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Introduction: Australia's first proton beam therapy (PBT) centre will house a fixed-beam room and two gantry rooms. As the only PBT facility in Australia for at least the short term, there is a need to efficiently allocate treatment appointments between the gantry and fixed-beam rooms. This planning study assesses the dosimetric differences between fixed-beam and gantry-based treatment plans for base of skull chordoma, one of the core indications likely to be referred for PBT in Australia. Methods: Retrospective gantry-based and fixed-beam treatment plans were generated for five patients with base of skull chordoma. Fixed-beam plans were generated with a conventional horizontal patient positioning system. Robust intensity modulated proton therapy (IMPT) optimisation and evaluation techniques were used for both delivery systems. Plans were designed to maximise target coverage while adhering to maximum dose constraints to neighbouring critical organs at risk. Results: Robust target coverage and integral dose were found to be approximately equivalent for the gantry-based and fixed-beam plans. Doses to specific organs at risk could be reduced with the gantry-based geometry; however, the gantry-based plans did not exhibit a general decrease in doses to organs at risk. Conclusion: A fixedbeam treatment plan was found to be non-inferior to a gantry-based treatment plan for all base of skull patients included in the current study. [ABSTRACT FROM AUTHOR]

Geodesign theory and practice may be informed and strengthened by studying contrasts between contemporary perspectives and historical processes. In this paper, we disaggregate contemporary geodesign into three trajectories found in the literature: (1) tightly coupled design and impact simulations, (2) a framework for landscape planning, and (3) an organic process. Augmenting these trajectories with two taxonomies of geodesign elements, we look for evidence of geodesign in a longitudinal descriptive case study. Analysis reveals a story of design and planning unfolding over a long period of time at multiple geographic scales interwoven with persistent conflict. The case revealed evidence of geodesign approaches and elements in historical planning and design. The events studied also led to high-quality outcomes that are diffusing regionally. Results of this investigation yield implications for improved geodesign practice and theory including broadening the discourse around geodesign to include time and conflict and expanding geodesign's theoretical frameworks. [ABSTRACT FROM AUTHOR]

Proton‐to‐photon comparative treatment planning is a current requirement of Australian Government funding for patients to receive proton beam therapy (PBT) overseas, and a future requirement for Medicare funding of PBT in Australia. Because of the fundamental differences in treatment plan creation and evaluation between PBT and conventional radiation therapy with x‐rays (XRT), there is the potential for a lack of consistency in the process of comparing PBT and XRT treatment plans. This may have an impact on patient eligibility assessment for PBT. The objective of these guidelines is to provide a practical reference document for centres performing proton‐to‐photon comparative planning and thereby facilitate national uniformity. [ABSTRACT FROM AUTHOR]

Understanding housing preferences is critical for successful compact city development. However, there is limited research on understanding preference heterogeneity in dwelling type choices. Using the Household Income and Labour Dynamics in Australia survey, this paper identifies the key housing and built environment characteristics associated with changes in dwelling type choice from detached houses to high-density. A latent class choice model captures the heterogeneity of dwelling type preferences within a traditionally low-density city, Brisbane, Australia. Findings reveal six household classes with distinct dwelling preferences: Class 1 (senior households without children with other family members) and Class 2 (couple families with children) in inner-city areas, Class 3 (high-income young households) and Class 4 (low-income households without children) in middle-city areas, Class 5 (low-income families with children) and Class 6 (middle-income young families without children) in outer-city areas. Residential environments with better access to educational facilities encourage Classes 3 and 6 to change to high-density living. Greater land use diversity encourages Classes 2, 3, and 6 to move towards high-density living. The findings can be used to design and improve high-density housing for targeted population groups across inner-, middle- and outer-city areas. [ABSTRACT FROM AUTHOR]

