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With the addition of nitrogen (N), agricultural soils are the main anthropogenic source of N2O, but high spatial and temporal variabilities make N2O emissions difficult to characterize at the field scale. This study used flux‐gradient measurements to continuously monitor N2O emissions at two agricultural fields under different management regimes in the inland Pacific Northwest of Washington State, USA. Automated 16‐chamber arrays were also deployed at each site; chamber monitoring results aided the interpretation of the flux gradient results. The cumulative emissions over the six‐month (1 April–30 September) monitoring period were 2.4 ± 0.7 and 2.1 ± 2 kg N2O‐N/ha at the no‐till and conventional till sites, respectively. At both sites, maximum N2O emissions occurred following the first rainfall event after N fertilization, and both sites had monthlong emission pulses. The no‐till site had a larger N2O emission factor than the Intergovernmental Panel on Climate Change Tier 1 emission factor of 1% of the N input, while the conventional‐till site's emission factor was close to 1% of the N input. However, these emission factors are likely conservative. We estimate that the global warming potential of the N2O emissions at these sites is larger than that of the no‐till conversion carbon uptake. We recommend the use of chambers to investigate spatiotemporal controls as a complementary method to micrometeorological monitoring, especially in systems with high variability. Continued monitoring coupled with the use of models is necessary to investigate how changing management and environmental conditions will affect N2O emissions. Plain Language Summary: Nitrous oxide (N2O) is a greenhouse gas and stratospheric ozone depleting substance that is emitted by soils. Agricultural soils tend to emit more N2O than natural soils due to the addition of nitrogen fertilizers. N2O emissions are not well understood on the scale of individual farms, as emissions are difficult to measure at this resolution because they are irregular over time and space. This variability is due to the dependence of N2O production and emission on soil properties, that is, moisture, nitrogen, and the microbiome. In this study we monitored N2O emissions from two agricultural fields under different tillage regimes using two complementary methods: the flux‐gradient technique and automated chambers. The flux‐gradient technique measures N2O emissions at the field scale, which is relevant to agronomic management. Using both techniques together improves confidence in our results, which give us information on total N2O emissions from these fields, as well as the relationships between N2O emissions and rainfall, temperature, and carbon dioxide respiration. Key Points: Total emissions from 1 April to 30 September 2015 were 2.4 ± 0.7 and 2.1 ± 0.2 kg N2O‐N/ha at the no‐ and conventional‐till sites, respectivelyN2O fluxes had similar responses to temperature and precipitation at both sitesHigh spatial variability at both sites (CVs > 140%) limited the ability of the chamber systems to characterize field‐scale N2O emissions [ABSTRACT FROM AUTHOR]

The Australian government deregulated the wheat export market in 2008, ending 60 years of statutory wheat marketing by the Australian Wheat Board (AWB). In this article, I explore the discursive shifts which contributed to this change. I adopt a genealogical approach to this research, by collecting and analysing policy documents produced between 1983 and 2012, to understand how truths—such as efficiency, competition and the ‘good farmer’—were constructed and reproduced to facilitate wheat export market deregulation in Australia. Through analysing the case of wheat export market deregulation, and the process by which this shift was made possible, this article contributes more broadly to research examining the neoliberalisation of Australian rural industries, and the discursive construction of norms, values and identities to facilitate these changes. [ABSTRACT FROM AUTHOR]

