North Queensland Coast Research Articles

The importance of supervisory and organisational awareness of the risks for an early career natural hazard researcher with personal past-disaster experience

Higher education students are advised that research must be objective, focusing on research outcomes and a strict set of criteria upon which the student will be examined. Yet, for those undertaking natural hazard research, this advice is tested, particularly if the student themselves were also impacted by the same natural hazard. Such was the experience of this author. This paper reflects on the author's personal natural hazard experiences, and the drivers that resulted in the pursuit of a higher education degree which involved the phenomenological investigation of the impact of these disasters on the lives of those residing in isolated exposed locations on the Far North Queensland coast in Australia. The aim of this paper is to highlight the importance of supervisors and organisations charged with ensuring the students well-being understand why a student wishes to pursue emotion-charged research. The article concludes with recommendations that supervisors and Ethics Committees focus not only on the risks to participants, but also to the students themselves, by ensuring they also consider the student's own past-disaster experiences.

'Reality' Fiction and the Great Barrier Reef

Di Morrrissey is one of Australia's most widely-read writers of popular fiction. Her special twist on the mode is to choose a particular setting and research it deeply, often living in the area for a time. Her thirteenth novel, The Reef (Sydney: Pan Macmillan, 2004) is set on Branch Island "named because it was an island sprouting right from a limb of the Great Barrier reef (135), somewhere east of "Headland Bay" which, when described (133-34) suggests a hybrid Cairns/Cardwell/Port Douglas, actual towns spread along Australia's North Queensland coast, which is paralleled by the Great Barrier Reef.

Testing versions of the Bruun rule for low energy macro-tidal tropical beaches against a theoretical late Holocene sea-level high-stand and beach ridge evidence of late Holocene beach faces

Kerans, A.J., and Cartwright, N., 2016. Testing versions of the Bruun rule for low energy macro-tidal tropical beaches against a theoretical late Holocene sea-level high-stand and beach ridge evidence of late Holocene beach faces. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 740–744. Coconut Creek (Florida), ISSN 0749-0208.Significant evidence of late Holocene beach faces is presented in beach ridges along the North Queensland coast between Mackay and the Daintree region. The ages of these ridges has in some cases been dated giving confidence that the rearmost ridges are the result of a combination of cyclone activity and a late Holocene sea level high-stand. The height of this high-stand is the subject of debate, however the level may be confidently predicted through careful and extensive measurement of relict oyster beds in the region. Using pre-existing beach ridge research together with existing and new measurements of oyster beds on Magnetic Island, North Queensland a value for the late Holocene sea level high-stand is proposed which can be compared to the position of the coast on certain beaches during this period. These measurements are a good basis to test the applicability of the Bruun rules and some proposed modifications for the low energy beach systems of tropical North Queensland. This paper firstly examined the late Holocene sea level evidence stored in relict oyster beds and from that proposes a sea level to be used in the analysis. This sea level is then used to test the Bruun rule and variants and examine the differences between dated Holocene beach faces and the recession predicted by these models.

Community divergence in a tropical forest following a severe cyclone

Cyclones are relatively infrequent, may cause massive and widespread disturbance to tropical regions, and are recognized as important determinants of the structure of tropical rainforest communities. Climate change scientists predict that the intensity of cyclones will increase in the future; understanding the long-term implications of these major disturbances for tropical forest composition and structure will be vital in anticipating and adapting to future changes and impacts. We established a long-term monitoring site in a rainforest area impacted by severe tropical Cyclone Larry which crossed the North Queensland coast of Australia in March 2006. We monitored recruitment, growth and mortality of nearly 17 000 seedlings in 90 quadrats across the study area for almost 5 years following the cyclone and measured the impact of variation in cyclone disturbance and debris load on community diversity, composition and dispersion as the forest recovered. We show that the level of structural disturbance sustained by the forest has a strong and immediate influence on community dynamics. Quadrats in severely disturbed areas, which were characterized by multiple treefalls and extensive canopy loss, had higher levels of diversity and variation in community assemblage than quadrats in areas characterized primarily by branch loss and defoliation. A rapid divergence in community composition between quadrats in the most- and least-severely disturbed areas resulted in the development of statistically distinct community states across relatively small scales. This provides further evidence that severe cyclones are important in maintaining species diversity in tropical forests.

