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As the global population rises, there is an ever-increasing demand for food, in terms of volume, quality and sustainable production. Protected Cropping Structures (PCS) provide controlled farming environments that support the optimum use of crop inputs for plant growth, faster production cycles, multiple growing seasons per annum and increased yield, while offering greater control of pests, disease and adverse weather. Globally, there has been a rapid increase in the adoption of PCS. However, there remains a concerning knowledge gap in the availability of accurate and up-to-date spatial information that defines the extent (location and area) of PCS. This data is fundamental for providing metrics that inform decision making around forward selling, labour, processing and infrastructure requirements, traceability, biosecurity and natural disaster preparedness and response. This project addresses this need, by developing a national map of PCS for Australia using remotely sensed imagery and deep learning analytics, ancillary data, field validation and industry engagement. The resulting map presents the location and extent of all commercial glasshouses, polyhouses, polytunnels, shadehouses and permanent nets with an area of >0.2 ha. The outcomes of the project revealed deep learning techniques can accurately map PCS with models achieving F-Scores > 0.9 and accelerate the mapping where suitable imagery is available. Location-based tools supported by web mapping applications were critical for the validation of PCS locations and for building industry awareness and engagement. The final national PCS map is publicly available through an online dashboard which summarises the area of PCS structures at a range of scales including state/territory, local government area and individual structure. The outcomes of this project have set a global standard on how this level of mapping can be achieved through a collaborative, multifaceted approach. [ABSTRACT FROM AUTHOR]

In this study, benthic flux measurements of inorganic nitrogen (i.e., $$ {\text{NH}}^{ + }_{4} $$ , $$ {\text{NO}}^{ - }_{2} $$ + $$ {\text{NO}}^{ - }_{3} $$ ) were made using a batch incubation system at different stations (i.e., shallow sandy macrophyte and unvegetated beds, and deep central mud) over four seasons in Lake Illawarra, NSW, Australia, to study the influence of different primary producers (i.e., seagrasses, microphytobenthos (MPB) and macroalgae) and/or different sediment types (i.e., sand or mud) on the benthic fluxes. In general, nutrient fluxes displayed typical diel variations, with lower flux out of sediments (release) or enhanced uptake by the sediment in the light, due to the photosynthetic activities of the plant-MPB-sediment community in Lake Illawarra during photosynthetic periods. A distinct seasonal pattern of inorganic-N fluxes was also observed (e.g., the marked difference between summers 2002 and 2003). This may be explained by the seasonal variations in the biomass and activity (growing or decay phases) of MPB, seagrass and macroalgae, which may influence their nutrient assimilation and alter the chemical conditions of surface sediments that influence the benthic geochemical processes and thus benthic nutrient fluxes. On an annual basis, unvegetated sediments displayed net DIN effluxes, while seagrass beds showed a net DIN uptake, and the highest DIN uptakes coincided with the largest standing crop of seagrass and/or macroalgae and the highest levels of benthic community production. This may be due to the enhanced denitrification and/or assimilation activity by rooted plants and macroalgae, and the effect is most efficient during periods of net growth (e.g., in Spring 2002). [ABSTRACT FROM AUTHOR]

Benthic flux measurements of O2, TCO2 and inorganic nutrients were made at three stations (seagrass beds, shallow bare sand and deep mud) in Lake Illawarra (Australia) to compare the characteristics of diagenesis and benthic biogeochemical processes for different primary producers (seagrass or microphytobenthos, (MPB)) and/or sediment types (sand or mud).Seagrass beds exhibited the highest gross primary productivity while the lowest rates occurred at the deep mud station. At the shallow bare sand station only, the gross primary production (GPP) and respiration (R) were balanced, while at the other two stations, R exceeded GPP by as much as 2 fold, indicating more organic carbon was decomposed than produced at the time of sampling. In general, nutrient fluxes displayed typical diurnal variation.Organic carbon oxidation scenarios, evaluated by either calcium carbonate dissolution or sulfate reduction models, indicated that both models can represent organic matter mineralization. The difference of estimated total carbon oxidized in this lake using the two models was small, ranging from 0.2% at deep mud station to maximum of 21% at seagrass station. In addition, N2 flux rates (net denitrification), estimated using carbon and nitrogen stoichiometry, were of similar magnitude as the rates estimated using LOICZ budget modeling or measured using the N2/Ar technique.Finally, a comparison of calculated diffusive fluxes and measured fluxes using incubation cores indicated that the results were of similar magnitude at the deep mud station, but the incubation cores fluxes were much higher than the calculated diffusive fluxes at the other two stations. This may have been caused by bioturbation or bioirrigation. [ABSTRACT FROM AUTHOR]

