首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
ABSTRACT

This paper deals with the analytical issues involved in developing and using practical measures of equity for irrigation project performance evaluation. Deriving from the economic literature on equity in income distribution, the paper discusses the usefulness of seven different axioms for equity measures in evaluating the robustness of seven different positive measures of equity such as the range, the relative mean deviation, the variance, the coefficient of variation, the standard deviation of logarithms, the Gini coefficient and Theil's information measure. Based on the fulfillment/non-fulfillment of different axioms, the paper discusses the relative merits/demerits of the above-mentioned seven different measures and concludes on the basis of this critical evaluation that Theil's information measure is more useful than the rest since it fulfills many of the important axioms in addition to its being amenable for decomposition analysis.  相似文献   

2.
Management of water resources is a very challenging issue, particularly in regions of the world where water is almost absent. In the Gulf Region, this issue is especially complex due to harsh-arid environments and increasing anthropogenic input of pollutants from the energy industry. The emergence of nations rich in oil and gas, such as Qatar, but poor in water resources requires new and dynamic systems and plans for managing limited water resources in times of extreme growth, such plans are discussed in this paper. The State of Qatar’s average annual evaporation rate is 30 times more than precipitation and the country depends on desalinated water to meet 99 % of its municipal water needs. Additionally, increasing population growth coupled with tremendous urbanization and industrialization add more stress to the existing renewable water resources, and newly produced water, namely desalted seawater and treated wastewater. Absence of water tariff and a water pricing system along with a lack of conservation awareness places Qatar as one of the highest water consuming countries in the world. Municipal water consumption per capita per day reached 500 L/ca.d for the year 2013. Dumping of sea to build new cities and construct towers makes the area very susceptible to salt water instruction, a phenomenon that does not only affect the groundwater aquifer system but also the construction materials and building deformations. Currently, Qatar uses the most advanced technologies for treating wastewater; however, the pure treated wastewater is not considered a viable water resource and is not used in areas of critical water demand such as agriculture and landscaping. Social, religious, and local marketing views limit the current use of treated wastewater. Integrated water and wastewater management strategies are absent and the national players of the two sectors -water and wastewater-are different. Current plans for integrated water resources management (IWRM) cannot answer the basic questions, what to manage and in which scale; is it the brackish and unused groundwater or the desalinated water from the existing technologies, the supply or the demand or all? This paper tries to highlight some facts related to Qatar’s water situation as an arid Gulf State and introduces potential ideas for IWRM. The critical aspects of IWRM discussed herein are relevant to a number of nations in the global community dealing with issues of extreme water insecurity.  相似文献   

3.
Abstract

The River Commission of the Ministry of Construction in Japan recommended a basin response to floods in its December 2000 Interim Report to Minister of Construction. This is practically an official declaration of the policy accepting inundation in habited areas. By this policy shift, it is anticipated that more basin response measures and non-structural measures against floods will be promoted to complement structural measures such as continuous levees and dams. Such a policy is not new in the world but is a significant governmental move in Japan, a densely populated, highly developed, and highly flood hazardous country. Although living with floods is a universal coping strategy, the implementation of measures should be different from region to region reflecting region's nature and socio-economic conditions. This paper reviews the flood fighting history of Japan and her statutory evolution against floods and shows the process by which the ever-increasing flood damage potential and the recent increase of flood damages necessitated the official move in flood control management from rivers to basins.  相似文献   

4.
5.
6.
Viktor Dukhovny 《国际水》2013,38(4):530-531
Abstract

A hydrogeological and microbiological study was carried out in Italy in order to verify the effectiveness of a DRASTIC-based method for groundwater vulnerability assessment in carbonate (fractured-karstified) aquifers. The research was developed: (a) by the monitoring of microbial contamination of two springs from January to July 2001 and from December 2002 to March 2003; and (b) by column tests in intact soil blocks, utilizing a collection strain of Enterococcus faecalis. The comparison of the vulnerability map with the results of the microbiological experiments demonstrated the effectiveness of the new DRASTIC-based method as a predictor of groundwater microbial contamination in carbonate aquifers. The effectiveness of the new proposed approach was verified and highlights the diversified role of the diffuse infiltration of precipitations through the fracture pattern and the more or less concentrated infiltration of surface water in karst areas.  相似文献   

