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1.
Water resource management in Kabul river basin, eastern Afghanistan   总被引:1,自引:0,他引:1  
Severe drinking water shortage affects all resident of the Kabul river basin. Two and a half decades of civil war in Afghanistan (it began in late 1978) have resulted in widespread environmental degradation and water resource development throughout the country. The war has already finished and, therefore, water resource management for supplying water is one of the most important tasks for Afghanistan’s government. The Kabul river basin which is the most populated area in the country is located in the eastern part of Afghanistan. This article deals with the water resource properties of the Kabul river basin and also water demand in the important cities of the basin, such as Kabul, the capital and the largest city in the country. Also a few suggestions for providing water for domestic and agriculture purposes in short term, medium time and long term have been discussed.  相似文献   

2.
In recent decades, significant progress has been made toward reconstructing the past climate record based on environmental proxies, such as tree rings and ice core records. However, limited examples of research that utilizes such data for water resources decision-making and policy exist. Here, we use the reconstructed record of Palmer Drought Severity Index (PDSI), dating back to 1138AD to understand the nature of drought occurrence (severity and duration) in the state of Maine. This work is motivated by the need to augment the scientific basis to support the water resources management and the emerging water allocation framework in Maine (Maine Department of Environmental Protection, Chapter 587). Through a joint analysis of the reconstructed PDSI and historical streamflow record for twelve streams in the state of Maine, we find that: (a) the uncertainties around the current definition of natural drought in the Chapter 587 (based on the 20th century instrumental record) can be better understood within the context of the nature and severity of past droughts in this region, and (b) a drought index provides limited information regarding at-site hydrologic variations. To fill this knowledge gap, a drought index-based risk assessment methodology for streams across the state is developed. Based on these results, the opportunities for learning and challenges facing water policies in a changing hydroclimate are discussed.  相似文献   

3.
Water stress in Northern China is characterized with major, inefficient irrigation water use and rapidly growing non-agricultural water demands, as well as limited water quantity and declining water quality. Water use in the region is undergoing transfer from agricultural to municipal and industrial sectors. Currently, part of the economic loss and environmental damage due to water stress can be considered as a consequence of water transfer failures, including the current transfers, which hurt farmers' livelihood and income, and the needed transfers, which industry and cities have been waiting for but have not received. This paper starts with a discussion of the causes of water stress in Northern China, which is fundamental to understand the necessity and complexity of agricultural water transfers. Following that, it reviews water transfers in Northern China as a cause for concern over the social stability, economy and environment of the region. Based on an integrated analysis of economic, environmental, fiscal and social implications, this paper begins by identifying critical barriers to smooth water redistribution; and ends with implications for policy reforms, ensuring that farmers can and will save water. It is concluded that the decisions of water reallocation under water stress should be shared by communities at all levels, from the local to the national, to ensure equal access of water, especially the availability of the basic water need for all groups.  相似文献   

4.
Desert springs, often the sole sources of water for wildlife and cattle, support wetland and wetland/upland transition ecosystems including rare and endemic species. In the basin and range province in Nevada, USA, springs in the Great Basin and Mojave deserts are sustained by interconnected deep carbonate and shallow basin-fill aquifers which are threatened by proposed groundwater withdrawal to sustain rapidly expanding urban areas, a common problem in arid regions worldwide. This paper draws on historic groundwater data, groundwater modeling, and studies of environmental controls of spring ecosystems to speculate on the potential effects of groundwater withdrawal and water table decline on spring-supported vegetation. The focus is on springs in the Great Basin and Mojave deserts representative of those that may be affected by future, planned groundwater withdrawal. Groundwater withdrawal is expected to reduce spring discharge directly through reduced flows from the shallow basin-fill aquifer or through reduction of the hydraulic head of the deep carbonate aquifer. This flow reduction will truncate the outflow stream, reducing the areal cover of wetland and wetland/upland transition vegetation. Lowering the local water table may also reduce the amount of upland phreatophytic vegetation by causing water levels to drop below plant rooting depths. Percolation of salts to surface soils may be reduced, eventually altering desert shrub cover from halophytes to nonhalophytes. The extent of these effects will vary among springs, based on their distance from extraction sites and location relative to regional groundwater flow paths. On-site monitoring of biotic variables (including cover of selected hygrophytes and phreatophytes) should be a necessary complement to the planned monitoring of local hydrologic conditions.  相似文献   

