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FURUOKA, FUMITAKA. "UNEMPLOYMENT DYNAMICS IN THE ASIA-PACIFIC REGION: A PRELIMINARY INVESTIGATION". Singapore Economic Review 62, n.º 05 (diciembre de 2017): 983–1016. http://dx.doi.org/10.1142/s021759081550085x.
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This study empirically examined unemployment dynamics in 12 countries in the Asia-Pacific region, namely, China, Hong Kong, Taiwan, South Korea, Japan, Indonesia, Malaysia, the Philippines, Singapore, Thailand, Australia and New Zealand. It used quarterly data on the unemployment rates from the first quarter of 1980 to the first quarter of 2013. This paper employed three different econometric methods, including the recently-developed powerful unit root test with structural break (Lee and Strazicich, 2003, 2004) and the nonlinear unit root test (Enders and Lee, 2012). The findings indicated that the unemployment rates in five countries of the region, namely, China, Taiwan, South Korea, the Philippines and Thailand, had highly dynamic labor markets in which higher-than-normal unemployment rates would revert to the normal level. The other seven Asia-Pacific countries had less dynamic labor markets. The findings of this study have some important policy implications.
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Ma, Le, Chunlu Liu y Anthony Mills. "Construction labor productivity convergence: a conditional frontier approach". Engineering, Construction and Architectural Management 23, n.º 3 (16 de mayo de 2016): 283–301. http://dx.doi.org/10.1108/ecam-03-2015-0040.
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Purpose – Understanding and simulating construction activities is a vital issue from a macro-perspective, since construction is an important contributor in economic development. Although the construction labor productivity frontier has attracted much research effort, the temporal and regional characteristics have not yet been explored. The purpose of this paper is to investigate the long-run equilibrium and dynamics within construction development under a conditional frontier context. Design/methodology/approach – Analogous to the simplified production function, this research adopts the conditional frontier theory to investigate the convergence of construction labor productivity across regions and over time. Error correction models are implemented to identify the long-run equilibrium and dynamics of construction labor productivity against three types of convergence hypotheses, while a panel regression method is used to capture the regional heterogeneity. The developed models are applied to investigate and simulate the construction labor productivity in the Australian states and territories. Findings – The results suggest that construction labor productivity in Australia should converge to stable frontiers in a long-run perspective. The dynamics of the productivity are mainly caused by the technology utilization efficiency levels of the local construction industry, while the influences of changes in technology level and capital depending appear limited. Five regional clusters of the Australian construction labor productivity are suggested by the simulation results, including New South Wales; Australian Capital Territory; Northern Territory, Queensland, and Western Australia; South Australia; and Tasmania and Victoria. Originality/value – Three types of frontier of construction labor productivity is proposed. An econometric approach is developed to identify the convergence frontier of construction labor productivity across regions over time. The specified model can provides accurate predictions of the construction labor productivity.
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Edmiston, Natalie, Erin Passmore, David J. Smith y Kathy Petoumenos. "Multimorbidity among people with HIV in regional New South Wales, Australia". Sexual Health 12, n.º 5 (2015): 425. http://dx.doi.org/10.1071/sh14070.
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Background Multimorbidity is the co-occurrence of more than one chronic health condition in addition to HIV. Higher multimorbidity increases mortality, complexity of care and healthcare costs while decreasing quality of life. The prevalence of and factors associated with multimorbidity among HIV positive patients attending a regional sexual health service are described. Methods: A record review of all HIV positive patients attending the service between 1 July 2011 and 30 June 2012 was conducted. Two medical officers reviewed records for chronic health conditions and to rate multimorbidity using the Cumulative Illness Rating Scale (CIRS). Univariate and multivariate linear regression analyses were used to determine factors associated with a higher CIRS score. Results: One hundred and eighty-nine individuals were included in the study; the mean age was 51.8 years and 92.6% were men. One-quarter (25.4%) had ever been diagnosed with AIDS. Multimorbidity was extremely common, with 54.5% of individuals having two or more chronic health conditions in addition to HIV; the most common being a mental health diagnosis, followed by vascular disease. In multivariate analysis, older age, having ever been diagnosed with AIDS and being on an antiretroviral regimen other than two nucleosides and a non-nucleoside reverse transcriptase inhibitor or protease inhibitor were associated with a higher CIRS score. Conclusion: To the best of our knowledge, this is the first study looking at associations with multimorbidity in the Australian setting. Care models for HIV positive patients should include assessing and managing multimorbidity, particularly in older people and those that have ever been diagnosed with AIDS.
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Yunusa, IAM, RH Sedgley y D. Tennant. "Evaporation from bare soil in south-western Australia - a test of two models using lysimetry". Soil Research 32, n.º 3 (1994): 437. http://dx.doi.org/10.1071/sr9940437.
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Physical models of the soil water balance components are useful where direct methods of determination are costly and time consuming. Information from such models is useful in developing more efficient soil and crop management practices. The simplicity of such models sometimes encourages their use in new regions without proper testing. In this study, two models of soil evaporation (Es), developed by Ritchie (Water Resour. Res., 1972, 8, 1204-13) and Boesten and Stroosnijder (Netherlands J. Agric. Sci., 1986, 34, 75-90) were evaluated in the dry mediterranean environment of the cereal belt of south-western Australia under a wide range of evaporative demand by using lysimetry. Both models treated soil evaporation as a two-stage process, but in the Ritchie model, second-stage evaporation varied with the square root of time, whereas in the Boesten and Stroosnijder model, Es varied with the square root of the potential evaporation (Eow). In the Boesten-Stroosnijder model, only the parameter � was stable over a wide range of potential evaporation Eow, whereas in the Ritchie model, both the parameters U and C varied with E(ow). However, interdependence between U and C was conservative, and higher values of U under low Eo were compensated by lower values of C, and vice versa. For the soil used in this study, the following values were found to be appropriate for the parameters: U, 4.7 mm; C, 4.0 mm1/2 ; and �, 1 . 5 mm1/2. For dry environments where seasonal Eo fluctuates widely, low U values and high C values are recommended. The Es estimated by the models agreed poorly with Es measured by the lysimeter on a daily basis. However, when the daily values were accumulated over periods of at least 6 days, good agreement was obtained, indicating that the errors associated with the daily estimates cancel out each other over time. Hence, both models gave satisfactory short-term and long-term predictions of Es, but in both cases variation between predicted and observed values was least in the Ritchie model. This is consistent with the conclusion from other studies in the region, which show that second stage evaporation dominates Es, and hence should depend more on soil moisture supply than on Eo.
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Hobday, Alistair J. y Janice M. Lough. "Projected climate change in Australian marine and freshwater environments". Marine and Freshwater Research 62, n.º 9 (2011): 1000. http://dx.doi.org/10.1071/mf10302.
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Changes in the physical environment of aquatic systems consistent with climate change have been reported across Australia, with impacts on many marine and freshwater species. The future state of aquatic environments can be estimated by extrapolation of historical trends. However, because the climate is a complex non-linear system, a more process-based approach is probably required, in particular the use of dynamical projections using climate models. Because global climate models operate on spatial scales that typically are too coarse for aquatic biologists, statistical or dynamical downscaling of model output is proposed. Challenges in using climate projections exist; however, projections for some marine and freshwater systems are possible. Higher oceanic temperatures are projected around Australia, particularly for south-eastern Australia. The East Australia Current is projected to transport greater volumes of water southward, whereas the Leeuwin Current on the western coast may weaken. On land, projections suggest that air temperatures will rise and rainfall will decline across much of Australia in coming decades. Together, these changes will result in reduced runoff and hence reduced stream flow and lake storage. Present climate models are particularly limited with regard to coastal and freshwater systems, making the models challenging to use for biological-impact and adaptation studies.
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Tiller, KG, LH Smith y RH Merry. "Accessions of atmospheric dust east of Adelaide, South Australia, and the implications for pedogenesis". Soil Research 25, n.º 1 (1987): 43. http://dx.doi.org/10.1071/sr9870043.
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Atmospheric dust and rainfall were collected at 19 locations within a 90 x 10 km study area extending eastwards from the coast near Adelaide, South Australia. Monthly collections for up to 3 years established seasonal and regional trends in fallout of particulate matter. Fallout was highest in the area of highest rainfall, but correlation of monthly rainfall with fallout was generally not statistically significant. The amount of dust collected was higher under tree foliage than in adjacent open space. Annual accession of atmospheric dust within this urban-rural transect was in the range of 5-10 t km-2 but the occasional severe dust storm could contribute about half the annual rate. These accretions of dust to the landscape, 2.5-5 mm per 1000 years, were about one hundredth of the recommended soil loss tolerance adopted in many studies of soil erosion, and thus unlikely to contribute significantly to models developed for soil loss on that basis. Dust accessions were, however, similar to estimates of rates of soil formation or profile deepening on resistant rocks of 1-5 mm per 1000 years which may be appropriate to conditions in southern Australia. Incorporation of such accessions into existing soils would be difficult to identify yet may provide a significant factor in pedogenesis in the higher rainfall areas. The low rates of soil development in many Australian landscapes, with contribution from both weathering and eolian dust inputs, would encourage the adoption of soil loss tolerances in soil erosion management that are orders of magnitude lower than those commonly accepted.
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Dare, Richard A. y Elizabeth E. Ebert. "Latitudinal variations in the accuracy of model-generated forecasts of precipitation over Australia and south-east Asia". Journal of Southern Hemisphere Earth Systems Science 67, n.º 1 (2017): 46. http://dx.doi.org/10.1071/es17005.
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Forecasts of precipitation produced by global and regional versions of the Bureau of Meteorology’s Australian Community Climate and Earth System Simulator (ACCESS) numerical weather prediction models are compared with Tropical Rainfall Measuring Mission (TRMM) observations for the period January 2011 to March 2014. The area considered covers longitudes 110° to 160°E within 40° latitude of the equator, and includes the Australian continent and part of south-east Asia. Forecast accuracy is assessed using objective measures: equitable threat score (ETS), frequency bias (FB), and the ratio of predicted to observed rain volume (RVR). For the assessment, the TRMM and model datasets are both interpolated to consistent grids defined by spacings of 1° longitude and 1° latitude. Assessments based on three-month seasons show that, in general, the volume of rain predicted by the models is too high, and rainfall is predicted to occur at more locations than observed. Latitudinal variations in values of the ETS reveal marked declines over the equatorial tropics, with minimum values near the equator from December to May and near 10°N from June to November. Differences in the ETS between 24-hour model and persistence forecasts show that the models produce useful predictions of rainfall away from the tropics, poleward of latitudes 5º-15º S and 15º-30º N, depending on the season and model. The 48-hour model predictions are more useful than the 24-hour forecasts, with improvements relative to persistence over most latitudes, although differences are close to zero at low latitudes. Varying the rain threshold used to compute skill metrics shows that the models produce excessive rainfall at low rain rates, generally less than approximately 15 mm day-1, while not enough precipitation is forecast at higher rain rates. Values of the ETS are generally highest at lower rain rates, coinciding with the excessive values of RVR and FB.