7.
Water resources allocation in a river basin is customarily determined based on long-term mean water availability. However, inter-annual variability of water resources caused by climate fluctuation should also be considered in order to keep an effective and flexible allocation policy. This paper analyzes the historical evolution of the water resources allocation system in the Yellow River basin of China. Based on the concept of water use flexible limit to water shortage and actual water use data from 1988–2006, a set of flexible limits to water shortage adapted to the Yellow River basin has been proposed. This includes total water use flexible limit to water shortage for all provinces, which is approximately 70%; and the different water use flexible limits to water shortage for each social sector, which are approximately 90% for agriculture, 85% for domestic use, and 50% for other industries. It offers a simple, yet effective, method for future water resources allocation in the Yellow River basin to achieve the optimal use of water resources. It likewise provides a beneficial reference for water resources management in the water deficient regions of China.  相似文献   

8.
Water Resources Management - In the context of climate stress, urbanisation and population growth, design and planning tools that assist in decentralised and environmental infrastructural planning...  相似文献   

9.
The Piracicaba, Capivari, and Jundiaí River Basins (RB-PCJ) are mainly located in the State of São Paulo, Brazil. Using a dynamics systems simulation model (WRM-PCJ) to assess water resources sustainability, five 50-year simulations were run. WRM-PCJ was developed as a tool to aid decision and policy makers on the RB-PCJ Watershed Committee. The model has 254 variables. The model was calibrated and validated using available information from the 80s. Falkenmark Water Stress Index went from 1,403 m3 person???1 year???1 in 2004 to 734 m3 P???1 year???1 in 2054, and Xu Sustainability Index from 0.44 to 0.20. In 2004, the Keller River Basin Development Phase was Conservation, and by 2054 was Augmentation. The three criteria used to evaluate water resources showed that the watershed is at crucial water resources management turning point. The WRM-PCJ performed well, and it proved to be an excellent tool for decision and policy makers at RB-PCJ.  相似文献   

10.
Abstract

Water scarcity in Jordan is a significant constraint to development, with limited available water and financial resources. As population and economic activity increase, it will be necessary to implement national strategies that seek to balance the present needs and those of future generations. Multiple variables associated with agricultural crops, industries, and the impact of climate change, were incorporated into a Decision Support System (DSS). The DSS utilized Analytical Hierarchy Process (AHP), which resulted in the prioritization of sustainable water policies for management in the Azraq Basin. The inputs to the DSS were generated through application of Modflow (groundwater), stochastic, and Penman Montieth models and through calculations of water productivity for agricultural and industrial sectors. The results of the DSS make recommendations as to how to enhance long-term sustainability of water resources in Azraq, while allowing for water utilization and economic growth. It is recommended for future planning that further research of the impacts to water resources must be conducted at local and national levels and linked to regional and global climate change prediction. It can be concluded that the DSS tool and AHP are potentially positive contributions to the process of decision- making for selection and ranking of alternatives and policies and for help in solving problems that include conflicting criteria.  相似文献   

11.
ABSTRACT

The paper describes the principal natural and structural characteristics of the Great Lakes system of North America, the world's largest inland waterway. Fluctuations in lakes levels have been one of the natural conditions of the lakes throughout their history, and, as development of the region has occurred, have caused significant water management problems. The paper examines some of the human responses to these problems, pointing out the difficulties in controlling lake levels on such an hydraulically complex system. It concludes that human adaptation to the system, as opposed to structural modification, holds the key to coping with the problems associated with fluctuating lake levels.  相似文献   

12.
13.
Water Resources Management - Reanalysis and earth observation data have enormous potential to support water resources management, particularly in river basins where data availability is poor or...  相似文献   

14.
Large tributary inflows into water supply reservoirs caused by heavy catchment rain may be of concern due to problems associated with high levels of natural organic matter (NOM) present in the inflows. The movement of these inflows within a reservoir is dependent on its relative density to the receiving waters. For example, if the inflow is denser (colder) than the recipient water it will travel along the base of the reservoir as an underflow and can penetrate as far as the dam wall water off-take to a water treatment plant (WTP). Field studies were conducted to track the passage of underflows through two South Australian reservoirs, Little Para and Myponga. Samples were collected before and during storm event inflows and analyses undertaken to determine NOM concentration, alum demand, disinfection by-product formation potential, and quality of the water. We demonstrate that by monitoring the movement of inflows into reservoirs, combined with changes in reservoir off-take levels, that the risk of NOM entering a water treatment plant can be reduced which in turn will lower water treatment costs by reducing alum dosing levels and lessen the risk to human health by reducing disinfection by-product formation.  相似文献   