Topographic models provide a useful tool for understanding gully occurrence in the landscape but require reliable estimates of gully head drainage areas. Modern high‐resolution topography data (collected using structure from motion photogrammetry or light detection and ranging) is increasingly used for topographic studies of gullies, but little work has been done to assess the variability of gully head drainage area estimates using different methods. This study evaluated alternative approaches to using high‐resolution digital elevation models (DEMs) so that gully topographic models can be more readily applied to any area with suitably high‐resolution data. Specifically, we investigated the impact of single‐ or multiple‐direction flow routing algorithms, DEM hydrologic‐enforcement procedures and spatial resolution on gully head drainage area estimation. We tested these methods on a 40 km2 site centred on Weany Creek, a low‐relief semi‐arid landscape draining towards the Great Barrier Reef, Australia. Using a subroutine to separate gully heads into those with divergent or convergent flow patterns upslope, we found that divergent flow conditions occurred at half of 484 studied gullies. Drainage areas estimated by different flow routing algorithms were more variable in these divergent cases than for convergent cases. This variation caused a significant difference between topographic threshold parameters (slope b and intercept k) derived from single‐ or multiple‐direction flow routing algorithms, respectively. Different methods of hydrologic enforcement (filling or breaching) also affected threshold analysis, resulting in estimates of the exponent b being ~188% higher if the DEM was filled than if breached. The testing of the methods to date indicates that a finer resolution (≤2 m) DEM and a multiple‐direction flow routing algorithm achieve the most realistic drainage area estimates in low‐relief landscapes. For Weany Creek we estimated threshold parameters k = 0.033 and b = 0.189, indicating that it is highly susceptible to gully erosion. [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]

Introduction: Australia's first proton beam therapy (PBT) service, The Australian Bragg Centre for Proton Therapy and Research, is scheduled to open in the near future providing PBT for patients closer to home. Patients currently access Commonwealth funding for PBT via the Medicare Medical Treatment Overseas Program (MTOP). Proton versus photon treatment planning is a pre-requisite for the MTOP application. The Royal Adelaide Hospital (RAH) Department of Radiation Oncology has been providing this since 2016. We aim to provide a descriptive overview of our proton versus photon treatment planning process, presenting a summary of the comparative planning results and the treatment pathways selected for the patients referred.Methods: All patients referred to the RAH for comparative planning between January 2016 and December 2018 were included in the analysis. Comparative plans were generated for each case using Pinnacle or Eclipse treatment planning systems. The planning techniques used and plan quality metrics were reported.Results: Forty three patients were referred for comparative planning. The age range was 1-63 years, with the majority (72%) being paediatric patients (age ≤18 years). Of the 19 cases that have been submitted to MTOP, 16 have been accepted and 3 denied. Two of the accepted cases chose not to travel abroad for PBT. The other 14 cases have received PBT overseas.Conclusions: The RAH has provided an important service to demonstrate the dosimetric difference between PBT and photon therapy for Australian patients, an important step in supporting the funding of patients for treatment overseas. [ABSTRACT FROM AUTHOR]

• Development of a fully-automated computer algorithm for gully topographic threshold studies. • Erosion process understanding from topographic thresholds changes depending on slope estimation method. • Gully topographic thresholds vary by lithological setting. • Comparison of gully morphology with surrounding terrain revealed statistically significant relationship between gully depth and hillslope gradient. Advances in technology to acquire high-resolution topography (HRT) have enabled increasingly detailed assessments of gully erosion from digital elevation models (DEMs), but also increased the need for reliable and reproducible methods. We developed an automated algorithm for characterising morphological properties of gullies and their surrounding terrain using HRT DEMs. While this concept may seem simple, the absence of an objective and reproducible method has been a key source of error in topographic and morphological studies of gullies. The algorithm constructs a geometric model of the gully head and uses this to estimate the width, depth, and slope of the gully channel as well as slope of the surrounding terrain. This new analysis removes arbitrary decisions regarding the computation of slope for input into topographic models of gully formation and enables consistent estimation of gully head morphology. We tested the algorithm across a ∼1200 km2 area in the Fitzroy River basin of north-eastern Australia where gully erosion occurs across a range of lithologies. Results show that topographic thresholds of gully formation are more reliably estimated when slope is computed along natural flow lines upslope of gully heads, not along the sides of gullies where topography is more variable. We used the algorithm to compare gully morphological measurements, finding a statistically significant relationship between gully depth and hillslope gradient. Estimated gully topographic thresholds for our study area indicate high susceptibility to gully erosion (k ≈ 0.021), consistent with previous studies in similar semi-arid Australian landscapes. However, this estimate was larger (k ≈ 0.049) using coarser resolution (≥ 10 m) DEMs, indicating that DEM resolution affects modelled susceptibility of a landscape to gully incision. Our automated algorithm supports objective assessments of topographic studies of gullies with potential to improve comparability within and between studies. [ABSTRACT FROM AUTHOR]

