Search Results (66)

Light Detection and Ranging (LiDAR) provides three-dimensional information that can be used to extract tree parameter measurements such as height (H), canopy volume (CV), canopy diameter (CD), canopy area (CA), and tree stand density. LiDAR data does not directly give diameter at breast height (DBH), an important input into allometric equations to estimate biomass. The main objective of this study is to estimate tree DBH using existing allometric models. Specifically, it compares three global DBH pantropical models to calculate DBH and to estimate the aboveground biomass (AGB) of the Lake Broadwater Forest located in Southeast (SE) Queensland, Australia. LiDAR data collected in mid-2022 was used to test these models, with field validation data collected at the beginning of 2024. The three DBH estimation models—the Jucker model, Gonzalez-Benecke model 1, and Gonzalez-Benecke model 2—all used tree H, and the Jucker and Gonzalez-Benecke model 2 additionally used CD and CA, respectively. Model performance was assessed using five statistical metrics: root mean squared error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), percentage bias (MBias), and the coefficient of determination (R²). The Jucker model was the best-performing model, followed by Gonzalez-Benecke model 2 and Gonzalez-Benecke model 1. The Jucker model had an RMSE of 8.7 cm, an MAE of −13.54 cm, an MAPE of 7%, an MBias of 13.73 cm, and an R² of 0.9005. The Chave AGB model was used to estimate the AGB at the tree, plot, and per hectare levels using the Jucker model-calculated DBH and the field-measured DBH. AGB was used to estimate total biomass, dry weight, carbon (C), and carbon dioxide (CO₂) sequestered per hectare. The Lake Broadwater Forest was estimated to have an AGB of 161.5 Mg/ha in 2022, a Total C of 65.6 Mg/ha, and a CO₂ sequestered of 240.7 Mg/ha in 2022. These findings highlight the substantial carbon storage potential of the Lake Broadwater Forest, reinforcing the opportunity for landholders to participate in the carbon credit systems, which offer financial benefits and enable contributions to carbon mitigation programs, thereby helping to meet national and global carbon reduction targets. Full article

The suite of fungi that associate with mosses, bryophilous fungi, can be explored further to provide insights into the symbiotic functionality of mosses as well as the ecosystems in which they reside. So far, in-depth studies on the taxonomic diversity, ecology, and physiological functions of bryophilous fungi associated with the Australasian moss species Leucobryum candidum are lacking. To generate information on the physiology, biology, and ecology of these organisms and their interactions with the moss host, the combined use of selective isolation and molecular characterisation of the fungal associates was carried out. Once the pure cultures of the fungal associates were obtained, a bioactivity assay was used to investigate the effect of fungal metabolites on moss growth in vitro. Overall, L. candidum species collected from six different locations within Southeast Queensland exposed to different environmental parameters were found to have a highly diverse community of fungal species from 10 orders and 17 families. A total of 25 of the 33 isolates that were identified using molecular sequencing techniques were unique species, confirming high beta diversity of the fungal associates of L. candidum collected from coastal, forest, and urban environments in Southeast Queensland. The highest numbers of culturable isolates came from coastal and forest sites. Urban sites accounted for the lowest numbers of culturable isolates. The taxonomic matches for these associates were known to have diverse endophytic, saprophytic, and parasitic roles within vascular plants. Selected moss samples were inoculated with fermentation extracts of fungal isolates (USC-F426 and USC-F427) and their effects on the moss samples were observed for any change in heights, weights, diameters, and morphological characteristics. A significant (p ≤ 0.05) difference in the heights of the in vitro-assessed L. candidum between treatments was observed. No significant differences, however, were seen between the weights and diameters and no discernible host symptoms were detected, other than a few morphological change observations. Full article

Groundwater levels were monitored before, during and after groundwater pumping to understand the impacts of groundwater extraction on Abercorn Spring, a recharge spring in the Great Artesian Basin (GAB) in southeast Queensland, Australia. We measured the wetted area of the spring during this time to understand if changes in hydrology affected the water available for vegetation communities. Sustained groundwater extraction >20 km upgradient of the spring resulted in (1) rapid drawdown of the source aquifer, causing a reduction in aquifer pressure; (2) a small decline (0.35 m) in water level at the spring; and (3) a significant change (p = 0.0001) in wetted area in winter. Recovery of water levels and wetted area of the mound spring took over three years after pumping ceased. Our study demonstrated that significant changes to the wetted area occurred with only a minimal drawdown at the springs. Abercorn Springs have a natural low variability in water level (<0.2 m), implying a stable and predictable biological community. This natural range is less than half the water level change that is currently considered for impact assessment in artesian springs in the Queensland section of the GAB, highlighting the need to incorporate updated information to inform future management of both recharge and discharge springs. In the case of Abercorn Springs, long-term monitoring and research have led to refinement of license conditions for groundwater extraction, thereby mitigating further impacts to the springs and demonstrating adaptive management. Full article