The 2010/2011 Natural Disasters and Queensland's Cultural Heritage

The Australian continent, particularly the state of Queensland, was subjected to widespread and unprecedented rainfall from the end of November 2010 through to January 2011. Many parts of southern and central Queensland received well above average rainfall over this period causing extensive riverine flooding. Several flash flood events resulted in significant infrastructure damage and loss of human life. Three-quarters of Queensland was affected by some form of major flooding and declared a disaster zone. To compound issues, Severe Tropical Cyclone Yasi crossed the north Queensland coast in early February bringing with it widespread heavy rain, flash flooding, severe wind gusts of up to 285 km/hr and storm surges.

Forecasting Long-Lead Rainfall Probability with Application to Australia’s Northeastern Coast

Abstract The authors develop a method for the long-lead forecasting of El Niño–influenced rainfall probability and illustrate it using the economically important prediction, from the beginning of the year, of September–November (SON) rainfall in the coastal sugarcane producing region of Australia’s northeastern coast. The method is based on two probability distributions. One is the Gaussian error distribution of the long-lead prediction of the El Niño index Niño-3.4 by the Clarke and Van Gorder forecast method. The other is the relationship of the rainfall distribution to the Niño-3.4 index. The rainfall distribution can be approximated by a gamma distribution whose two parameters depend on Niño-3.4. To predict the rainfall at, say, the Tully Sugar, Ltd., mill on the north Queensland coast in SON 2009, the June–August (JJA) value of Niño-3.4 is predicted and then 1000 possible “observed” JJA Niño-3.4 values calculated from the error distribution. Each one of these observed Niño-3.4 values is then used, with the Niño-3.4-dependent gamma distribution for that location, to calculate 1000 possible SON rainfall totals. The result is one million possible SON rainfalls. A histogram of these rainfalls is the required probability distribution for the rainfall at that location predicted from the beginning of the year. Cross-validated predictions suggest that the method is successful.

DEVELOPING SUSTAINABLE BANANA PRODUCTION SYSTEMS: A CASE STUDY FROM TROPICAL AUSTRALIA

The north Queensland banana industry is under pressure from government and community expectations to exhibit good environmental stewardship. The industry is situated on the high-rainfall north Queensland coast adjacent to 2 natural icons, the Great Barrier Reef to the east and World Heritage-listed rain forest areas to the west. The main environmental concern is agricultural industry pollutants harming the Great Barrier Reef. In addition to environmental issues the banana industry also suffers financial pressure from declining margins and production loss from tropical cyclones. As part of a broader government strategy to reduce land-based pollutants affecting the Great Barrier Reef, the formation of a pilot banana producers group to address these environmental and economic pressures was facilitated. Using an integrated farming systems approach, we worked collaboratively with these producers to conduct an environmental risk assessment of their businesses and then to develop best management practices (BMP) to address environmental concerns. We also sought input from technical experts to provide increased rigour for the environmental risk assessment and BMP development. The producers' commercial experience ensured new ideas for improved sustainable practices were constantly assessed through their profit-driven 'filter' thus ensuring economic sustainability was also considered. Relying heavily on the producers' knowledge and experience meant the agreed sustainable practices were practical, relevant and financially feasible for the average-sized banana business in the region. Expert input and review also ensured that practices were technically sound. The pilot group producers then implemented and adapted selected key practices on their farms. High priority practices addressed by the producers group included optimizing nitrogen fertilizer management to reduce runoff water nitrification, developing practical ground cover management to reduce soil erosion and improving integrated pest management systems to reduce pesticide use. To facilitate wider banana industry understanding and adoption of the BMP's developed by the pilot group, we conducted field days at the farms of the pilot group members. Information generated by the pilot group has had wider application to Australian horticulture and the process has been subsequently used with the north Queensland sugar industry. Our experiences have shown that integrated farming systems methodologies are useful in addressing complex issues like environmental and economic sustainability. We have also found that individual horticulture businesses need on-going technical support for change to more sustainable practices. One-off interventions have little impact, as farm improvement is usually an on-going incremental process. A key lesson from this project has been the need to develop practical, farm scale economic tools to clarify and demonstrate the financial impact of alternative management practices. Demonstrating continued profitability is critical to encourage widespread industry adoption of environmentally sustainable practices

