Eco-hydrology of dynamic wetlands in an Australian agricultural landscape: a whole of system approach for understanding climate change impacts

Increasing rates of water extraction and regulation of hydrologic processes, coupled with destruction of natural vegetation, pollution and climate change, are jeopardizing the future persistence of wetlands and the ecological and socio-economic functions they support. Globally, it is estimated that 50% of wetlands have been lost since the 1900’s, with agricultural changes being the main cause. In some agricultural areas of Australia, losses as high as 98% have occurred. Wetlands remaining in agricultural landscapes suffer degradation and their resilience and ability to continue functioning under hydrologic and land use changes resulting from climate change may be significantly inhibited. However, information on floodplain wetlands is sparse and knowledge of how ecological functioning and resilience may change under future land use intensification and climate change is lacking in many landscapes. These knowledge gaps pose significant problems for the future sustainable management of biodiversity and agricultural activities which rely on the important services supplied by wetland ecosystems. This research evaluates the impact that hydrology and land use has on the perennial vegetation associated with wetlands in an agricultural landscape, the Condamine Catchment of southeast Queensland, Australia. A geographical information system (GIS) was used to measure hydrological and land use variables and a bayesian modeling averaging approach was used to generate generalised linear models for vegetation response variables. Connectivity with the river and hydrological variability had consistently significant positive relationships with vegetation cover and abundance. Land use practices such as, irrigated agriculture and grazing had consistently significant negative impacts. Consequently, to understand how climate change will impact on the ecohydrological functioning of wetlands, both hydrological and land use changes need to be considered. Results from this research will now be used to investigate how resilient these systems will be to different potential scenarios of climate change

Langmuir-Maxwell and Langmuir-Smoluchowski boundary conditions for thermal gas flow simulations in hypersonic aerodynamics

The simulation of nonequilibrium thermal gas flow is important for the aerothermodynamic design of re-entry and other high-altitude vehicles. In computational fluid dynamics, the accuracy of the solution to the Navier–Stokes–Fourier (N–S–F) equations depends on the accuracy of the surface boundary conditions. We propose new boundary conditions (called the Langmuir–Maxwell and the Langmuir–Smoluchowski conditions), for use with the N–S–F equations, which combine the Langmuir surface adsorption isotherm with the Maxwell/Smoluchowski slip/jump conditions in order to capture some of the physical processes involved in gas flow over a surface. These new conditions are validated for flat plate flow, circular cylinder in cross-flow, and the flow over a sharp wedge for Mach numbers ranging from 6 to 24, and for argon and nitrogen as the working gases. Our simulation results show that the new boundary conditions give better predictions for the surface pressures, compared with published experimental and DSMC data

Different landscape factors explain establishment and persistence of river red gum (Eucalyptus camaldulensis) in agricultural landscapes of southeast Queensland

Riparian and floodplain ecosystems in production landscapes are considerably degraded and under continued pressure from surrounding land use. However, little is known about how remnant ecosystems respond to land use and hydrological factors in small non-riverine wetlands. River red gum (Eucalyptus camaldulensis) is a dominant tree species within these scattered remnants, which provides critical ecological functions for the remaining biodiversity. In this study, we investigated how different life stages of E. camaldulensis responded to land use and hydrological variables in the Condamine catchment of south east Queensland. We used logistic regression to develop models for different life stages of E. camaldulensis in two regions with differing land use intensity histories. Broad regional differences and land use practices at smaller scales best explained differences in E. camaldulensis occurrence for younger life stages, while hydrology (groundwater and connectivity to rivers) and land use practices (dryland agriculture and grazing) best explained differences in older life stages. The results indicate that different factors are important in determining the establishment and persistence of E. camaldulensis and that land use practices at the regional scale are key factors in determining the establishment and potential future persistence of E. camaldulensis in floodplain wetlands

Delivering public services in the mixed economy of welfare : perspectives from the voluntary and community sector in rural England

The voluntary and community sector in England is playing an increasingly important role in the delivery of public services to older adults and in doing so they rely on unpaid volunteers. In this article, we draw on the findings of a recent qualitative study of the impact on the voluntary and community sector of delivering ‘low-level’ public services that promote independent living and wellbeing in old age. The fieldwork focused on services that help older adults aged 70+ living in remote rural communities across three English regions. Those charged with service delivery, which is increasingly the voluntary and community sector, face particular challenges, such as uncertain funding regimes and reliance on volunteer labour