Rural public transport networks face significant challenges, often characterised by suboptimal service quality. With advancements in technology, various applications have been explored to address these issues. Autonomous Demand-Responsive Transits (ADRTs) represent a promising solution that has been investigated over recent years. Their potential to enhance the overall quality of transport systems and promote sustainable transportation is well-recognised. In our research study, we evaluated the viability of ADRTs for rural networks. Our methodology focused on two primary areas: the suitability of ADRTs (considering vehicle type, service offerings, trip purposes, demographic groups, and land use) and the broader impacts of ADRTs (including passenger performance, social impacts, and environmental impacts). Perceptions of ADRT suitability peaked for university precincts and 24/7 operations. However, they were less favoured by mobility-disadvantaged groups (disabled, seniors, and school children). We also examined demographic heterogeneity and assessed the influence of demographic factors (age, gender, education, occupation, household income level, and disability status) on the implementation of ADRTs in rural settings. The findings delineate the varied perceptions across these socio-demographic strata, underscoring the necessity for demographic-specific trials. Consequently, we advocate for the implementation of ADRT services tailored to accommodate the diverse needs of these demographic cohorts. Full article

The eastern barn owl (Tyto javanica), a sub-group of Tyto alba, the most common species of owl in the world, is classified as “of least concern” under Queensland (Australia) legislation but appears to be affected by urban development. Between August 2010 and December 2021, 412 wild eastern barn owls were presented for treatment to the Currumbin Wildlife Hospital. A retrospective study of their medical records shows a strong association between the season and the number of admissions, with a combined total of 80% of admissions occurring in winter and spring (the breeding season for this species) in southeast Queensland. There was no significant association between age and admissions. The most common diagnosis was traumatic injuries, especially in winter and spring. Of all admissions, 46.61% died or were euthanized, 36.17% were transferred to wildlife carers, and 13.83% were discharged from the hospital. We postulate that the breeding season results in an increase in the owls’ activity, in turn resulting in greater risk exposure and increased admissions to veterinary clinics. These findings confirm that and thus provide information about the vulnerability of this species to anthropogenic activities and the implications for outcomes of injured owls. Full article

Introduction: Resource trade-offs are a universal feature of decision-making in healthcare. Public funding for home care is an example of a complex resource allocation decision, requiring balance between the needs of the individual and the capacity of the welfare system to meet those needs across the population. Under consumer-directed care policies, responsibility for resource allocation decisions rests with the care recipient, but there is no existing measure of allocative efficiency resulting from these consumer-led decisions. Our research considers resource allocation decisions by home care package recipients under consumer-directed care and evaluates the consistency of consumer-directed resource allocation with medically identified recommendations. Method: Retrospective cohort analysis of twenty home care package resource allocations made by home care package recipients in South-East Queensland, compared to associated medically identified needs and discussions with a potential service provider. Findings: Resource allocation decisions in the Australian home care setting are complex, multi-faceted, and made in highly uncertain environments. There are significant differences between services and equipment recommendations made by assessment teams, service providers, and home care recipient choices. Discussion: Awareness of the decision-making process and resulting decisions provides a foundation for future research to simplify decision-making for home care package recipients without sacrificing autonomy, leading to improved resource allocation efficiency and home care program outcomes. Conclusion: Consumer-directed care is a globally popular policy position to allocate public funds related to health care needs, despite uncertainty around the impact of this policy on program outcomes. Our analysis suggests further understanding of factors influencing resource allocation decisions is needed to define appropriate supports for effective decision-making in home care resource allocation, and further research effort is required to determine efficient resource allocation to inform policy changes, irrespective of the decision-maker. Full article

