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991.
Leonard Champney 《Journal of the American Water Resources Association》1979,15(6):1602-1607
ABSTRACT: A general model of the policy implementation process is utilized to facilitate a discussion of the way Section 208 of PL 92-500 is being carried out on an areawide basis. A study of four “208 areas” in the “New York-Philadelphia corridor” highlights the operation of several variables used in the model. The varying political and socioeconomic conditions in geographic areas which have similar water quality problems are leading to the evolution of vastly different implementing structures, or institutional arrangements. The analysis suggests that these differences may have important implications for the success of the program in each of these areas. A major underlying theme is that such problems are characteristic of the 208 process nationwide and reflect general difficulties associated with managing water quality in a federal system. 相似文献
992.
An aspect of water resource development that has currently generated a good deal of interest among economists relates to the ‘economics of water transfer.’ Some recent investigations in this connection have studied the impact of transferring water from conventional uses (mainly agricultural) to newly emerging uses (e.g., pollution abatement, recreational, and industrial). The results of these studies indicate that water transfer contributes to economic growth, both directly and indirectly. 相似文献
993.
In this paper, we explore how scenarios of future water withdrawals in a river basin are influenced by scale-dependent quantifications of the driving forces for two global-scale storylines. Either global-scale information or region-specific information is used to do the quantifications. In addition, we analyze the impact of including or not some restricted regional-scale information in the employed water use model. To develop scenarios of water withdrawals in the German part of the Elbe River basin, we applied the modules for domestic, thermoelectric power and manufacturing water use of the global water model WaterGAP, using scale-dependent driving forces scenarios and other scale-dependent model input. In the global-scale quantitative interpretations of the storylines of the IPCC SRES scenarios A1 and B2, all major driving forces of water withdrawals in the basin—population, thermoelectric power production and industrial gross domestic product—show vigorous increases between 2000 and 2025, while from the regional perspective, smaller increases but mostly decreases appear to be plausible. These discrepancies are partly due to the fact that for the global-scale interpretations only the historic developments until 1990 were taken into account, and not until 2000 as in the regional case. The resulting scenarios of sectoral water withdrawals in 2025 differ strongly between the two scale-dependent interpretations of the storylines, with the global one leading to much higher absolute water withdrawals and much lower withdrawal decreases between 2000 and 2025. Therefore, for regional assessments of water withdrawals, we recommend to embed the scenario analysis in global-scale storylines by performing regional-scale quantifications of the global qualitative driving forces scenarios, based on a limited amount of region-specific information. 相似文献
994.
Effects of a tropical cyclone on the drinking-water quality of a remote Pacific island 总被引:2,自引:0,他引:2
The effect of a cyclone (Ami, January 2003) on drinking-water quality on the island of Vanua Levu, Fiji was investigated. Following the cyclone nearly three-quarters of the samples analysed did not conform to World Health Organisation (WHO) guideline values for safe drinking-water in terms of chlorine residual, total and faecal coliforms, and turbidity. Turbidity and total coliform levels significantly increased (up 56 and 62 per cent, respectively) from pre-cyclone levels, which was likely due to the large amounts of silt and debris entering water-supply sources during the cyclone. The utility found it difficult to maintain a reliable supply of treated water in the aftermath of the disaster. Communities were unaware they were drinking water that had not been adequately treated. Circumstances permitted this cyclone to be used as a case study to assess whether a simple paper-strip water-quality test (the hydrogen sulphide, H(2)S) kit could be distributed and used for community-based monitoring following such a disaster event to better protect public health. The H(2)S test results correlated well with faecal and total coliform results as found in previous studies. A small percentage of samples (about 10 per cent) tested positive for faecal and total coliforms but did not test positive in the H(2)S test. It was concluded that the H(2)S test would be well suited to wider use, especially in the absence of water-quality monitoring capabilities for outer island groups as it is inexpensive and easy to use, thus enabling communities and community health workers with minimal training to test their own water supplies without outside assistance. The importance of public education before and after natural disasters is also discussed. 相似文献
995.
关于中国的水安全问题及其对策探讨 总被引:20,自引:4,他引:16
随着全球性资源生态危机的加剧及全球化进程的飞速发展 ,国家安全要素扩大到包括资源环境在内的一些非传统安全要素上 ,现今 ,水安全已成为国家安全问题的核心内容之一。为此 ,笔者探讨了我国水安全存在的一些主要问题 ;分析了产生这些问题的原因 ;提供了解决这些问题的对策。 相似文献
996.
The effects of livestock grazing on selected riparian and stream attributes, water chemistry, and algal biomass were investigated
over a two-year period using livestock enclosures and by completing stream surveys in the Cypress Hills grassland plateau,
Alberta, Canada. Livestock enclosure experiments, partially replicated in three streams, comprised four treatments: (1) early
season livestock grazing (June–August), (2) late season livestock grazing (August–September), (3) all season grazing (June–September),
and (4) livestock absent controls. Livestock grazing significantly decreased streambank stability, biomass of riparian vegetation,
and the extent to which aquatic vegetation covered the stream channels compared with livestock-absent controls. Water quality
comparisons indicated significant differences among the four livestock grazing treatments in Battle and Graburn creeks but
not in Nine Mile Creek. In Graburn Creek, the concentration of total phosphorus in the all-season livestock grazing treatment
was significantly higher than that in the livestock-absent control, and the early season and late season grazing treatments.
