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991.
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
992.
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
993.
994.
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
995.
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
996.
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
997.
Emerging approaches to water resources development and management typically highlight equity and productivity as two main objectives. In the context of integrated water resources management within a river basin, managers and stakeholders often need a comparative assessment of different options for water augmentation and/or allocation. Pitting such options against predefined objectives, such as equity and productivity, requires an assessment of the effects that available options will have on these objectives. Available documentation indicates that not only does the interpretation of such objectives vary widely, but also the available methods for assessing equity and productivity run into significant limitations in the availability of adequate data. This limitation has largely kept decision makers from gaining a comprehensive overview of equity and productivity scenarios, whether within or across sectors, that could facilitate better‐informed decisions. To address this methodological gap, this article scrutinizes different notions associated with equity and water productivity, and limitations in prevalent assessment methods with the view to develop and demonstrate pragmatic methodologies for assessing equity and productivity in data‐scarce contexts. The discussion and findings are based on a review of relevant literature and empirical and consultative research work in the Olifants River basin in South Africa. The demonstrated methodologies for assessing equity and productivity, besides being useful in data‐scarce contexts, are insightful for initiating several policy measures and also for exploring the relationship between equity and water productivity. 相似文献
998.
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
999.
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
1000.
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