5.
The coupled processes of climate change and urbanization pose challenges for water resource management in cities worldwide. Comparing the vulnerabilities of water systems in Phoenix, Arizona and Portland, Oregon, this paper examines (1) exposures to these stressors, (2) sensitivities to the associated impacts, and (3) adaptive capacities for responding to realized or anticipated impacts. Based on a case study and survey-based approach, common points of vulnerability include: rising exposures to drier, warmer summers, and suburban growth; increasing sensitivities based on demand hardening; and limited capacities due to institutional and pro-growth pressures. Yet each region also exhibits unique vulnerabilities. Comparatively, Portland shows: amplified exposures to seasonal climatic extremes, heightened sensitivity based on less diversified municipal water sources and policies that favor more trees and other irrigated vegetation, and diminished adaptive capacities because of limited attention to demand management and climate planning for water resources. Phoenix exhibits elevated exposure from rapid growth, heightened sensitivities due to high water demands and widespread increases in residential and commercial uses, and limited adaptive capacities due to weak land use planning and “smart growth” strategies. Unique points of vulnerability suggest pathways for adapting to urban-environmental change, whether through water management or land planning. Greater coordination between the land and water sectors would substantially reduce vulnerabilities in the study regions and beyond.  相似文献   

6.
Abstract: Rapidly growing regions such as the western United States face difficult challenges in mobilizing new water supplies to meet new demands. Environmental concerns have curtailed the scope for large new surface storage projects, and widespread basin overdraft has limited ground water’s potential as a source of expansion. Drawing on the California experience, this article explores modern water planning approaches, which focus on a portfolio of options including nontraditional sources (recycling, desalination, underground storage) and more efficient use of existing supplies (conservation and water marketing). It reviews the advantages and drawbacks of the elements of the portfolio, provides examples of innovative planning approaches, and assesses the role for supportive government policies.  相似文献   

7.
The article describes the historical development of water tariff policy in Tanzania from the colonial times to present. After gaining independence, the country introduced “free” water policy in its rural areas. Criticism against this policy was expressed already in the 1970s, but it was not until the late 1980s that change became unavoidable. All the while urban water tariffs continued to decline in real terms. In rural and periurban areas of Tanzania consumers often have to pay substantial amounts of money for water to resellers and vendors since the public utilities are unable to provide operative service. Besides, only a part of the water bills are actually collected. Now that the free water supply policy has been officially abandoned, the development of water tariffs and the institutions in general are a great challenge for the country.  相似文献   

8.
The article advances the hypothesis that the seasonal and inter‐annual variability of rainfall is a significant and measurable factor in the economic development of nations. An analysis of global datasets reveals a statistically significant relationship between greater rainfall variability and lower per capita GDP. Having established this correlation, we construct a water resources development index that highlights areas that have the greatest need for storage infrastructure to mitigate the impacts of rainfall variability on water availability for food and basic livelihood. The countries with the most critical infrastructure needs according to this metric are among the poorest in the world, and the majority of them are located in Africa. The importance of securing water availability in these nations increases every day in light of current population growth, economic development, and climate change projections.  相似文献   

9.
Hirsch, Robert M., 2011. A Perspective on Nonstationarity and Water Management. Journal of the American Water Resources Association (JAWRA) 47(3):436‐446. DOI: 10.1111/j.1752‐1688.2011.00539.x Abstract: This essay offers some perspectives on climate‐related nonstationarity and water resources. Hydrologists must not lose sight of the many sources of nonstationarity, recognizing that many of them may be of much greater magnitude than those that may arise from climate change. It is paradoxical that statistical and deterministic approaches give us better insights about changes in mean conditions than about the tails of probability distributions, and yet the tails are very important to water management. Another paradox is that it is difficult to distinguish between long‐term hydrologic persistence and trend. Using very long hydrologic records is helpful in mitigating this problem, but does not guarantee success. Empirical approaches, using long‐term hydrologic records, should be an important part of the portfolio of research being applied to understand the hydrologic response to climate change. An example presented here shows very mixed results for trends in the size of the annual floods, with some strong clusters of positive trends and a strong cluster of negative trends. The potential for nonstationarity highlights the importance of the continuity of hydrologic records, the need for repeated analysis of the data as the time series grow, and the need for a well‐trained cadre of scientists and engineers, ready to interpret the data and use those analyses to help adjust the management of our water resources.  相似文献   