Rates of inorganic nutrient and oxygen fluxes, and gross community primary productivity were investigated using incubated cores in July, August and September 2001, in a seagrass meadow of Lake Illawarra, a barrier estuary in New South Wales, Australia. The results indicated that rates of gross primary productivity were high, varying from C = 0.62 to 1.89 g m-2 d-1; low P/R ratios of 0.28–0.48 define the system as heterotrophic and indicate that more carbon is respired than is produced. In order to determine the effect of macroalgae on O2 and nutrient fluxes, measurements were also conducted on cores from which the macroalgae had been removed. The results showed that the O2 fluxes during light incubations were significantly lower in the cores without macroalgae (P<0.01), indicating that macroalgae could be a significant contributor to the primary production in the lake. In general, nutrient fluxes showed a typical diurnal variation with an efflux from sediments in the dark and a reduced efflux (or uptake) in the light. Dissolved inorganic nitrogen (NO2-+ NO3-+NH4+) net fluxes were directed from the sediments towards the water column and dominated by the NH4+ fluxes (>80%). NO2-+ NO3- and o-P fluxes were always very low during the sampling period. The increasing tendency of net nutrient effluxes, especially NH4+ from July to September, is consistent with the increase of the water temperature and seagrass biomasses. However, in September, significantly lower light, dark and net NH4+ effluxes were found in the cores with macroalgae (SA-sediments) compared with the cores without macroalgae (S-sediments). These results support the hypothesis that actively-growing dense macroalgal mats (i.e., algal blooms in September) may act as a filter reducing the flux of nutrients to the water column. [ABSTRACT FROM AUTHOR]

A detailed geochemical analysis of sediment samples from the heavily industrialised Port Kembla Harbour, 70 km south of Sydney in New South Wales, Australia, has delineated areas that are heavily contaminated with trace element pollutants. Local creek delta sand accumulations, basin mud deposits, reclamation deposits and exposed bedrock on the present harbour floor are consistent with the twentieth century Port Kembla industrial land and harbour development history, as well as known maritime shipping practices. The closed electrolytic copper refinery, one of the two major pollutant sources, has provided a very clear signature in the harbour opposite the main drain that discharged from these works. Copper pollution (up to 6070 mg/kg) is strongly correlated with high concentrations of gold, selenium, antimony, arsenic, lead and zinc. These pollutants appear to occur as silt- and sand-sized particulate matter, as well as pollutants that are probably chemically bound to clay, pyrite and organic matter. The second main pollutant source is the BlueScope steelworks that has been responsible for high concentrations of iron (and minor associated cobalt), kish, pyrolytic carbon and fly ash. The steelworks, along with other industrial, urban and automobile sources, supply additional quantities of copper, lead and zinc to the aquatic environment. Coal and coke dust also form important pollutants. The pollutants are currently fairly stable under the prevailing alkaline reducing conditions within the sediment. The proposed future reclamation and dredging within the harbour needs to consider the implications of moving highly contaminated sediment, without altering its alkalinity or oxidation potential, to prevent release of contaminants. [ABSTRACT FROM AUTHOR]

