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321.
Climate change risks to the coast and coastal developments have been well-documented. In spite of these warnings, new coastal developments are still proposed and built. Australian research has demonstrated how State-level planning documents fail to incorporate recent sea-level rise projections, with researchers demanding more responsiveness to coastal science from planners, policy-makers and developers. This paper takes an alternative approach to the science, planning and coastal development nexus by developing a relational understanding of the barriers to the uptake of science into coastal development decisions. Drawing on qualitative interview material from two recent and non-routine South Australian cases where sea-level rise (SLR) science was contested, and inspiration from actor-network theory's concepts of obligatory passage points, translation, intermediaries and mediators, this research foregrounds the malleability of scientific knowledge and planning protocols. We find that skilful social actors negotiate and re-frame science and planning; clear scientific recommendations can be subsumed to planning process, while clear planning process creates internecine disputes between nomothetic and idiographic science. An implication of this analysis is that the broad narrative of a lack of scientific uptake into coastal development needs to be sensitized to how science and planning interact in practice to legitimate decisions.  相似文献   
322.
In certain environments nutrient and energy sources available to microorganisms can be limited. Foodborne pathogens must efficiently adapt in order to be successfully transmitted through the food chain to their hosts. For the intracellular foodborne pathogen Listeria monocytogenes, little is known regarding its response to nutrient/energy-limiting conditions. The alternative stress responsive sigma factor σB has been reported to contribute to survival under specific stresses. Therefore, the effects of several metabolic inhibitors on growth of L. monocytogenes wild-type and a ΔsigB mutant were examined. In the absence of inhibitors, both strains reached stationary phase after 18 h at 23°C and 10 h at 37°C. All of the metabolic inhibitors slowed growth of either strain, with few differences observed among the different inhibitors.  相似文献   
323.
Results of a series of nighttime tracer experiments conducted during the Autumn of 1966 in the industrialized valley of Johnstown, Pa., are discussed. Quite atypical meteorology and dispersion occur within a classical drainage flow framework. An urban heat island effect is observed creating uniform temperature and wind structures within a layer of air flowing through the valley. Dispersion in the valley at night is comparable to that of neutral conditions over open country.  相似文献   
324.
This paper describes the development of a methodology to theoretically assess the stormwater pollutant removal performances of structural best management practices (BMPs). The method combines the categorisation of the relative importance of the primary removal processes within 15 different BMPs with an evaluation of the ability of each process to remove a pollutant in order to generate a value representing the pollutant removal potential for each BMP. The methodology is demonstrated by applying it separately to a set of general water quality indicators (total suspended solids, biochemical and chemical oxygen demand, nitrates, phosphates and faecal coliforms) to produce a ranked list of BMP pollutant removal efficiencies. Given the limited amount of available monitoring data relating to the differential pollutant removal capabilities of BMPs, the resulting prioritization will support stakeholders in making urban drainage decisions from the perspective of pollutant removal. It can also provide inputs to existing urban hydrology models, which aim to predict the treatment performances of BMPs. The level of resilience of the proposed approach is tested using a sensitivity analysis and the limitations in terms of BMP design and application are discussed.  相似文献   
325.
On-ground natural resource management actions such as revegetation and remnant vegetation management can simultaneously affect multiple objectives including land, water and biodiversity resources. Hence, planning for the sustainable management of natural resources requires consideration of these multiple objectives. However, planning the location of management actions in the landscape often treats these objectives individually to reduce the process and spatial complexity inherent in human-modified and natural landscapes. This can be inefficient and potentially counterproductive given the linkages and trade-offs involved. We develop and apply a systematic regional planning approach to identify geographic priorities for on-ground natural resource management actions that most cost-effectively meet multiple natural resource management objectives. Our systematic regional planning approach utilises integer programming within a structured multi-criteria decision analysis framework. Intelligent siting can capitalise on the multiple benefits of on-ground actions and achieve natural resource management objectives more efficiently. The focus of this study is the human-modified landscape of the River Murray, South Australia. However, the methodology and analyses presented here can be adapted to other regions requiring more efficient and integrated planning for the management of natural resources.  相似文献   
326.