Plant functional traits explain interspecific differences in immediate cyclone damage to trees of an endangered rainforest community in north Queensland

Abstract Cyclones cause profound immediate impacts on tropical rainforest trees, including defoliation, limb loss, snapping of stems and uprooting. Some studies have shown that plant functional traits such as tree size, buttress roots and wood density are correlated with these forms of cyclone damage. On 20 March 2006, Severe Tropical Cyclone Larry crossed the north Queensland coast and proceeded inland across the Atherton Tablelands, impacting the critically endangered Mabi Type 5b rainforest. We investigated the effects of Cyclone Larry on common tree species by categorizing damage to trees as uprooted, snapped, limbs damaged (light, moderate, severe) or upright and estimating levels of defoliation. Damage was then related to functional traits including tree size, presence of buttress roots, wood density, and leaf size and strength. Levels of damage differed between species. Tree size (diameter at breast height) and the presence of buttress roots were not related to damage levels. Wood density was significantly negatively correlated to proportion of trees with snapped stems and significantly positively correlated with the proportion of trees upright with no or light limb damage. Levels of defoliation were significantly related to leaf strength (specific leaf area – SLA) and to leaf width, but not other components of leaf size (area or length) or petiole length. Species with high wood density and low SLA (e.g. Argyrodendron spp.) were found to have high cyclone resistance, the ability to resist damage, while species with low wood density and high SLA (e.g. Dendrocnide photinophylla) exhibited low resistance. However, traits related to low resistance are also those linked to rapid growth and high cyclone resilience, the ability to recover from damage, so it is unlikely that the Mabi forest will experience long‐term changes in floristic composition following Cyclone Larry.

Recruitment dynamics of invasive species in rainforest habitats following Cyclone Larry

Abstract In tropical forests, natural disturbance creates opportunities for species to claim previously utilized space and resources and is considered an important mechanism in the maintenance of species diversity. However, ecologists have long recognized that disturbance also promotes exotic plant invasions. Cyclones cause extensive defoliation, loss of major branches and multiple tree falls, resulting in a significantly more open canopy and increased light and heat levels in the understorey. The widespread and massive disturbance caused by cyclones provides ideal conditions for rapid recruitment and spread of invasive species. The ecological roles of invasive species in rainforest habitats following such a severe disturbance are poorly understood. Severe category 4 Cyclone Larry crossed the North Queensland coast in March 2006 causing massive disturbance to rainforest habitats from Tully to Cairns and west to the Atherton Tablelands. We established 10 plots in an area extensively damaged by this cyclone near El Arish in North Queensland. On each plot nine 2 × 2 m quadrats were established with three quadrats per plot in each of the following treatments: (i) complete debris removal down to the soil layer, (ii) removal of coarse woody debris only, and (iii) uncleared. We monitored recruitment, growth and mortality of all native and invasive species in the 90 quadrats every 3 months since the cyclone. Here we present the recruitment dynamics of invasive species across the study area in relation to the level of disturbance, the type of quadrat treatment, and the diversity and abundance of the native recruiting flora over the first 12 months post‐cyclone. Our results suggest that invasive species will mostly comprise a transient component of the flora in the early stages of the successional response. However, some species may have longer‐term effects on the successional trajectory of the rainforest and future forest composition and structure.

