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The purpose of this study was to examine mathematically able female adolescents' perceptions of their accelerated mathematics programs. To this end, eight female adolescents were asked to reflect retrospectively in response to a self-administered questionnaire on their perceptions and experiences of a secondary accelerated mathematics program and their engagement in the Victorian Certificate of Education subject, Mathematical Methods Units 3 and 4, as accelerated Year 11 students. The qualitative findings revealed that the participants valued their accelerated mathematics learning opportunities, achieved satisfaction with their accelerated learning in their study of Mathematical Methods Units 3 and 4 and academic results, and appreciated the additional study choices in Year 12 that resulted from their accelerated learning. Statistical evidence obtained from the Victorian Curriculum and Assessment Authority (VCAA) that compared the results of Year 11 and 12 students studying Mathematical Methods Units 3 and 4 over two academic years found that the cohort of accelerated Year 11 students generated a higher mean score than their Year 12 counterparts. The findings of the study provide support for the educational practice of accelerating mathematical learning for highly mathematically able adolescents.

Mycobacterium ulcerans (MU) is known to be endemic in heavily touristed coastal regions of Victoria and is the cause of Buruli ulcer (BU) disease. The incidence, severity and geographic spread of MU infection/BU disease is increasing, including metropolitan Victorian suburbs. While the specifics of disease transmission and effective prevention strategies remain uncertain, severe complications can be mitigated by health systems that provide vigilant population surveillance to underpin early recognition, early specialist involvement and definitive treatment for the individual. Current theories regarding disease transmission and 'best practice' (or best guess) prevention and mitigation measures are presented herein. Opportunities to improve the health system response to this emerging public health threat are identified. It is incumbent upon all healthcare providers, including ED clinicians, to contribute by familiarising themselves with the established and emerging areas of endemicity of MU infection and the array of BU clinical presentations. [ABSTRACT FROM AUTHOR]

In this article, we consider the complex and dynamic inter-relationships between individual science teachers, the social space of their work and their dispositions towards teacher leadership. Research into the representation of school science departments through individual science teachers is scarce. We explore the representations of four individual teachers to the assertions of teacher leadership proposed by Silva et al. (Teach Coll Rec, 102(4):779-804, 2000). These representations, expressed during regular science department meetings, occur in the social space of Bourdieu's "field" and are a reflection of the "game" of science education being played within the department. This departmentally centred space suggests an important implication when considering the relationship between subject departments and their schools. The development of an individual's representation of teacher leadership and the wider "field" of science education appears to shape the individual towards promoting their own sense of identity as a teacher of science, rather than as a teacher within a school. Our work suggests that for these individuals, the important "game" is science education, not school improvement. Consequently, the subject department may be a missing link between efforts to improve schools and current organizational practices.

Aim: The risk of dying from COVID‐19 is higher for those who are older, immune‐compromised, or chronically ill. Vaccines are an effective strategy in reducing mortality and morbidity from COVID‐19. However, for COVID‐19 vaccination programs to reach full potential, vaccines must be taken up by those at greatest risk, such as cancer patients. Understanding the perspectives of all stakeholders involved in cancer patient COVID‐19 vaccine uptake will be critical to ensuring appropriate support, and information is provided to facilitate vaccination. The aim of this research was to explore the longitudinal views of cancer stakeholders regarding COVID‐19 vaccination. Methods: Semistructured interviews were conducted with cancer patients (n = 23), family members (n = 10), cancer health professionals (n = 19), and representatives of cancer nongovernment organizations (n = 7) across Australia 6 and 12 months postrecruitment. Transcripts were thematically analyzed, using an inductive approach. Results: All stakeholder groups expressed mostly positive attitudes toward COVID‐19 vaccination, with the following key themes identified: (1) high motivation—vaccination perceived as offering health protection and hope; (2) hesitancy—concern about vaccine hesitancy among the general population, with a minority hesitant themselves; (3) confusion and frustration—regarding the vaccine rollout and patient eligibility; (4) uncertainty—about vaccination in the context of cancer; (5) access to vaccination; and (6) desire for expert individualized advice—on vaccine interaction with cancer treatments. Conclusion: These findings highlight the COVID‐19 vaccine concerns and information needs of cancer stakeholders. Policymakers need to provide clear tailored information regarding vaccine eligibility, accessibility, benefits, and risks to facilitate vaccine uptake. [ABSTRACT FROM AUTHOR]

