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[en] Much of southern and eastern Australia including Queensland have experienced rainfall declines over recent decades affecting agricultural production and accelerating water infrastructure development. Rainfall declines from southern Australia have now been directly related to changes in the Southern Annular Mode (SAM) and the subtropical ridge. In southern and coastal Queensland, the rainfall declines have occurred mostly in the austral summer and autumn. Observations from this region reveal the rainfall decline is correlated to an increase in the mean sea level pressure (MSLP) at many stations. The largest increases in MSLP are over southeast Queensland and coastal regions, where some of the largest rainfall declines occur. This study indicates the subtropical ridge as one of the main factors in the rainfall decline over this region. SAM is also likely to be important, although its seasonal influence, apart from winter, is harder to determine.
[en] Cs-137 measurements for the 0-10 cm soil depth are presented, together with the paddock slope profile. The trend for lower activities in the region of maximum slope and the high activity at the bottom of the slope is apparent. However, the variability is considerable and this makes quantitative assessment difficult. The study used a Li-drifted Ge 12% detector which allowed only one sample per day to be counted. This is a major problem with the Cs-137 technique
[en] Wind records at Brisbane indicate past changes in ambient weather systems that appear to be confirmed by observed changes in Australian rainfalls. Both wind and rainfall data support geological field evidence of a climatic change in southeast Queensland in the 1930s. At Brisbane the numbers of calms observed in January and July declined from 1887 to 1935, and then increased again. This variation was associated with changes in wind patterns, particularly in winter (July) from 1933 to 1937 and afterwards, but also in summer (January) during the 1930s. The changes in circulation were enough to explain the movement of beach and dune sands at that time. The changes in windiness show a close connection with the 80-year trend in sunspot number: the initial period of below average sunspot number coincided with increasing wind strength and more southeasterly winds. Rainfall trends show similar associations with sunspot trends, but the direction of rainfall change is different in different regions. In southeast Australia changes in rainfall are positively correlated with trends in sunspot number over the last 80 years, while the opposite holds for the far southwest and Cape York Peninsula. On the north coast negative correlations occur in summer, and positive correlations in winter, but in Queensland and western New South Wales the correlations are positive in summer and negative in winter. It is too soon to tell whether the connection between sunspots and weather is accidental or functional. (Auth.)
[en] Highlights: • Political factors are significant drivers of deforestation. • Regulation reduced deforestation inconsistently across forests types and regions. • Policy uncertainty increased deforestation, particularly in remnant forests. • Perverse outcomes delayed forest transition and may reverse further transition. • Focusing on forest gains will ignore biodiversity threats of remnant forest loss. - Abstract: Policy-driven shifts from net deforestation to forest expansion are being stimulated by increasing social preferences for forest ecosystem services. However, policy uncertainty can disrupt or reverse the positive effects of forest transitions. For instance, if the loss of remnant (primary) forest continues, the ecological benefits of net forest gains may be small. We investigated how peak periods of uncertainty in forest conservation policy affected forest transition outcomes in Queensland, Australia, as well as a globally-relevant biodiversity hotspot in the state, the Brigalow Belt South (BBS) bioregion. Political, socioeconomic, and biophysical factors associated with net forest cover change and remnant forest loss from 1991 to 2014 were identified through spatial longitudinal analysis. This informed a Bayesian structural causal impact assessment of command-and-control regulation and policy uncertainty on remnant and non-remnant forest cover. The results indicate that forest cover was negatively influenced by increasing temperatures, food prices, and policy uncertainty, and positively influenced by strengthening regulation. Regulation during 2007–2014 avoided 68,620 ± 19,214 km2 of deforestation (with 18,969 ± 10,340 km2 of this in remnant forests) throughout Queensland, but was ineffective on remnant forests in the BBS. For state-wide remnant forests, perverse effects from policy uncertainty (e.g. pre-emptive deforestation) were strong enough to negate regulatory impacts. This study reveals a cautionary tale for conservation policy: despite strict environmental regulations, forest transition can be delayed (or reversed) when political inconsistency or instability provoke unintended reactions from landholders.
[en] It is generally accepted that the enrichment of natural 15N abundance in soil over time is reflective of historic N cycling and loss, but this process in cropping soils is not yet clear. In this study, we identified an enrichment gradient of natural 15N abundance during 20-year chronosequence of cereal cropping on Alfisols in southwest Queensland, Australia, that have no history of fertilisation. We demonstrate that the increase in soil 15N abundance is explained by isotopic fractionation of 15N during organic N mineralisation and nitrification, which lead to isotopically heavier ammonium retained in the soil and isotopically lighter soil nitrate taken up and removed by seasonal crops during harvest. Here we present a framework for natural 15N isotopic fractionation co-occurring with N losses during long-term cultivation. - Highlights: • A gradient of 15N enrichment was identified along a 20-year crop chronosequence. • A mechanism responsible for 15N enrichment during crop-soil N losses is proposed. • 15N abundance can be a useful tracer of cropping soil N loss in absence of fertilisers.
[en] The potential application of ionising energy treatment technology in Queensland falls into three categories: insect disinfestation, disease control and quality improvement. The technology fulfils the requirements of a disinfestation treatment against Queensland fruit fly and other pests of quarantine importance in respect to efficacy, absence of phytotoxicity, absence of residues and, on technical considerations would be an ideal replacement for the fumigant EDB. The report examines the purposes of ionising energy treatment, economic and marketing aspects and research needs
[en] This paper outlines the reasons behind carry out a study of clinical performance skills requirements and the method being used to gather data. It describes the changes which have occurred in radiographer education in Queensland, the broader impact brought about by changes in professional body requirements and the development of a Competency based Standards Document for the profession. The paper provides examples of the survey design and layout being developed for distribution to third year students in the Medical Imaging Technology major of the Bachelor of Applied Science (Medical Radiation Technology) Queensland University of Technology, graduates and clinical departments in Queensland. 1 tab., 1 fig
[en] The solar ultraviolet radiation (UVR) exposures of three groups of outdoor workers, physical education (PE) teachers, ground staff/gardeners and lifeguards were measured using UVR-sensitive polysulfone (PS) film badges. The exposures all took place on the Sunshine Coast, Queensland over 5 consecutive weekdays in November 1992. For the three groups, the shoulder badges received greater UVR exposures than the chest badges, in agreement with previous studies. The PE teachers received the highest UVR exposures while the lifeguards received the least. One of the 5 days of the study was overcast with some rain showers and UVR doses for this day for all groups was significantly lower than on the other 4 days, however the ratio of exposure to ambient remained relatively constant. All groups had measured UVR exposures in excess of occupational guidelines, indicating that protective measures, including education and behaviour modification, which are becoming much more common in occupational situations in Australia, are both timely and necessary. (author)
[en] This paper examines the feasibility of utilising an irradiation plant to disinfest fresh fruit and vegetables destined for export markets. It examines the export market potential of selected crops with the prime view of estimating likely trends in export markets in the future. These trends will have a significant bearing on throughput levels, and hence on the economic viability of an ionising energy plant