10.
11.
Abundance of fecal caliform bacteria is a weak index of the presence of human pathogens in wastewater entering coastal waters. In spite of this, use of fecal caliform indices for management purposes is widespread. To gain insight into interpretation of fecal coliform data, we evaluated size of stocks of fecal coliforms in water, sediments, and sea wrack, in Buttermilk Bay, a coastal embayment in Massachusetts. Sediments contained most of the fecal coliforms. Fecal coliforms in sediments were as much as one order of magnitude more abundant than in the water column or in sea wrack. The fecal coliforms in sediments of Buttermilk Bay were so abundant that resuspension of fecal coliforms from just the top 2 cm of muddy sediments could add sufficient cells to the water column to have the whole bay exceed the federal limit of fecal coliforms for shellfishing. The major sources of fecal coliforms to the bay were water-fowls, surface runoff, groundwater, and streams. Waterfowl were the largest source of fecal coliforms during cold months; surface runoff, streams, and groundwater were most important during warm months. Redirection of surface runoff pipes is unlikely to be a very successful management action since contributions via this source are insufficient to account for the measured increases in concentrations of fecal coliforms in water. Removal of waterfowl is also unlikely to be useful, since fecal coliform concentrations leading to closures of shellfish beds and swimming areas are most frequent during warm months when waterfowl are rarest. Rates of loss of fecal caliform cells from the water column by death and tidal exchange were high. Mortality of cells was about an order of magnitude larger than losses by tidal exchange. The amounts of fecal coliforms brought into the bay by waterfowl, surface runoff, groundwater, and streams are an order of magnitude smaller than the losses by mortality and tidal removal. This implies that there is an additional source of fecal coliforms within the bay. We suggest that resuspension of the upper layers of sediments can easily account for the fecal coliforms present in the water. Fecal coliform content of water and shellfish were not correlated. In contrast, sediment and shellfish fecal coliform abundances were significantly related. Monitoring of fecal coliforms in sediments may provide a better assessment of shellfish than sampling of water. The large fecal coliform stock in sediments should be the first priority for management. Efforts ought to be directed toward the reduction of sediment fecal coliform stocks. Lowering nutrient additions to coastal water bodies may be one practical approach.  相似文献   

12.
Abstract: It is critical to understand the ability of water management to prepare for and respond to the likely increasing duration, frequency, and intensity of droughts brought about by climate variability and change. This article evaluates this ability, or adaptive capacity, within large urban community water systems (CWSs) in Arizona and Georgia. It analyzes interview data on the bridges and barriers to adapting water management approaches in relation to extreme droughts over the past decade. This study not only finds levers for building adaptive capacity that are unique to each state but also identifies several unifying themes that cut across both cases. The interviews also show that a particular bridge or barrier, such as state regulation, is not universally beneficial or detrimental for building adaptive capacity within each state. Such knowledge is useful for improving water and drought management and for understanding how CWSs might prepare for future climate variability and change by removing the barriers and bolstering the bridges in efforts to build adaptive capacity.  相似文献   

13.
A map of summer total phosphorus in lakes has been compiled for Minnesota, Wisconsin, and Michigan to clarify regional patterns in attainable lake trophic state. Total phosphorus was used as a measure of lake trophic state because: (1) phosphorus plays a central role in controlling the overall fertility of most lakes, (2) total phosphorus values are available for a great number of lakes, and (3) phosphorus is measured in a consistent manner. The maps were compiled using patterns of total phosphorus data and observed associations between these data and geographic characteristics including physiography, land use, geology, and soils. Regions depicted on the map represent areas of similarity in phosphorus concentrations in lakes, or similarity in the mosaic of values, as compared to adjacent areas. Within each region, differences in total phosphorus can be compared to natural and anthropogenic factors to determine the types of lakes representative of each region, the factors associated with differences in quality, and the realistically attainable phosphorus levels for each type of lake.  相似文献   

14.
Based on surveys and chemical analyses, we performed a case study of the surface water and groundwater quality in the Wuwei basin, in order to understand the sources of water pollution and the evolution of water quality in Shiyang river. Concentrations of major chemical elements in the surface water were related to the distance downstream from the source of the river, with surface water in the upstream reaches of good quality, but the river from Wuwei city to the Hongya reservoir was seriously polluted, with a synthetic pollution index of 25. Groundwater quality was generally good in the piedmont with dominant bicarbonate and calcium ions, but salinity was high and nitrate pollution occurs in the northern part of the basin. Mineralization of the groundwater has changed rapidly during the past 20 years. There are 23 wastewater outlets that discharge a total of 22.4 x 10(6)m(3)y(-1) into the river from Wuwei city, which, combined with a reduction of inflow water, were found to be the major causes of water pollution. Development of fisheries in the Hongya reservoir since 2000 has also contributed to the pollution. The consumption of water must be decreased until it reaches the sustainable level permitted by the available resources in the whole basin, and discharge of wastes must also be drastically reduced.  相似文献   

