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Plant growth is influenced by interactions with neighbouring plants. The strength and direction of the cumulative neighbourhood effect on growth can depend on neighbour properties, such as their abundance, size and proximity, as well as the degree of similarity between interacting plants and their traits, which can be captured by the species identity of neighbours. Such interactions are also influenced by the local environmental conditions that are largely determined by climate. Because neighbour and climatic effects are typically explored in isolation, particularly in long‐lived species such as trees, it is unclear how the impacts of neighbours on plant growth shift in response to temporal variation in climatic conditions.Here, we explored how neighbouring plants impact the annual growth of two eucalypts, Eucalyptus delegatensis and Eucalyptus regnans, over three growing seasons in an experimental forest in south‐east Tasmania, Australia. We assessed whether eucalypt growth rates could be described by the number, size, proximity, and species identity of neighbours, and how the strength of this effect was influenced by the growing season climatic conditions.We found that climate and neighbouring plants had an interactive impact on eucalypt growth. Neighbours had a consistent, competitive effect on the growth of both eucalypts in all three growing seasons which was strongly related to the cumulative neighbourhood biomass. The identity of neighbours was important in determining E. regnans growth only, whereby distinguishing neighbours according to functional group best described growth. Over all three growing seasons, we predicted that, on average, neighbours reduced E. delegatensis and E. regnans mean annual growth by 60.5% and 48.4%, respectively. However, the strength of the competitive effect of neighbours on eucalypt growth was related to growing season climate, being strongest when conditions were hot and dry and weakest in cool, wet conditions.Synthesis: Given the consistent results observed in two co‐occurring eucalypts, our findings suggest that drier and hotter climatic conditions increase the strength of competitive effects on tree growth. This has implications for future forest productivity given projected increased temperatures and variation in rainfall patterns globally. [ABSTRACT FROM AUTHOR]

Interactions among neighbouring plants are key determinants of plant growth. To characterise the cumulative effect of all neighbours on the growth of a focal plant, neighbourhoods are often described by 'competition' indices. Common competition indices calculate the summed size of neighbour plants (focal‐independent index [FII]) whilst others include the summed ratio of the neighbour size relative to focal plant size (focal dependent). A frequently overlooked statistical artefact is that focal‐dependent indices (FDIs) may lead to biased estimates of neighbourhood effects on plant growth when growth is size dependent.Here, we conduct a literature search to determine the most common index types used to explain neighbour effects on tree growth. We then assess the ability of two common index types—focal dependent and focal independent—to correctly infer neighbourhood effects in (1) observations of tree growth in an experimental forest in south‐east Tasmania, Australia, and (2) an artificially created dataset where tree growth is unrelated to the neighbourhood.Both indices detected the competitive neighbourhood effect on tree growth observed in our own dataset but differed in their conclusion regarding neighbour effects in the simulated data. Despite the simulated dataset being generated so there was no relationship between tree growth and their neighbourhood, the FDI detected strong, competitive neighbourhood effects when intrinsic growth was incorrectly related to tree size. In contrast, when we considered the FII as the neighbourhood metric, we correctly did not detect any neighbourhood effects in the simulated data regardless of how size‐dependent growth was described.Synthesis. 'Competition' indices are a useful method to characterise the cumulative neighbourhood effect on plant growth; however, we demonstrate that indices which include the size of the focal plant in their calculation can be biased by an inherent relationship between tree growth and initial size. Whilst this bias typically overstates the strength of competition in determining focal tree growth, we show that it can be mitigated by correctly describing intrinsic growth. We discuss the limitations of both index types, provide recommendations for performing statistical modelling and outline how to check for accurate neighbour inference. [ABSTRACT FROM AUTHOR]

Major aridification events in Australia during the Pliocene may have had significant impact on the distribution and structure of widespread species. To explore the potential impact of Pliocene and Pleistocene climate oscillations, we estimated the timing of population fragmentation and past connectivity of the currently isolated but morphologically similar subspecies of the widespread brushtail possum (Trichosurus vulpecula). We use ecological niche modeling (ENM) with the current fragmented distribution of brushtail possums to estimate the environmental envelope of this marsupial. We projected the ENM on models of past climatic conditions in Australia to infer the potential distribution of brushtail possums over 6 million years. D‐loop haplotypes were used to describe population structure. From shotgun sequencing, we assembled whole mitochondrial DNA genomes and estimated the timing of intraspecific divergence. Our projections of ENMs suggest current possum populations were unlikely to have been in contact during the Pleistocene. Although lowered sea level during glacial periods enabled connection with habitat in Tasmania, climate fluctuation during this time would not have facilitated gene flow over much of Australia. The most recent common ancestor of sampled intraspecific diversity dates to the early Pliocene when continental aridification caused significant changes to Australian ecology and Trichosurus vulpecula distribution was likely fragmented. Phylogenetic analysis revealed that the subspecies T. v. hypoleucus (koomal; southwest), T. v. arnhemensis (langkurr; north), and T. v. vulpecula (bilda; southeast) correspond to distinct mitochondrial lineages. Despite little phenotypic differentiation, Trichosurus vulpecula populations probably experienced little gene flow with one another since the Pliocene, supporting the recognition of several subspecies and explaining their adaptations to the regional plant assemblages on which they feed. [ABSTRACT FROM AUTHOR]