Gully rehabilitation can contribute to catchment management by stabilizing erosion and reducing downstream sediment yields, yet the globally observed responses are variable. Developing the technical basis for gully rehabilitation and establishing guidelines for application requires studies that evaluate individual rehabilitation measures in specific environments. An eight‐year field experiment was undertaken to evaluate sediment yield and vegetation responses to several gully rehabilitation measures. The rehabilitation measures aimed to reduce surface runoff into gully head cuts, trap sediment on gully floors and increase vegetation cover on gully walls and floors. The study occurred in a savanna rangeland in northeast Australia. Two gullies were subject to treatments while four gullies were monitored as untreated controls. A runoff diversion structure reduced headcut erosion from 4.3 to 1.2 m2 yr−1. Small porous check dams and cattle exclusion reduced gully total sediment yields by more than 80%, equivalent to a reduction of 0.3 to 2.4 t ha−1 yr−1, but only at catchment areas less than 10 ha. Fine sediment yields (silt and clay) were reduced by 7 and 19% from the two treated gullies, respectively. The porous check dam deposits contained a lower percentage of the fine fraction than the parent soil. Significant regeneration of gully floor vegetation occurred, associated with trapping of organic litter and fine sediment. Increases in vegetation cover and biomass were comprised of native perennial grasses, trees and shrubs. In variable climates, long‐term gully rehabilitation will progress during wetter periods, and regress during droughts. Understanding linkages between rehabilitation measures, their hydrologic, hydraulic and vegetation effects and gully sediment yields is important to defining the conditions for their success. [ABSTRACT FROM AUTHOR]

Vision impairment can have a significant impact on the wellbeing and quality of life of an individual. Vision rehabilitation has the potential to improve these areas; however, four in five patients with vision impairment are not being referred to the appropriate services. Barriers to on-referral include, but are not limited to: (1) misunderstandings by both practitioners and patients alike regarding which individuals with vision impairment might benefit or qualify for low vision services; (2) lack of awareness of available services; (3) unfamiliarity with practice guidelines; (4) miscommunication between practitioners and patients; (5) required patient travel or limitations in access; and (6) the perceived costs of goods and services. Further, current referral patterns do not represent a holistic patient-centric approach. Vision-related quality of life questionnaires are tools which can assist health professionals in providing optimal individualised care. This review explores current evidence regarding low vision service delivery within Australia and globally, the impact of vision impairment on activities of daily living, the instruments used for the assessment of vision-related quality of life (VRQOL), competing priorities of individual needs in low vision services and rehabilitation, and provides recommendations for a more patient-centred model of care. [ABSTRACT FROM AUTHOR]

Appropriate interventions for assisting transnational social workers (TSWs), nurses and teachers in their transition into the receiving country are significant for enabling competent and safe professional practice. These professionals form a significant part of the professional workforce of many countries as globalisation and liberal migration policies encourage many to cross borders for professional practice. Engaging in employment overseas, however, is a challenging process for them as it entails relocating to a new country and working in unfamiliar sociocultural and practice contexts. While some form of profession-wide assistance is found in nursing and teaching, social workers rarely receive any such interventions. This article discusses existing support offered to transnational nurses and teachers in English-speaking countries such as the UK, US, New Zealand, Australia and Canada and suggests how a similar approach to social workers can assist their transitioning into the receiving country. It draws on the findings of a thematic review of the literature addressing support for transnational nurses, teachers and social workers. The imperative of interventions to assist transition of TSWs into host countries is explored and the article concludes with recommendations for some intervention strategies and mechanisms. [ABSTRACT FROM AUTHOR]