The impact of fire on global C cycles is considerable but complex. Nevertheless, studies on patterns of soil C accumulation following fires of differing intensity over time are lacking. Our study utilised 15 locations last burnt by prescribed fire (inferred low intensity) and 18 locations last burnt by wildfire (inferred high intensity), with time since fire (TSF) up to 43 years, in a homogenous forest type in south eastern Australia. Following a stratified approach to mineral soil sampling, the soil % total C (% C Tot ) and % recalcitrant pyrogenic C (% RPC), were estimated. Generalised additive models indicated increases in % C Tot at TSF > 30 years in sites last burnt by wildfire. Estimates in sites last subjected to prescribed fire however, remained constant across the TSF chronosequence. There was no significant difference in % C Tot between the different fire types for the first 20 years after fire. In the first 10 years after wildfires, % RPC was elevated, declining to a minimum at ca. TSF 25 years. After prescribed fires, % RPC was unaffected by TSF. Differences in response of % C Tot and % RPC to fire type may reflect the strength of stimulation of early successional processes and extent of charring. The divergent response to fire type in % C Tot was apparent at TSF longer than the landscape average fire return interval (i.e., 15 to 20 years). Thus, any attempt to increase C sequestration in soils would require long-term exclusion of fire. Conversely, increased fire frequency is likely to have negligible impact on soil C stocks in these forests. Further investigation of the effects of fire frequency, fire intensity combinations and interaction of fire with other disturbances will enhance prediction of the likely impact of imposed or climatically induced changes to fire regimes on soil C. [ABSTRACT FROM AUTHOR]

Background: According to the Grattan institute in 2014, 70% of Australians indicated a preference to die at home, however, only 14% of all deaths were at home., Aims: To identify how patients can be supported to die at home if that is their preference., Methods: A retrospective medical record audit of eligible Community Palliative Care (CPC) patients who indicated a wish to die at home was undertaken., Findings: Out of a total of 114 patients, 74% indicated a preference to die at home. Of these, 66% achieved a home death, and most lived with a carer. Enablers for home death included family support, regular nursing visits and equipment. People who attended an emergency department in their last month of life, lived alone or were undergoing oncological treatment were more likely to die elsewhere., Conclusion: A range of enablers and barriers to home death were found, with many of the enablers being factors that prevented hospital presentations.

Food manufacturers are increasingly substituting potassium chloride (KCl) in food products so as to reduce the sodium chloride content. Bread and bread products are common staple foods in many Western households and are a target for recipe reformulation using KCl. Given that chronic kidney disease (CKD) is a medical condition of global importance that requires dietary potassium restriction in the later stages, we sought to evaluate the impact and safety of varying levels of KCl substitution in bread products. We undertook a secondary analysis of dietary data from the National Nutrition and Physical Activity Survey 2011-2012 for 12,152 participants (154 participants with CKD). The sodium chloride content in bread and bread-based products was substituted with 20%, 30%, and 40% of KCl. The contribution of these alterations in the dietary potassium intake to the total daily potassium intake were then examined. The replacement of sodium in bread with varying amounts of KCl (20%, 30%, and 40%) resulted in one third of people with CKD exceeding the safe limits for dietary potassium consumption (31.8%, 32.6%, and 33%, respectively). KCl substitution in staple foods such as bread and bread products have serious and potentially fatal consequences for people who need to restrict dietary potassium. Improved food labelling is required for consumers to avoid excessive consumption.

Purpose: To explore the experiences of friendship for children with disabilities who attend mainstream Australian schools., Background: Being a friend is an important occupational role for all children. However, the literature suggests that physical inclusion of children with disabilities in mainstream schools does not necessarily develop social inclusion., Methods: Phenomenology was used to explore friendship experiences of 10 primary school children with disabilities., Findings: Five themes emerged from the data: (1) self-identity; (2) meaning of friendship; (3) classroom experiences; (4) playing together; (5) longing for friendship. These themes reflected the importance of friendship in the children's lives, the influence of the children's beliefs and values, and the impact of the attitudes and actions of educational staff and other students., Implications: Occupational therapists need to work collaboratively with educational staff, students, and their peers to create inclusive school settings that facilitate positive friendship experiences for children with disabilities.