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311.
The National Water Commission (NWC) and the $2 billion Australian Government Water Fund (the fund) has drawn attention to the need for innovative and adaptive practices for water use. The NWC and the fund, whilst a critical and catalytic step in the recognition of the current water situation in Australia, has thus far neglected to consider the systemic failures of the water, irrigation and related industries that led to this point. The underlying issue of the efficient allocation of water resources can be resolved by the harmonisation of competing demands (economic, social and environmental) and the establishment of governance structures to reduce institutional impediments. The linking of the fund to National Competition Council (NCC) payments is an important consideration in this process. This paper will argue that governance reform and institutional (re)alignment to remedy the impediments to the efficient allocation of water resources needs to be embedded in and linked to national competition policy principles. This paper will consider the NWC in this context with the aim of informing future policy to consider the systemic failures of the water industry and to forge institutional change for the more effective allocation of water.  相似文献   
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Environmental Science and Pollution Research - COVID-19 pandemic waves hitting worldwide result in drastic postinfection complications with interindividual variations, which raised the question for...  相似文献   
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In July 2002, a multi-sensor campaign was conducted in southern France to investigate the hypothesized connection between gravity waves and optical turbulence. A generalized scidar (GS) was mounted on the 1.93 m diameter telescope at l’Observatoire de Haute-Provence (OHP). The GS provides continuous profiles of optical turbulence with 300 m vertical resolution from telescope altitude up to 25 km. Thermosondes, which provide in situ measurement of optical turbulence by measuring temperature variance, were launched at the OHP site and at a site approximately 20 km west-northwest of OHP. Gravity wave activity was deduced from temperature and wind velocity measured by radiosondes, which are part of the thermosonde system. In this paper, gravity waves were analyzed using techniques for simple two-dimensional mountain waves, with only fair results. Mesoscale models were run at moderately high resolution for the period. The forecasts were analyzed for wave activity, and a post processor model was used to diagnose the optical turbulence. Mountain waves were evident in the forecast, but quantitative comparison showed the forecast to be inadequate in predicting wave strength. The forecast optical turbulence was in fair agreement with measurements with notable exceptions. This paper is declared a work of the U.S. Government and is not subject to copyright protection in the United States. The U.S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. Presented at the Turbulence and Waves in Stably Stratified Atmospheric Shear Flows: Measurements, High Resolution Simulations and Numerical Prediction Challenges Conference, 13–15 September 2004, Lighthill Institute of Mathematical Sciences, University College London, London, UK.  相似文献   
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Abstract: Wildlife crossing structures are intended to increase permeability and habitat connectivity across roads. Few studies, however, have assessed the effectiveness of these mitigation measures in a multispecies or community level context. We used a null model to test whether wildlife crossing structures serve large mammal species equally or whether such structures limit habitat connectivity across roads in species-specific ways. We also modeled species responses to 14 variables related to underpass structure, landscape features, and human activity. Species performance ratios (observed crossing frequency to expected crossing frequency) were evaluated for four large carnivore and three ungulate species in 11 underpass structures in Banff National Park, Alberta, Canada. Observed crossing frequencies were collected in 35 months of underpass monitoring. Expected frequencies were developed from three independent models: radio telemetry, pellet counts, and habitat-suitability indices. The null model showed that species responded to underpasses differently. In the presence of human activity carnivores were less likely to use underpasses than were ungulates. Apart from human activity, carnivore performance ratios were better correlated to landscape variables, and ungulate performance ratios were better correlated to structural variables. We suggest that future underpasses designed around topography, habitat quality, and location will be minimally successful if human activity is not managed.  相似文献   
315.
In this paper we consider the special nature and implications, for economic theory and policy, of resource uses that involve adverse effects on the physical environment that are difficult or impossible to reverse. Distinctions are drawn between reversible and irreversible activities, between replaceable and irreplaceable resources. The existence of an “irreversibility premium” is demonstrated under certain plausible conditions, including uncertainty and shifting time perspective.  相似文献   
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Strips of Ca-I [polylactic acid (PLA) monolayer plastic films from Cargill Dow Polymers LLC, Minnetonka, MN] cut in the machine and nonmachine directions were irradiated with an electron beam using a CIRCLE III Linear Accelerator (MeV Industries S.A., Jouy-en-Josas, Cedex, France). The effects of 33-kGy irradiation on the physical properties of the Ca-I strips were studied. In addition, the effects of ultraviolet (UV) light (365-nm) illumination on the degradation of three PLA plastic films, Ch-I (PLA monolayer plastic films from Chronopol, Golden, CO), GII (PLA trilayer plastic films from Cargill Dow Polymers LLC), MN), and Ca-I (PLA monolayer plastic films from Cargill Dow Polymers LLC) were analyzed by a modified ASTM D5208-91 method. Results showed that irradiation had decreased the weight-average molecular weight (Mw), stress at break, percentage of elongation, and strain energy of Ca-I by 35.5, 26.7, 32.3, and 44.8%, respectively (P < 0.01). The shelf life of the irradiated Ca-I strips at 5°C and <20 ± 5% RH was about 6 months. The degradation rate of Ch-I, GII, and Ca-I with no UV light treatment at 55°C and 10% RH was 2512, 5618, and 3785 Mw/week, respectively. Under the UV light illumination (365 nm), the degradation rate of Ch-I, GII, and Ca-I, was 2982, 8722, and 7467 Mw/week, respectively. Hence, the degradation rate of GII and Ca-I was increased 55 and 97% by UV light (P < 0.008), respectively. This trend was not observed in Ch-I because its starting Mw (78,000 g/mol) was close to the tensile strength lost range (50,000 to 75,000 g/mol) of PLA films. To our knowledge, this is the first study to demonstrate that UV light does further enhance the degradation of PLA films.  相似文献   
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