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941.
The Water Poverty Index: Development and application at the community scale   总被引:17,自引:1,他引:17  
The article details the development and uses of the water poverty index (WPI). The index was developed as a holistic tool to measure water stress at the household and community levels, designed to aid national decision makers, at community and central government level, as well as donor agencies, to determine priority needs for interventions in the water sector. The index combines into a single number a cluster of data directly and indirectly relevant to water stress. Subcomponents of the index include measures of: access to water; water quantity, quality and variability; water uses (domestic, food, productive purposes); capacity for water management; and environmental aspects.
The WPI methodology was developed through pilot projects in South Africa, Tanzania and Sri Lanka and involved intensive participation and consultation with all stakeholders, including water users, politicians, water sector professionals, aid agency personnel and others. The article discusses approaches for the further implementation of the water poverty index, including the possibilities of acquiring the necessary data through existing national surveys or by establishing interdisciplinary water modules in school curricula. The article argues that the WPI fills the need for a simple, open and transparent tool, one that will appeal to politicians and decision makers, and at the same time can empower poor people to participate in the better targeting of water sector interventions and development budgets in general.  相似文献   
942.
This paper provides non-hazardous solid waste audit procedures and bench mark audit data for golf courses (GCs). The paper also demonstrates the narrow scope of solid waste audit data, and the need to move towards a broader auditing scope such as that contained in sustainability auditing frameworks. A case study of Clear Lake Golf Course, located in southwestern Manitoba, Canada was completed. Annual waste generation rates at the GC were estimated to be 46.2 tonnes/year with 83% of this material compostable. Grass clipping material generated from the putting greens accounted for 79% of the waste stream. The GC achieved a solid waste diversion rate of 81% (waste generated not destined for landfill per total waste material generated). A future, realistic target of 97% diversion was also identified. The 7 day audit period was found to be unsuitable for estimating grass clipping generation rates. Implementation of a broader sustainability framework for future audits will harmonize many existing management functions such as solid waste auditing, waste characterizations, pollution prevention, green procurement, customer satisfaction, and the efficiency of the operations.  相似文献   
943.
ABSTRACT: The time to hydrograph peak of a watershed basin has been found to correlate with various statistical attributes (e.g., skewness and kurtosis) of its hypsometric curve (treated as probability distribution). This paper presents a theoretical travel time that is conceptually analogous to the time to hydrograph peak and can be calculated directly from the hypsometric curve of a watershed basin based on gravity and acceleration. The theoretical travel times for 23 selected watersheds in the United States are found to correlate significantly with their corresponding hypsometric attributes. In addition, the theoretical travel times are consistent with the times of concentration estimated from the Federal Aviation Administration method. Thus, this paper offers a simple theoretical explanation to the empirically identified linkage between time to hydrograph peak and hypsometric attributes. This theoretical travel time can provide an alternative way of characterizing the effects of basin morphometry on hydrologic response.  相似文献   
944.
ABSTRACT: This paper presents the results of a study on the use of continuous stage data to describe the relation between urban development and three aspects of hydrologic condition that are thought to influence stream ecosystems—overall stage variability, stream flashiness, and the duration of extreme‐stage conditions. This relation is examined using data from more than 70 watersheds in three contrasting environmental settings—the humid Northeast (the metropolitan Boston, Massachusetts, area); the very humid Southeast (the metropolitan Birmingham, Alabama, area); and the semiarid West (the metropolitan Salt Lake City, Utah, area). Results from the Birmingham and Boston studies provide evidence linking increased urbanization with stream flashiness. Fragmentation of developed land cover patches appears to ameliorate the effects of urbanization on overall variability and flashiness. There was less success in relating urbanization and streamflow conditions in the Salt Lake City study. A related investigation of six North Carolina sites with long term discharge and stage data indicated that hydrologic condition metrics developed using continuous stage data are comparable to flow based metrics, particularly for stream flashiness measures.  相似文献   
945.
946.
ABSTRACT: The use of watersheds to conduct research on land/water relationships has expanded recently to include both extrapolation and reporting of water resource information and ecosystem management. More often than not, hydrologic units (HUs) are used for these purposes, with the implication that hydrologic units are synonymous with watersheds. Whereas true topographic watersheds are areas within which apparent surface water drains to a particular point, generally only 45 percent of all hydrologic units, regardless of their hierarchical level, meet this definition. Because the area contributing to the downstream point in many hydrologic units extends far beyond the unit boundaries, use of the hydrologic unit framework to show regional and national patterns of water quality and other environmental resources can result in incorrect and misleading illustrations. In this paper, the implications of this misuse are demonstrated using four adjacent HUs in central Texas. A more effective way of showing regional patterns in environmental resources is by using data from true watersheds representative of different ecological regions containing particular mosaics of geographical characteristics affecting differences in ecosystems and water quality.  相似文献   
947.
948.
 The effect of the soil solids concentration in batch tests on the measured values of the partition coefficient (K p) of organic pollutants in landfill liner-soil material was investigated. Since this study was based on the results of batch and column tests conducted independently, there were limitations to the conclusions derived. The organic compounds tested were benzene, methylene chloride, toluene, trichloroethylene, and p-xylene. The results of this study showed that as soil solids concentrations increased, the measured K p values of these organic compounds strongly decreased. The observed values of K p stabilized when the soil solids concentration was above a certain value. Typical K p values obtained from batch tests conducted under high soil solids concentrations were close to those obtained from column tests. It was concluded that the K p values of organic compounds measured under low soil solids concentrations, i.e., less than 100 g/l, may not correctly simulate the field situation. Consequently, the values of K p obtained with low soil solids concentrations can result in an overestimation of the retardation factor of the landfill liner material. Received: March 14, 2002 / Accepted: August 25, 2002  相似文献   
949.
At the district heating plant of Kalmar, Sweden an on-line unit for production of granulated wood ash for nutrient recycling on forest soils is being applied. Currently, the granules are dried by hot air from an oil-fired burner. The objective of this work was to investigate how drying by flue gas affects the hardening of granules, or impacts their chemical composition and properties. Ninety-six granule samples were treated by flue gas from natural gas combustion in a laboratory pilot scale flue gas generator. CO2, CO, O2, C3H8 and NO concentrations were varied during the experiment. Additionally, some samples were treated by flue gas from combustion of sawdust at the heating plant in Kalmar. Drying by flue gases did not affect the chemical composition of granules, but minor effects were seen in their mineralogy. The carbonate content was slightly higher in granules treated with flue gas from natural gas combustion compared to the granules dried by hot air only, when measured by wet chemical methods. Results from XRD analysis imply that the calcite content is higher and the portlandite and arcanite content slightly less in granules treated with flue gas from sawdust combustion compared to the granules dried by hot air only. The results from this investigation showed no negative effects on ash granule composition or physical structure by the use of a flue as a drying medium.  相似文献   
950.
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