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1.
In many countries groundwater resources are under-appreciated and, therefore, underutilizied; whereas, in some areas they are inappropriately exploited and, therefore, over-utilized. “Over utilization” can lead to depletion in quantity or a degradation in quality or both. Obstacles to effective management include: (1) lack of knowledge of basic principles of groundwater science among water planners, (2) in many, if not in most countries, ownership of groundwater is in the private domain with the result that codependence is unrecognized, and (3) a misunderstanding by water planners of the concepts of “overexploitation%rdquo; and conjunctive use. The economic, social, and hydrologic constraints and procedures for management for sustainable development of groundwater are significantly different from those for surface water because these differences result from such things as (1) groundwater development is not dependent on large scale collective projects (unlike the utilization of surface water that requires engineering structures for diverting, regulating and transporting water), (2) the activities of many different groups can affect the quality of water, and (3) users of groundwater often are not aware of their co-dependence on the groundwater heritage in which each participates. Hydrogeologists should try to identify those governmental policies that have a detrimental environmental effect, promote those policies that are beneficial, and demonstrate the need for a policy in matters where a policy is lacking.  相似文献   

2.
Some of the most important issues surrounding unconventional oil and gas (UOG) extraction are the possible impacts of this activity on potable groundwater resources and how to minimise and mitigate such impacts. A groundwater vulnerability map for UOG extraction has been developed as part of an interactive vulnerability map for South Africa in an effort to address such concerns and minimize possible future impacts linked to UOG extraction. This article describes the development of the groundwater theme of the interactive vulnerability map and highlights important aspects that were considered during the development of this map, which would also be of concern to other countries that may plan to embark on UOG extraction. The policy implications of the groundwater vulnerability map for managing UOG extraction impacts is also highlighted in this article.  相似文献   

3.
The increased opportunity to choose one’s school of preference has been raised as a key factor in many countries to promote equal opportunities and a higher quality of education. This has been endorsed by policymakers who assume that students make well-informed rational choices and that students stress only academic quality when deciding which school to attend. If this is true, it will benefit schools of high academic quality, rendering improved school quality overall. To date, little research has examined the validity of these assumptions despite the profound effects they have had for changing the school systems in many countries. This article describes an experiment to investigate the relative importance of factors in school choice. The aim is to test the validity of the theoretical assumptions that guided the school choice reforms in Sweden. Specifically, we draw on experimental data from prospective upper secondary school students in Sweden to contrast the principal school quality attributes behind the policy change (knowledge reputation and program feasibility), with the presence of friends and geographical attributes such as distance, location and accessibility, while controlling for individual characteristics. The results have important policy implications as they show that geographical factors are highly relevant for school choice preferences. In contrast to the reforms’ intentions, geography appears to have become more important than ever before. The findings thus reveal significant flaws in the assumptions that motivated the school choice policy reform.  相似文献   

4.
This paper explores how analytical hydrologic models can inform the effective design and choice of policy instruments to manage groundwater quality by coupling a social-planner’s problem of optimal groundwater-quality management with analytical solutions from the hydrology literature. A theoretical analysis is performed in order to characterize the properties of an optimal emissions policy. The model is then applied in a numerical analysis of groundwater contamination by chloride from highway deicers, demonstrating the relevance of the theoretical results to practical management settings. This analytical approach can help determine which policy instruments are likely to be effective in controlling groundwater pollution, especially if costly numerical groundwater models are not available for the aquifer in question. Unlike previous economic studies of groundwater contamination, this approach defines optimal emissions policies as a function of geophysical parameters employed by hydrologists such as distance between source and sink, groundwater velocity, and aquifer dispersivity. The theoretical section of this paper also demonstrates that the relationship between geophysical parameters and optimal emissions levels may be ambiguous.  相似文献   