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Bano, Sayeeda. "Intra-Industry Trade and Determinant: Evidence for ASEAN-Australia and New Zealand in the Context of AANZFTA". International Journal of Accounting and Financial Reporting 8, n.º 4 (11 de octubre de 2018): 22. http://dx.doi.org/10.5296/ijafr.v8i4.13778.
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This study examines the changing patterns and direction of trade between Association of South- East Asian Nations (ASEAN), Australia and New Zealand in the context of the ASEAN-Australia-New Zealand Free Trade Area/Agreement (AANZFTA) signed in 2010. It investigates the extent of ASEAN’s intra-industry trade with Australia and New Zealand at the 3-digit disaggregated SITC level for the period 1990 to 2014. The study includes an analysis of intra-industry trade indices of trade intensities, the marginal intra-industry trade and the econometric model to identify the determinants of intra-industry trade. The results show that trade in general has increased and intra-industry trade between ASEAN-Australia increased specifically in manufacturing. New Zealand has developed intra-industry trade in both the manufacturing and agriculture sectors. Marginal intra- industry results suggest that some industries transforming from inter-industry trade patterns to intra-industry trade. The results of regression analysis provide some support to the thesis that increase in IIT comes naturally with high average incomes of trade partners and large average market size. As a country’s level of income goes up and its standard of living rise, its citizens tend demand and consume more high quality differentiated products, leading to higher levels of intra-industry trade. This study differs from the existing literature in terms of its scope, methods and policy perspectives. The findings have policy relevance for the ongoing negotiations for a regional comprehensive economic partnership with ASEAN 10, India, China, Japan, Australia and New Zealand. It is reasonable to suggest that intra-industry trade be given due consideration in ongoing regional and bilateral trade negotiations for potential mutual gains from trade for a sustainable regional economic growth.
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Fisher, Daren G., Phillip Wadds y Garner Clancey. "The patchwork of alcohol-free zones and alcohol-prohibited areas in New South Wales (Australia)". Safer Communities 17, n.º 2 (9 de abril de 2018): 94–102. http://dx.doi.org/10.1108/sc-06-2017-0025.
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Purpose Developing policies to curb public alcohol consumption is a priority for governments. In the Australian state of New South Wales (NSW), local governments have introduced alcohol-free zones (AFZs) and alcohol-prohibited areas (APAs) to prohibit the public consumption of alcohol and reduce crime stemming from intoxication. Previous studies, however, argue that these policies are driven by stakeholder desire rather than alcohol-related crime and may result in increased criminal justice contact for vulnerable populations. The purpose of this paper is to estimate the number of AFZs and APAs in NSW and examine the extent to which these policies are connected to the frequency of alcohol-related crime. Design/methodology/approach Examining the 152 local government areas (LGAs) of NSW, the authors analysed whether the implementation of AFZs and APAs were linked to the frequency of liquor offences and assaults using group-based trajectory models. Findings The authors found that AFZs and APAs were often not advertised nor inconsistently implemented both across and within jurisdictions. Group-based trajectory models indicated that AFZs were more common in low liquor offence LGAs than high liquor offences LGAs, but were more frequently implemented in high assault LGAs compared to low assault LGAs. APAs were more common in the lowest crime LGAs compared to those LGAs that experienced higher levels of recorded crime. Originality/value These analyses demonstrate how widespread AFZs and APAs have become and provides evidence that the implementation of is only tenuously linked to the frequency of crime.
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Gray, Jonathan M., Thomas F. A. Bishop y Peter L. Smith. "Digital mapping of pre-European soil carbon stocks and decline since clearing over New South Wales, Australia". Soil Research 54, n.º 1 (2016): 49. http://dx.doi.org/10.1071/sr14307.
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Digital soil models and maps have been developed for pre-European (pre-clearing) levels of soil organic carbon (SOC) over New South Wales, Australia. These provide a useful first estimate of natural, unaltered soil conditions before agricultural development, which are potentially important for many carbon-accounting schemes such as those prescribed by the Intergovernmental Panel on Climate Change, carbon-turnover models such as RothC, and soil-condition monitoring programs. The modelling approach adopted included multiple linear regression and Cubist piecewise linear decision trees. It used 1690 soil profiles from undisturbed or only lightly disturbed native vegetation sites across all of eastern Australia, together with a range of covariates representing key soil-forming factors. The digital soil maps of pre-clearing SOC (% and mass) over New South Wales provide a more sophisticated alternative to currently available, equivalent maps. Independent validation of the SOC mass predictions over the top 30 cm revealed a concordance correlation coefficient of 0.76, which was 13% higher than the currently used map. Total pre-clearing SOC stocks amount to 4.21 Gt in the top 30 cm, which compared with a current stock estimate of 3.68 Gt, suggesting a total SOC loss of ~0.53 Gt over the entire state. The extent of SOC decline in both absolute and relative terms was found to be highly dependent on the climate, parent material and land use regime, reaching a maximum decline of 44.3 t/ha or 50.0% relative loss in cooler (moist) conditions over mafic parent materials under regular cropping use. The models also provide valuable pedological insights into the factors controlling SOC levels under natural conditions.
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Yang, Yi, Yao Dong, Yanhua Chen y Caihong Li. "Intelligent Optimized Combined Model Based on GARCH and SVM for Forecasting Electricity Price of New South Wales, Australia". Abstract and Applied Analysis 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/504064.
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Daily electricity price forecasting plays an essential role in electrical power system operation and planning. The accuracy of forecasting electricity price can ensure that consumers minimize their electricity costs and make producers maximize their profits and avoid volatility. However, the fluctuation of electricity price depends on other commodities and there is a very complicated randomization in its evolution process. Therefore, in recent years, although large number of forecasting methods have been proposed and researched in this domain, it is very difficult to forecast electricity price with only one traditional model for different behaviors of electricity price. In this paper, we propose an optimized combined forecasting model by ant colony optimization algorithm (ACO) based on the generalized autoregressive conditional heteroskedasticity (GARCH) model and support vector machine (SVM) to improve the forecasting accuracy. First, both GARCH model and SVM are developed to forecast short-term electricity price of New South Wales in Australia. Then, ACO algorithm is applied to determine the weight coefficients. Finally, the forecasting errors by three models are analyzed and compared. The experiment results demonstrate that the combined model makes accuracy higher than the single models.
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Kordrostami, Sasan, Mohammad A. Alim, Fazlul Karim y Ataur Rahman. "Regional Flood Frequency Analysis Using An Artificial Neural Network Model". Geosciences 10, n.º 4 (1 de abril de 2020): 127. http://dx.doi.org/10.3390/geosciences10040127.
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This paper presents the results from a study on the application of an artificial neural network (ANN) model for regional flood frequency analysis (RFFA). The study was conducted using stream flow data from 88 gauging stations across New South Wales (NSW) in Australia. Five different models consisting of three to eight predictor variables (i.e., annual rainfall, drainage area, fraction forested area, potential evapotranspiration, rainfall intensity, river slope, shape factor and stream density) were tested. The results show that an ANN model with a higher number of predictor variables does not always improve the performance of RFFA models. For example, the model with three predictor variables performs considerably better than the models using a higher number of predictor variables, except for the one which contains all the eight predictor variables. The model with three predictor variables exhibits smaller median relative error values for 2- and 20-year return periods compared to the model containing eight predictor variables. However, for 5-, 10-, 50- and 100-year return periods, the model with eight predictor variables shows smaller median relative error values. The proposed ANN modelling framework can be adapted to other regions in Australia and abroad.
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Culvenor, R. A., M. R. Norton y J. De Faveri. "Persistence and productivity of phalaris (Phalaris aquatica) germplasm in dry marginal rainfall environments of south-eastern Australia". Crop and Pasture Science 68, n.º 8 (2017): 781. http://dx.doi.org/10.1071/cp17203.
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Perennial grasses have production and environmental benefits in areas of southern Australia typified by the mixed farming zone of southern New South Wales (NSW). The perennial grass phalaris (Phalaris aquatica L.) is widely used in southern Australia; however, it would find more use in the mixed farming zone if its persistence in marginal rainfall areas (450–500 mm average annual rainfall) were improved. We evaluated a range of germplasm (n = 29) including wild accessions, lines bred from these, and existing cultivars for persistence and production at three sites in a summer-dry area of southern NSW with 430–460-mm average annual rainfall. Two sites were used over 4 years and the third site over 5 years. Summer dormancy, maturity time and seedling growth were also assessed. Analysis of genotype × environment interaction employing factor analytic models and accounting for spatial and temporal correlations indicated that changes in persistence occurred mainly over time rather than between sites. Ranking changes occurred in the dry establishment phase of the experiment and during a severe final summer drought, with few changes occurring in the intervening high-rainfall years. Lines that survived the establishment phase best had vigorous seedlings and earlier maturity, whereas those surviving the final summer best were earlier maturing and higher in summer dormancy with high winter-growth activity. Some later maturing lines within the higher summer dormancy group were less persistent. Some accessions from North Africa were the most persistent; also, populations bred from these and other more persistent accessions generally persisted and produced better than cultivars used presently. However, present cultivars were capable of high yield in the higher rainfall years. We suggest that persistence of higher summer dormancy cultivars over very dry years could be improved by selecting for earlier maturity time.
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Zhang, Yang y Samsung Lim. "Drivers of Wildfire Occurrence Patterns in the Inland Riverine Environment of New South Wales, Australia". Forests 10, n.º 6 (24 de junio de 2019): 524. http://dx.doi.org/10.3390/f10060524.