15.
This paper examines possible ozone-induced foliar injury to ponderosa pine areas in the Rincon Mountains of southern Arizona from 1972 to 1992. Spatiotemporal differences in a satellite-derived vegetation index (VI) are examined with respect to antecedent moisture conditions, temporal variations in ozone exposure levels, and measured foliar injury values from 1985. Seasonal ozone exposure levels (SUM60 and W126) increased from 1982 to 1998 and were significantly correlated (r = 0.49 and 0.53, α= 0.05) with annual population totals in the Tucson area. Extensive masking of satellite images from 1972, 1986, and 1992 resulted in two optimal change detection areas, with one site, TVWMica, exposed mostly to the Tucson air pollution plume, while the other site, EMica, was more protected from Tucson-derived pollution. An overall increase in VI from 1972 to 1992 at both sites appears to have been caused by an increase in moisture availability. Larger foliar injury values in 1985 were associated with a smaller increase in VI (i.e., a smaller increase in green leaf biomass) from 1972 to 1986. From 1972 to 1986 and from 1986 to 1992, VI values at TV/WMica increased at a slower rate compared to those at EMica. The reduced increase in “green-up” may have been caused partially by ozone-induced foliar injury and resulting decreases in green leaf biomass. However, these spatial differences in VI values may have also been caused by a number of other factors. Results nevertheless reveal the strong possibility of distinct, topographically based, spatial variations in ozone-induced foliar injury within the Rincons.  相似文献   

16.
Both permit requirements and ecological assessments have been used to evaluate mitigation success. This analysis combines these two approaches to evaluate mitigation required under Section 404 of the United States Clean Water Act (CWA) and Section 10 of the Rivers and Harbors Act, which allow developers to provide compensatory mitigation for unavoidable impacts to wetlands. This study reviewed permit files and conducted field assessments of mitigation sites to evaluate the effectiveness of mitigation required by the US Army Corps of Engineers for all permits issued in Orange County, California from 1979 through 1993. The 535 permit actions approved during this period allowed 157 ha of impacts. Mitigation was required on 70 of these actions, with 152 ha of enhanced, restored, and created habitat required for 136 ha of impacts. In 15 permit actions, no mitigation project was constructed, but in only two cases was the originally permitted project built; the two cases resulted in an unmitigated loss of 1.6 ha. Of the remaining 55 sites, 55% were successful at meeting the permit conditions while 11% failed to do so. Based on a qualitative assessment of habitat quality, only 16% of the sites could be considered successful and 26% were considered failures. Thus, of the 126 ha of habitat lost due to the 55 projects, only 26 ha of mitigation was considered successful. The low success rate was not due to poor enforcement, although nearly half of the projects did not comply with all permit conditions. Mitigation success could best be improved by requiring mitigation plans to have performance standards based on habitat functions.  相似文献   

17.
2 were sampled in order to verify the impact of these problems on groundwater. All samples were analyzed for major ions, and about 30 of them for fecal coliforms and heavy metals. Nineteen samples were selected for pesticide analyses. The average nitrate content was 80 mg/liter, eight times the regional background value. Fecal coliforms were detected in 60% of the analyzed samples. Zinc content and a high Cl/HCO3 ratio were observed in the surroundings of the solid waste disposal area. Moreover, lindane and heptachlor pesticides were detected in ten samples.  相似文献   

18.
This article examines the history and character of the water supply in Trinidad and Tobago and the nature of problems associated with the procurement of water by Trinidadians. The article reports on case studies of two rural communities in which women have taken the lead to solve water problems. It reflects on the importance of small‐scale, community‐managed water systems for the possibility of achieving water democracy.  相似文献   

19.
This report briefly describes the implementation process involving nature conservation considerations in forestry, according to a recently passed law in Sweden. Described are the forestry and political systems in Sweden regarding nature conservation in forestry, as well as of the administrative process involved when a forest is going to be clearcut. Conclusions are based upon the conditions and outcome of two clearcutting cases outlined in this report, and are focused on the interactions and control functions among various agencies and levels of government. The policy on the consideration of nature in forestry is, to a large extent, formed at a very low level in the bureaucracy and is subject to negotiation from case to case. Checkups between different agencies as a form of concurrent government become important means of implementing environmental considerations in forestry, having the split roles and interests of the authorities in mind.  相似文献   

20.
A milestone in the field of European water protection policy is the European Union’s Water Framework Directive (WFD), which came into force in December 2000 and which integrates the management of European waters in many ways. In this study, we start by focusing on management issues connected to the implementation of the WFD and pose a question: “what type of models would be the most suitable for use in the context of the WFD?” With this question in mind, we aim to establish a set of operational and functional selection criteria for (computer) models whose application is intended to support decision-making related to a particular water management issue. These so-called “benchmark criteria” should help water managers and other model users in choosing appropriate models, e.g., for the WFD implementation purposes. We first describe models and their use in general and then propose an approach for setting the benchmark criteria for models, basing it on the concept of uncertainty management, while keeping firmly in mind the important role of citizens and citizen organizations in water management. The suggested benchmark criteria are in the form of 14 questions through which each model can be evaluated. Finally, the process for testing and refining the benchmark criteria is highlighted.  相似文献   

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