Efforts to improve energy efficiency in homes and buildings have led to tighter structures. However, these changes can also produce negative consequences for indoor air quality and human health. One of the dramatic effects of climate change and weather is the increase in destructive wildfires, such as those experienced in the Pacific Northwest during the summer of 2015. The current article presents data for measurements at two houses during periods with and without high levels of wildfire smoke outdoors. For each house, indoor and outdoor pollutant measurements were obtained for ozone (O3), fine particulate matter (PM2.5), and volatile organic compounds along with outdoor weather conditions and occupant activities including the use of windows and doors. The volatile organic compound measurements were obtained using a Proton Transfer Reaction Mass Spectrometer. Compounds monitored included acetonitrile (a biomass burning tracer), formaldehyde, acetaldehyde, methanol, acetone, benzene, toluene, and C2-alkylbenzenes (i.e., sum of xylenes and ethylbenzene), C3-alkylbenzenes (i.e., sum of trimethylbenzene, ethyltoluene, and propylbenzene isomers), and C4-alkylbenzenes (i.e., sum of tetramethylbenzene and its isomers). A carbon dioxide tracer method was used to measure in situ ventilation rates, and blower door tests were also completed to determine standard ventilation rates. For smoky periods with elevated outdoor pollutant levels, penetration factors, defined as the ratio of indoor/outdoor concentrations were quite low. Penetration factors for PM2.5 were 11% for H2 and 15% for H3, except when windows or doors were open. The penetration factors for O3 were also low at 24% for H2 and 5% for H3. Elevated indoor volatile organic compound levels were not typically associated with outdoor levels, but reflected significant indoor sources. During smoke events, acetonitrile, a biomass burning tracer compound, was elevated outdoors and indoors in both houses, and benzene was elevated outdoors and indoors in H3. [ABSTRACT FROM AUTHOR]

The Australian Government’s Agricultural Competitiveness White Paper aims to create a profitable and resilient Australian agriculture sector. In doing so, the White Paper emphasises farmers’ individual responses to the structural problems which have undermined farmers’ profitability, such as consolidated commodities markets. In particular, the White Paper recommends that farmers shape their farming practice to make their farms more attractive to private investors. This is presented as a normal response to farm profitability concerns. Farms are portrayed as investment targets and securing investment is framed as an essential skill of the modern farmer. To understand how this discursive construction has been made possible, this article develops a genealogical analysis of changing constructions of farmers, farming and of the role of the State. This research reveals the subtle discursive shifts which have helped shift responsibility for farming, from the State, to the self-reliant individual, and most recently, towards the private sector. Whereas the construct of the self-reliant, independent farmer has been used to facilitate deregulation of agricultural industries, this recent shift in power towards the private sector may potentially undermine farmers’ autonomy and increase dependence on private sector investment. [ABSTRACT FROM PUBLISHER]

AS THE RESOURCE SECTOR carries e Australian economy through the global financial crisis, significant uranium deposits lie dormant and undeveloped in Australia's outback. Spurred by the possibility of the Australian [...]

The X-ray absorption spectra (XAS) of Ar2 and ArNe dimers and small Ar clusters in the L2,3 region (244–252 eV) of the Ar atom have been recorded using synchrotron light and a combination of coincidence methods and kinetic energy discrimination of energetic ions. The absorption peaks in the spectra of the dimers and clusters were found to be shifted and broadened relative to the peaks in the spectrum of the Ar atom. In order to unambiguously relate these chemical shifts to the electronic structure of the core excited states in dimers, we performed ab initio calculations of the XAS spectra. Implications of the results for the use of XAS as a structure determination method in large rare gas clusters are discussed. [ABSTRACT FROM AUTHOR]

Mental illness impacts upon a significant percentage of tertiary students in Australia and the United States. The number of students with mental illness is increasing, as is the number of students experiencing serious psychological difficulties. The first onset of mental illness frequently occurring for people aged 18 to 24, which, coupled with the stress created by study and life pressures for graduate university students, ensures that students can be considered as a group which is at high risk of developing mental illness. However, the willingness of students with mental illness to voluntarily seek help remains low. Amongst other barriers, the fear of stigmatisation, and resulting self concealment of mental illness, ensures that many students with mental illness do not seek professional help. This paper contends that the provision of information on mental illness, information on campus based treatment opportunities and the creation of an open environment where mental illness can be discussed, are critical to the improvement of help seeking behaviour. However, this paper refers to data on counsellor to student ratios in Australia, as compared to the United States, which indicates that counselling centres within Australian universities may not be effectively resourced to cope with an increase in demand for counselling services. [ABSTRACT FROM AUTHOR]