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In the inland riverine environment of Australia, wildfires not only threaten human life and cause economic loss but also make distinctive impacts on the ecosystem (e.g., injuring or killing fire-sensitive wetland species such as the river red gum). Understanding the drivers of wildfire occurrence patterns in this particular environment is vital for fire-risk reduction and ecologically sustainable management. This study investigated patterns and driving factors of wildfire occurrence over the years from 2001 to 2016 and across the New South Wales side of the Riverina bioregion. Descriptive analyses were conducted for fires of different causes and that burned different vegetation types. Logistic regression models were developed by incorporating factors that provide information on weather, climate, fuel, topography and ignition sources. Analyses revealed that most fires occurred in summer, with human-caused fires primarily in spring and summer, and natural fires in summer. Summer was the most fire-prone season in forested wetlands, whereas fires in drylands mostly occurred during spring and summer. Fire probabilities were higher under severe weather conditions, in areas with higher annual rainfall, in forested wetlands and in areas with intermediate inundation frequencies. Special attention needs to be paid to the effects of vegetation type and inundation frequency on fire occurrence. Weather, climate&fuel and ignition sources were comparably important in explaining human-caused fire occurrence, whereas weather was more important than climate&fuel in explaining natural fire occurrence. Understandings obtained from this study can potentially support the planning of fire and forest management, as well as to supplement the relatively scarce knowledge on riverine wildfire occurrence.
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Bradstock, R. A., J. S. Cohn, A. M. Gill, M. Bedward y C. Lucas. "Prediction of the probability of large fires in the Sydney region of south-eastern Australia using fire weather". International Journal of Wildland Fire 18, n.º 8 (2009): 932. http://dx.doi.org/10.1071/wf08133.
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The probability of large-fire (≥1000 ha) ignition days, in the Sydney region, was examined using historical records. Relative influences of the ambient and drought components of the Forest Fire Danger Index (FFDI) on large fire ignition probability were explored using Bayesian logistic regression. The preferred models for two areas (Blue Mountains and Central Coast) were composed of the sum of FFDI (Drought Factor, DF = 1) (ambient component) and DF as predictors. Both drought and ambient weather positively affected the chance of large fire ignitions, with large fires more probable on the Central Coast than in the Blue Mountains. The preferred, additive combination of drought and ambient weather had a marked threshold effect on large-fire ignition and total area burned in both localities. This may be due to a landscape-scale increase in the connectivity of available fuel at high values of the index. Higher probability of large fires on the Central Coast may be due to more subdued terrain or higher population density and ignitions. Climate scenarios for 2050 yielded predictions of a 20–84% increase in potential large-fire ignitions days, using the preferred model.
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McDougall, Keith L. "Evidence for the natural occurrence of treeless grasslands in the Riverina region of south-eastern Australia". Australian Journal of Botany 56, n.º 6 (2008): 461. http://dx.doi.org/10.1071/bt08036.
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Grasslands in the Riverina region of south-eastern Australia have long been thought to be derived from woodland dominated by Acacia pendula A.Cunn. ex G.Don and Atriplex nummularia Lindl. following over-grazing and clearing in the 19th Century. Despite the broad acceptance of this view, there is little evidence for such a universal change having occurred. Phytosociological and historical evidence is presented here, which suggests that, although many of the existing grassland remnants are floristically similar to remnants of A. pendula woodland and are probably derived from woodland, natural treeless grassland also probably occurs in the Riverina. Such grassland is floristically distinct from remnant woodland and generally spatially separate, being prevalent in the southern Riverina. Although the delineation of natural and derived grassland boundaries may now be difficult, grassland vegetation in general is of immense biodiversity significance, containing a large number of highly localised rare or threatened species. A decrease in rainfall during the winter and spring growing season, as predicted by climate-change models, may be detrimental to natural grassland, which is restricted to the higher rainfall portion of the Riverina.
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Linnane, Adrian, David Hobday, Stewart Frusher y Caleb Gardner. "Growth rates of juvenile southern rock lobster (Jasus edwardsii) estimated through a diver-based tag - recapture program". Marine and Freshwater Research 63, n.º 2 (2012): 110. http://dx.doi.org/10.1071/mf11121.
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Despite being one of the most economically important fisheries in south-eastern Australia, growth rates of juvenile southern rock lobster (Jasus edwardsii) have not previously been quantified in the wild. This study utilised a diver-based tag–recapture program to estimate growth rates of individuals between 40–80 mm carapace length (CL) in temperate reef sites across south-eastern Australia. Of the 7064 lobsters tagged and released, 978 (14%) were recaptured with recapture rates of 23, 5 and 7% in the States of Tasmania, South Australia and Victoria respectively. Although individual growth increments were similar between the sexes, differences in annual growth rates were evident at 50 mm CL, with males growing ~1.4 times faster than females. Increased levels of growth in males resulted from a higher moult frequency, which was found to significantly reduce in females as they reached sexual maturity at ~70–80 mm CL. No significant difference was found in growth rates of males or females between the States when all sites within each State were combined. The growth estimates from this work contribute to the understanding of juvenile lobster population dynamics and will improve current fishery models by confirming relationships between early juvenile, pre-recruit abundance and entry to the fishable biomass.
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Taggart, Patrick L., Bronwyn A. Fancourt, Andrew J. Bengsen, David E. Peacock, Patrick Hodgens, John L. Read, Milton M. McAllister y Charles G. B. Caraguel. "Evidence of significantly higher island feral cat abundance compared with the adjacent mainland". Wildlife Research 46, n.º 5 (2019): 378. http://dx.doi.org/10.1071/wr18118.
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Context Feral cats (Felis catus) impact the health and welfare of wildlife, livestock and humans worldwide. They are particularly damaging where they have been introduced into island countries such as Australia and New Zealand, where native prey species evolved without feline predators. Kangaroo Island, in South Australia, is Australia’s third largest island and supports several threatened and endemic species. Cat densities on Kangaroo Island are thought to be greater than those on the adjacent South Australian mainland, based on one cat density estimate on the island that is higher than most estimates from the mainland. The prevalence of cat-borne disease in cats and sheep is also higher on Kangaroo Island than the mainland, suggesting higher cat densities. A recent continental-scale spatial model of cat density predicted that cat density on Kangaroo Island should be about double that of the adjacent mainland. However, although cats are believed to have severe impacts on some native species on the island, other species that are generally considered vulnerable to cat predation have relatively secure populations on the island compared with the mainland. Aims The present study aimed to compare feral cat abundance between Kangaroo Island and the adjacent South Australian mainland using simultaneous standardised methods. Based on previous findings, we predicted that the relative abundance of feral cats on Kangaroo Island would be approximately double that on the South Australian mainland. Methods Standardised camera trap surveys were used to simultaneously estimate the relative abundance of feral cats on Kangaroo Island and the adjacent South Australian mainland. Survey data were analysed using the Royle–Nichols abundance-induced heterogeneity model to estimate feral cat relative abundance at each site. Key results Cat abundance on the island was estimated to be over 10 times greater than that on the adjacent mainland. Conclusions Consistent with predictions, cat abundance on the island was greater than on the adjacent mainland. However, the magnitude of this difference was much greater than expected. Implications The findings show that the actual densities of cats at local sites can vary substantially from predictions generated by continental-scale models. The study also demonstrates the value of estimating abundance or density simultaneously across sites using standardised methods.
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Loveridge, Melanie, Ataur Rahman y Peter Hill. "Applicability of a physically based soil water model (SWMOD) in design flood estimation in eastern Australia". Hydrology Research 48, n.º 6 (28 de diciembre de 2016): 1652–65. http://dx.doi.org/10.2166/nh.2016.118.
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Abstract Event-based rainfall–runoff models are useful tools for hydrologic design. Of the many loss models, the ‘initial loss-continuing loss’ model is widely adopted in practice. Some of the key limitations with these types of loss models include the arbitrary selection of initial moisture (IM) conditions and lack of physically meaningful parameters. This paper investigates the applicability of a physically based soil water balance model (SWMOD) with distributed IM conditions for flood modelling. Four catchments from the east coast of New South Wales, Australia, are modelled. The IM content in SWMOD represents the antecedent moisture condition. A quasi-Monte Carlo simulation framework is adopted, where the IM is stochastically varied according to a lognormal probability distribution. In calibration, it is found that the adopted modelling framework is able to simulate the majority of the observed flood hydrographs with a higher degree of accuracy; however, in a design context, when compared to the results of conventional flood frequency analysis, discrepancies are noted for a range of annual exceedance probabilities. The quasi-Monte Carlo simulation framework proved to be useful in assessing the effect of the IM content on design flood estimates.
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Cullen, B. R., R. J. Eckard y R. P. Rawnsley. "Resistance of pasture production to projected climate changes in south-eastern Australia". Crop and Pasture Science 63, n.º 1 (2012): 77. http://dx.doi.org/10.1071/cp11274.
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Climate change impact analysis relies largely on down-scaling climate projections to develop daily time-step, future climate scenarios for use in agricultural systems models. This process of climate down-scaling is complicated by differences in projections from greenhouse gas emission pathways and, in particular, the wide variation between global climate model outputs. In this study, a sensitivity analysis was used to test the resistance of pasture production to the incremental changes in climate predicted over the next 60 years in southern Australia. Twenty-five future climate scenarios were developed by scaling the historical climate by increments of 0, 1, 2, 3 and 4°C (with corresponding changes to atmospheric carbon dioxide concentrations and relative humidity) and rainfall by +10, 0, –10, –20 and –30%. The resistance of annual and seasonal pasture production to these climatic changes was simulated at six sites in south-eastern Australia. The sites spanned a range of climates from high rainfall, cool temperate in north-west Tasmania to the lower rainfall, temperate environment of Wagga Wagga in southern New South Wales. Local soil and pasture types were simulated at each site using the Sustainable Grazing Systems Pasture model. Little change or higher annual pasture production was simulated at all sites with 1°C warming, but varying responses were observed with further warming. In a pasture containing a C4 native grass at Wagga Wagga, annual pasture production increased with further warming, while production was stable or declined in pasture types based on C3 species in temperate environments. In a cool temperate region pasture production increased with up to 2°C warming. Compared with the historical baseline climate, warmer and drier climate scenarios led to lower pasture production, with summer and autumn growth being most affected, although there was some variation between sites. At all sites winter production was increased under all warming scenarios. Inter-annual variation in pasture production, expressed as the coefficient of variation, increased in the lower rainfall scenarios where production was simulated to decline, suggesting that changing rainfall patterns are likely to affect the variability in pasture production more than increasing temperatures. Together the results indicate that annual pasture production is resistant to climatic changes of up to 2°C warming. The approach used in this study can be used to test the sensitivity of agricultural production to climatic changes; however, it does not incorporate changes in seasonal and extreme climatic events that may also have significant impacts on these systems. Nonetheless, the approach can be used to identify strategies that may increase resilience of agricultural systems to climate change such as the incorporation of C4 species into the pasture base.