New remarks on the Cosmological Argument

We present a formal analysis of the Cosmological Argument in its two main forms: that due to Aquinas, and the revised version of the Kalam Cosmological Argument more recently advocated by William Lane Craig. We formulate these two arguments in such a way that each conclusion follows in first-order logic from the corresponding assumptions. Our analysis shows that the conclusion which follows for Aquinas is considerably weaker than what his aims demand. With formalizations that are logically valid in hand, we reinterpret the natural language versions of the premises and conclusions in terms of concepts of causality consistent with (and used in) recent work in cosmology done by physicists. In brief: the Kalam argument commits the fallacy of equivocation in a way that seems beyond repair; two of the premises adopted by Aquinas seem dubious when the terms `cause' and `causality' are interpreted in the context of contemporary empirical science. Thus, while there are no problems with whether the conclusions follow logically from their assumptions, the Kalam argument is not viable, and the Aquinas argument does not imply a caused origination of the universe. The assumptions of the latter are at best less than obvious relative to recent work in the sciences. We conclude with mention of a new argument that makes some positive modifications to an alternative variation on Aquinas by Le Poidevin, which nonetheless seems rather weak.Comment: 12 pages, accepted for publication in International Journal for Philosophy of Religio

Analysis of the use and perception of shared mobility: A case study in Western Australia

The sharing economy has acquired a lot of media attention in recent years, and it has had a significant impact on the transport sector. This paper investigates the existing impact and potential of various forms of shared mobility, concentrating on the case study of Wanneroo, Western Australia. We adopted bibliometric analysis and visualization tools based on nearly 700 papers collected from the Scopus database to identify research clusters on shared mobility. Based on the clusters identified, we undertook a further content analysis to clarify the factors affecting the potential of different shared mobility modes. A specially designed questionnaire was applied for Wanneroo’s residents to explore their use of shared mobility, their future behaviour intentions, and their perspectives on the advantages and challenges of adoption. The empirical findings indicate that the majority of respondents who had used shared mobility options in the last 12 months belong to the low-mean-age group. The younger age group of participants also showed positive views on shared mobility and would consider using it in the future. Household size in terms of number of children did not make any impact on shared mobility options. Preference for shared mobility services is not related to income level. Bike sharing was less commonly used than the other forms of shared mobility

Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS)

We describe the design and performance of the SuMIRe Prime Focus Spectrograph (PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed ground-based spectrograph consisting of four identical spectrograph modules, each receiving roughly 600 fibers from a 2394 fiber robotic positioner at the prime focus. Each spectrograph module has three channels covering wavelength ranges 380~nm -- 640~nm, 640~nm -- 955~nm, and 955~nm -- 1.26~um, with the dispersed light being imaged in each channel by a f/1.07 vacuum Schmidt camera. The cameras are very large, having a clear aperture of 300~mm at the entrance window, and a mass of $\sim$280~kg. In this paper we describe the design of the visible camera cryostats and discuss various aspects of cryostat performance

Deviation Between δ13C and Leaf Intercellular Co2 in Salix Interior Cuttings Developing Under Low Light

This is the publisher's official version. It is also available electronically from: http://www.jstor.org/stable/10.1086/322892.Leaf δ13C values of perennial species are sometimes less negative than model‐predicted δ13C values derived from instantaneous measures of pi/pa. It has been hypothesized that the less negative δ13C values could be caused by 13C‐enriched stored carbon imported during the early stages of leaf growth. The δ13C values of newly emerging leaves could thus represent δ13C values of stem‐stored carbohydrates and may also provide integral measures of pi/pa at the end of the past growing season. We tested these hypotheses by sprouting cuttings of Salix interior under wet and dry soil‐moisture conditions in a controlled environmental chamber. Plants were defoliated after 56 d, and watering treatments were then reversed for half of the plants in each treatment. The δ13C values of newly emerging leaves did not correlate with pi/pa ratios of newly emerging leaves or of mature leaves prior to defoliation, thereby indicative that δ13C values of newly emerging leaves are not a simple reflection of prior pi/pa. Also, the δ13C values of newly emerging leaves were more enriched in 13C relative to the δ13C values of stem carbohydrates in the treatments where water regimes were reversed. Newly emerging leaves after defoliation had higher δ13C values despite the lower instantaneous water‐use efficiency and similar values of pi/pa to older photosynthetic leaves. Large differences between observed and model‐predicted pi/pa values also occurred in older, more mature leaves, and this may be because large proportions of their total mass were derived from carbon import

Lone mothers’ time allocations: Choices and satisfactions

This paper uses the 2006 Australian Time Use Survey to examine theallocation of time to personal care, employment-related activities, homeduties, leisure and child care of lone mothers, in comparison to the timeallocations of single women, women in childless couples and partneredmothers. Both primary and secondary time allocations are considered. Thesatisfactions that women report concerning their current time allocations arealso analysed. The time use and satisfaction data are described using bothtabulations and multiple regression methods. Lone mothers are shown tohave similar time allocations as the other types of households, even thoughthey have different financial and time resources. This raises the concernthat lone mothers’ desire or need to maintain such time allocations maylead to task overload. Consistent with this, lone mothers are found to beless satisfied with the way they allocate their time than single women andpartnered mothers. The tensions associated with time use among lonemothers discussed in the literature are real, and important