Background To assess the structure of individual-level needle and syringe coverage measurement formula, and to estimate the impact of coverage-related behaviours/parameters (instances of syringe acquisition, total syringes acquired, peer-to-peer syringe distribution, injecting frequency) on overall coverage. Methods Data are drawn from the Melbourne (Australia) injecting drug user cohort study, 2010–16. Data from 518 participants were analysed. We used correlations to explore the relationships between coverage parameters; pooled multiple–linear regression to estimate the effect of each parameter on coverage over time; and exploratory factor analysis to assess the relevance of each parameter within the coverage formula. Results A 1-unit increase in injecting frequency over time reduced coverage by 10.93 percentage points, almost twice as much as other coverage parameters. Factor analysis results indicated potential improvements to coverage formula structure. Conclusions Our results suggest that reducing injecting frequency amongst people who inject drugs has the largest improvement in coverage levels, indicating harm reduction services should prioritize it. We also demonstrate that coverage measurement has been inconsistent to date. We sought to refine the method to assist in generating comparable research. [ABSTRACT FROM AUTHOR]

Research that projects biophysical changes under climate change is more advanced than research that projects socio-economic changes. There is a need in adaptation planning for informed socio-economic projections as well as analysis of how these changes may exacerbate or reduce vulnerability. Our focus in this paper is on the delivery of time-sensitive socio-economic information that can better support anticipatory adaptation planning approaches. Using a ‘multiple lines of evidence’ approach based on Australian Bureau of Statistics’ data (2010/2011), we examine the socio-economic vulnerability of the grazing sector located on Australia’s east coast. We profile the east coast grazing sector through an overview of the composition of its workforce and the value of grazing commodities produced. We then assess the potential vulnerability of the grazing sector using spatial snapshots of five factors known to shape socio-economic vulnerability in New South Wales and Queensland: (1) reliance on agriculture, (2) geographic remoteness, (3) socio-economic disadvantage, (4) economic diversity and (5) age. Our assessment of the east coast grazing sector reveals six subregions characterised by high potential socio-economic vulnerability to the impacts of climate change. We find high percentages of labour forces employed in agriculture, geographic remoteness and age (high percentages of owner/managers and employees in younger age groups) to be drivers of vulnerability. Finally, we evaluate the ways in which these vulnerabilities may be exacerbated or reduced in light of emerging environmental, economic and social trends. This approach complements demographic projection methods to deliver time-sensitive socio-economic information to support anticipatory adaptation planning. [ABSTRACT FROM AUTHOR]

Rapid reviews (RRs) are a method of evidence synthesis that can provide robust evidence to support policy decisions in a timely manner. Herein we describe the methods used to conduct RRs and present an illustrative case study to describe how RRs can be used to inform contemporary Australian health policy. The aim of the present study was to explore several important aspects ofhowRRs can inform decision makers.RRs are conducted within limited time frames of as little as 4 weeks. Policy questions may focus on issues of efficacy, service delivery and service organisation rather than reimbursement of new services, which is better answered by a more comprehensive assessment. RRs use flexible and pragmatic methods, which aim to balance the objectivity and rigour required of the reviews within limited time frames. This flexibility allows for great variation across products with regard to length, depth of analysis and methods used. As a result, RRs can be specifically tailored to address targeted policy questions and are a useful tool in the development of Australian health policy. [ABSTRACT FROM AUTHOR]