Summary: Vulnerability to xylem cavitation is a strong predictor of drought‐induced damage in forest communities. However, biotic features of the community itself can influence water availability at the individual tree‐level, thereby modifying patterns of drought damage.Using an experimental forest in Tasmania, Australia, we determined the vulnerability to cavitation (leaf P50) of four tree species and assessed the drought‐induced canopy damage of 2944 6‐yr‐old trees after an extreme natural drought episode. We examined how individual damage was related to their size and the density and species identity of neighbouring trees.The two co‐occurring dominant tree species, Eucalyptus delegatensis and Eucalyptus regnans, were the most vulnerable to drought‐induced xylem cavitation and both species suffered significantly greater damage than neighbouring, subdominant species Pomaderris apetala and Acacia dealbata. While the two eucalypts had similar leaf P50 values, E. delegatensis suffered significantly greater damage, which was strongly related to the density of neighbouring P. apetala. Damage in E. regnans was less impacted by neighbouring plants and smaller trees of both eucalypts sustained significantly more damage than larger trees.Our findings demonstrate that natural drought damage is influenced by individual plant physiology as well as the composition, physiology and density of the surrounding stand. [ABSTRACT FROM AUTHOR]

Background: Patient perceptions of iron deficiency and efficacy of iron therapy may differ from the interpretations of doctors. Qualitative investigation at an individual level related may help define patient expectations and therapeutic targets. Therefore, we aimed to explore this concept in exercising females of reproductive age.Methods: Exercising females (n = 403) who either (a) were currently experiencing iron deficiency, or (b) have experienced iron deficiency in the past were included. A survey comprising open-ended text response questions explored three 'domains': (1) the impact of iron deficiency, (2) the impact of iron tablet supplementation (where applicable), and (3) the impact of iron infusion treatment (where applicable). Questions were asked about training, performance, and recovery from exercise. Survey responses were coded according to their content, and sentiment analysis was conducted to assess responses as positive, negative, or neutral.Results: Exercising females showed negative sentiment toward iron deficiency symptoms (mean range = − 0.94 to − 0.81), with perception that fatigue significantly impacts performance and recovery. Iron therapies were perceived to improve energy, performance, and recovery time. Participants displayed a strong positive sentiment (mean range = 0.74 to 0.79) toward iron infusion compared to a moderately positive sentiment toward oral iron supplementation (mean range = 0.44 to 0.47), with many participants perceiving that oral iron supplementation had no effect.Conclusion: In Australia, women prefer an iron infusion in treatment of iron deficiency compared to oral iron. [ABSTRACT FROM AUTHOR]

Background and aims: High quality clinical research that addresses important questions requires significant resources. In resource-constrained environments, projects will therefore need to be prioritized. The Australia and New Zealand Musculoskeletal (ANZMUSC) Clinical Trials Network aimed to develop a stakeholder-based, transparent, easily implementable tool that provides a score for the 'importance' of a research question which could be used to rank research projects in order of importance. Methods: Using a mixed-methods, multi-stage approach that included a Delphi survey, consensus workshop, inter-rater reliability testing, validity testing and calibration using a discrete-choice methodology, the Research Question Importance Tool (ANZMUSC-RQIT) was developed. The tool incorporated broad stakeholder opinion, including consumers, at each stage and is designed for scoring by committee consensus. Results: The ANZMUSC-RQIT tool consists of 5 dimensions (compared to 6 dimensions for an earlier version of RQIT): (1) extent of stakeholder consensus, (2) social burden of health condition, (3) patient burden of health condition, (4) anticipated effectiveness of proposed intervention, and (5) extent to which health equity is addressed by the research. Each dimension is assessed by defining ordered levels of a relevant attribute and by assigning a score to each level. The scores for the dimensions are then summed to obtain an overall ANZMUSC-RQIT score, which represents the importance of the research question. The result is a score on an interval scale with an arbitrary unit, ranging from 0 (minimal importance) to 1000. The ANZMUSC-RQIT dimensions can be reliably ordered by committee consensus (ICC 0.73–0.93) and the overall score is positively associated with citation count (standardised regression coefficient 0.33, p<0.001) and journal impact factor group (OR 6.78, 95% CI 3.17 to 14.50 for 3rd tertile compared to 1st tertile of ANZMUSC-RQIT scores) for 200 published musculoskeletal clinical trials. Conclusion: We propose that the ANZMUSC-RQIT is a useful tool for prioritising the importance of a research question. [ABSTRACT FROM AUTHOR]

