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1.
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   

2.
Demand-side management should be used to maximize the efficiency of groundwater use. Implementation of conservation measures would decrease the volume of water use and also exert less pressure on the water distribution system as well as the wastewater treatment system. Allocation of ground water in the Great Lakes basin must conform to priorities established at the community level. Groundwater pricing should reflect the full costs arising from ground water use. A differential pricing structure would help conserve water in the residential and industrial sectors. A user-friendly database on ground water use, quality and quantity for the entire Great Lakes basin is also essential. New policies for sustainable groundwater allocation, regulating water prices for water conservation, conservation education, pollution prevention, recycling and reuse of water as well as effective information management provide new directions for managing the groundwater demand in the Great Lakes basin.  相似文献   

3.
ABSTRACT

Since independence in 1947, floods in the Indus River Basin in Pakistan have claimed more than 7,000 lives and caused massive infrastructure and crop losses. To date, flood damage reduction has received limited attention relative to the irrigation and hydropower subsectors in the basin. Nonstructural approaches to flood hazard mitigation have lagged behind engineering approaches. This article retraces the development offlood policies in Pakistan, from an early situation of risk acceptance to more recent strategies of risk management. It shows that an underlying problem, and future aim, for flood policy will lie in giving greater attention to mitigating social vulnerability to flood hazards in the basin.  相似文献   

4.
We use Mann–Kendall trend test and Lepage method to study spatial and temporal variations of the streamflow series over the past 50 years based on daily hydrologic data from six gauging stations in the Yellow River basin. Research results indicate that: (1) The streamflow of the Yellow River basin is decreasing and water resource deficit tends to be more serious from the upper to the lower Yellow River basin; (2) Zero-flow days are observed after 1970 and overwhelmingly prevail during 1990–2000. Moreover, zero-flow events are observed mainly during spring and summer; (3) Low flow events are more sensitive to climatic changes and human activities when compared to the high flow events, which is mainly reflected by larger fluctuation of timing of change points. Furthermore, the timing of change point of hydrologic events tends to be earlier from the upper to the lower Yellow River basin, indicating more intensive impacts of human activities on water resource in the lower Yellow River basin. The current research will be greatly helpful for sound and effective water resource management in the Yellow River basin, being characterized by serious water deficit.  相似文献   

5.
James Horne 《国际水》2017,42(8):1000-1021
This paper examines three actions by national and state governments – the role of the Cap, the Living Murray (TLM) and the National Action Plan for Water Security/Water for the Future, embodying the Murray–Darling Basin (MDB) Plan – in the Murray–Darling Basin over a 20-year period. The three actions sought to address declining environmental conditions through water policy reform. All were significant in their own way, but only the third offers the prospect of improving environmental outcomes. Taken together, the case studies illustrate that in real life and in complex, multilevelled policy-making, politics is central to water policy decision-making.  相似文献   

6.
This study was conducted to assess water availability and consumption in the Karkheh River Basin in Iran using secondary data and freely available satellite data. Precipitation was estimated using geo-statistical techniques while a Surface Energy Balance approach was selected for evapotranspiration estimation. The spatial distribution of actual evapotranspiration (ETa) for the Karkheh Basin has been estimated by use of 19 cloud free Moderate Resolution Imaging Spectroradiometer (MODIS) images, which cover a complete cropping year from November 2002 to October 2003. ETa estimates were compared to potential crop evapotranspiration (ETp) estimates for two predominantly irrigated wheat areas in Upper and Lower Karkheh. Differences were found to be 12.5% and 11.7% respectively. Results of the ETa and precipitation estimates reveal that for the study period, the Karkheh Basin received 18,507 × 106m3 as precipitation while ETa is estimated at 16,680 × 106m3. Estimated outflow from the basin for the study period only is 7.8% of the precipitation and indicates that water is a very scarce resource in the Karkheh basin. The basin has been divided in sub-basins to allow for more detailed analysis and results indicate that water balance closure at sub-basin scale ranges from 7.2% to 0.6% of the precipitation. This suggests that the water balance is sufficiently understood for policy and decision making.  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.
1 IntroductionIn the central Yangtze Basin in China ,there were thou-sands of large lakes .In the past , most of them were naturallyconnected with rivers ,such as the Yangtze ,but gradually losttheir hydrological and biological linkages due to both natura…  相似文献   

9.
Jingjie Yu  Wenju Cai  Tim Cowan 《国际水》2013,38(3):313-323
The relationship between the interannual changes in streamflow, precipitation and temperature of the Murray–Darling basin is investigated by using a two-parameter climate elasticity of streamflow approach. The non-linear relationship between streamflow and both precipitation and temperature indicates a greater streamflow sensitivity to precipitation than to temperature but a more significant impact of temperature change on streamflow than previously reported. The physical mechanisms producing high streamflow sensitivity to temperature change are not well understood, but may relate to concurrent changes in sub-annual precipitation characteristics such as seasonality, spatial distribution and intensity. Thus these characteristics need to be assessed and accounted for when attempting to project how streamflow, and hence water availability, may change in a future warmer world.  相似文献   