The use of transplanted cultured tropical oysters ( Saccostrea commercialis) to monitor Cd levels in North Queensland coastal waters (Australia)

Bivalves are commonly used to detect metal pollution in the marine environment. Commercially cultured Milky oysters ( Saccostrea commercialis) were transplanted in various sites along the North Queensland coast and analyzed for two metals of potentially anthropogenic origin (Cd, Zn). To provide additional information, naturally occurring Black Lip oysters ( Saccostrea echinata) were also collected at the transplantation sites. The study demonstrated that the oysters species transplanted are good bioindicators of these metal concentrations in tropical waters, sensitive to variations in the environment at concentrations which are much smaller than pollution signals commonly reported for temperate waters. Three transplant experiments were carried out from May 1999 to February 2000. Milky oysters transplanted to offshore areas (Orpheus Is., Kelso Reef) accumulated Cd in the soft parts whereas oysters sampled from cages placed in Ross Creek and the Herbert River estuaries showed a decrease in Cd concentration, which resulted from an increase in dry weight. Dry weight appeared to be an important covariant affecting Cd concentration in the oysters whereas it does not unambiguously affect Zn concentrations. For the duration of the experiments, oysters sampled from the Magnetic Is. reference site showed effectively constant Cd concentrations and total Cd contents which indicates that any seasonal cycle affecting metal concentration is weak. It was found that Cd accumulation in oysters increased as ambient dissolved Cd concentration decreased, from which it was concluded that for these oysters, the predominant source of Cd was from the particulate phase rather than the dissolved phase.

Hormones and Cancer 2000

The Hormones and Cancer 2000 Meeting was held in the spectacular setting of Port Douglas on the North Queensland Coast, Australia, 3-8 November. The meeting comprised three plenary lectures and 11 sessions, two of which were conjoint with the International Aromatase Meeting being held at the same time. In addition to the oral presentations, 50 posters were presented over two lunchtime sessions. There were about 80 registrants for a meeting that was possibly one of the most laid back that I have ever attended, and where even the speakers wore the uniform of shorts, T-shirts, thongs and umbrella required by the rainy season of tropical North Queensland. Despite the relaxed atmosphere, or possibly because of it, the presentations and following discussions were of an extremely high standard. This was also the only meeting that I have ever attended that had a session devoted to a horse race! Yes, we joined the rest of Australia in watching the Melbourne Cup, which, for those who are interested, was won by Brew with novice jockey Kerrin McEvoy on board. Returning to the science, the meeting focused on recent advances in breast and prostate cancer, with particular emphasis on the role of steroids and steroid receptors in the progression, treatment and prevention of tumours. The speakers and their audience consequently encompassed all disciplines, both scientific and clinical.

Controls upon inner‐shelf sedimentation, Cape York Peninsula, in the region of 12°S

The far north Queensland coast is characterised by a juxtaposition of coral reefs and terrigenous sediment bodies. Consequently, the distribution and long‐term fate of coastal coral reefs is largely controlled by the processes responsible for sediment dispersal and accumulation. The marine environments which bound the northern Cape York Peninsula receive relatively little modern terrigenous sediment. Estimates of total riverine sediment reaching the coast north of latitude 12°S are 1 Mt y‐1 for the Great Barrier Reef coast and 2.4 Mt y‐2 for the Gulf of Carpentaria coast, corresponding to sediment fluxes (on the shore‐attached wedges) of 2000 g m2y‐1 and 800 g m2y‐1 respectively, and net rates of vertical sediment accumulation of terrigenous material of 0.4 mm y‐1 and 1 mm y‐1. The dispersal of terrigenous sediment appears to be controlled largely by coastline orientation with respect to onshore winds. On the Great Barrier Reef coast, sediment is transported northwards within a well‐defined inner‐shelf zone of terrigenous sediment, and more than half of this sediment is partitioned into the subaerial wedge. No mechanisms are identified for substantial seaward export of sediment seawards off the coastal sediment wedge and into the Great Barrier Reef lagoon. In contrast, on the Gulf of Carpentaria coast, terrigenous sediment is exported seaward and distributed over a shore‐attached wedge tens of kilometres wide. This export is probably caused by near‐bed return flows generated by winds with near‐normal incidence to the coast. Low sediment supply thus plays a role in determining the sedimentation patterns and rates in the ocean off Cape York, but appears subordinate to coastal aspect with respect to onshore winds. For the Great Barrier Reef coast in this area, in common with the central Great Barrier Reef, the possibility is reinforced that cyclones are an important control on the timing and volume of terrigenous sediment delivery to the coast, yet play a relatively minor role in the long‐term redistribution and deposition of this material.