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Brown, Geoff W., Andrew F. Bennett y Joanne M. Potts. "Regional faunal decline - reptile occurrence in fragmented rural landscapes of south-eastern Australia". Wildlife Research 35, n.º 1 (2008): 8. http://dx.doi.org/10.1071/wr07010.
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Many species of reptiles are sedentary and depend on ground-layer habitats, suggesting that they may be particularly vulnerable to landscape changes that result in isolation or degradation of native vegetation. We investigated patterns of reptile distribution and abundance in remnant woodland across the Victorian Riverina, south-eastern Australia, a bioregion highly modified (>90%) by clearing for agriculture. Reptiles were intensively surveyed by pitfall trapping and censuses at 60 sites, stratified to sample small (<30 ha) and large (>30 ha) remnants, and linear strips of roadside and streamside vegetation, across the regional environmental gradient. The recorded assemblage of 21 species was characterised by low abundance and patchy distribution of species. Reptiles were not recorded by either survey technique at 22% of sites and at a further 10% only a single individual was detected. More than half (53%) of all records were of two widespread, generalist skink species. Multivariate models showed that the distribution of reptiles is influenced by factors operating at several levels. The environmental gradient exerts a strong influence, with increasing species richness and numbers of individuals from east (moister, higher elevation) to west (drier, lower elevation). Differences existed between types of remnants, with roadside vegetation standing out as important; this probably reflects greater structural heterogeneity of ground and shrub strata than in remnants subject to grazing by stock. Although comparative historical data are lacking, we argue that there has been a region-wide decline in the status of reptiles in the Victorian Riverina involving: (1) overall population decline commensurate with loss of >90% of native vegetation; (2) disproportionate decline of grassy dry woodlands and their fauna (cf. floodplains); and (3) changes to populations and assemblages in surviving remnants due to effects of land-use on reptile habitats. Many species now occur as disjunct populations, vulnerable to changing land-use. The status of reptiles in rural Australia warrants greater attention than has been given to date. Effective conservation of this component of the biota requires better understanding of the population dynamics, habitat use and dispersal capacity of species; and a commitment to landscape restoration coupled with effective ecological monitoring.
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Turner, Neil C., Nicholas Molyneux, Sen Yang, You-Cai Xiong y Kadambot H. M. Siddique. "Climate change in south-west Australia and north-west China: challenges and opportunities for crop production". Crop and Pasture Science 62, n.º 6 (2011): 445. http://dx.doi.org/10.1071/cp10372.
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Predictions from climate simulation models suggest that by 2050 mean temperatures on the Loess Plateau of China will increase by 2.5 to 3.75°C, while those in the cropping region of south-west Australia will increase by 1.25 to 1.75°C. By 2050, rainfall is not expected to change on the Loess Plateau of China, while in south-west Australia rainfall is predicted to decrease by 20 to 60 mm. The frequency of heat waves and dry spells is predicted to increase in both regions. The implications of rising temperatures are an acceleration of crop phenology and a reduction in crop yields, greater risk of reproductive failure from extreme temperatures, and greater risk of crop failure. The reduction in yield from increased phenological development can be countered by selecting longer-season cultivars and taking advantage of warmer minimum temperatures and reduced frost risk to plant earlier than with current temperatures. Breeding for tolerance of extreme temperatures will be necessary to counter the increased frequency of extreme temperatures, while a greater emphasis on breeding for increased drought resistance and precipitation-use efficiency will lessen the impact of reduced rainfall. Management options likely to be adopted in south-west Australia include the introduction of drought-tolerant perennial fodder species and shifting cropping to higher-rainfall areas. On the Loess Plateau of China, food security is paramount so that an increased area of heat-tolerant and high-yielding maize, mulching with residues and plastic film, better weed and pest control and strategic use of supplemental irrigation to improve rainfall-use efficiency are likely to be adopted.
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Roshier, David A., Felicity L. Hotellier, Andrew Carter, Leah Kemp, Joanne Potts, Matt W. Hayward y Sarah M. Legge. "Long-term benefits and short-term costs: small vertebrate responses to predator exclusion and native mammal reintroductions in south-western New South Wales, Australia". Wildlife Research 47, n.º 8 (2020): 570. http://dx.doi.org/10.1071/wr19153.
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Abstract ContextThe success of conservation fences at protecting reintroduced populations of threatened mammals from introduced predators has prompted an increase in the number and extent of fenced exclosures. Excluding introduced species from within conservation fences could also benefit components of insitu faunal assemblages that are prey for introduced predators, such as reptiles and small mammals. Conversely, reintroduced mammals may compete with smaller mammals and reptiles for resources, or even prey on them. AimsIn a 10-year study from 2008, we examine how small terrestrial vertebrates respond to the exclusion of introduced predators, the feral cat (Felis catus) and red fox (Vulpes Vulpes), introduced herbivores and the reintroduction of regionally extinct mammal species. MethodsDifferences in the yearly relative abundance of reptiles and mammals according to habitat type and whether sites were fenced or not, were tested using multivariate generalised linear models. Next, we calculated univariate P-values to identify individual species that showed significant relationships, positive and negative, with any of the explanatory variables. Key resultsTotal captures of reptiles were lower inside the conservation fence in all years, whereas total captures of small mammals were markedly higher inside the fenced area, notably in dasyurids. ConclusionOur results showed that conservation fences can deliver benefits for some fauna (but not all) beyond facilitating the reintroduction of highly threatened mammals. ImplicationsOur results demonstrated the consequential impacts of introduced predators on the Australian small mammal fauna, and showed that predator-exclusion fences can be an effective conservation intervention for this guild.
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Su, Chun-Hsu, Nathan Eizenberg, Peter Steinle, Dörte Jakob, Paul Fox-Hughes, Christopher J. White, Susan Rennie, Charmaine Franklin, Imtiaz Dharssi y Hongyan Zhu. "BARRA v1.0: the Bureau of Meteorology Atmospheric high-resolution Regional Reanalysis for Australia". Geoscientific Model Development 12, n.º 5 (24 de mayo de 2019): 2049–68. http://dx.doi.org/10.5194/gmd-12-2049-2019.
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Abstract. The Bureau of Meteorology Atmospheric high-resolution Regional Reanalysis for Australia (BARRA) is the first atmospheric regional reanalysis over a large region covering Australia, New Zealand, and Southeast Asia. The production of the reanalysis with approximately 12 km horizontal resolution – BARRA-R – is well underway with completion expected in 2019. This paper describes the numerical weather forecast model, the data assimilation methods, the forcing and observational data used to produce BARRA-R, and analyses results from the 2003–2016 reanalysis. BARRA-R provides a realistic depiction of the meteorology at and near the surface over land as diagnosed by temperature, wind speed, surface pressure, and precipitation. Comparing against the global reanalyses ERA-Interim and MERRA-2, BARRA-R scores lower root mean square errors when evaluated against (point-scale) 2 m temperature, 10 m wind speed, and surface pressure observations. It also shows reduced biases in daily 2 m temperature maximum and minimum at 5 km resolution and a higher frequency of very heavy precipitation days at 5 and 25 km resolution when compared to gridded satellite and gauge analyses. Some issues with BARRA-R are also identified: biases in 10 m wind, lower precipitation than observed over the tropical oceans, and higher precipitation over regions with higher elevations in south Asia and New Zealand. Some of these issues could be improved through dynamical downscaling of BARRA-R fields using convective-scale (<2 km) models.
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Speer, MS, LM Leslie, JR Colquhoun y E. Mitchell. "The Sydney Australia Wildfires of January 1994 - Meteorological Conditions and High Resolution Numerical Modeling Experiments". International Journal of Wildland Fire 6, n.º 3 (1996): 145. http://dx.doi.org/10.1071/wf9960145.
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Southeastern Australia is particularly vulnerable to wildfires during the spring and summer months, and the threat of devastation is present most years. In January 1994, the most populous city in Australia, Sydney, was ringed by wildfires, some of which penetrated well into suburban areas and there were many other serious fires in coastal areas of New South Wales (NSW). In recent years much research activity in Australia has focussed on the development of high resolution limited area models, for eventual operational prediction of meteorological conditions associated with high levels of wildfire risk. In this study, the period January 7-8, 1994 was chosen for detailed examination, as it was the most critical period during late December 1993/early January 1994 for the greater Sydney area. Routine forecast guidance from the Australian Bureau of Meteorology's operational numerical weather prediction (NWP) models was very useful in that both the medium and short range models predicted synoptic patterns suggesting extreme fire weather conditions up to several days in advance. However, vital information of a detailed nature was lacking. A new high resolution model was run at the operational resolution of 150 km and the much higher resolutions of 25 km and 5 km. The new model showed statistically significant greater skill in predicting details of wind, relative humidity and temperature patterns both near the surface and above the boundary layer. It also produced skilful predictions of the Forest Fire Danger Index.
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Peisley, Rebecca K., Manu E. Saunders y Gary W. Luck. "Cost-benefit trade-offs of bird activity in apple orchards". PeerJ 4 (30 de junio de 2016): e2179. http://dx.doi.org/10.7717/peerj.2179.
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Birds active in apple orchards in south–eastern Australia can contribute positively (e.g., control crop pests) or negatively (e.g., crop damage) to crop yields. Our study is the first to identify net outcomes of these activities, using six apple orchards, varying in management intensity, in south–eastern Australia as a study system. We also conducted a predation experiment using real and artificial codling moth (Cydia pomonella) larvae (a major pest in apple crops). We found that: (1) excluding birds from branches of apple trees resulted in an average of 12.8% more apples damaged by insects; (2) bird damage to apples was low (1.9% of apples); and (3) when trading off the potential benefits (biological control) with costs (bird damage to apples), birds provided an overall net benefit to orchard growers. We found that predation of real codling moth larvae was higher than for plasticine larvae, suggesting that plasticine prey models are not useful for inferring actual predation levels. Our study shows how complex ecological interactions between birds and invertebrates affect crop yield in apples, and provides practical strategies for improving the sustainability of orchard systems.
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Pitman, A. J. y S. E. Perkins. "Regional Projections of Future Seasonal and Annual Changes in Rainfall and Temperature over Australia Based on Skill-Selected AR4 Models". Earth Interactions 12, n.º 12 (1 de agosto de 2008): 1–50. http://dx.doi.org/10.1175/2008ei260.1.