There has been a large increase in private sector participation (PSP) in the urban water supply and sanitation (WSS) sector in recent years. However, even with increased PSP, public authorities will still have to: ensure that the service providers do not use their market power to exploit customers; internalise public health and environmental externalities; provide mechanisms whereby water consumption is sustainable and allocated efficiently between alternative uses; and stand as a guarantor of a level of service provision that is consistent with a basic standard of living. While there is considerable literature addressing the first of these four issues, the latter three are rather less adequately addressed. Through a review of a number of case studies (Abidjan, Buenos Aires/Cordoba, Mexico City and Manila), this paper provides an overview of the issues involved and some of the mechanisms available to the authorities responsible for the regulation of the sector.  相似文献   
327.
Rapid bioassessment (RBA) techniques for evaluating river health are now commonplace and there is much debate on the best methods that should be used. One of the important features of RBA is subsampling of large qualitative or semi-quantitative samples to reduce the costs associated with handling and identifying animals. In Australia, the Australian River Assessment System (known as “AusRivAS”) has been widely used since 1994 to monitor and assess river health. To test the efficacy of AusRivAS protocols, four live-sorting protocols, the standard Australian River Assessment Scheme (AusRivAS) and three suggested improvements, were evaluated in three habitat types and in clear and turbid rivers. The suggested improvements included using magnification during the live-sort process, separate sorting of coarse and fine fractions and increasing the amount of time or animals collected. There was no statistically significant difference between any of the trialed live-sort protocols in terms of the number of taxa collected compared to the number remaining, the community composition, the abundances of individual families collected, or the AusRivAS Observed/Expected taxa ratios. The lack of differences between the live-sort protocols suggests that technicians using the current standard AusRivAS protocols are able to effectively obtain a representative subsample of animals from the whole kick or sweep net qualitative sample. This has the advantage of cost savings because no retraining will be required, field procedures will remain uncomplicated and previous river health assessments will remain valid.  相似文献   
328.
Two different experimental techniques employing conservative tracers to determine exfiltration losses in a sewer system are reported. Both techniques compare the in-sewer responses measured along designated indicator and reference sections to assess the level of exfiltration although with different degrees of reliability. The experimental and interpretation errors associated with a pulse dosing technique, in which Rhodamine WT is used as the single tracer, are described. The estimation of exfiltration requires the comparison of indicator and reference peaks which need to be well resolved and reproducible in order to provide realistic results. A more consistent technique involves the continuous dosing of two different tracers with the objective of producing simultaneous downstream peak tracer concentrations. Any errors due to flow variations are eliminated and the longer measurement period allows both peak and background concentrations to be more accurately determined. Rhodamine WT, Li and Br were used in different combinations over the approximately 20 min duration of each continuous dosing experiment and were found to demonstrate conservative behaviours with measured recoveries of 97.6-100.6%, 97.3-101.4% and 108.4-109.2%, respectively. The analytical problems associated with the determination of the different tracers in sewage are described and are shown to be responsible for the reduced accuracy of the results associated with the use of Br. The preferred combination of tracers is Rhodamine WT as the indicator and Li as the reference and these are shown to be capable of estimating sewer losses to an accuracy of +/-1.0% using the continuous dosing approach.  相似文献   
329.
The Water Framework Directive is a major regulatory reform of water resources management within the European Union. Integrated catchment management plans must be prepared for all river basins, in order to achieve 'good ecological status' in all EU waters. Ecological status is a broader measure of water quality than the chemical and biological measures that were previously dominant. The Directive calls for a consideration of the economic costs and benefits of improvements to ecological status. In this paper, we use the choice experiment method to estimate the value of improvements in three components of ecological status. Given the high resource cost of valuation studies, benefits transfer methods will be needed in implementing the Directive. We thus also test the ability of choice experiments for benefits transfer across two very similar rivers in the UK.  相似文献   
330.
ABSTRACT: ArcView Nonpoint Source Pollution Modeling (AVNPSM), an interface between ArcView GIS and AGNPS (Agricultural Nonpoint Source Pollution Model) is developed in support of agricultural watershed analysis and nonpoint source pollution management. The interface is PC‐based and operates in a Windows environment. It consists of seven modules: AGNPS utility, parameter generator, input file processor, model executor, output visualizer, statistical analyzer, and land use simulator. Basic input data to the interface include: soil, digital elevation model, land use/cover, water features, climate, and information on management practices. Application of the AVNPSM to a sample watershed indicates that it is user friendly, flexible, and robust, and it significantly improves the efficiency of the nonpoint source pollution modeling process.  相似文献   
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