Australian temperate waters, and they have many characters in common, suggesting a probable phylogenetic relationship that formerly was not recognised. The greatest diversity of species reported is from the vicinity of the northern Great Barrier Reef. Almost without exception these are non–indigenous tropical species often extending into Australian temperate locations where they are sympatric with indigenous species found mainly around the southern half of the continent. Pyura stolonifera has a similar range in temperate Australian waters but appears also to occur on the South African and Chilean coasts in similar habitats and may represent a Gondwana relict. [ABSTRACT FROM AUTHOR]

The southeast Australian continental margin stretches 1500 km north from Bass Strait to the Great Barrier Reef, This part of the Australian margin represents a distinct oceanographic, climatic and geological province. Recent initiatives by the Australian Hydrographic Office, Geoscience Australia and the Environmental Geoscience Group at the University of Newcastle have provided a new digital database of bathymetric soundings and surface-sediment distribution for the southeast Australian margin, This database is used here to provide the first detailed digital 3-D representations of the southeast Australian margin, leading to new morphological classifications and integrated sedimentation models. As a result of its tectonic history of asymmetric passive margin rifting, the continental margin as a whole is narrow, steep and sediment deficient. The shelf can be divided into an inner zone with bedrock cropping out or close to the surface, and an outer zone that represents the top of a Cenozoic sediment wedge. The continental shelf and slope can be classified into a variety of morphological units based on detailed analysis of geometry and slope. These units include a succession of shore-normal zones (shoreface, inner plain, inner and mid-slope, outer plain and continental slope) and a number of local regions (mounds, lobes, tongues, depressions, deltas and bedrock). Sediments are generally siliciclastic in composition on the inner margin and carbonate-rich on the outer margin, reflecting carbonate production at low sea-levels on the outer shelf/continental slope and terrestrial sediment input to the inner shelf. Fine-grained sediments are rare on the shelf north from Port Stephens, and occur draped across the inner and mid-slope further south. Outer shelf carbonate sediments are coarse grained with a patchy distribution related to winnowing by the East Australian Current, The East Australian Current also produces erosional depressions and southward prograding sediment tongues and lobes where it separates from the shelf off Port Stephens, The margin character varies markedly from south to north in terms of fine-sediment distribution, depth to the shelf break and width of the outer shelf. These outer shelf features reflect an inherited palaeotopography from underlying Cenozoic sediment wedges that ore better developed on the southern margin. [ABSTRACT FROM AUTHOR]

A cross-shelf colour zonation is observed in Great Barrier Reef lagoon surficial sediments from 12 to 18°S, with colours tending to lighten from inner to outer shelf. The phenomenon is particularly well defined south of Cairns where four zones occur. The colour zonation appears to reflect the abrupt facies changes that occur in the lagoon. Visual estimates of relative optical lightness for the zones are strongly related to carbonate content, and lightness class boundaries broadly follow carbonate contours, indicating that the mechanisms leading to the colour zones are related to those governing carbonate distribution. [ABSTRACT FROM AUTHOR]

On the Great Barrier Reef shelf, terrigenous sediments adjacent to the Herbert River delta are strongly partitioned within the coastal zone, in common with the regional presence of a terrigenous inner-shelf sediment wedge. Partitioning is primarily controlled by wind-driven currents and waves associated with persistent southeast trade winds. Bottom-return currents provide the likely mechanism for episodic transport of fine-grained sediment in an offshore direction, although modelled bottom-return currents appear incapable of transporting much sediment seawards beyond the 20 m isobath. This depth corresponds to the observed outer limit of the nearshore sediment wedge. [ABSTRACT FROM AUTHOR]

Previous workers have proposed that northward-directed bedload transport dominates the inner shelf of the Great Barrier Reef lagoon. Results from a sediment sampling survey along the 10 m isobath between Bowen and Cape York reveal a series of northward trends of increasing sediment maturity and demonstrate pervasive north-directed sediment transport interacting with a succession of sediment (fluvial) sources. South of the Tully River, the occurrence of limited compositional variability indicates significant mixing on the inner shelf. However, further north the data are highly variable, suggesting that sediment inputs from individual rivers may be retained relatively close to source. This may be related to a greater sediment trapping efficiency within northern embayments and/or by lower net rates of along-shelf transport. [ABSTRACT FROM AUTHOR]

The delivery, flux and fate of terrigenous sediment entering the Great Barrier Reef lagoon has been a focus of recent studies and represents an ongoing environmental concern. Wave-induced bed stress is the most significant mechanism of sediment resuspension in the Great Barrier Reef, and field data and mathematical modelling indicates that the combined effects of short-period wind waves, longer period swell waves, and tidal and wind-driven currents can often exceed the critical bed stress for resuspension. Suspended-sediment concentrations at 20 m water depth indicate resuspension seldom occurs on the middle shelf under normal wave conditions. Non-cyclonic turbidity events are generally confined to the inner shelf. The wave climate in the southern sector of the central Great Barrier Reef lagoon is the most erosive, and resuspension of outer shelf sediments was hindcast for recorded cyclones. Wind-driven, longshore currents are fundamental to the northward movement of sediment, and the annual northward mass flux from embayments undergoing resuspension in the Burdekin region is estimated to be one order of magnitude larger than the mass of sediment introduced by a moderate flood plume. Strong onshore winds are estimated to generate significant three-dimensional bottom return currents on approximately 30–70 days per year, forming a potentially significant offshore-directed sediment flux during high suspended-sediment concentration events on the inner shelf. [ABSTRACT FROM AUTHOR]

The marine sediments of Australia’s continental shelves have been sparsely sampled by geological expeditions. However, there exist many qualitative descriptions of the seabed, made from visual and tactile examination of wet surficial samples, on Royal Australian Navy Hydrographic Office bathymetry charts. The reliability and geological meaning of the visual descriptions do not seem to have been investigated, making their suitability as bottom classifiers unknown. Classification schemes were devised for the descriptions, which are in a symbol form suitable for computer manipulations. The schemes were applied to nearly 5000 descriptions for the Great Barrier Reef lagoon area from Cape Flattery to Whitsunday Islands, where several sediment types are interleaved. The visual descriptions formed a consistent and reliable dataset at regional and smaller scales. Coherent surficial sediment distribution patterns were derived that closely match trends of grainsize distributions in some test areas, but which indicate that the present broadly known patterns for the Great Barrier Reef are in need of revision, particularly in coastal areas and embayments. Broad quantitative correlations were established against grainsize for several key visual descriptions, greatly enhancing their usefulness. The visual descriptions form a database of unique character, more useful than simple grainsize descriptions for many purposes. Sediment charts derived from them match everyday expectations of the in situ appearance and texture of sediments described as mud and sand in the marine environment, whereas various geological grainsize nomenclatures do not. A grainsize triangle is constructed relating the visual descriptions of wet marine surficial sediments to mud, sand and gravel size percentage weights. [ABSTRACT FROM AUTHOR]