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Recent global fire activity has highlighted the importance of understanding fire dynamics across time and space, with records of past fire (palaeofire) providing valuable insights to inform current and future management challenges. New records from the recent increase in palaeofire studies from Australia and surrounds have not been captured in any database for broader comparisons, and Australasia is poorly represented in current international databases used for global modelling of palaeofire trends. These problems are addressed by SahulCHAR, a new collection of sedimentary charcoal and black carbon records from Sahul (Australia, New Guinea, and offshore islands) and New Zealand. Data are stored in the OCTOPUS relational database platform, with a structure designed for compatibility with the existing Global Paleofire Database. Metadata are captured at site-level and observation-level, with observations including age determinations and charcoal or black carbon data. SahulCHAR Version 1 contains 687 records of charcoal or black carbon, including digitized data, unchanged and modified records from the Global Paleofire Database, and original author-submitted data. SahulCHAR is a much-needed update on past regional palaeofire compilations that will also provide greater representation of records from Sahul and New Zealand in future global syntheses. [ABSTRACT FROM AUTHOR]

Background: As fire regimes continue to evolve in response to climate change, understanding how fire characteristics have responded to changes in the recent past is vital to inform predictions of future fire events. Aims and methods: Using Fourier Transform Infrared (FTIR) spectroscopy, we assessed how fire intensity has changed in two fire-prone landscapes in south-eastern Australia: (1) the Blue Mountains; and (2) Namadgi National Park during the past 3000 years. Key results: Higher aromatic/aliphatic ratios suggest increased high-intensity fire frequency in sediments at the surface of both cores. Increases in the frequency of extreme drought periods, coupled with the change in vegetation and anthropogenic ignitions following colonisation, could have increased the frequency of high-intensity fires in the past ~200 years. Conclusions: FTIR spectroscopy can be used in sediment deposits to infer that the frequency of high-intensity fire events has increased in the past 200 years compared to the previous ~3000 years. Implications: These results are important for understanding how past fire regimes have responded to climate, people and vegetation shifts in the past ~3000 years and can be used to inform models for future predictions and management strategies. Fourier Transform Infrared (FTIR) spectroscopy was applied to sediment deposits in southeastern Australia. The aromatic/aliphatic ratio was used as a proxy for high-intensity fires. The increased frequency of high-intensity fire events could result from interactions between climate, people, and vegetation. The existing fire record was extended by centuries to millennia. [ABSTRACT FROM AUTHOR]

Australian conservation targets commonly focus on preserving a vaguely defined ecological baseline, often conceptualised as a pre-European, 'natural' state. For instance, environmental legislation protects 'Endangered Ecological Communities' (EECs), which purportedly represent remnants of naturally occurring biota. However, EECs are often classified without long-term data, making it unclear as to whether the community being protected is indeed 'natural'. In this essay, we use history, ecology, and geography to map the long-term socio-environmental evolution of Sydney's freshwater wetland EECs, which were once key features of Australia's biggest city. Our data show that today's remnant wetlands are different from those of the early 1800s, highlighting how quickly landscapes can be misremembered. We encourage a reimagining of these wetlands not as snapshots of the past, but as human-impacted places with educational, ecological and historical importance. Our work emphasises the relevance of long-term, cross-disciplinary data for effective conservation, while highlighting limitations in post-colonial land management. [ABSTRACT FROM AUTHOR]

This study investigated the effects a dilute solution of bleach (4% sodium hypochlorite), has on charcoal. We were particularly interested in considering if charcoal formed under different conditions of pyrolysis was differentially affected by this treatment, which is commonly used for the quantification of charcoal in sediments. We first produced a series of charcoal samples, under laboratory conditions (at temperatures between 250°C and 800°C and under oxygen limited conditions) and then measured total surface area of charcoal before and after treatment in a solution of 4% bleach. We found that charcoal formed ⩽400°C showed nearly complete bleaching after 24 h, while high temperature charcoal (>400°C) was much more resistant. These results indicate this treatment bleaches charcoal formed at lower temperatures: this means particles charred at low temperature may not be quantified in common optical counting or image analysis methods. This could have serious ramifications for sediment-based paleofire research as low intensity fire may be lost from a record, and the resulting fire history biased towards high intensity (high temperature) fires. Our findings suggest the need for a new, non-destructive method for extracting charcoal from sediment. [ABSTRACT FROM AUTHOR]

Brain injury can cause many distinct types of visual impairment in children, but these deficits are difficult to quantify due to co-morbid deficits in communication and cognition. Clinicians must instead rely on low-resolution, subjective judgements of simple reactions to handheld stimuli, which limits treatment potential. We have developed an interactive assessment program called the Visual Ladder, which uses gaze-based responses to intuitive, game-like tasks to address the lack of broad-spectrum quantified data on the visual abilities of children with brain injury. Here, we present detailed metrics on eye movements, field asymmetries, contrast sensitivity, and other critical visual abilities measured longitudinally using the Ladder in hospitalized children with varying types and degrees of brain injury, many of whom were previously considered untestable. Our findings show which abilities are most likely to exhibit recovery and reveal how distinct patterns of task outcomes defined unique diagnostic clusters of visual impairment., Competing Interests: Notice of competing interests Authors GTP and SWJM are co-inventors on US patent US20230414092A1, which describes the hardware and software for the Gradiate contrast sensitivity task that forms one part of the assessment program used in this study.