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991.
本文以大量事实论述了上海市由于水质污染,不仅严重威胁着上海市民的身体健康,而且已导致上海市严峻的水荒灾害问题。文章还从历史回顾中论证了上海市在治理水质污染方面的失策,并根据国内外的经验教训,提出了解决上海市水荒同题的对策和建议。 相似文献
992.
Analysis of a rural water supply project in three communities in Mali: Participation and sustainability 总被引:1,自引:0,他引:1
This paper presents a qualitative assessment of the participatory water management strategies implemented at the community level in rural Mali through a water supply project — The West Africa Water Initiative (WAWI) — coordinated by World Vision International, a non‐governmental and humanitarian organization. Data for the study were generated through a combination of primary and secondary sources in three villages. Results of the study indicate that while community‐based rural water supply is a positive step in responding to the needs of rural Malians, the installation of boreholes with hand pumps informed merely by consultative participatory approaches and limited extension involvement will not necessarily proffer sustainable rural water supply in the region. A “platform” approach to rural water supply management that can mobilize the assets and insights of different social actors to influence decision making at all stages, including the design and choice‐of‐technology stages, in water supply interventions is instead advocated. 相似文献
993.
Key aspects of environmental management exist within a legislative framework. The Rivers and Foreshores Improvement Act 1948 (NSW) and several Regional Environmental Plans created under the Environmental Planning and Assessment Act 1979 (NSW) make reference to ‘the top of the bank’ for defining areas of protected land adjacent to rivers, within which development
consent may be required. It is an arbitrary term and its use within the Rivers and Foreshores Improvement Act 1948 (NSW) leads to confusion. This paper examines the range of definitions of ‘the top of the bank’ in respect of natural watercourses
and aims to provide a more lucid and effective definition that will clarify existing ambiguities in legal interpretation.
The paper examines the historical origins of the phrase ‘top of the bank’, finding that stereotyped Eurocentric views of what
a river ‘should look like’ have impaired the legal definition for Australian rivers, thereby influencing common law and the
development of statutory definitions. Judicial applications of the phrase ‘top of the bank’ are examined from a geomorphological
perspective, demonstrating the misconceptions of the term in a legal context. The paper identifies the existence of widespread
support for the need to protect land adjacent to rivers in the interests of environmental, economic and social sustainability.
It concludes by calling for legislative reform that is both tailored to the individual site and consistent with overarching
goals at the catchment scale. 相似文献
994.
Tirusew Asefa Nisai Wanakule Alison Adams 《Journal of the American Water Resources Association》2007,43(5):1245-1256
Abstract: In this paper, a field‐scale applicability of three forms of artificial neural network algorithms in forecasting short‐term ground‐water levels at specific control points is presented. These algorithms are the feed‐forward back propagation (FFBP), radial basis networks (RBN), and generalized regression networks (GRN). Ground‐water level predictions from these algorithms are in turn to be used in an Optimized Regional Operations Plan that prescribes scheduled wellfield production for the coming four weeks. These models are up against each other for their accuracy of ground‐water level predictions on lead times ranging from a week to four weeks, ease of implementation, and execution times (mainly training time). In total, 208 networks of each of the three algorithms were developed for the study. It is shown that although learning algorithms have emerged as a viable solution at field scale much larger than previously studied, no single algorithm performs consistently better than others on all the criteria. On average, FFBP networks are 20 and 26%, respectively, more accurate than RBN and GRN in forecasting one week ahead water levels and this advantage drops to 5 and 9% accuracy in forecasting four weeks ahead water levels, whereas GRN posted a training time that is only 5% of the training time taken by that of FFBP networks. This may suggest that in field‐scale applications one may have to trade between the type of algorithm to be used and the degree to which a given objective is honored. 相似文献
995.
Over-allocation of irrigation water has led to widespread environmental degradation in the Murray-Darling Basin (MDB) in Australia,
prompting discussions of the water efficiency performance of irrigated industries. There is increasing pressure for irrigators
to adopt water efficient practices in line with ecologically sustainable principles, especially with current drought conditions.
However, there is great uncertainty surrounding the available practices to improve irrigation efficiency from both ecological
and economic standpoints. This paper examines the economic and environmental impact of several possible water efficient practices
and government policies, using an interdisciplinary approach combining biophysical modelling and economic modelling. This
is done for the case-study of the Mooki catchment in the MDB, located in northern New South Wales, Australia. 相似文献
996.
The biological removal of phosphates was carried as a part of treatment strategy. Vetiveria zizanioides (L.) Nash belonging to the family Poaceae was used for biological removal of biostimulants. Vetiver reportedly has mycorrhizal
association; besides having potential for removal of PO4
−3 also showed allelopathic affect on the microorganisms present in the water. In fact after a period of 96 h old roots of this
plant have been found to have killing effects on the E. coli, Enterobacter spp. Pseudomonas spp. belonging to the family Enterobacteriaceae. The paper is opening a new face of study. 相似文献
997.
998.
It is difficult to make general recommendations that apply to all ecosystems. There is still a relative dearth of studies
that allow the manager or visitor to come up with specific practices that are the best for their area. The preferred method
of disposal remains to dig a small hole (cat hole) and bury the waste. Other site specific methods are also discussed.
Treatment of drinking water has become standard practice for most backcountry travel. With such treatment, there is little
evidence currently to suggest that the health hazard to humans is great enough to impose further regulation in areas currently
using cat holes. 相似文献
999.
Minimal models and agroecological policy at the regional scale: An application to salinity problems in southeastern Australia 总被引:2,自引:0,他引:2
John M. Anderies 《Regional Environmental Change》2005,5(1):1-17
A minimal dynamical systems model that couples agricultural activity, native vegetation, and hydrological processes is developed to explore policy options regarding regional-scale soil and water salinization in southeastern Australia. The analysis suggests that although considerable revegetation is required to restore catchment water balance, the current value of water in uses other than agriculture is too low for revegetation to be economically viable. In contrast, groundwater pumping generates significant short-term gains by preventing soil salinization but is not a viable long-term solution. Thus, effective salinity management policy must include mechanisms to increase the value of water in uses other than irrigated agriculture to achieve sufficient long-term revegetation. These results are robust over a wide range of parameter values and thus provide a basis for policy action in the face of uncertainty about groundwater flow characteristics. 相似文献
1000.
Application of a Physical Input–Output Table to Evaluate the Development and Sustainability of Continental Water Resources in Spain 总被引:1,自引:0,他引:1
Continental waters are complex resources in terms of a measurable physical quantity, and measuring them requires a good knowledge of total water availability. In this research, an accounting physical input–output table (PIOT) was applied to evaluate total water resources and gross annual availabilities at each stage of the natural-artificial water cycle. These stages are considered subsystems of a continental water resource system describing water transfers for an average year within 13 administrative basins of Spain. Water transfers between various subsystems are characterized by internal flows decreasing the water resource availabilities. The PIOT analysis establishes these internal flows, and the origins and final uses of the total resources for each subsystem. The input-output balance registered an unsustainable negative net accumulation in eight water basins. The PIOT analysis also allowed the calculation of significant indicators such as water resource developments (RDI) and their sustainable use (SUI). RDI and SUI demonstrate that groundwater is a critical resource affecting the environment (e.g., wetlands in the upper Guadiana) and the water supply (e.g., irrigation in the Segura basin). The results of this model suggest that above-/below-ground hydrological links are important when decisions have to be made in order to provide a satisfactory supply of water in Spain. The model integrates the different water basins under territorial criteria, and therefore it may be useful for the Spanish National Hydrological Plan. 相似文献