Concentrations of soluble reactive phosphorus in the all-season livestock grazing treatment also exceeded that in livestock-absent
control. In contrast, differences in water quality variables in the remaining 22 comparisons (i.e., 22 of the total 24 comparisons)
were minor even when differences were statistically significant. Effects of livestock grazing on algal biomass were variable,
and there was no consistent pattern among creeks. At the watershed scale, spatial variation in algal biomass was related (P < 0.05) with concentrations of NO2
− + NO3
− and soluble reactive phosphorus in two of the four study creeks. Nutrient diffusing substrata experiments showed that algal
communities were either nitrogen-limited or not limited by nutrients, depending on stream and season. 相似文献
997.
Presently in Australia there are no mandatory drinking water standards. Here we argue that the risk associated with drinking
water in Australia is of a dimension discernible to warrant mandatory regulations. The catchments that supply the major metropolitan
areas of Sydney and Adelaide, and the groundwater for the city of Perth have been seriously compromised by the encroachment
of development and activities. Melbourne in the past has generally relied on a closed catchment reservoir system; however,
population growth in the near future will sequester the full online operation of additional reservoirs, which have multiple
land use catchments. In addition to the current landscape circumstances, the management of a water system in itself proposes
significant issues of risk. Two critical assumptions that are unique to a mass medium substance like water and dramatically
alter the appraisal of risk are: (1) very large numbers of people are potentially exposed, and (2) small changes in contaminant
levels may have adverse population outcomes. It is also known that water reticulation systems frequently suffer from contamination
problems caused solely by the distribution system, and optimal management of these facilities would best be served by statutory
protected transparency and dedicated water quality programs. In 1979, an Australian parliamentary committee stated that an
“uncontaminated water supply is” a “basic requirement for the obtainment of good health”; however, recent surveys of Australian
water systems show many are not meeting basic water quality criteria, and many communities are not receiving regular monitoring
or testing as required by government authorized Australian drinking water guidelines. Exacerbating this situation is the lack
of reporting and statutory endorsed standardized procedures to ensure information is properly and promptly recorded and that
data are centralized for maximum benefit. The evaluation of risk associated with drinking water in Australia is often hampered
by inadequate or incomplete data. Lastly, regional and rural water supplies face a vast array of contemporary problems and
experiences that include widespread usage of pesticides and agricultural chemicals. In recent years, the Darling River has
experienced the worst algal bloom known to man, and this river system not only supplies a number of regional and rural towns
with water, but eventually connects with the River Murray, which supplies the State of South Australia with approximately
50% of its water requirements. 相似文献
998.
Christopher P. Holt Paul S. Phillips Margaret P. Bates 《Resources, Conservation and Recycling》2000,30(4)
As a result of the UK Government's waste policy, which increasingly encourages sustainable development, and the realisation that water in the UK cannot be treated as an unlimited resource, there is growing interest in reducing the demand for water by industry. A series of industrial waste minimisation clubs have been set up within the country. This paper identifies the effectiveness of these clubs in reducing the demand for water. An overview of some of the clubs show how there is a major discrepancy between potential and implemented water savings, whilst a more detailed analysis of three specific examples show how water demand and cost to the company can be reduced, with the project paying for itself within around 1 year. It appears that companies are able to reduce water consumption by approximately 30%. If this level of saving was taken up by the entire industrial sector in England and Wales, water consumption could be reduced by approximately 1500 Ml/day. This reduction would be more significant in regions of lower rainfall, for example East Anglia and Southeast England. 相似文献
999.
Analysis of technological wastewater streams in a refinery and petrochemical complex was carried out. Wastewater flowrates, temperatures, pH and pollutant contents were measured. Regarding the characteristics of the individual waters, possible connections between water outflows from the processes or process units and potential water consumers were determined. Possibilities to reduce the flowrate of technological wastewater with wastewater reuse or preliminary regeneration and reuse were found. The consumption of fresh water could be lowered by 11.2 m3/h, reducing the treatment system load and prolonging its residence time by 7%. The payback period for the changes proposed in the petrochemical plants is 6 months with annual savings of US$27 630. The payback period for the changes proposed in the refinery is 11 days with annual savings of US$15 500. 相似文献
1000.
Comparative Analysis of New Zealand and US Approaches for Agricultural Nonpoint Source Pollution Management 总被引:1,自引:0,他引:1
Brian S. Caruso 《Environmental management》2000,25(1):9-22
The role of the central government in New Zealand is generally limited to research and policy development, and regional councils
are responsible for most monitoring and management of the problem. The role of the federal government in the United States
includes research and monitoring, policy development, and regulation. States also have a significant management role. Both
countries rely on voluntary approaches for NPS pollution management. Very few national water quality standards exist in New
Zealand, whereas standards are widely used in the United States. Loading estimates and modeling are often used in the United
States, but not in New Zealand. A wide range of best management practices (BMPs) are used in the United States, including
buffer strips and constructed/engineered wetlands. Buffer strips and riparian management have been emphasized and used widely
in New Zealand.
Many approaches are common to both countries, but management of the problem has only been partly successful. The primary barriers
are the inadequacy of the voluntary approach and the lack of scientific tools that are useful to decision-makers. More work
needs to be performed on the evaluation of approaches developed in both countries that could be applied in the other countries.
In addition, more cooperation and information/technology transfer between the two countries should be encouraged in the future. 相似文献