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Abstract Daily data from climate models submitted to the Fourth Assessment of the Intergovernmental Panel on Climate Change are compared with daily data from observations over Australia by measuring the overlap of the probability density functions (PDFs). The capacity of these models to simulate maximum temperature, minimum temperature, and precipitation is assessed. The resulting skill score is then used to exclude models with relatively poor skill region by region over Australia. The remaining sample of coupled climate models is then used to determine the seasonal changes in these three variables under a high- (A2) and low- (B1) emission scenario for 2050 and 2100. The authors demonstrate that some projected phenomena, such as the projected drying over southwest Western Australia, are robust and not caused by the inclusion of some weak models in earlier assessments. Some other results, such as the projected change in the monsoon, are more consistent among the good climate models. Consistent with earlier work, a consistent pattern of mean warming is identified in the projections. The amount of warming in the 99.7th percentile is not dramatically higher than the warming in the mean. However, while the mean warming is generally least in the south, the amount of warming in the 99.7th percentile is substantially higher along the southern coast of Australia. This is due to a coupling of the temperature response with reduced rainfall, which causes drying and allows extreme maximum temperatures to increase dramatically. The authors show that, in general, the amount of rainfall is projected to change relatively little, but the frequency of rainfall decreases and the intensity of rainfall at the upper tail of the distribution increases. However, the scale of the increase in extreme rainfall is not large on the time scales analyzed here. The range in projected temperature changes among those climate models with skill in simulating the observations is at least twice as large for the 99.7th/0.3rd percentiles as for the mean. For rainfall, the range among the good models is of order 10 times greater in the 99.7th percentile than in the mean. Since the impact of changes in extremes is increasingly recognized as societally important, this result strongly limits the use of climate model data to explore sectors that are vulnerable to extremes. This suggests an evaluation strategy that focuses on model capacity to simulate whole PDFs since capacity to simulate the mean is a necessary but insufficient criterion for determining a model’s value for future projection.
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Guyot, Adrien, Jayaram Pudashine, Alain Protat, Remko Uijlenhoet, Valentijn R. N. Pauwels, Alan Seed y Jeffrey P. Walker. "Effect of disdrometer type on rain drop size distribution characterisation: a new dataset for south-eastern Australia". Hydrology and Earth System Sciences 23, n.º 11 (19 de noviembre de 2019): 4737–61. http://dx.doi.org/10.5194/hess-23-4737-2019.
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Abstract. Knowledge of the full rainfall drop size distribution (DSD) is critical for characterising liquid water precipitation for applications such as rainfall retrievals using electromagnetic signals and atmospheric model parameterisation. Southern Hemisphere temperate latitudes have a lack of DSD observations and their integrated variables. Laser-based disdrometers rely on the attenuation of a beam by falling particles and are currently the most commonly used type of instrument to observe the DSD. However, there remain questions on the accuracy and variability in the DSDs measured by co-located instruments, whether identical models, different models or from different manufacturers. In this study, raw and processed DSD observations obtained from two of the most commonly deployed laser disdrometers, namely the Parsivel1 from OTT and the Laser Precipitation Monitor (LPM) from Thies Clima, are analysed and compared. Four co-located instruments of each type were deployed over 3 years from 2014 to 2017 in the proximity of Melbourne, a region prone to coastal rainfall in south-eastern Australia. This dataset includes a total of approximately 1.5 million recorded minutes, including over 40 000 min of quality rainfall data common to all instruments, equivalent to a cumulative amount of rainfall ranging from 1093 to 1244 mm (depending on the instrument records) for a total of 318 rainfall events. Most of the events lasted between 20 and 40 min for rainfall amounts of 0.12 to 26.0 mm. The co-located LPM sensors show very similar observations, while the co-located Parsivel1 systems show significantly different results. The LPM recorded 1 to 2 orders of magnitude more smaller droplets for drop diameters below 0.6 mm compared to the Parsivel1, with differences increasing at higher rainfall rates. The LPM integrated variables showed systematically lower values compared to the Parsivel1. Radar reflectivity–rainfall rate (ZH–R) relationships and resulting potential errors are also presented. Specific ZH–R relations for drizzle and convective rainfall are also derived based on DSD collected for each instrument type. Variability of the DSD as observed by co-located instruments of the same manufacturer had little impact on the estimated ZH–R relationships for stratiform rainfall, but differs when considering convective rainfall relations or ZH–R relations fitted to all available data. Conversely, disdrometer-derived ZH–R relations as compared to the Marshall–Palmer relation ZH=200R1.6 led to a bias in rainfall rates for reflectivities of 50 dBZ of up to 21.6 mm h−1. This study provides an open-source high-resolution dataset of co-located DSD to further explore sampling effects at the micro scale, along with rainfall microstructure.
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Zeng, Xubin, Mike Barlage, Chris Castro y Kelly Fling. "Comparison of Land–Precipitation Coupling Strength Using Observations and Models". Journal of Hydrometeorology 11, n.º 4 (1 de agosto de 2010): 979–94. http://dx.doi.org/10.1175/2010jhm1226.1.
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Abstract Numerous studies have attempted to address the land–precipitation coupling, but scientists’ understanding remains limited and discrepancies still exist from different studies. A new parameter Γ is proposed here to estimate the land–precipitation coupling strength based on the ratio of the covariance between monthly or seasonal precipitation and evaporation anomalies (from their climatological means) over the variance of precipitation anomalies. The Γ value is easy to compute and insensitive to the horizontal scales used; however, it does not provide causality. A relatively high Γ is a necessary—but not sufficient—condition for a relatively strong land–precipitation coupling. A computation of Γ values using two global reanalyses (ECMWF and NCEP), one regional reanalysis [North American Regional Reanalysis (NARR)], and observed precipitation along with Variable Infiltration Capacity (VIC)-derived evaporation data indicates that the land–precipitation coupling is stronger in summer and weaker in winter. The strongest coupling (i.e., hot spots) occurs over the western and central parts of North America, part of the Eurasia midlatitude, and Sahel in boreal summer and over most of Australia, Argentina, and South Africa in austral summer. The Community Climate System Model, version 3 (CCSM3) shows much higher Γ values, consistent with the strong coupling shown by its atmosphere–land coupled components in previous studies. Its overall spatial pattern of Γ values is not affected much over most regions by the doubling of CO2 in CCSM3. The Γ values from the Regional Atmospheric Modeling System (RAMS) are more realistic than those from CCSM3; however, they are still higher than those from observations over North America.
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Chambers, Mark S., Leesa A. Sidhu y Ben O’Neill. "Southern bluefin tuna (Thunnus maccoyii) shed tags at a higher rate in tuna farms than in the open ocean — two-stage tag retention models". Canadian Journal of Fisheries and Aquatic Sciences 71, n.º 8 (agosto de 2014): 1220–28. http://dx.doi.org/10.1139/cjfas-2013-0325.
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Tag shedding rates are estimated for southern bluefin tuna (SBT, Thunnus maccoyii) from double-tagging data arising from two tagging studies run in the 1990s and 2000s. Since the early 1990s, a high proportion of SBT tag recoveries has been sourced from juveniles captured by purse seine vessels in the Great Australian Bight and transferred to tuna farms off Port Lincoln in the state of South Australia. When tags have been shed by wild-caught SBT fattened in tuna farms, it is generally not known if the tags were shed in the open ocean before purse seine capture or after purse seine capture while the fish were on farm. Using a Bayesian approach, we fit separate tag retention curves for time in the ocean and time on farms as Weibull distribution reliability functions. The study suggests SBT shed tags at a much higher rate in on-farm enclosures than in the open ocean. Biofouling on tags in tuna farms may contribute to higher tag shedding rates.
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Yu, B. y C. J. Rosewell. "Evaluation of WEPP for runoff and soil loss prediction at Gunnedah, NSW, Australia". Soil Research 39, n.º 5 (2001): 1131. http://dx.doi.org/10.1071/sr00091.
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It is important to use historical data to test physically based runoff and soil erosion prediction models as well as the method to estimate model parameters. WEPP (Water Erosion Prediction Project) was validated for bare fallow and annual wheat treatments at Gunnedah, New South Wales, Australia. Wheat stubble was either burned or mulched. Climate, soil, management, and runoff and soil loss data were collected for the period 1980–87 for 3 bare fallow plots, and 1950–74 for 10 annual wheat plots. Three slope lengths from 21 to 62 m were established for the treatment with stubble burned. Slope steepness varied from 8% to 9% at the site. Effective saturated hydraulic conductivity and soil erodibility parameters were estimated from measured soil properties. No further calibration of these parameters was attempted in order to assess the true potential of the model for runoff and soil loss predictions. WEPP worked well for the bare fallow plots with prediction efficiency of 0.97 for event runoff and soil losses. WEPP generally over-predicted the runoff, and consequently, the soil loss for annual wheat treatments for the site. WEPP was able to predict the effect of slope length on sediment concentration and soil loss for the site. CLIGEN, which provides the continuous climate input to WEPP, was found to produce adequately the mean daily rainfall, but produced higher than expected peak rainfall intensity, resulting in higher runoff and soil loss for all treatments.
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Pirie, Adam, Balwant Singh y Kamrunnahar Islam. "Ultra-violet, visible, near-infrared, and mid-infrared diffuse reflectance spectroscopic techniques to predict several soil properties". Soil Research 43, n.º 6 (2005): 713. http://dx.doi.org/10.1071/sr04182.
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Reflectance spectroscopy techniques in the ultraviolet, visible, near-infrared and mid-infrared regions are alternatives for many traditional laboratory methods for measuring soil properties. However, debate exists over whether the near-infrared (700–2500 nm) or the mid-infrared (MIR, 2500–25000 nm) region of the electromagnetic spectrum is more useful for predicting soil properties. Therefore, the aim of this study was to compare UV-VIS-NIR and MIR spectroscopic techniques to predict several soil properties. A total of 415 surface and subsurface soil samples were collected from widely spread locations within New South Wales and south-eastern Queensland of Australia to model the proposed hypothesis. Principal component regression analysis (PCR) was used to develop calibration and validation models from soil spectra and reference laboratory values. The models developed using MIR spectra achieved higher prediction accuracy (regression coefficient, r2 = 0.62–0.85) for pH, organic carbon, clay, sand, CEC, and exchangeable Ca and Mg than that obtained by UV-VIS-NIR spectra (r2 = 0.28–0.76). PCR models were also developed for the combined spectral regions (UV-VIS-NIR+MIR). The models developed using combined spectra were also found to predict pH, organic carbon, clay, sand, CEC, and exchangeable Ca and Mg with acceptable accuracy (r2 = 0.59–0.79). The results of this study indicate that MIR spectra are better than UV-VIS-NIR spectra for estimation of common soil properties.