15.
Following some definitions of IWRM within a context of integrated catchment management, and a summary of the major goals and strategies as well as scale considerations in IWRM, this paper highlights some differences between IWRM in Lesser Developed Countries (LDCs), i.e. the so-called “South”, and Developed Countries (DCs), i.e. the so-called “North”, by outlining characteristics of DCs and LDCs which shape their respective needs in IWRM. Thereafter inherent problems in regard to IWRM in LDCs are identified. This is followed by examples from four case studies in southern African catchments which focus on some of the uniquenesses of IWRM issues in LDCs which, in the author's experiences, are often forgotten by theorists and practitioners from the “North”,viz.that
•  while catchment studies tend to emphasise mainstem river discharge characteristics,these are not the sources of rural water supply problems in LDCs (a case study from the Thukela HELP catchment in South Africa);
•  water poverty is acute in many meso-scale catchments and is likely to be exacerbated by global warming (again, a case study from the Thukela catchment);
•  water quality problems for the rural poor, who are still without potable water supplies, frequently revolve around the biological health of rivers, rather than those related to chemical or physical water quality (a case study from the Mgeni catchment in South Africa); and
•  climate change may have severe impacts on both within-country reservoir management and out-of-country outflow obligations to downstream countries on already stressed catchments dominated by high water demanding irrigated crops (a case study from theMbuluzi catchment in Swaziland).
In each case study simulation modelling has been used as a tool in IWRM. A concluding section therefore focuses on some selected problems which have been identified by the author in regard to hydrological modelling in LDCs. These revolve around issues of governance, human resources and practicalities.  相似文献   

16.
17.
This study investigates an interdisciplinary scenario analysis to assess the potential impacts of climate, land use/cover and population changes on future water availability and demand in the Srepok River basin, a trans-boundary basin. Based on the output from a high-resolution Regional Climate Model (ECHAM 4, Scenarios A2 and B2) developed by the Southeast Asia—System for Analysis, Research and Training (SEA-START) Regional Center, future rainfall was downscaled to the study area and bias correction was carried out to generate the daily rainfall series. Land use/cover change was quantified using a GIS-based logistic regression approach and future population was projected from the historical data. These changes, individually or in combination, were then input into the calibrated hydrological model (HEC-HMS) to project future hydrological variables. The results reveal that surface runoff will be increased with increased future rainfall. Land use/cover change is found to have the largest impact on increased water demand, and thus reduced future water availability. The combined scenario shows an increasing level of water stress at both the basin and sub-basin levels, especially in the dry season.  相似文献   

18.
19.
Climate change, socio-demographic change and changing patterns of ordinary consumption are creating new and unpredictable pressures on urban water resources in the UK. While demand management is currently offered as a first option for managing supply/demand deficit, the uncertainties around demand and its’ potential trajectories are problematic for water resources research, planning and policy. In this article we review the ways in which particular branches of social science come together to offer a model of ‘distributed demand’ that helps explain these current and future uncertainties. We also identify potential strategies for tracking where the drivers of change for demand may lie. Rather than suggest an alternative ‘demand forecasting’ technique, we propose methodological approaches that ‘stretch out’ and ‘scale up’ proxy measures of demand to inform water resources planning and policy. These proxy measurements could act as ‘indictors of change’ to water demand at a population level that could then be used to inform research and policy strategies. We conclude by arguing for the need to recognise the co-production of demand futures and supply trajectories.  相似文献   

20.
Cha et al. (Water Resources Management, 26(18):4183–4201 2012) improved the method used to measure the vulnerability of a reservoir water supply that arises due to water scarcity in a dry season. Water supply vulnerability is expected to increase due to climate change. The authors showed that the Gwangdong Reservoir Drought Management Model (GRDM2), developed in a previous study and based on the adaptation mechanism, is useful to estimate the vulnerability of water supplies. The authors assumed 48 future scenarios, consisting of a combination of 6 future inflow scenarios and 8 future water requirement scenarios, of the Gwangdong reservoir drought management system. They computed damage cost of water scarcity in dry seasons until the 2050s. Simulation results showed that severe damage may take place from the 2020s and damage four times greater than in the 2009 water scarcity event may occur in the 2050s. As a result, GRDM2 was reported to be useful to measure the magnitude of climate change vulnerability, concentrating on damage of water scarcity in a dry season.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号