Background: The interest and activity in measuring and reporting the impact of publicly funded health and medical research has grown rapidly in recent years. Research evaluation typically relies on researchers for much of the information for an impact assessment. However, the acceptability and feasibility of this activity among health researchers is unknown. The aim of this study was to understand the role and opinions of cancer researchers in the growing area of impact evaluation activity, to inform the logistics of a sustainable program of impact evaluation.Methods: A brief anonymous online survey was administered to 95 current and past grant recipients funded through the external grants program at Cancer Council New South Wales. Eleven survey statements were constructed with Likert responses and supplemented with two open-ended questions. The statements covered the conceptual, attitudinal and practical aspects of impact evaluation. The survey targeted researchers from the full spectrum of cancer control research classifications. Descriptive analyses obtained response frequencies and percentages.Results: Forty-five cancer researchers completed the survey (response rate 47%) and 77% were Associate Professors or Professors. Responses were polarised for questions relating to engaging with research end-users, perceived time-pressure to collate data, and pressure to produce research outputs. Some researchers emphasised that quality was an important goal over quantity and warned that collecting impact data created incentives and disincentives for researchers.Conclusion: There was mixed support and acceptance among senior cancer researchers in Australia on their perceived role and engagement with research impact activities. Sole reliance on researchers for collating and reporting impact data may be problematic. Requesting information from researchers could be minimised and confined to final reports and possible verification of externally-led evaluations. [ABSTRACT FROM AUTHOR]

Objectives: Despite efforts to restructure mental health (MH) services across Victoria, the social and economic burden of MH illness continues to grow. This study compares MH presentations to EDs with a study undertaken 10 years earlier. Methods: The article is a retrospective observational study of MH presentations to four Victorian EDs between May and October 2013. Subjects were included if the presentation was MH related as determined by an International Classification of Diseases (version 10) discharge diagnosis, they were referred to an emergency crisis assessment team or had a documented presenting psychiatric complaint. Variables were extracted from electronic medical records and compared with 2004 data from a previous published study. Results: There were 5659 MH presentations over the 5 months compared with 2788 in 2004. The median ED length of stay decreased from 4:18 h in 2004 to 3:20h in 2013 (P< 0.001), with a significant reduction in length of stay >4h from 52.5% to 35.4% (P< 0.001). There was a 22-fold increase in short stay units as discharge destination from 0.9% to 20.2% (P< 0.001). Patients presenting with concurrent methamphetamine exposure doubled from 2.2% of presentations to 4.3% (P< 0.001). Conclusion: Despite increasing MH-related presentations, changes in ED practice have allowed improvements in delivery of care through a shortened ED length of stay and the virtual elimination of very long stays over 24 h. However, there continues to be significant variability in management and performance across hospital sites. Identifying which interventions lead to standout site performance, and subsequent application more broadly, may improve future ED delivery of care. [ABSTRACT FROM AUTHOR]

Background A regional epidemiological analysis of Australasian disasters in the 20th century to present was undertaken to examine trends in disaster epidemiology; to characterise the impacts on civil society through disaster policy, practice and legislation; and to consider future potential limitations in national disaster resilience. Methods A surveillance definition of disaster was developed conforming to the Centre for Research on the Epidemiology of Disasters (CRED) criteria (≥10 deaths, ≥100 affected, or declaration of state emergency or appeal for international assistance). The authors then applied economic and legislative inclusion criteria to identify additional disasters of national significance. Results The surveillance definition yielded 165 disasters in the period, from which 65 emerged as disasters of national significance. There were 38 natural disasters, 22 technological disasters, three offshore terrorist attacks and two domestic mass shootings. Geographic analysis revealed that states with major population centres experienced the vast majority of disasters of national significance. Timeline analysis revealed an increasing incidence of disasters since the 1980s, which peaked in the period 2005-2009. Recent seasonal bushfires and floods have incurred the highest death toll and economic losses in Australasian history. Reactive hazard-specific legislation emerged after all terrorist acts and after most disasters of national significance. Conclusion Timeline analysis reveals an increasing incidence in natural disasters over the past 15 years, with the most lethal and costly disasters occurring in the past 3 years. Vulnerability to disaster in Australasia appears to be increasing. Reactive legislation is a recurrent feature of Australasian disaster response that suggests legislative shortsightedness and a need for comprehensive all-hazards model legislation in the future. [ABSTRACT FROM AUTHOR]