10.
基于1979—2019年江苏省太湖流域雨量站实测降水资料,综合解析了全球性降水资料MSWEP(multi-source weighted-ensemble precipitation)对日降水量和各历时极值降水量的表征能力。结果表明:MSWEP对研究区日降水量总体上有较强的解释能力,但在山丘区较集中的湖西区和以水域为主的太湖区两个水利分区的精度相对较差,同时MSWEP难以捕捉到暴雨等级的日降水事件;MSWEP可大致反映研究区各历时极值降水量的空间分布格局,但在细节特征上与地面降水场仍有一定差异;随着历时增加,MSWEP极值降水量的精度不断提高,MSWEP对15 d及更长历时极值降水量具有较强的定量表征能力;MSWEP日降水量和极值降水量的误差与降水强度之间均有显著的线性负相关性,存在较明显的“低值高估、高值低估”现象,且MSWEP的精度与空间尺度有关;在研究区面平均尺度上,由于降水量的空间均化效应和尺度不匹配性的消除,MSWEP对日降水量和极值降水量的表征能力明显优于栅格尺度。  相似文献   

11.
Ecological classifications of stream ecosystems have been used to develop monitoring programs, identify reference and impacted systems, and focus conservation efforts. One of the most influential, but highly variable, components of stream ecosystems is water temperature but few geographically broad-scale and long-term programs exist to assess and monitor temperatures. This study evaluated if existing ecological classifications could be used to categorize the similarities and differences in stream temperatures across the Ontario portion of the Great Lakes Basin. Concordance between the spatial variability in temperatures and an existing ecological classification would support the use of that classification to define areas with similar temperatures, guide the development of a monitoring program, and inform management programs. The five classifications evaluated were the ecoregions and ecodistricts defined in the National Ecological Framework for Canada, the ecoregions and ecodistricts defined in the Ecological Land Classification of Ontario, and the aquatic ecosystem units defined in the Aquatic Ecosystem Classification (AEC) for the Ontario portion of the Great Lakes Basin. Hierarchical linear modelling and corrected Akaike Information Criterion indicated that the ecodistrict classifications characterized more of the spatial variability in temperatures than the ecoregion and AEC classification but temperatures were more variable among sites within classes than between classes. Therefore, none of the existing ecological classifications could be used to characterize thermal variability. Future research should examine if the inability of the existing classifications to capture the thermal variability translates into inaccurate classification of other ecosystem components such as water quality, and macroinvertebrate and fish assemblages.  相似文献   

12.
The current paper aims at analyzing the behavior of monthly precipitation in the Brazilian and Bolivian parts of the basin of the Madeira river, one of the most important sub-basins of the Amazon basin. Both parts account for 93 % of its total, and studies on this topic are lacking. The research was based on data from 41 rainfall stations considering a historic series from 1978 to 1998, which encompasses two of the largest El Niño events (1982–1983 and 1997–1998), hence its influence on the precipitation of the region was assessed as well. To study precipitation behavior, rainfall was regionalized using data clustering methods (Ward and K-means), with the basin being divided into five regions of homogeneous rainfall. Both methods were applied to the regions and showed similar results, providing a higher reliability for the clusters obtained. The results of the analysis show the homogeneous regions of the basin, the spatial variability of precipitation, seasonality and the influence of the phenomenon on the region.  相似文献   

13.
Experiments are carried out in an "S-shaped" flume in the laboratory under both open flow and ice-jammed conditions to study the impacts of bridge piers in a bend channel on the variation of the water level. The variations of the water level under the ice jammed condition with bridge piers are compared to those without bridge piers in an 180° bend channel. Results indicate that the bridge piers in the S-shaped channel have obvious impacts on the ice accumulation and the water level. The increment of the water level with the presence of the bridge piers is less than that without the bridge piers in the channel. Different arrangements of the bridge piers result in different increments of the water level. When one bridge pier is installed in the straight section of the channel(between 2 bends) and another one at the bend apex(for a convex bank), the increment of the water level during the equilibrium ice jammed period is between that with a single bridge pier located in the straight section of the bend channel and that with a single bridge pier located at the bend apex. It is also shown that the increment of the water level during the equilibrium ice jammed period increases with the increase of the average thickness of the ice jams.  相似文献   

14.
15.
Hydropower and irrigation developments to address rising demand for food and energy are modifying the water balance of the Mekong Basin. Infrastructure investment decisions are also frequently made from a sub-catchment perspective. This paper compares river flows with irrigation development stages in the Nam Ngum sub-basin where the potential for irrigation and hydropower expansion is largely untapped. It shows that full hydropower development in this basin allows irrigation water use to triple, even as it reduces competition with environmental flow requirements. The implications for the wider Mekong are, however, unclear, particularly given uncertainty over parallel transformations elsewhere in the basin.  相似文献   