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Falster, Michael O., Alastair H. Leyland y Louisa R. Jorm. "Do hospitals influence geographic variation in admission for preventable hospitalisation? A data linkage study in New South Wales, Australia". BMJ Open 9, n.º 2 (febrero de 2019): e027639. http://dx.doi.org/10.1136/bmjopen-2018-027639.
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ObjectivePreventable hospitalisations are used internationally as a performance indicator for primary care, but the influence of other health system factors remains poorly understood. This study investigated between-hospital variation in rates of preventable hospitalisation.SettingLinked health survey and hospital admissions data for a cohort study of 266 826 people aged over 45 years in the state of New South Wales, Australia.MethodBetween-hospital variation in preventable hospitalisation was quantified using cross-classified multiple-membership multilevel Poisson models, adjusted for personal sociodemographic, health and area-level contextual characteristics. Variation was also explored for two conditions unlikely to be influenced by discretionary admission practice: emergency admissions for acute myocardial infarction (AMI) and hip fracture.ResultsWe found significant between-hospital variation in adjusted rates of preventable hospitalisation, with hospitals varying on average 26% from the state mean. Patients served more by community and multipurpose facilities (smaller facilities primarily in rural areas) had higher rates of preventable hospitalisation. Community hospitals had the greatest between-hospital variation, and included the facilities with the highest rates of preventable hospitalisation. There was comparatively little between-hospital variation in rates of admission for AMI and hip fracture.ConclusionsGeographic variation in preventable hospitalisation is determined in part by hospitals, reflecting different roles played by community and multipurpose facilities, compared with major and principal referral hospitals, within the community. Care should be taken when interpreting the indicator simply as a performance measure for primary care.
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Hagemann, S., C. Chen, D. B. Clark, S. Folwell, S. N. Gosling, I. Haddeland, N. Hanasaki et al. "Climate change impact on available water resources obtained using multiple global climate and hydrology models". Earth System Dynamics Discussions 3, n.º 2 (4 de diciembre de 2012): 1321–45. http://dx.doi.org/10.5194/esdd-3-1321-2012.
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Abstract. Climate change is expected to alter the hydrological cycle resulting in large-scale impacts on water availability. However, future climate change impact assessments are highly uncertain. For the first time, multiple global climate (three) and hydrological models (eight) were used to systematically assess the hydrological response to climate change and project the future state of global water resources. The results show a large spread in projected changes in water resources within the climate–hydrology modelling chain for some regions. They clearly demonstrate that climate models are not the only source of uncertainty for hydrological change. But there are also areas showing a robust change signal, such as at high latitudes and in some mid-latitude regions, where the models agree on the sign of projected hydrological changes, indicative of higher confidence. In many catchments an increase of available water resources is expected but there are some severe decreases in central and Southern Europe, the Middle East, the Mississippi river basin, Southern Africa, Southern China and south eastern Australia.
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Dawes, W., R. Ali, S. Varma, I. Emelyanova, G. Hodgson y D. McFarlane. "Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia". Hydrology and Earth System Sciences 16, n.º 8 (14 de agosto de 2012): 2709–22. http://dx.doi.org/10.5194/hess-16-2709-2012.
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Abstract. The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south-west Western Australia, provides approximately 60 percent of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15 percent. There is expected to be a reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia. Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A vertical flux manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on climate, land cover type (e.g. native trees, plantation, cropping, urban, wetland), soil type, and taking into account the groundwater depth. In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In areas with land-use change, recharge rates have increased. Where rainfall has declined sufficiently, recharge rates are decreasing, and where compensating factors combine, there is little change to recharge. In the southwestern part of the study area, the patterns of groundwater recharge are dictated primarily by soil, geology and land cover. In the sand-dominated areas, there is little response to future climate change, because groundwater levels are shallow and much rainfall is rejected recharge. Where the combination of native vegetation and clayey surface soils restricts possible infiltration, recharge rates are very sensitive to reductions in rainfall. In the northern part of the study area, both climate and land cover strongly influence recharge rates. Recharge under native vegetation is minimal and is relatively higher where grazing and pasture systems have been introduced after clearing of native vegetation. In some areas, the recharge values can be reduced to almost zero, even under dryland agriculture, if the future climate becomes very dry.
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Usher, Kim, Navjot Bhullar, David Sibbritt, Suruchi Sue Anubha Amarasena, Wenbo Peng, Joanne Durkin, Reakeeta Smallwood et al. "Influence of COVID-19 on the preventive health behaviours of indigenous peoples of Australia residing in New South Wales: a mixed-method study protocol". BMJ Open 11, n.º 9 (septiembre de 2021): e047404. http://dx.doi.org/10.1136/bmjopen-2020-047404.
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IntroductionChronic conditions impact indigenous peoples of Australia at a much higher rate than non-indigenous Australians. Attendance at the Medicare Benefits Scheme (MBS) supported indigenous health checks are crucial to improve prevention and management of chronic health conditions. However, in conjunction with lifestyle and environmental factors, attendance rates at primary healthcare services for screening and treatment have fallen in Australia during the COVID-19 pandemic. This study aims to explore the influence of the COVID-19 pandemic on preventive health behaviours of indigenous Australians and the associated barriers to, and enablers of, engagement with health services to formulate a targeted intervention strategy.Methods and analysisA concurrent mixed-methods study (comprising quantitative and qualitative data collection methods) will be employed. Descriptive analysis of MBS data about the characteristics of indigenous peoples of Australia claiming health assessment services will be performed. Generalised estimating equation regression models will be used to examine the use of health assessment services over time. Qualitative interviews informed by indigenous research methods will be conducted. Interviews will investigate barriers to, and enablers of, engagement with health services. Thematic approach guided by the principles of indigenist praxis, storytelling and collaborative research will be used to analyse the interview data. The project commenced in July 2020 and will be completed by July 2022.Ethics and disseminationThe project received ethics approval from the Aboriginal Health and Medical Research Council of New South Wales and the University of New England Human Research Ethics Committee. Findings will be disseminated via peer-reviewed journal articles, conferences, government and relevant stakeholder reports, and infographics.
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Christina, Mathias, Fawziah Limbada y Anne Atlan. "Climatic niche shift of an invasive shrub (Ulex europaeus): a global scale comparison in native and introduced regions". Journal of Plant Ecology 13, n.º 1 (16 de agosto de 2019): 42–50. http://dx.doi.org/10.1093/jpe/rtz041.
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Abstract Aims Invasive species, which recently expanded, may help understand how climatic niche can shift at the time scale of the current global change. Here, we address the climatic niche shift of an invasive shrub (common gorse, Ulex europaeus) at the world and regional scales to assess how it could contribute to increasing invasibility. Methods Based on a 28 187 occurrences database, we used a combination of 9 species distribution models (SDM) to assess regional climatic niche from both the native range (Western Europe) and the introduced range in different parts of the world (North-West America, South America, North Europe, Australia and New Zealand). Important Findings Despite being restricted to annual mean temperature between 4°C and 22°C, as well as annual precipitation higher than 300 mm/year, the range of bioclimatic conditions suitable for gorse was very large. Based on a native versus introduced SDM comparison, we highlighted a niche expansion in North-West America, South America and to a lesser degree in Australia, while a niche displacement was assessed in North Europe. These niche changes induced an increase in potential occupied areas by gorse by 49, 111, 202 and 283% in Australia, North Europe, North-West America and South America, respectively. On the contrary, we found no evidence of niche change in New Zealand, which presents similar climatic condition to the native environment (Western Europe). This study highlights how niche expansion and displacement of gorse might increase invasibility at regional scale. The change in gorse niche toward new climatic conditions may result from adaptive plasticity or genetic evolution and may explain why it has such a high level of invasibility. Taking into account the possibility of a niche shift is crucial to improve invasive plants management and control.
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McAlpine, Janelle M., Daniel R. McKeating, Lisa Vincze, Jessica J. Vanderlelie y Anthony V. Perkins. "Essential Mineral Intake During Pregnancy and Its Association With Maternal Health and Birth Outcomes in South East Queensland, Australia". Nutrition and Metabolic Insights 12 (enero de 2019): 117863881987944. http://dx.doi.org/10.1177/1178638819879444.
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Micronutrient supplements are often recommended during pregnancy, yet their role and necessity remain poorly understood in the Australian population. This study aimed to determine the essential mineral intake of a population of pregnant women in South East Queensland and investigate the effects of supplements on their micronutrient status and birth outcomes. Women completing the Oral Glucose Tolerance Test at two South East Queensland hospitals between 180 and 210 days gestation provided fasting blood samples and dietary data using the Maternal Outcomes and Nutrition Tool (n = 127). Birth outcomes were sourced from medical records. Serum elemental profiles were determined by inductively coupled plasma mass spectrometry (ICP-MS) analysis. Intake of 8 essential minerals was compared with Australian dietary recommendations; matched serum mineral levels were compared with the current Queensland pregnancy reference ranges. Data were examined using cross-sectional cohort design and independent sample t-tests. Supplement use had no significant influence on serum values of trace elements or the incidence of hypertensive disorders, gestational diabetes, preterm birth or infant birthweight. Dietary selenium, zinc and iodine were significantly higher in women birthing beyond 41 completed weeks; selenium ( P = .026) and zinc ( P = .034) both made unique contributions to the regression models when controlling for confounders. Women exhibited adequate to excessive serum micronutrient levels compared with pregnancy reference ranges, a finding consistent with dietary intake calculations. Data suggest that excessive essential mineral intake contributed to prolonged pregnancy in this cohort, supporting previous studies in this population. Further research is required to determine individual needs and eliminate the potential for harm before recommending pregnancy supplements.
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Islam, Farhana y Monzur Alam Imteaz. "Use of Teleconnections to Predict Western Australian Seasonal Rainfall Using ARIMAX Model". Hydrology 7, n.º 3 (5 de agosto de 2020): 52. http://dx.doi.org/10.3390/hydrology7030052.