Quantifying riverine sediment loads, and the uncertainty around these estimates, is important for monitoring the impact of land use on ecologically sensitive receiving waters such as the Great Barrier Reef lagoon. We used a Bayesian Hierarchical Modelling approach that assimilates information from a process model for runoff, a mechanistically motivated statistical model for sediment generation and observed runoff and sediment load data. The approach was trialled on a 10-year dataset collected from a 14-km 2 sub-catchment in the Burdekin basin, Australia. Using our model, we were able to estimate daily sediment concentrations, discharges and loads (with credible intervals) over a 10-year period, including 3 years where there were long periods of missing observational data. We found that for the high-frequency monitoring undertaken at the study site, credible intervals around sediment loads were narrow. Credible intervals were substantially wider in years where observational data were not available and load estimates relied on the underlying processes and neighbouring observations. The method presented here is the first attempt at assimilating discharge and concentration measurements with process models for the purpose of sediment load estimation. The potential for quantifying loads entering the Great Barrier Reef lagoon is promising, particularly for ephemeral streams that are typical of arid and semi-arid Australia. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Land use (and land management) change is seen as the primary factor responsible for changes in sediment and nutrient delivery to water bodies. Understanding how sediment and nutrient (or constituent) concentrations vary with land use is critical to understanding the current and future impact of land use change on aquatic ecosystems. Access to appropriate land-use based water quality data is also important for calculating reliable load estimates using water quality models. This study collated published and unpublished runoff, constituent concentration and load data for Australian catchments. Water quality data for total suspended sediments (TSS), total nitrogen (TN) and total phosphorus (TP) were collated from runoff events with a focus on catchment areas that have a single or majority of the contributing area under one land use. Where possible, information on the dissolved forms of nutrients were also collated. For each data point, information was included on the site location, land use type and condition, contributing catchment area, runoff, laboratory analyses, the number of samples collected over the hydrograph and the mean constituent concentration calculation method. A total of ∼750 entries were recorded from 514 different geographical sites covering 13 different land uses. We found that the nutrient concentrations collected using “grab” sampling (without a well defined hydrograph) were lower than for sites with gauged auto-samplers although this data set was small and no statistical analysis could be undertaken. There was no statistically significant difference (p <0.05) between data collected at plot and catchment scales for the same land use. This is most likely due to differences in land condition over-shadowing the effects of spatial scale. There was, however, a significant difference in the concentration value for constituent samples collected from sites where >90% of the catchment was represented by a single land use, compared to sites with <90% of the upstream area represented by a single land use. This highlights the need for more single land use water quality data, preferably over a range of spatial scales. Overall, the land uses with the highest median TSS concentrations were mining (∼50,000mg/l), horticulture (∼3000mg/l), dryland cropping (∼2000mg/l), cotton (∼600mg/l) and grazing on native pastures (∼300mg/l). The highest median TN concentrations are from horticulture (∼32,000μg/l), cotton (∼6500μg/l), bananas (∼2700μg/l), grazing on modified pastures (∼2200μg/l) and sugar (∼1700μg/l). For TP it is forestry (∼5800μg/l), horticulture (∼1500μg/l), bananas (∼1400μg/l), dryland cropping (∼900mg/l) and grazing on modified pastures (∼400μg/l). For the dissolved nutrient fractions, the sugarcane land use had the highest concentrations of dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON) and dissolved organic phosphorus (DOP). Urban land use had the highest concentrations of dissolved inorganic phosphorus (DIP). This study provides modellers and catchment managers with an increased understanding of the processes involved in estimating constituent concentrations, the data available for use in modelling projects, and the conditions under which they should be applied. Areas requiring more data are also discussed. [Copyright &y& Elsevier]

The article presents the results of a three year field study which examines the bank erosion and channel change on the Daintree River in Australia. It provides information on the three different methods which are employed in the study including the erosion pins, bench-marked cross-sections, and the historical aerial photos. The first method is used to asses the influence of riparian vegetation on bank erosion while the second method is used to evaluate annual changes in channel width. Moreover, the third method is used to place the short term data into a longer temporal perspective of channel change.

This paper highlights the relevant issues influencing the amount and arrangement of ground cover in savanna rangelands in Australia, and presents field measurements from hillslope scale flumes, which demonstrate how runoff and sediment loss vary with spatial patterns in ground cover. Hillslopes with relatively high mean cover, but with small patches bare of vegetation, are shown to have between 6 and 9 times more runoff, and up to 60 times more sediment loss than similar hillslopes that do not contain bare patches. The majority of sediment lost from the hillslopes is composed of fine (suspended) rather than coarse (bedload) material, although the absolute sediment loads are comparatively low. These low loads are considered to be the result of lower than average rainfall during the measurement period (2002-2005) and the high and prolonged rates of historical hillslope erosion that have exhausted the erodible material from the A-horizon. The collected data also demonstrate that a large proportion of soil is lost during the initial ‘flushing’ period of runoff events. The results presented have important implications for the management of savanna grazing systems by highlighting (i) the significance of bare patches in contributing to runoff and soil loss from hillslopes; (ii) the importance of having medium to high cover patches at the bottom of hillslopes for trapping and storing sediment and therefore reducing its entry into the stream network; and (iii) how maintenance of ground cover during the dry season reduces sediment concentrations in runoff occurring early in the wet season. [ABSTRACT FROM AUTHOR]

