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Summary: This paper describes advances made to aerial surveys of macropods in New South Wales and Queensland. Regular aerial surveys of macropods across large areas of Australia's arid and semi‐arid rangelands were established as a response to concerns for the species' conservation. They became integral to the harvest management of the four macropod species – Eastern Grey Kangaroo (Macropus giganteus), Western Grey Kangaroo (M. fuliginosus), Red Kangaroo (Osphranter rufus) and Common Wallaroo (O. robustus). Harvest quotas are set as a proportion of population size, requiring absolute estimates of abundance. Counts were made in strip transects from fixed‐wing aircraft, but required correction for animals that are missed. In New South Wales and Queensland, counts are now made using line transect sampling, providing survey‐specific correction. Helicopters are used in more rugged and timbered areas and where Common Wallaroo can be more frequently found and harvested. Mark‐recapture distance sampling is used in more open country that can be surveyed using fixed‐wing aircraft and improves the accuracy of density estimates by accounting for animals missed on the transect line. Macropod populations are likely to be surveyed in the future by airborne imagery and by drones, but the technology needs further development. Spatial models could usefully provide small‐scale density estimates and address non‐random sampling. [ABSTRACT FROM AUTHOR]

The paper examines whether there was an excess of deaths and the relative role of temperature and ozone in a heatwave during 7–26 February 2004 in Brisbane, Australia, a subtropical city accustomed to warm weather. The data on daily counts of deaths from cardiovascular disease and non-external causes, meteorological conditions, and air pollution in Brisbane from 1 January 2001 to 31 October 2004 were supplied by the Australian Bureau of Statistics, Australian Bureau of Meteorology, and Queensland Environmental Protection Agency, respectively. The relationship between temperature and mortality was analysed using a Poisson time series regression model with smoothing splines to control for nonlinear effects of confounding factors. The highest temperature recorded in the 2004 heatwave was 42°C compared with the highest recorded temperature of 34°C during the same periods of 2001–2003. There was a significant relationship between exposure to heat and excess deaths in the 2004 heatwave [estimated increase in non-external deaths: 75 ([95% confidence interval, CI: 11–138; cardiovascular deaths: 41 (95% CI: −2 to 84)]. There was no apparent evidence of substantial short-term mortality displacement. The excess deaths were mainly attributed to temperature but exposure to ozone also contributed to these deaths. [ABSTRACT FROM AUTHOR]

Research Highlights: This study evaluated the impacts of biomass recovery on site preparation costs while proposing a mathematical model and framework to catalogue the benefits depending on harvesting system. Background and Objectives: Biomass as a viable product depends on the requisite costs of production compared to the price paid by relative markets. The removal of biomass directly impacts site preparation costs, and the operational and economic ramifications of this should inform the feasibility of biomass harvesting and market viability. The relative incentives for biomass removal depend on the quantity, presentation, and location of the residues and are thus a result of the commercial sawlog harvesting system. This incentive also largely depends on the required work to prepare a site for replanting. Materials and Methods: This study developed a mathematical model to connect the concepts of site preparation, harvesting, and biomass costs and revenues to determine the maximum net revenue. This work also developed a framework for understanding and calculating the key model inputs related to site preparation and the relative economic site preparation incentive for biomass harvesting. The framework was then illustrated by using industry data from plantations in Queensland, Australia. Results and Conclusions: The analysis identified a potential reduction in site preparation costs due to biomass harvesting of USD 75–450 ha−1, with a greater incentive when using cut-to-length harvesting systems compared with whole-tree harvesting due to the greater volume of residues after cut-to-length harvesting. For example, a removal of 20 t ha−1 of recoverable biomass after cut-to-length harvesting may equate to an economic incentive of USD 22 t−1. Depending on the biomass market, this incentive may represent a significant percentage (or even exceed) the biomass market price. The combination of biomass market price plus site preparation economic incentive may make biomass an attractive market opportunity, even in challenging biomarkets. [ABSTRACT FROM AUTHOR]