16.
17.
An integrated hydrologic/hydraulic model of the Kemptville Creek basin has been built using the Mike11 modeling system of the Danish Hydraulic Institute and available GIS-based watershed data. This watershed system is complex, comprising of channels, local drainage areas, lateral inflows, wetlands, and a regulated dam. The model was calibrated using measured streamflow data for five years and then validated for another five years. A wide range of methods??both qualitative and quantitative??were used to evaluate the model performance. It was found that the model can simulate high flows with a high degree of accuracy, and the low flows less satisfactorily. Additional (split-sample) validation tests were conducted for another two five-year periods, which revealed that the model is capable of performing equally well for time periods beyond those used for calibration and validation. This model is now being used for various watershed management purposes, including synthetic hydrograph generation, flood forecasting, design flood estimation, wetland function analysis, etc.  相似文献   

18.
Glyphosate-based herbicides used to control weeds and invading alien plant species in South Africa ultimately end up in freshwater ecosystems, but no South African environmental water quality guideline exists to regulate these bio-active chemicals. Ecotoxicological tests to assess the possibility of using lipid peroxidation (LPx) in Caridina nilotica as a potential biomarker of Roundup(?), a glyphosate-based herbicide, pollution were conducted. In two separate tests, 40 days post hatch shrimps were exposed to different concentrations of 4.3, 6.7, 10.5, 16.4, 25.6 and 40.0 mg/L in a 96 h acute toxicity test; and 2.2, 2.8, 3.4, 4.3 and 5.4 mg/L in a 21 d chronic toxicity test, using static-non renewal and static-renewal methods, respectively. Shrimp whole body LPx was estimated by thiobarbituric acid reactive species (TBARS) assay, performed by a malondialdehyde (MDA) reaction with 2-thiobarbituric acid (TBA) measured spectrophotometrically. Final MDA concentrations were expressed as nmol MDA produced/mg protein. Results showed that LPx was significantly lower in control animals than in animals exposed to different Roundup(?) concentrations, (p < 0.05). The present work provides an ecotoxicological basis for the possible use of LPx in Caridina nilotica as a biomarker for monitoring Roundup(?) pollution in freshwater ecosystems.  相似文献   

19.
The effect of soil stratification was studied through numerical investigation based on the coupled model of solute transport in deformable unsaturated soil. The theoretical model implied two-way coupled excess pore pressure and soil deformation based on Biot's consolidation theory as well as a one-way coupled volatile pollutant concentration field developed from the advection-diffusion theory. Embedded in the model, the degree of saturation, fluid compressibility, self-weight of the soil matrix, porosity variance, longitudinal dispersion, and linear sorption were computed. Based on simulation results of a proposed three-layer landfill model using the finite element method, the multi-layer effects are discussed with regard to the hydraulic conductivity, shear modulus, degree of saturation, molecular diffusion coefficient, and thickness of each layer. Generally speaking, contaminants spread faster in a stratified field with a soft and highly permeable top layer; soil parameters of the top layer are more critical than the lower layers but controlling soil thicknesses will alter the results. This numerical investigation showed noticeable impacts of stratified soil properties on solute migration results, demonstrating the importance of correctly modeling layered soil instead of simply assuming the averaged properties across the soil profile.  相似文献   

20.
The use of Caridina nilotica whole-body acetylcholinesterase (AChE) activity as a potential biomarker of Roundup(?) pollution of aquatic ecosystems was investigated. Forty days post hatch (dph) shrimps were exposed to different concentrations of 0.0, 4.3, 6.7, 10.5, 16.4, 25.6 and 40.0 mg/L in a 96 h acute toxicity test; and 0.0, 2.2, 2.8, 3.4, 4.3 and 5.4 mg/L in a 21 d chronic toxicity test. Whole-body AChE activities were determined at the end of the exposure periods by spectrophotometric assay of sample extract; activities were then normalized against protein contents in the samples and expressed in nanomoles of substrate hydrolyzed. Results of both tests showed that AChE activity was concentration-dependent. Mean AChE activities and standard deviations (±SD) for 96 h acute toxicity were 3.6239 (± 0.4185), 3.4157 (± 1.1842), 2.537 (± 1.3989), 2.4253 (± 1.4202), 2.4127 (± 1.9097), 2.0017 (± 1.1080) and 2.316 (± 0.4001) nmol/min/mg protein; while activity levels for 21 d test were 3.6907(± 0.3401), 2.8473 (± 0.713), 2.9134 (± 0.9879), 2.6738 (± 0.7117), 2.3019 (± 0.4464) and 2.1478 (± 0.864) nmol/min/mg protein. Reference basal AChE activity for 40 dph C. nilotica based on the two control groups was estimated as 3.6907 (± 0.3401) nmol/min/mg proteins. The present work provides ecotoxicological basis for the possible use of AChE activity in C. nilotica as a biomarker for monitoring Roundup(?) pollution in freshwater systems.  相似文献   

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