Focuses on a study which assessed the impact of structural changes in fiscal policy on macroeconomic stability in Australia and other developed economies since the mid-1970s. Issues in the analysis of counter-cyclical policy; Definition of counter-cyclical fiscal policy; Empirical evidence on the counter-cyclical effect of fiscal policy; Fiscal activism in Australia.

Objective: Comprehensive tumor genomic profiling (CTGP) is increasingly used to personalize treatments, providing hope, but potentially disappointment, for patients. We explored psychological outcomes in patients with advanced, incurable cancer, after receiving CTGP results.Methods: Participants with advanced, incurable cancer (n = 560, mean age 56, 43% university educated) in this longitudinal substudy of the Molecular Screening and Therapeutics Program (MoST), completed questionnaires before and after receiving CGP results. MoST participants, recruited from Australian oncology clinics, undergo CTGP, and if there are actionable findings, are offered treatment in a related therapeutic trial if available.Results: Patients who received actionable results, (n = 356, 64%) had lower gene-related distress (MICRA) (p < 0.001) and Impact of Events scores (p = 0.039) than patients with non-actionable results. Those with actionable results offered ensured access to tailored treatment (n = 151) reported lower anxiety (p = 0.002) and depressive symptoms (p = 0.01) and greater hope (p = 0.002) than those not offered. Positive attitudes towards uncertainty and higher self-efficacy for coping with results were associated with lower psychological distress and uncertainty, and higher hope and satisfaction with the decision to have CTGP (ps=0.001-0.047). Those with higher knowledge reported greater anxiety (p = 0.034).Conclusion: Receiving a non-actionable CTGP result, or an actionable result without ensured access to treatment, may cause increased distress in advanced cancer patients. Coping style was also associated with distress.Practice Implications: Pre-testing assessment and counseling addressing attitudes toward uncertainty and self-efficacy, and post-CTGP result support for patients receiving a non-actionable result or who receive an actionable results without ensured access to treatment, may benefit patients. [ABSTRACT FROM AUTHOR]

Abstract: Identifying how agricultural practices can be changed to reduce sediment loss requires knowledge of the erosion processes and spatial areas contributing to end of catchment sediment loads. The Burdekin River basin in northeast Australia is a priority for such knowledge because of its large size (130,000km2), ongoing public investment in changing agricultural practices, and because sediment exports are known to affect the health of a significant aquatic ecosystem, the Great Barrier Reef (GBR). This study applied sediment tracing techniques within the Burdekin River basin to identify the contributions of surface versus subsurface soil, and spatial areas to fine sediment export. Tracer properties included fallout radionuclides and geochemistry. The contributions of each sediment source to river sediment were identified with 95% confidence intervals using a Monte-Carlo numerical mixing model. Between 77% and 89% of fine sediment loss in the study area was derived from subsurface soil sources. High-resolution monitoring of river suspended sediment concentrations indicated that sediment sources were in close proximity to the drainage network, since concentrations were higher on the rising limb than the falling limb of large hydrographs. Gully erosion is likely to be the dominant subsurface soil erosion process, although channel bank erosion and hillslope rilling cannot be discounted. The results contrast with previous sediment budget spatial modelling, which predicted that hillslope erosion was the dominant sediment source in the area, thus demonstrating the need to independently verify modelling predictions where input datasets are poor. The contribution of surface soil to river sediment was generally similar between catchments which were currently grazed and two catchments where livestock grazing ceased 7 years ago. Concurrent increases in vegetation cover in the non-grazed catchments indicate that surface erosion rates had declined, suggesting that subsurface soil erosion rates had also declined by a similar amount. The estimated contributions of spatial source areas within the large study catchments had narrower confidence intervals when source areas were defined using sediment from geologically distinct river tributaries, rather than using soil sampled from geological units in the catchment, since tributary sediment had less-variable geochemistry than catchment soil. Programs to reduce fine sediment losses from the Burdekin River basin should primarily focus on reducing sub-surface soil erosion proximal to the basin's drainage network. Understanding the biophysical processes of pollutant generation is important to help guide on-ground activities to improve water quality. [Copyright &y& Elsevier]