Humpback whales (Megaptera novaeangliae) migrate annually along the east coast of Australia, utilizing various habitats, including open embayments such as the Gold Coast bay (GCB) in southeast Queensland, for resting and social behaviors. While their migration is well-documented, the influence of oceanographic factors such as the East Australian Current (EAC)—a warm ocean current near the GCB—on humpback whale counts nearshore is not well understood. This study aims to assess the regional distribution of humpback whales in the GCB over consecutive years and investigate how dynamic environmental factors, such as the proximity of the EAC’s inner edge to shore and sea surface temperature (SST), affect the distribution and migration patterns of humpback whales. We employed citizen science data to obtain humpback whale sightings and applied generalized additive models (GAM) to evaluate the effects of environmental variables on humpback whale counts. Results suggested that shifts in EAC proximity and SST significantly influence humpback whale presence in the GCB, indicating that oceanographic features may guide migratory pathways and aggregation patterns. These findings improve our understanding of how climatic factors affect coastal humpback whale distributions, providing insights relevant to management and abundance estimates. Full article

Highly effective direct-acting antiviral (DAA) therapies for hepatitis C (HCV) have been available in Australian prisons since 2016. To address treatment interruption following release from prisons, the Queensland Injector’s Health Network (QuIHN) launched a Prison Transition Service (PTS) in south-east Queensland, Australia. Presently, the factors associated with continuity of post-release HCV care are poorly understood. The objective of this qualitative study was to explore the barriers and facilitators to HCV treatment among people recently released from prisons among PTS clients and stakeholders. Qualitative interviews were conducted with 27 participants, namely, 13 clients and 14 stakeholders (health and community support workers) of the PTS. We conducted thematic analysis using the framework of person-, provider-, and system-level barriers and facilitators. Person-level barriers included competing priorities post-release, while facilitators included self-improvement after treatment completion, preventing transmission to family, and social support. Provider-level treatment barriers included enacted stigma, limited prison health service capacity, and post-release health system challenges. Systemic barriers included stigma relating to HCV, injecting drug use, incarceration, and limited availability of harm reduction services. Policy changes and investment are required to expand HCV treatment in south-east Queensland prisons to facilitate patient navigation into community care. In terms of reducing stigma among health staff and the general community towards people with HCV, a history of incarceration and/or who inject drugs is crucial for improving treatment rates. Strategies such as peer-led or nurse-practitioner-led models of care may help improve treatment completion. Continuity of HCV treatment post-release from prisons is essential for Australia to meet the WHO’s 2030 HCV elimination target. Full article

Surveying and spatial science are experiencing a paradigm shift from traditional data outputs to more immersive and interactive formats, driven by the rise in Virtual Reality (VR). This study addresses the challenge of transforming UAV (Unmanned Aerial Vehicle)-acquired photogrammetry data into VR-compatible surfaces while preserving the accuracy and quality crucial to professional surveying. The study leverages Blender, an open-source 3D creation tool, to develop a procedural guide for creating VR-ready models from high-quality survey data. The case study focuses on silos located in Yelarbon, Southeast Queensland, Australia. UAV mapping is utilised to gather the data necessary for 3D modelling with a few minor alterations in the photo capturing angle and processing. Key findings reveal that while Blender excels as a visualisation tool, it struggles with geospatial precision, particularly when handling large numbers coming from coordinate systems, leading to rounding errors seen within the VR model. Blender’s strength lies in creating immersive experiences for public engagement but is constrained by its lack of capability to hold survey metadata, hindering its applicability for professional survey-grade outputs. The results highlight the need for further development into possible Blender plugins that integrate geospatial accuracy with VR outputs. This study underscores the potential of VR to enhance how survey data are visualised, offering opportunities for future innovations in both the technical and creative aspects of the surveying profession. Full article

Freshwater shortages in coastal regions are intensifying due to rapid urbanisation, economic growth, and climate variability, particularly in deltaic areas where rivers meet the sea. This study evaluates the feasibility of implementing a Coastal Reservoir (CR) as an innovative solution to increase freshwater availability without relying on desalination. Using the Brisbane River Estuary (BRE), Australia, as a case study, the research examines critical factors such as freshwater inflow, seawater intrusion, and reservoir volume requirements. A three-dimensional hydrodynamic model (MIKE 3) was calibrated and validated using observed data from the 2008 and 2011 flow events. Simulation results indicate that a freshwater discharge of 150 m³/s during a spring-neap tidal cycle effectively pushes saline water out of the estuary. The CR can store 300 GL/year of freshwater with 92% reliability, meeting Southeast Queensland’s (SEQ) annual water demand of 440 GL during drought conditions combined with existing infrastructure. During its initial filling phase, the CR can flush 95% of saltwater within 240 days, using a steady inflow of 150 m³/s. The findings demonstrate the technical feasibility of CRs as a sustainable and practical water management strategy for mitigating freshwater shortages in BRE and other similar coastal regions. Full article