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Increased demand for engineering propositions to forecast rainfall events in an area or region has resulted in developing different rainfall prediction models. Interestingly, rainfall is a very complicated natural system that requires consideration of various attributes. However, regardless of the predictability performance, easy to use models have always been welcomed over the complex and ambiguous alternatives. This study presents the development of Auto–Regressive Integrated Moving Average models with exogenous input (ARIMAX) to forecast autumn rainfall in the South West Division (SWD) of Western Australia (WA). Climate drivers such as Indian Ocean Dipole (IOD) and El Nino Southern Oscillation (ENSO) were used as predictors. Eight rainfall stations with 100 years of continuous data from two coastal regions (south coast and north coast) were selected. In the south coast region, Albany (0,1,1) with exogenous input DMIOct–Nino3Nov, and Northampton (0,1,1) with exogenous input DMIJan–Nino3Nov were able to forecast autumn rainfall 4 months and 2 months in advance, respectively. Statistical performance of the ARIMAX model was compared with the multiple linear regression (MLR) model, where for calibration and validation periods, the ARIMAX model showed significantly higher correlations (0.60 and 0.80, respectively), compared to the MLR model (0.44 and 0.49, respectively). It was evident that the ARIMAX model can predict rainfall up to 4 months in advance, while the MLR has shown strict limitation of prediction up to 1 month in advance. For WA, the developed ARIMAX model can help to overcome the difficulty in seasonal rainfall prediction as well as its application can make an invaluable contribution to stakeholders’ economic preparedness plans.
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Davy, M. C. y T. B. Koen. "Variations in soil organic carbon for two soil types and six land uses in the Murray Catchment, New South Wales, Australia". Soil Research 51, n.º 8 (2013): 631. http://dx.doi.org/10.1071/sr12353.
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The aim of this study was to investigate variations in soil organic carbon (SOC) for two soil types and six common land uses in the New South Wales Murray Catchment and to explore the factors influencing those variations. Samples were collected from 100 sites on duplex soils (Ustalfs) of the Slopes region, and 100 sites on red-brown earths (Xeralfs) of the Plains region. Stocks of SOC (0–30 cm) across the study area ranged between 22.3 and 86.0 t ha–1, with means (± s.e.) of 42.0 ± 1.3 and 37.9 ± 0.8 t ha–1 for the Slopes and Plains regions, respectively. Higher SOC stocks were present in pasture-dominated land uses compared with mixed cropping in the Slopes region, with particularly high stocks found in pastures at positions on a slope of 7–10%. No significant differences in SOC stocks were identified between land-use groups (pastures or cropping) in the Plains region (<500-mm rainfall zone). Significant correlations were found between SOC and a range of climatic, topographical, and soil physico-chemical variables at both the catchment and sub-regional scale. Soil physico-chemical and topographical factors play an important role in explaining SOC variation and should be incorporated into models that aim to predict SOC sequestration across agricultural landscapes.
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Kirkegaard, J. A., J. M. Lilley, R. D. Brill, S. J. Sprague, N. A. Fettell y G. C. Pengilley. "Re-evaluating sowing time of spring canola (Brassica napus L.) in south-eastern Australia—how early is too early?" Crop and Pasture Science 67, n.º 4 (2016): 381. http://dx.doi.org/10.1071/cp15282.
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Optimising the sowing date of canola (Brassica napus L.) in specific environments is an important determinant of yield worldwide. In eastern Australia, late April to early May has traditionally been considered the optimum sowing window for spring canola, with significant reduction in yield and oil in later sown crops. Recent and projected changes in climate, new vigorous hybrids, and improved fallow management and seeding equipment have stimulated a re-evaluation of early-April sowing to capture physiological advantages of greater biomass production and earlier flowering under contemporary conditions. Early–mid-April sowing generated the highest or equal highest yield and oil content in eight of nine field experiments conducted from 2002 to 2012 in south-eastern Australia. Declines in seed yield (–6.0% to –6.5%), oil content (–0.5% to –1.5%) and water-use efficiency (–3.8% to –5.5%) per week delay in sowing after early April reflected levels reported in previous studies with sowings from late April. Interactions with cultivar phenology were evident at some sites depending on seasonal conditions. There was no consistent difference in performance between hybrid and non-hybrid cultivars at the earliest sowing dates. Despite low temperatures thought to damage early pods at some sites (<−2°C), frost damage did not significantly compromise the yield of the early-sown crops, presumably because of greater impact of heat and water-stress in the later sown crops. A validated APSIM-Canola simulation study using 50 years of weather data at selected sites predicted highest potential yields from early-April sowing. However, the application of a frost-heat sensitivity index to account for impacts of temperature stress during the reproductive phase predicted lower yields and higher yield variability from early-April sowing. The frost–heat-limited yields predicted optimum sowing times of mid-April at southern sites, and late April to early May at the northern sites with lower median yield and higher yield variability in crops sown in early April. The experimental and simulation data are potentially compatible given that the experiments occurred during the decade of the Millennium drought in south-eastern Australia (2002–10), with dry and hot spring conditions favouring earlier sowing. However, the study reveals the need for more accurate and validated prediction of the frost and heat impacts on field-grown canola if simulation models are to provide more accurate prediction of attainable yield as new combinations of cultivar and sowing dates are explored.
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Trahar, Sheila. "Editorial". Learning and Teaching 8, n.º 1 (1 de marzo de 2015): 1–4. http://dx.doi.org/10.3167/latiss.2015.080101.
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Transnational higher education (TNHE) is a term used for a range of international activities but most commonly it describes programmes where students are located in a different country from the degree-awarding institution. Partnership models include distance learning, dual degrees, franchising and ‘flying faculty’, where academics from the degree-awarding institution fly to another country to teach a programme there. TNHE partnerships are established between institutions for several reasons, not least because of the increase in marketisation of higher education together with the reduction in public funding in many contexts. Interrogating how ‘commercial imperatives nest with academic integrity’ (Sidhu and Christie 2014: 2) is important as many TNHE partnerships are established between ‘Northern’ universities, in particular from Anglo-Celtic countries such as Australia, the U.K. and the U.S.A., and those from the ‘South’ or the ‘East’. Care needs to be taken, therefore, in exercising academic integrity in learning, teaching and assessment in contexts with different academic traditions from those of the degree-awarding institution.
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Theimer, Tad C. "Intraspecific variation in seed size affects scatterhoarding behaviour of an Australian tropical rain-forest rodent". Journal of Tropical Ecology 19, n.º 1 (enero de 2003): 95–98. http://dx.doi.org/10.1017/s0266467403003110.
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Vertebrate seed dispersers could impact the evolution of seed size or alter the pattern of seedling recruitment if they responded differently to seeds of varying size (Jordano 1995). For example, models of seed caching by birds and mammals predict that seeds of higher nutritive value should be placed farther from parent trees and in lower densities than lower quality seeds (Clarkson et al. 1986, Stapanian & Smith 1978, Tamura et al. 1999). Comparisons of seed removal rates among tropical tree species in South-East Asia (Blate et al. 1998) and Australia (Osunkoya 1994) failed to show a relationship between seed size and removal rate, although the probability that a seed was scatterhoarded by agoutis (Dasyprocta punctata) in a neotropical rain forest increased with interspecific seed size (Forget et al. 1998).
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Suni, T., L. Sogacheva, J. Lauros, H. Hakola, J. Bäck, T. Kurtén, H. Cleugh et al. "Cold oceans enhance terrestrial new-particle formation in near-coastal forests". Atmospheric Chemistry and Physics 9, n.º 22 (16 de noviembre de 2009): 8639–50. http://dx.doi.org/10.5194/acp-9-8639-2009.
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Abstract. The world's forests produce atmospheric aerosol by emitting volatile organic compounds (VOC) which, after being oxidized in the atmosphere, readily condense on the omnipresent nanometer-sized nuclei and grow them to climatically relevant sizes. The cooling effect of aerosols is the greatest uncertainty in current climate models and estimates of radiative forcing. Therefore, identifying the environmental factors influencing the biogenic formation of aerosols is crucial. In this paper, we connected biogenic aerosol formation events observed in a Eucalypt forest in South-East Australia during July 2005–December 2006 to air mass history using 96-h back trajectories. Formation of new particles was most frequent in the dry westerly and south-westerly air masses. According to NDVI (Normalized Difference Vegetation Index) measurements, photosynthesis was not significantly higher in this direction compared to the north-east direction. It is unlikely, therefore, that differences in photosynthesis-derived organic precursor emissions would have been significant enough to lead to the clear difference in NPF frequency between these two directions. Instead, the high evaporation rates above the Pacific Ocean resulted in humid winds from the north-east that effectively suppressed new-particle formation in the forest hundreds of kilometers inland. No other factor varied as significantly in tune with new-particle formation as humidity and we concluded that, in addition to local meteorological factors in the forest, the magnitude of evaporation from oceans hundreds of kilometers upwind can effectively suppress or enhance new-particle formation. Our findings indicate that, unlike warm waters, the cold polar oceans provide excellent clean and dry background air that enhances aerosol formation above near-coastal forests in Fennoscandia and South-East Australia.
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Moseby, K. E., H. McGregor y J. L. Read. "Effectiveness of the Felixer grooming trap for the control of feral cats: a field trial in arid South Australia". Wildlife Research 47, n.º 8 (2020): 599. http://dx.doi.org/10.1071/wr19132.
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Abstract ContextFeral cats pose a significant threat to wildlife in Australia and internationally. Controlling feral cats can be problematic because of their tendency to hunt live prey rather than be attracted to food-based lures. The Felixer grooming trap was developed as a targeted and automated poisoning device that sprays poison onto the fur of a passing cat, relying on compulsive grooming for ingestion. AimsWe conducted a field trial to test the effectiveness of Felixers in the control of feral cats in northern South Australia where feral cats were present within a 2600-ha predator-proof fenced paddock. MethodsTwenty Felixers were set to fire across vehicle tracks and dune crossings for 6 weeks. Cat activity was recorded using track counts and grids of remote camera traps set within the Felixer Paddock and an adjacent 3700-ha Control Paddock where feral cats were not controlled. Radio-collars were placed on six cats and spatial mark–resight models were used to estimate population density before and after Felixer deployment. Key resultsNone of the 1024 non-target objects (bettongs, bilbies, birds, lizards, humans, vehicles) that passed a Felixer during the trial was fired on, confirming high target specificity. Thirty-three Felixer firings were recorded over the 6-week trial, all being triggered by feral cats. The only two radio-collared cats that triggered Felixers during the trial, died. Two other radio-collared cats appeared to avoid Felixer traps possibly as a reaction to previous catching and handling rendering them neophobic. None of the 22 individually distinguishable cats targeted by Felixers was subsequently observed on cameras, suggesting death after firing. Felixer data, activity and density estimates consistently indicated that nearly two-thirds of the cat population was killed by the Felixers during the 6-week trial. ConclusionsResults suggest that Felixers are an effective, target-specific method of controlling feral cats, at least in areas in which immigration is prevented. The firing rate of Felixers did not decline significantly over time, suggesting that a longer trial would have resulted in a higher number of kills. ImplicationsFuture studies should aim to determine the trade-off between Felixer density and the efficacy relative to reinvasion.