• We investigated the ability of genetically divergent Haemonchus contortus strains to interbreed. • Overlapping inter-strain morphological and morphometric variation was observed. • Co-infecting strains interbreed, but proportions of F 1 progeny depart from Mendelian expectations. • Post-zygotic incompatibility in hybrid progeny of paternal parents is consistent with incipient speciation of MHco10(CAVR). • Our results have implications for ecology of anthelmintic resistant parasite populations. Haemonchus contortus , in common with many nematode species, has extremely high levels of genetic variation within and between field populations derived from distant geographical locations. MHco10(CAVR), MHco3(ISE) and MHco4(WRS) are genetically divergent H. contortus strains, originally derived from Australia, Kenya and South Africa, respectively, that have been maintained by numerous rounds of in vivo experimental infection of sheep. In order to explore potential pre-zygotic competition or post-zygotic incompatibility between the strains, we have investigated the ability of MHco10(CAVR) to interbreed with either MHco3(ISE) or MHco4(WRS) during dual strain co-infections. Sheep were experimentally co-infected with 4000 infective larvae (L 3) per os of the MHco10(CAVR) strain and an equal number of either the MHco3(ISE) or the MHco4(WRS) strain L 3. The adult worm establishement rates and the proportions of F 1 progeny resulting from intra- and inter-strain mating events were determined by admixture analysis of microsatellite multi-locus genotypes. Although there was no difference in adult worm establishment rates, the proportions of F 1 progeny of both the MHco10(CAVR) × MHco3(ISE) and MHco10(CAVR) × MHco4(WRS) dual strain co-infections departed from Mendelian expectations. The proportions of inter-strain hybrid F 1 progeny were lower than the expected 50%, suggesting either pre-zygotic competition or post-zygotic incompatibility between the co-infecting strains. To investigate this further, both eggs and hatched L 1 of broods from single adult female worms recovered from each dual co-infection were genotyped. Unhatched eggs from the broods revealed no inter-strain hybrid genotype deficit, suggesting there is no pre-zygotic competition between the strains. In contrast, there was a deficit in L 1 inter-strain hybrid genotypes in the broods derived from MHco3(ISE) or MHco4(WRS) maternal parents, but not from MHco10(CAVR) maternal parents. This suggests that hybrid progeny of MHco10(CAVR) paternal parents have reduced post-zygotic development and/or viability consistent with incipient speciation of the MHco10(CAVR) strain. The presence of mating barriers between allopatric H. contortus strains has important implications for parasite ecology, including the ability of newly introduced anthelmintic-resistant parasite populations to compete and interbreed with populations already established in a region. [ABSTRACT FROM AUTHOR]

Increased erosion related to climate and/or land cover change has adverse impacts on terrestrial and aquatic ecosystems. Mapping of erosion hotspots improves our ability to identify and potentially remediate the most active erosion sources. The topical savannas of the Great Barrier Reef catchments, in northeast Australia, are generating excessive sediment yields, primarily from gully erosion. To reduce the adverse impacts on marine ecosystems, there is an urgent need to identify priority erosion hotspots and implement mitigation measures. While repeat airborne LiDAR surveys allow subtle topographic change detection, they are cost-intensive for catchment-scale applications and their applicability is constrained by data avalability and detection treshold of ground level change. In contrast, satellite-based radar imagery can allow large scale tracking of geomorphic change at high temporal resolution. Here we apply a new method based on Sentinel-1 C-band radar images and Coherence Change Detection (CCD), where large stacks of interferometric coherence images are subdivided with rain gauge time-series for separation of erosion-rich and erosion-free coherence information. After correcting the former with the latter, the resulting corrected coherence maps are compared with differential elevation models derived from multitemporal LiDAR, regional scale gully delineation maps, maps of gullying potential and in-situ field verification. Our results demonstrate the promising potential of this technique in detecting gully erosion hotspots. The coherence loss indicating erosion/deposition is well detected in wide gully morphologies, however, the line-of-sight angle does not allow penetration into narrow linear gullies. Further, CCD detects sheetwash or rill erosion occurring in areas identified as at risk of gully expansion, which is commonly below detection threshold for multitemporal LiDAR datasets. When used with LiDAR-derived geomorphic change mapping and gullying potential maps, CCD allows identification of gully erosion dynamics and forecasting gully evolution and creation, which is critical for supporting mitigation measures. • Sentinel-1 radar coherence stacks map erosion hotspots in northeast Australia. • Erosion-free coherence is used to correct erosion-affected coherence images. • Comparison with DoD, gully maps, gullying potential maps and in situ observations. • Capability is indicated to detect early development and deepening of gullies. • A cost-effective, semi-quantitative mapping of large-scale erosion patterns. [ABSTRACT FROM AUTHOR]