Productive water use can be an effective adaptation strategy for improving crop performance. A 2-year field study was undertaken in 2018 and 2019 to investigate the effect of sowing date and genotype on water-use efficiency of lentils grown in diverse locations in Australia. Above-ground dry matter accumulation, grain yield, soil evaporation, water use, and water-use efficiency (WUE) were measured and/or calculated at crop maturity. Early sowing (SD1/mid-April), late maturity and supplementary irrigation increased water use. The long growth cycle resulting from early sowing influenced WUE for dry matter production and grain yield. WUE ranged from 10.5 to 18.8 kg dry matter ha−1 mm−1 (WUEET (evapotranspiration)) and 17.1 to 28.3 kg dry matter ha−1 mm−1 (WUET (transpiration)) for dry matter production. For grain yield, WUE ranged from 2.11 to 5.65 kg grain ha−1 mm−1 (WUEET) and 4.71 to 9.19 kg grain ha−1 mm−1 (WUET). There was more water loss through soil evaporation in SD1 compared to the other sowing dates. Excessive or limited availability of water did not translate to more dry matter accumulation and grain yield. The study concluded that SD1 gives the maximum water productivity for biomass, and SD2 (end of April) and SD3 (mid-May) for grain yield. [ABSTRACT FROM AUTHOR]

During the reproductive stage, chilling temperatures and frost reduce the yield of chickpea and limit its adaptation. The adverse effects of chilling temperature and frost in terms of the threshold temperatures, impact of cold duration, and genotype-by-environment-by-management interactions are not well quantified. Crop growth models that predict flowering time and yield under diverse climates can identify combinations of cultivars and sowing time to reduce frost risk in target environments. The Agricultural Production Systems Simulator (APSIM-chickpea) model uses daily temperatures to model basic crop growth but does not include penalties for either frost damage or cold temperatures during flowering and podding stages. Regression analysis overcame this limitation of the model for chickpea crops grown at 95 locations in Australia using 70 years of historic data incorporating three cultivars and three sowing times (early, mid, and late). We modified model parameters to include the effect of soil water on thermal time calculations, which significantly improved the prediction of flowering time. Simulated data, and data from field experiments grown in Australia (2013 to 2019), showed robust predictions for flowering time (n = 29; R2 = 0.97), and grain yield (n = 22; R2 = 0.63–0.70). In addition, we identified threshold cold temperatures that significantly affected predicted yield, and combinations of locations, variety, and sowing time where the overlap between peak cold temperatures and peak flowering was minimal. Our results showed that frost and/or cold temperature–induced yield losses are a major limitation in some unexpected Australian locations, e.g., inland, subtropical latitudes in Queensland. Intermediate sowing maximise yield, as it avoids cold temperature, late heat, and drought stresses potentially limiting yield in early and late sowing respectively. [ABSTRACT FROM AUTHOR]

Aim: Environmental DNA (eDNA) metabarcoding has demonstrated its applicability as a highly sensitive biomonitoring tool across small spatial and temporal scales in marine ecosystems. However, it has rarely been tested across large spatial scales or biogeographical barriers. Here, we scale up marine eDNA metabarcoding, test its ability to detect a major marine biogeographic break and evaluate its use as a regional biomonitoring tool in Australia. Location: North‐western Australia (NWA). Methods: We applied metabarcoding assays targeting the mitochondrial 16S rRNA and CO1 genes to 284 surface seawater eDNA samples collected from 71 mid‐shelf, inshore, coastal and nearshore estuarine sites over 700 km of the NWA coastline. Results: Metabarcoding detected a wide range of bony fish (404 taxa), elasmobranchs (44) and aquatic reptiles (5). We detected bioregional and depth differentiation within inshore bony fish communities. These findings support the presence of a marine biogeographic break, which is purported to occur in the vicinity of Cape Leveque, demarcating the border between the Kimberley and Canning bioregions. Inshore bony fish and elasmobranch communities, as well as coastal bony fish assemblages, were additionally found to differ between the South and North Kimberley regions suggesting previously unrecognized subregional differentiation amongst these taxa. The overall compositional data have been used to update distribution information for a number of endangered, elusive and data‐deficient taxa, including sawfish (family: Pristidae), northern river shark (Glyphis garricki) and wedgefish (genus: Rhynchobatus). Main conclusions: eDNA metabarcoding demonstrated a high level of sensitivity that was able to discern fine‐scale patterns across the large‐scale, remote and oceanographically complex region of North‐western Australia. Importantly, this study highlights the potential of integrating broad‐scale eDNA metabarcoding alongside other baseline surveys and long‐term monitoring approaches, which are crucial for the sustainable management and conservation of marine biodiversity in this unique marine region. [ABSTRACT FROM AUTHOR]