Fallout radionuclides (FRNs) 137Cs and 210Pb are well established as tracers of surface and sub-surface soil erosion contributing sediment to river systems. However, without additional information, it has not been possible to distinguish sub-surface soil erosion sources. Here, we use the FRN 7Be (half-life 53 days) in combination with 137Cs and excess 210Pb to trace the form of erosion contributing sediment in three large river catchments in eastern Australia; the Logan River (area 3700 km2), Bowen River (9400 km2) and Mitchell River (4700 km2). We show that the combination of 137Cs, excess 210Pb and 7Be can discriminate horizontally aligned sub-surface erosion sources (rilled and scalded hillslopes and the floors of incised drainage lines and gully 'badland' areas) from vertical erosion sources (channel banks and gully walls). Specifically, sub-surface sources of sediment eroded during high rainfall and high river flow events have been distinguished by the ability of rainfall-derived 7Be to label horizontal soil surfaces, but not vertical. Our results indicate that in the two northern catchments, erosion of horizontal sub-surface soil sources contributed almost as much fine river sediment as vertical channel banks, and several times the contribution of hillslope topsoils. This result improves on source discrimination provided previously and indicates that in some areas erosion of hillslope soils may contribute significantly to sediment yield, but not as topsoil loss. We find that in north-eastern Australia, scalded areas on hillslopes and incising drainage lines may be sediment sources of comparable importance to vertical channel banks. Previous studies have used the combination of 137Cs, excess 210Pb and 7Be to estimate soils losses at the hillslope scale. Here, we show that with timely and judicious sampling of soil and sediment during and immediately after high flow events 7Be measurements can augment fallout 137Cs and 210Pb to provide important erosion source information over large catchments. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The use of precision farming technology for enhanced farm management will play an essential role in future Australian livestock farming systems. Currently a gap exists between the potential perceived by precision technology developers and the on-farm benefits achieved by farmers. The concept of technological innovation systems is used in this paper to discuss the current challenges for successful precision farming in practice through case studies of farmers using the technologies in the dairy, beef, and sheep sectors. These case studies highlight the need for greater emphasis on the "user" phase of the technology development cycle. The concept of technological innovation systems provides a path forward for agricultural engineers where a more holistic approach is taken to technology development, and where the processes of learning, knowledge creation, and ongoing adaptation occur alongside new technology design. The value proposition for farmers needs to be clear to encourage them to invest time and money in not only the purchase and installation of such technology, but also into the early learning that is required. There is a requirement for investment in human capital to support precision technologies, while also creating knowledge sharing structures to link farmers to the lessons learnt by others. [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]

Abstract: Degradation of coastal ecosystems in the Great Barrier Reef (GBR) lagoon, Australia, has been linked with increased land-based runoff of suspended solids, nutrients and pesticides since European settlement. This study estimated the increase in river loads for all 35 GBR basins, using the best available estimates of pre-European and current loads derived from catchment modelling and monitoring. The mean-annual load to the GBR lagoon for (i) total suspended solids has increased by 5.5 times to 17,000ktonnes/year, (ii) total nitrogen by 5.7 times to 80,000tonnes/year, (iii) total phosphorus by 8.9 times to 16,000tonnes/year, and (iv) PSII herbicides is 30,000kg/year. The increases in river loads differ across the 10 pollutants and 35 basins examined, reflecting differences in surface runoff, urbanisation, deforestation, agricultural practices, mining and retention by reservoirs. These estimates will facilitate target setting for water quality and desired ecosystem states, and enable prioritisation of critical sources for management. [Copyright &y& Elsevier]