Following atmospheric nuclear weapons testing in the 1950s and 1960s significant quantities of 137Cs and 239+240Pu were deposited worldwide. In recent decades, 137Cs has been commonly used as a tracer of soil erosion and sedimentation, particularly in the Northern Hemisphere where atomic deposition was three times as great as in the Southern Hemisphere. The relatively short 30-year half-life of this isotope means that its sensitivity as a tracer is rapidly decreasing. In contrast, with half-lives of 24,110 and 6561 years, the sensitivity of the two plutonium isotopes remains essentially the same as when it was deposited. Here we use the technique of Accelerator Mass Spectrometry to demonstrate the potential of anthropogenic Pu as an alternative to 137Cs as a tracer of soil transport in Australia. We measure an average 137Cs/239+240Pu activity ratio of 27.3±1.5 and an average 240Pu/239Pu atom ratio of 0.149±0.003, both slightly lower than the global average. [Copyright &y& Elsevier]

We report a comprehensive inventory of 10Be-based basin-wide denudation rates (n = 160) and 26Al/10Be ratios (n = 67) from 48 drainage basins along a 3000 km stretch of the East Australian passive continental margin. We provide data from both basins draining east of the continental divide (n = 37) and discharging into the Tasman and Coral Seas, and from basins draining to the west as part of the larger Murray-Darling and Lake Eyre river systems (n = 11). 10Be-derived denudation rates in mainstem samples from east-draining basins range between 7.7 ± 1.9 (± 1σ; Mary) and 54.6 ± 13.7 mm kyr−1 (North Johnstone). Denudation rates in tributary samples range between 3.0 ± 0.7 (Burdekin) and 70.2 ± 18.9 mm kyr−1 (Liverpool). For west-draining basins, denudation rates are overall lower and with a more restricted range of 4.8 ± 1.2 (Barcoo) to 15.4 ± 3.6 mm kyr−1 (Maranoa) in mainstem samples, and between 4.4 ± 1.0 (Murrumbidgee) and 38.5 ± 7.8 mm kyr−1 (Murray) in tributary samples. East Australian denudation rates (median = 14.5 mm kyr−1) are similar to those found in other postorogenic landscapes (global median = 12.4 mm kyr−1) and the medians of the top 10% denudation rates recorded here (46.5 mm kyr−1) and in other passive margin settings are also similar, despite differences in topography and precipitation. These median denudation rate values are close to the 95th percentile denudation rate for all tectonically passive basins (≈53 mm kyr−1) and are very similar to the global silicate weathering speed limit (≈58 mm kyr−1) calculated as the 95th percentile of global soil weathering rates. The above suggests that in post-orogenic terrain, the overall rates of topographic decay have a 'speed limit' that is imposed by the rate at which rock is converted to soil by chemical weathering. Denudation rates along the East Australian margin correlate with topographic metrics at both the mainstem basin scale and at the smaller tributary basin scale suggesting that topography exerts the main control on rates of landscape lowering in this setting. An important link between denudation rate and rainfall is also inferred: the highest mainstem 10Be denudation rates all occur in basins which also have the highest rainfall amounts and there is a strong correlation between the distance knickpoints have travelled upstream from the river mouth and basin area — a proxy for discharge and so to some extent also rainfall. On both sides of the divide, in all but a few of the samples, 26Al/10Be ratios are consistently lower than what is expected in a setting where sediments experience a simple and continuous exposure history. East of the continental divide, the lowest 26Al/10Be ratios are found in basins that also experience increased flood variability. We posit that there is a causal link between the hydrological variability that characterises the coastal rivers of eastern Australia and the observed non-steady state 26Al/10Be ratios: the periodic stripping of vertically accreted floodplains by large floods means that deeper and potentially older material is periodically incorporated into the sediment mix transported by the modern river. [ABSTRACT FROM AUTHOR]