The Biggenden gold-bearing Fe skarn deposit in southeast Queensland, Australia, is a calcic magnetite skarn that has been mined for Fe and gold (from the upper portion of the deposit). Skarn has replaced volcanic and sedimentary rocks of the Early Permian Gympie Group, which formed in different tectonic settings, including island arc, back arc, and mid-ocean ridge. This group has experienced a hornblende-hornfels grade of contact metamorphism due to the intrusion of the Late Triassic Degilbo Granite. The intrusion is a mildly oxidized I-type monzogranite that has geochemical characteristics intermediate between those of granitoids typically associated with Fe-Cu-Au and Sn-W-Mo skarn deposits. The skarn mineralogy indicates that there was an evolution from prograde to various retrograde assemblages. Prograde garnet (Adr_11-99Grs_1-78Alm_0-8Sps_0-11), clinopyroxene (Di_30-92Hd_7-65Jo_0-9), magnetite, and scapolite formed initially. Epidote and Cl-bearing amphibole (mainly ferropargasite) were the early retrograde minerals, followed by chlorite, calcite, actinolite, quartz, and sulfides. Late-stage retrograde reactions are indicated by the development of nontronite, calcite, and quartz. Gold is mainly associated with sulfide minerals in the retrograde sulfide stage. The fluids in equilibrium with the ore-stage calcites had δ¹³C and δ¹⁸O values that indicate deposition from magmatically derived fluids. The calculated δ¹⁸O values of the fluids in equilibrium with the skarn magnetite also suggest a magmatic origin. However, the fluids in equilibrium with epidote were a mixture of magmatic and meteoric water, and the fluids that deposited chlorite were at least partly meteoric. δD values for the retrograde amphibole and epidote fall within the common range for magmatic water. Late-stage chlorite was deposited from metasomatic fluids depleted in deuterium (D), implying a meteoric water origin. Sulfur isotopic compositions of the Biggenden sulfides are similar to other skarn deposits worldwide and indicate that sulfur was most probably derived from a magmatic source. Based on the strontium (⁸⁷Sr/⁸⁶Sr) and lead (²⁰⁶Pb/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁴Pb and ²⁰⁸Pb/²⁰⁴Pb) isotope ratios, the volcanic and sedimentary rocks of the Gympie Group may have contributed part of the metals to the hydrothermal fluids. Lead isotope data are also consistent with a close age relationship between the mineralization at Biggenden and the crystallization of the Degilbo Granite. Microthermometric analysis indicates that there is an overall decrease in fluid temperature and salinity from the prograde skarn to retrograde alterations. Fluid inclusions in prograde skarn calcite and garnet yield homogenization temperatures of 500 to 600 °C and have salinities up to 45 equivalent wt % NaCl. Fluid inclusions in quartz and calcite from the retrograde sulfide-stage homogenized between 280 and 360 °C and have lower salinities (5–15 equivalent wt % NaCl). In a favored genetic model, hydrothermal fluids originated from the Degilbo Granite at depth and migrated through the shear zone, intrusive contact, and permeable Gympie Group rocks and leached extra Fe and Ca and deposited magnetite upon reaction with the adjacent marble and basalt. Full article

The Australian lungfish, Neoceratodus forsteri, is one of the world’s oldest vertebrate lineages, with a slow life-history and threatened status, requiring immediate conservation efforts. The main threats to lungfish populations are degradation and availability of key macrophyte habitats, water regulation and flow modification. As this long-lived species (at least 77 years) has delayed maturity (mature at 10 years), field monitoring alone will not be enough to inform the challenge of ensuring sustainable populations. A stochastic metapopulation model was developed for the Burnett River (Southeast Queensland, Australia), an important habitat for the lungfish that is a highly regulated system with extensive water infrastructure. The model consists of three interacting populations, where the ecology and biology of the species were translated into an 80-year-class population projection matrix for each population, each with post-development streamflow, habitat and movement rules. The model highlights the longer-term interaction between dams and stream flows on habitat availability and subsequent recruitment. Through a pre-development streamflow, we quantify the impact of high regulation and development on the lungfish population in the Burnett River: a minor decline in the upstream population (e.g., 9.8% decline), a large decline in the middle population (64.2% decline), virtually no change in the downstream population (e.g., 1.2% decline) and a moderate decline in the overall metapopulation (e.g., 22.3% decline). The loss of spawning and feeding habitat remains the main reason for population decline, with implications that the loss will lead to greater pressure on remaining downstream habitat due to combined flow and dam effects and, in turn, to extended periods of recovery of spawning habitat. Our modeling approach substantially advances conservation management of this species, as it can be adapted to suit other populations in other river systems and used to test sensitivity to recovery actions. Full article