Abstract: More than 2.5millionha of Eucalyptus globulus are now planted across the globe including approximately 500000ha in southern Australia. In this region average annual rainfall has declined since 1960 and this trend is predicted to continue in the coming decades. E. globulus is a premium species for paper manufacture and grows well under moderate seasonal water stress. The traits that underpin this rapid early growth also make the species vulnerable to prolonged water stress. We established nitrogen rate and nitrogen-by-stocking experiments in five 2-year-old E. globulus plantations along a climatic gradient in south-western Australia. We measured volume growth, predawn leaf water potential and leaf area index over 7 years or until the plantations were 9 years old. These data were used to explore the relationship between growth and water stress, to understand the mechanistic basis for the relationship and to identify best-bet management strategies for E. globulus plantations in southern Australia. Nearly all of the variation in volume growth rate between sites could be explained by a combination of climate wetness index and soil depth. There was a significant growth response to nitrogen at two low rainfall and one high rainfall site. There was no growth response to nitrogen on sites where total soil nitrogen in the top 0.1m of soil was more than 1.9mgg−1 and a very rapid increase in relative growth response below this threshold. The observed growth response to nitrogen was associated with an increase in water stress and on at least one site increased mortality. Matching the supply of nutrients to demand will maximise the growth at any site but this may increase the risk of drought death at water-limited sites. This will be exacerbated if forecasted changes in the climate of southern Australia are realised. Thinning to 600stemsha−1 significantly reduced the level of water stress experienced by E. globulus in Western Australia without significantly affecting end of rotation stand volume compared to unthinned stands. These results indicate that for a range of sites in south-western Australia a final stocking density of 600stemsha−1 coupled with application of fertiliser to maximise growth will minimise risk without sacrificing any of the site potential. [Copyright &y& Elsevier]

Identifying the erosion processes contributing to increased basin fine sediment yield is important for reducing downstream impacts on aquatic ecosystems. However, erosion rates are spatially variable, and much eroded sediment is stored within river basins and not delivered downstream. A spatially distributed sediment budget model is described that assesses the primary sources (hillslope soil erosion, gully and riverbank erosion) and sinks (floodplain and reservoir deposition) of fine sediment for each link in a river network. The model performance is evaluated in a 17,000-km2 basin in south-east Australia using measured suspended sediment yields from eight catchments within the basin, each 100–700km2 in area. Spatial variations within the basin in yield and area-specific yield were reliably predicted. Observed yields and area-specific yields varied by 17-fold and 15-fold respectively between the catchments, while predictions were generally within a factor of 2 of observations. Model efficiency at predicting variations in area-specific yield was good outside forested areas (0.58), and performance was weakly sensitive to parameter values. Yields from forested areas were under-predicted, and reducing the predicted influence of riparian vegetation on bank erosion improved model performance in those areas. The model provided more accurate and higher resolution predictions than catchment area interpolation of measured yields from neighbouring river basins. The model is suitable for guiding the targeting of remediation measures within river basins to reduce downstream sediment yields. [Copyright &y& Elsevier]

While channel erosion is recognised as a major, often-dominant, source of river sediment, channel geometry and its change remain impractical to measure for anything but small experimental watersheds. Designing remediation strategies in landscapes affected by channel erosion requires information on the extent and location of current incised channel features, as well as a method to determine locations where incision may occur in the future. We present a multi-resolution algorithm that uses topographic information to concurrently map both existing incised landform elements and areas at risk of future incision. The former uses elevation, slope and profile curvature to identify topographic signatures of incised landform elements, and the latter uses landscape position, topographic wetness index and stream power index to isolate areas likely susceptible to future incision. We aimed to develop a computationally efficient method capable of operating across a broad range of landscapes. The algorithm was tested in three contrasting environments in eastern Australia with promising results. Sensitivity analysis indicates the method performs reasonably consistently across landscapes, but that outputs become more sensitive as the average slope of the landscape increases. A comparison between cleared and uncleared hillsides suggested that areas indicated at risk of future incision are plausible, and that cleared areas were more susceptible to channel incision. The only required input is a digital elevation model, and outputs can provide a rapid visual assessment of landscapes affected by incisional erosion. This technique enables the identification of gully erosion and the planning of remediation works across landscapes of thousands of square kilometres. It may assist in prioritisation of works and further insights into the processes associated with channel incision. • A method to concurrently map gullies and areas at risk of incision is presented. • The method enables an assessment of the potential for future channel development. • A digital elevation model is the only required input to run the open-source algorithm. • The method facilitates mapping of gullies across large areas. [ABSTRACT FROM AUTHOR]