• Sediment loads are lower in a catchment with cattle excluded for 17 years. • Most of the sediment and nutrient load is derived from a few large runoff events. • Recovery of degraded savanna rangelands is slow and strongly influenced by climate. • Road work can significantly increase sediment and nutrient concentrations and loads. Excess sediment and nutrient yields from degraded rangelands have detrimental off-site ecological and on-site economic impacts, yet the effect of reduced grazing pressure on water quality is not fully understood. This study compares 15-year records of runoff, sediment and nutrient yields amongst three ephemeral headwater catchments (10.5–13.5 km2) with similar wet/dry tropical climate and landform characteristics, but contrasting cattle grazing pressure. The catchments are located within the Burdekin River basin which is the largest source of sediment and particulate nutrients to the Great Barrier Reef, Australia. Estimated mean annual total suspended sediment (TSS), total nitrogen (TN) and total phosphorus (TP) loads are: 0.6 t ha−1, 1.3 and 0.3 kg ha−1, respectively, in a catchment from which cattle were excluded over the study period ('Main Creek'); 1.5 t ha−1, 1.4 and 0.4 kg ha−1, respectively, in a catchment where grazing pressure was reduced from approximately 25 to 13 cattle per km2 at the commencement of monitoring ('Weany Creek'); and 1.4 t ha−1, 3.0 and 0.5 kg ha−1, respectively, in a catchment which maintained higher levels of grazing pressure ('Wheel Creek', approximately 25 head per km2). Higher annual sediment loads in the grazed catchments compared to the ungrazed catchment are likely due to degradation of soil water storage capacity, soil surface protection and gully erosion rates, but could also be influenced by differences in catchment geomorphic attributes (e.g., hydrological and sediment connectivity). Events with runoff >20 mm (16–25% of all events) generated 79–85% of the total runoff volume and 71–78% of the total TSS, TN, and TP loads. At the event timescale, there are not clear differences in runoff, sediment and nutrient loads among the catchments, attributed to variability in catchment conditions (e.g., antecedent soil moisture, rainfall intensity, vegetation) that occur within- and between events. It is concluded that recovery of degraded savanna rangelands following reduction in livestock grazing pressure takes decades and is strongly influenced by climate. Measuring water quality responses to land management change in variable climates requires nested spatial monitoring over long time scales that also includes factors that can influence the response (e.g., climate, soil properties, vegetation and land use). [ABSTRACT FROM AUTHOR]

Strong scientific evidence indicates increased quantities of sediment are entering the Great Barrier Reef lagoon and grazing lands are a key source. Understanding the effects of land cover changes caused by grazing management on surface hydrology is important for water resources, controlling erosion and assessing land management practices. A distributed hydrological modelling platform, wflow, (that was developed as part of Deltares's OpenStreams project) is used to assess the effect of ground cover on runoff generation processes. The model was applied to Weany Creek, a small catchment (13.6 km2) on Granodiorite soils in the Burdekin Basin, North Australia. Satellite and drone-based ground cover data, high resolution topography from LiDAR, soil properties, and distributed rainfall data were used to parameterise the model. Wflow was used to predict total runoff, peak runoff, time of rise, and lag time for several events of varying magnitudes and antecedent moisture conditions. We selected a series of hydrographs with different magnitudes from recorded runoff data (2000-2017) to calibrate the model., and another set of hydrographs were used to evaluate model performance by comparing observed and predicted stormflow hydrograph attributes using the Nash Sutcliffe efficiency metric. By using a distributed model, spatiotemporal patterns of overland flow occurrence across the catchment were also evaluated. The results show that a process-based distributed model can be calibrated to simulate spatial and temporal patterns of runoff generation processes, to help identify the relative influences of canopy interception, bare ground extent, soil surface condition and soil moisture storage on rainfall retention. This understanding of runoff generation helps to identify objectives for grazing management and to quantify links between vegetation cover and erosion rates which are influenced by runoff volumes. In particular, we conclude that increasing vegetation cover can reduce surface runoff, to significantly reduce annual gully erosion rates and gully extent in this dissected landscape. [ABSTRACT FROM AUTHOR]