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Hagemann, S., C. Chen, D. B. Clark, S. Folwell, S. N. Gosling, I. Haddeland, N. Hanasaki et al. "Climate change impact on available water resources obtained using multiple global climate and hydrology models". Earth System Dynamics 4, n.º 1 (7 de mayo de 2013): 129–44. http://dx.doi.org/10.5194/esd-4-129-2013.
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Abstract. Climate change is expected to alter the hydrological cycle resulting in large-scale impacts on water availability. However, future climate change impact assessments are highly uncertain. For the first time, multiple global climate (three) and hydrological models (eight) were used to systematically assess the hydrological response to climate change and project the future state of global water resources. This multi-model ensemble allows us to investigate how the hydrology models contribute to the uncertainty in projected hydrological changes compared to the climate models. Due to their systematic biases, GCM outputs cannot be used directly in hydrological impact studies, so a statistical bias correction has been applied. The results show a large spread in projected changes in water resources within the climate–hydrology modelling chain for some regions. They clearly demonstrate that climate models are not the only source of uncertainty for hydrological change, and that the spread resulting from the choice of the hydrology model is larger than the spread originating from the climate models over many areas. But there are also areas showing a robust change signal, such as at high latitudes and in some midlatitude regions, where the models agree on the sign of projected hydrological changes, indicative of higher confidence in this ensemble mean signal. In many catchments an increase of available water resources is expected but there are some severe decreases in Central and Southern Europe, the Middle East, the Mississippi River basin, southern Africa, southern China and south-eastern Australia.
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Cross, Roger, Andrew Bonney, Darren J. Mayne y Kathryn M. Weston. "Cross-sectional study of area-level disadvantage and glycaemic-related risk in community health service users in the Southern.IML Research (SIMLR) cohort". Australian Health Review 43, n.º 1 (2019): 85. http://dx.doi.org/10.1071/ah16298.
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Objectives The aim of the present study was to determine the association between area-level socioeconomic disadvantage and glycaemic-related risk in health service users in the Illawarra–Shoalhaven region of New South Wales, Australia. Methods HbA1c values recorded between 2010 and 2012 for non-pregnant individuals aged ≥18 years were extracted from the Southern.IML Research (SIMLR) database. Individuals were assigned quintiles of the Socioeconomic Indices for Australia (SEIFA) Index of Relative Socioeconomic Disadvantage (IRSD) according to their Statistical Area 1 of residence. Glycaemic risk categories were defined as HbA1c 5.0–5.99% (lowest risk), 6.0–7.49% (intermediate risk) and ≥7.5% (highest risk). Logistic regression models were fit with glycaemic risk category as the outcome variable and IRSD as the study variable, adjusting for age and sex. Results Data from 29064 individuals were analysed. Higher disadvantage was associated with belonging to a higher glycaemic risk category in the fully adjusted model (most disadvantaged vs least disadvantaged quintile; odds ratio 1.74, 95% confidence interval 1.58, 1.93; P<0.001). Conclusion In this geocoded clinical dataset, area-level socioeconomic disadvantage was a significant correlate of increased glycaemic-related risk. Geocoded clinical data can inform more targeted use of health service resources, with the potential for improved health care equity and cost-effectiveness. What is known about the topic? The rapid increase in the prevalence of Type 2 diabetes (T2D), both globally and nationally within Australia, is a major concern for the community and public health agencies. Individual socioeconomic disadvantage is a known risk factor for abnormal glucose metabolism (AGM), including T2D. Although small-area-level socioeconomic disadvantage is a known correlate of AGM in Australia, less is known of the association of area-level disadvantage and glycaemic-related risk in individuals with AGM. What does this paper add? This study demonstrates a robust association between small-area-level socioeconomic disadvantage and glycaemic-related risk in regional New South Wales. The study demonstrates that it is feasible to use geocoded, routinely collected clinical data to identify communities at increased health risk. What are the implications for practitioners? The identification of at-risk populations is an essential step towards targeted public health policy and programs aimed at reducing the burden of AGM, its complications and the associated economic costs. Collaboration between primary care and public health in the collection and use of data described in the present study has the potential to enhance the effectiveness of both sectors.
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Evans, J., A. M. McNeill, M. J. Unkovich, N. A. Fettell y D. P. Heenan. "Net nitrogen balances for cool-season grain legume crops and contributions to wheat nitrogen uptake: a review". Australian Journal of Experimental Agriculture 41, n.º 3 (2001): 347. http://dx.doi.org/10.1071/ea00036.
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The removal of nitrogen (N) in grain cereal and canola crops in Australia exceeds 0.3 million t N/year and is increasing with improvements in average crop yields. Although N fertiliser applications to cereals are also rising, N2-fixing legumes still play a pivotal role through inputs of biologically fixed N in crop and pasture systems. This review collates Australian data on the effects of grain legume N2 fixation, the net N balance of legume cropping, summarises trends in the soil N balance in grain legume–cereal rotations, and evaluates the direct contribution of grain legume stubble and root N to wheat production in southern Australia. The net effect of grain legume N2 fixation on the soil N balance, i.e. the difference between fixed N and N harvested in legume grain (Nadd) ranges widely, viz. lupin –29–247 kg N/ha (mean 80), pea –46–181 kg N/ha (mean 40), chickpea –67–102 kg N/ha (mean 6), and faba bean 8–271 kg N/ha (mean 113). Nadd is found to be related to the amount (Nfix) and proportion (Pfix) of crop N derived from N2 fixation, but not to legume grain yield (GY). When Nfix exceeded 30 (lupin), 39 (pea) and 49 (chickpea) kg N/ha the N balance was frequently positive, averaging 0.60 kg N/kg of N fixed. Since Nfix increased with shoot dry matter (SDM) (21 kg N fixed/t SDM; pea and lupin) and Pfix (pea, lupin and chickpea), increases in SDM and Pfix usually increased the legume’s effect on soil N balance. Additive effects of SDM, Pfix and GY explained most (R2 = 0.87) of the variation in Nadd. Using crop-specific models based on these parameters the average effects of grain legumes on soil N balance across Australia were estimated to be 88 (lupin), 44 (pea) and 18 (chickpea) kg N/ha. Values of Nadd for the combined legumes were 47 kg N/ha in south-eastern Australia and 90 kg N/ha in south-western Australia. The average net N input from lupin crops was estimated to increase from 61 to 79 kg N/ha as annual rainfall rose from 445 to 627 mm across 3 shires in the south-east. The comparative average input from pea was 37 to 47 kg N/ha with least input in the higher rainfall shires. When the effects of legumes on soil N balance in south-eastern Australia were compared with average amounts of N removed in wheat grain, pea–wheat (1:1) sequences were considered less sustainable for N than lupin–wheat (1:1) sequences, while in south-western Australia the latter were considered sustainable. Nitrogen mineralised from lupin residues was estimated to contribute 40% of the N in the average grain yield of a following wheat crop, and that from pea residues, 15–30%; respectively, about 25 and 15 kg N/ha. Therefore, it was concluded that the majority of wheat N must be obtained from pre-existing soil sources. As the amounts above represented only 25–35% of the total N added to soil by grain legumes, the residual amount of N in legume residues is likely to be important in sustaining those pre-existing soil sources of N.
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GIDDING, H. F., J. AMIN, G. J. DORE y M. G. LAW. "Hospitalization rates associated with hepatitis B and HIV co-infection, age and sex in a population-based cohort of people diagnosed with hepatitis C". Epidemiology and Infection 139, n.º 8 (19 de noviembre de 2010): 1151–58. http://dx.doi.org/10.1017/s095026881000258x.
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SUMMARYTo determine the extent age, sex and co-infection affect morbidity in people infected with hepatitis C virus (HCV), we performed a population-based study linking HCV notifications in New South Wales, Australia with their hospital (July 2000 to June 2006), hepatitis B virus (HBV) and HIV notification, and death records. Poisson models were used to calculate hospitalization rate ratios (RRs) for all-cause, illicit drug and liver-related admissions. Co-infection RRs were used to estimate attributable risk (AR). The 86 501 people notified with HCV contributed 422 761 person-years of observation; 0·8% had HIV, 3·7% HBV, and 0·04% had both. RRs for males were equal to or lower than for females in younger ages, but higher in older ages (Pfor interaction ⩽0·013). HBV/HIV co-infection resulted in ARs of over 70% for liver disease and 30–60% otherwise. However, at the cohort level the impact was minimal (population ARs 1·3–8·7%). Our findings highlight the importance and success of public health measures, such as needle and syringe exchange programmes, which have helped to minimize the prevalence of co-infection in Australia. The findings also suggest that the age of study participants needs to be considered whenever the burden of HCV-related morbidity is reported by sex. The results are likely to be representative of patterns in hospital-related morbidity for the entire HCV-infected population in Australia and the ARs generalizable to other developed countries.
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Parnaby, Harry, Daniel Lunney, Ian Shannon y Mike Fleming. "Collapse rates of hollow-bearing trees following low intensity prescription burns in the Pilliga forests, New South Wales". Pacific Conservation Biology 16, n.º 3 (2010): 209. http://dx.doi.org/10.1071/pc100209.
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Hollows in trees are recognized as a critical and threatened resource for a wide range of fauna in Australian forests and woodlands, yet little data are available on the impact of fire on hollow-bearing trees. We report an opportunistic, post-fire assessment of the proportion of burnt, hollow-bearing trees that collapsed in stands near roads following low intensity prescription burns in three areas of mixed eucalypt forest in the Pilliga forests. Mean collapse rates on 29 plots (40 by 50m), separated by burn Area, ranged from 14?26% for a total of 329 burnt hollow-bearing trees. Collapse rates on individual plots ranged from 0?50%. Collapsed, hollow-bearing trees were predominantly older, with 40% of senescent trees and 44% of live stags collapsing. The best predictor in models of tree collapse was the presence of a basal fire entry point. We cannot determine the extent to which collapse rates on our plots are representative of burnt areas away from containment roads due to sampling limitations, but they appear to be higher than those reported from wildfire and more intense prescription burns in southern Australia. Our results point to an urgent need for comprehensively designed studies to address the impacts of prescribed burns on hollow-bearing trees.