This study delves into the multifaceted realm of citrus fruits, exploring their significance and socioeconomic implications from their early introduction to Western Muslim and Renaissance gardens, tracing their journey throughout history. Employing a multidisciplinary approach, drawing from biological, archaeobotanical, iconographic, and textual sources, our study offers a comprehensive exploration of citrus symbolism and cultural significance, integrating historical, artistic, horticultural, and socioeconomic viewpoints. The genus Citrus (Rutaceae) comprises around thirty species and its natural habitat spans from the southern slopes of the Himalayas to China, Southeast Asia, nearby islands, and Queensland. Originating from only four of these species, humans have cultivated hundreds of hybrids and thousands of varieties, harnessing their culinary, medicinal, and ornamental potential worldwide. We delve into the symbolic value of citrus fruits, which have served as indicators of economic status and power. From their early presence in Mediterranean religious rituals to their depiction in opulent Roman art and mythical narratives like the Garden of the Hesperides, citrus fruits have epitomized luxury and desire. Christian lore intertwines them with the forbidden fruit of Eden, while Islamic and Sicilian gardens and Renaissance villas signify their prestige. We analyze diverse perspectives, from moralists to hedonists, and examine their role in shaping global agriculture, exemplified by rare varieties like aurantii foetiferi. Full article

Habitat loss due to wildfire is an increasing problem internationally for threatened animal species, particularly tree-dependent and arboreal animals. The koala (Phascolartos cinereus) is endangered in most of its range, and large areas of forest were burnt by widespread wildfires in Australia in 2019/2020, mostly areas dominated by eucalypts, which provide koala habitats. We studied the impact of fire and three subsequent years of recovery on a property in South-East Queensland, Australia. A classified Differenced Normalised Burn Ratio (dNBR) calculated from pre- and post-burn Sentinel-2 scenes encompassing the local study area was used to assess regional impact of fire on koala-habitat forest types. The geometrically structured composite burn index (GeoCBI), a field-based assessment, was used to classify fire severity impact. To detect lower levels of forest recovery, a manual classification of the multitemporal dNBR was used, enabling the direct comparison of images between recovery years. In our regional study area, the most suitable koala habitat occupied only about 2%, and about 10% of that was burnt by wildfire. From the five koala habitat forest types studied, one upland type was burnt more severely and extensively than the others but recovered vigorously after the first year, reaching the same extent of recovery as the other forest types. The two alluvial forest types showed a negligible fire impact, likely due to their sheltered locations. In the second year, all the impacted forest types studied showed further, almost equal, recovery. In the third year of recovery, there was almost no detectable change and therefore no more notable vegetative growth. Our field data revealed that the dNBR can probably only measure the general vegetation present and not tree recovery via epicormic shooting and coppicing. Eucalypt foliage growth is a critical resource for the koala, so field verification seems necessary unless more-accurate remote sensing methods such as hyperspectral imagery can be implemented. Full article

Immune-mediated polyarthritis (IMPA) has a relatively high relapse rate compared to other immune-mediated diseases. Leflunomide is frequently used to treat dogs with IMPA in conjunction with prednisolone. This retrospective cohort study aimed to evaluate the therapeutic efficacy of leflunomide as an adjunctive therapy to prednisolone in reducing relapse and mortality rates in dogs diagnosed with IMPA in Australia. The medical records of client-owned dogs diagnosed with IMPA at a specialist referral hospital in Southeast Queensland from 2017 to 2024 were reviewed. A total of 93 dogs were included in this study, divided into two groups based on the treatment received: Group PRED, consisting of 53 dogs treated with prednisolone as the sole immunosuppressive agent, and Group L+PRED, consisting of 40 dogs that received leflunomide as adjunctive therapy alongside prednisolone. Data collected included breed, age, weight, sex, serum C-reactive protein concentration, results of synovial fluid analysis and microbial culture, treatment protocol, relapse rates and time to relapse, and mortality rates. There was no difference in relapse or mortality rates, time to relapse, nor time to discontinue prednisolone between the PRED and L+PRED groups. The L+PRED group had higher body weights and lower prednisolone dose rate at discharge compared to those in the PRED group. This study demonstrated that the use of leflunomide as an adjunctive therapy to prednisolone for the treatment of dogs with IMPA had no improved outcomes, reduced relapse rates, or shortening in the duration of prednisolone therapy when compared to dogs receiving prednisolone monotherapy. Full article