A Numerical Study of Storm Surges and Tides, with Application to the North Queensland Coast

Abstract A two-dimensional numerical model of the shallow-water equations, with a modified Orlanski-type radiation boundary condition, is applied to study storm surges and tides on the North Queensland coast. The numerical simulations show that with the tides included in the storm surge model the sea level elevation is generally lower than if we simply add the astronomical tides to the surge. This has been previously observed and has been commonly explained as a nonlinear interaction between the storm surge and the tides. The authors demonstrate that this effect is due to the quadratic bottom friction law. Analysis of the important dynamical processes yields a simple rule to estimate the total sea level due to the combined effects of a storm surge and tide.

The toad that ate Australia

In 1935, to combat an infestation of sugar cane beetles, well intentioned growers along Australia's North Queensland coast introduced a variety of Central American toad (Bufo marinus) to their canefields. The reality, however, has been different. The beetles, unfortunately, live high in the cane stalks, beyond the reach of the ground dwelling toad, which promptly set off on a 60-year march across Australia. Today, both beetle and toad are doing nicely; a one billion strong cane toad army now holds sway over 500,000 square kilometers north, west, and south of the original North Queensland beachhead. To check that advance, Australia's government is considering releasing a biological agent-a species-specific virus-that will selectively kill the invader. Firstly, however, the possible impacts of these toads must analysed in detail-the method used involves machine learning. By monitoring the population fluctuations of frog species living at the vanguard of the cane toad advance, the speed of the encroachment can be measured, as well as the damage the cane toad causes. The undertaking involves training a computer software program to automatically identify the calls that various species of frog make, monitoring the types and numbers of frogs found at several locations over successive wet seasons when the frogs are active, and marking any population declines as the wave of cane toads passes through.

Hydrology of Lake Eyre, Australia: El Niño link

All major ephemeral rivers of Australia lie in the Lake Eyre basin. Dry for years, on occasions they carry enormous floods, with annual volumes of 40 km 3 and instantaneous discharges of the order of 30,000 m 3 s −1. Mean annual runoff of the basin is 4 km 3 or 3.5 mm, significantly less than the 57 mm for the whole of Australia. This paper examines Lake Eyre and its drainage basin, describing the historical hydrology of the catchment, both in terms of instrument records and inflows hindcast using a model based on the technique of coral fluorescence palaeohydrological reconstruction. Coral fluorescence is a function of nearby-river discharge, and can be used to reconstruct annual river outputs reconstruction. Coral fluorescence is a function of nearby-river discharge, and can be used to reconstruct annual river outputs beyond the instrument period. The Burdekin River catchment runoff history is strongly paralleled by the volumes of Lake Eyre inflows during the period of common reliable instrument gaugings. The Burdekin runoff data have been extended back to 1735 A.D. using the correlation between river discharge and annual growth-band fluorescence in an old coral from Pandora Reef, off the North Queensland coast. For the instrument period 1952 to 1980, 73% of the variance between coral fluorescence and Burdekin discharge is common. During the period 1949–1980, 41% of the variance between coral fluorescence and Lake Eyre inflow data is common. Modelled inflows to Lake Eyre for the period 1885–1948 are based on the latter data set.

Late Pleistocene and Holocene sea-level change in the Australian region and mantle rheology