Nearly 15 percent of workers in Australia live within a cyclable distance of their workplace but commute by private vehicles. Adopting the concept of cycling dissonance, we investigate the role of modality styles alongside built environment characteristics on commuters' travel mode choice for work trip chains. Using travel survey data and employing latent class choice modelling, results reveal two modality styles: (1) driving and walking oriented commuters; and (2) multimodal commuters. Commuters in the first modality style are mostly those who are aged 20 and above, have dependent children, own a motor vehicle(s), and are insensitive to trip chain complexity. The second modality style captures those who are younger, relatively inelastic to mode-specific travel time, and prefer sustainable transport including cycling for non-complex trip chains. High population density around home residences encourages the choice of cycling for commuters falling within the second modality style, indicating that they are the most likely candidates to undergo a mode shift from motorised transport to cycling. Findings enable us to distinguish commuters by their latent modal preference and better identify the spatial concentrations of candidate commuters with a greater potential for a mode shift, which may be helpful for prioritising cycling-supportive investment in policymaking. • Cycling dissonance used to capture non-cycling commuters. • Delineated modality styles in terms of travel modes and the built environment. • Mapped spatial clusters of commuters with different modality styles. • Revealed the modality style with greatest mode shift potential. [ABSTRACT FROM AUTHOR]

Commuters who live spatially proximate to their workplaces have the greatest potential to commute by cycling. Employing the concept of cycling dissonance— the mismatch of individuals who can commute by cycling given a cyclable distance between home and the workplace but travel by other modes —we examine the role of the street-scale environment in commuters' travel mode choice via a lens of modality styles. Drawing on the household travel survey data for Greater Brisbane, Australia and employing latent class choice modelling, two modality styles are unveiled: (1) car oriented; and (2) multimodal but walking averse. Commuters falling within the first modality style are typically middle-aged adults from households that own motor vehicles. Commuters belonging to the second modality style are younger, less likely to own a car, relatively inelastic to travel time, and less sensitive to street-scale environment settings. While commuters in the first modality style predominantly use cars to commute, their propensity for cycling-to-work would likely be markedly higher if the street-scale environment of their route to work could include cycleways and is relatively flat. Those belonging to the first modality style have a higher potential to shift mode from car to cycling given their likely response to shifts in the street-scale environment. By mapping the residential locations of the two modality style groups across the case study context, we spatially delineated locales where cycling dissonance could be reduced by improving the street-scale environment, which has the capacity to inform place-based strategies in prioritising cycling-supportive investment. • Cycling dissonance employed to capture non-cycling commuters with cycling potential. • Revealed the association between the street-scale environment and travel mode choice. • Delineated the modality style with the greatest potential of shifting mode to cycling. • Identified part road network that might most need cycling-supportive investment. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews water-borne soil erosion in Australia in the context of current environmental policy needs. Sustainability has emerged as a central tenet of environmental policy in Australia and water-borne hillslope soil erosion rates are used as one of the indicators of agricultural sustainability in State of the Environment reporting. We review attempts to quantify hillslope erosion rates over Australia and we identify areas at risk of exceeding natural baseline rates. We also review historical definitions of sustainable, or ‘tolerable’ erosion rates, and how to set these rates. There are many ways to estimate hillslope erosion and these can create confusing results. Moreover their application for land management purposes requires nuanced interpretations that ultimately depend on the desired objective of decision-makers. Soil is the earth surficial material that serves as a medium for plant growth and the notion of tolerable soil erosion arose historically to assess the impact of soil loss on agricultural uses. However now that the impact of erosion on aquatic ecosystems been recognized as a major concern for Australia, the concept of tolerable erosion needs to be revised. Here we discuss three definitions of tolerable soil erosion, following recent literature. We derive estimates of long-term agricultural sustainability based on natural soil production rates and discuss this in relation to other defined land-management objectives such as aquatic ecosystem health. We conclude that the desired objectives of land managers must be clearly articulated before questions of ‘where to invest to control erosion’ and ‘how to assess return-on-investment’ can be answered. [Copyright &y& Elsevier]

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]

• 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]