SUMMARY Spatial and temporal variations in sea-level are produced by the melting of the Late Pleistocene ice and by the Earth's response to the redistribution in surface loads. By examining different parts of the sea-level curves of the past 20 000 yr from geographically widely distributed regions it becomes possible to constrain models of the melting history of the ice sheets and of the Earth's rheology. Observations from sites away from the former Arctic ice sheets, such as the Australian and South Pacific region, are particularly important for constraining the total meltwater volumes added into the oceans in the past 20 000 yr and the rates at which this occurred. These observations indicate that the Antarctic ice sheets provided a significant contribution to the sea-level rise at a rate that was approximately synchronous with the melting of the Laurentide ice sheet, except for the interval 9000–6000 yr ago when it may have lagged behind. Minor melting of the Antarctic ice sheet appears to have continued throughout the Late Holocene. Differential observations of the Late Holocene sea-level change recorded at sites in the same region are particularly useful for estimating parameters describing the Earth's non-elastic response to surface loading. The effective parameters used here are a lithospheric thickness, an upper mantle viscosity, and a lower mantle viscosity describing the response below 670 km depth. With the observations used here, it is not possible to separate the lithospheric thickness H from the upper mantle viscosity and the viscosity results are based on the assumption that 50 ≤H≤ 100 km. Neither do these observations provide a resolution of the depth dependence of viscosity in the upper mantle and the resulting estimates are effective parameters only. Differential sea-levels along continental margins and along the shores of large gulfs and bays constrain the effective upper mantle viscosity to be about (1–2) × 1020 Pa s−1 while differential values from islands of different sizes are suggestive of a somewhat lower value. The lower mantle (taken to be below 670 km depth) viscosity is about two orders of magnitude greater than this. The estimated ice and rheological models explain many of the Holocene sea-level observations throughout the Australian and southern Pacific region. The tilting of continental margins, as exemplified by observations of variable amplitudes of the Holocene high-stands and the variable times at which sea-levels first reached their present level along the north Queensland coast and Great Barrier Reef, is well represented by these models. Differential Holocene sea-levels observed along the narrow Spencers Gulf of South Australia are also well explained by the models and in neither case is it necessary to invoke tectonic motions. Predicted Late Holocene sea-levels at small-to medium-sized islands are characterized by small amplitude high-stands that reached their maximum values about 4000–2000 yr ago, consistent with observations from the Society, Cook and Tuamotu Islands.

Observed effects of topography on the wind field of cyclone winifred

This paper describes some of the evidence of marked topographic effects associated with a moderately severe tropical cyclone which crossed the North Queensland Coast in February 1986. These effects include funnelling, increased turbulence, anomalous wind records and increased wind speeds over hills.

Aliphatic hydrocarbons in surface sediments from the North Queensland coast and Great Barrier Reef: Effects of tropical cyclone Winifred

Aliphatic hydrocarbons were determined in inner shelf and reef lagoon surface sediments off the North Queensland coast near Innisfail in February 1986, immediately after tropical cyclone Winifred passed through the region causing severe rainfall, runoff, and disturbance of bottom sediments. Lagoon sediments from Feather, Gilbey, and Potter reefs 25–50 km offshore were characterized by a suite of C 15–C 25 n-alkanes and alkenes derived predominantly from algal sources; terrestrial hydrocarbons were not present. In contrast, inner shelf sediments contained relatively large amounts of terrestrial derived C 25–C 33 n-alkanes which decreased in concentration with distance from the coast. Inner shelf sediments collected after the cyclone also contained a suite of petroleum-derived hydrocarbons. The concentrations of terrestrial-derived hydrocarbons increased in samples collected from the inner shelf after the cyclone. However, the distribution of terrestrial hydrocarbons was largely confined to the inner shelf after the cyclone, and only occurred in trace concentrations in midshelf sediments. These results indicate that cyclone-related outwelling of suspended sediments (and presumably nutrients) from rivers was confined to the inner shelf and did not reach the reef zone. The post-cyclone phytoplankton bloom was probably caused by resuspension of bottom sediments and release of porewater nutrients rather than advection of river plumes to the offshore reefs.

Dune formation on the humid tropical sector of the North Queensland Coast, Australia

AbstractSeveral previous attempts have been made to explain the apparent poor development of coastal dunes in the humid tropics in terms of lack of wind energy, failure of sand supply to the shoreline, excessive climatic wetness, salt crust formation on beaches, and the character of tropical back‐beach vegetation. However, recent published reports indicate that coastal dune occurrences are more common in the humid tropics than was formerly thought, throwing suspicion on the idea that environmental conditions militate against dune formation in these areas as a whole. Evidence from the humid tropical sector of the North Queensland coast suggests that the poor development of dunes in this area primarily reflects poor sediment sorting in the beach and nearshore zone and low wind energy at the shoreline due to the nature of the coastal orientation and physiography in relation to the prevailing southeasterly winds. These limiting factors are not unique to humid tropical climates.