5.
In many cases, the development of groundwater resources to boost agricultural production in dry areas has led to a continuous decline in groundwater levels; this has called into question the sustainability of such exploitation. In developing countries, limited budgets and scarce hydrological data often do not allow groundwater resources to be assessed through groundwater modeling. A case study is presented of a low-cost water-balance approach to groundwater resource assessments in a 1,550 km2 semi-arid region in northwestern Syria. The past development of irrigated agriculture and its effect on the groundwater system were studied by analysis of Landsat images and long-term groundwater level changes, respectively. All components of the groundwater balance were determined. Groundwater recharge was estimated using the chloride mass balance method. Over the past three decades, groundwater levels have declined, on average, 23 m, coinciding with a two-fold increase in the groundwater-irrigated area. Groundwater resources are currently depleted by a value that lies between 9.5×106 and 118×106 m3 year?1, which is larger than can be compensated for by a future decrease in natural discharge or changes in boundary conditions. However, groundwater resources are likely to be sufficient to supply domestic and livestock needs in the area.  相似文献   

6.
The establishment of water governance in emergency situations supports timely and effective reaction with regard to the risk and impact of natural disasters on drinking-water supplies and populations. Under such governance, emergency activities of governmental authorities, rescue and aid teams, water stakeholders, local communities and individuals are coordinated with the objective to prevent and/or mitigate disaster impact on water supplies, to reduce human suffering due to drinking-water failure during and in the post-disaster period, and to manage drinking-water services in emergency situations in an equitable manner. The availability of low-vulnerability groundwater resources that have been proven safe and protected by geological features, and with long residence time, can make water-related relief and rehabilitation activities during and after an emergency more rapid and effective. Such groundwater resources have to be included in water governance and their exploration must be coordinated with overall management of drinking-water services in emergencies. This paper discusses institutional and technical capacities needed for building effective groundwater governance policy and drinking-water risk and demand management in emergencies. Disaster-risk mitigation plans are described, along with relief measures and post-disaster rehabilitation and reconstruction activities, which support gradual renewal of drinking-water services on the level prior to the disaster. The role of groundwater governance in emergencies differs in individual phases of disaster (preparedness, warning, impact/relief, rehabilitation). Suggested activities and actions associated with these phases are summarized and analysed, and a mode of their implementation is proposed.  相似文献   

7.
As an important part of water resources of the five countries of Central Asia, groundwater resources give critical supports to the regional economic development. Accompanied by rapid economic development, the demand of groundwater is increasing. As a result, the governments are paying more attention to groundwater resource development and utilization. However, there are noticeable issues and contradictions in water resource exploration in these countries. To be more specific, these countries lack the studies in development potential and conception planning, thus influencing the sustainable groundwater development. This paper mainly discusses groundwater development problems in the five countries of Central Asia, and briefly introduces volumes and distribution of transboundary groundwater. In addition, it analyzes the current exploitation status of groundwater and studies the potential in utilizing the resource. Most importantly, it proposes creative ways to address groundwater development issues: To make best of the resource, international cooperation is required.  相似文献   

8.
Groundwater/surface-water interaction is receiving increasing focus in Africa due to its importance to ecologic systems and sustainability. In South Africa??s 1998 National Water Act (NWA), water-use licenses, including groundwater, are granted only after defining the Reserve, the amount of water needed to supply basic human needs and preserve some ecological integrity. Accurate quantification of groundwater contributions to ecosystems for successful implementation of the NWA proves challenging; many of South Africa??s aquifers are in heterogeneous and anisotropic fractured-rock settings. This paper reviews the current conceptualizations and investigative approaches regarding groundwater/surface-water interactions in the context of South African policies. Some selected pitfall experiences are emphasized. The most common approach in South Africa is estimation of average annual fluxes at the scale of fourth-order catchments (??500 km2) with baseflow separation techniques and then subtracting the groundwater discharge rate from the recharge rate. This approach might be a good start, but it ignores spatial and temporal variability, potentially missing local impacts associated with production-well placement. As South Africa??s NWA has already been emulated in many countries including Zambia, Zimbabwe and Kenya, the successes and failures of the South African experience dealing with the groundwater/surface-water interaction will be analyzed to guide future policy directions.  相似文献   

9.
In arid and semi-arid countries worldwide, conflicts between human development activities and conservation of groundwater resources are widespread and attract many public debates. This research aims to propose groundwater management alternatives for a coastal aquifer by studying its vulnerability and in particularly the risk of seawater intrusion. An additional objective is to propose some agricultural policies aimed to conserve groundwater resources in Mahdia and Ksour Essaf. Intensive groundwater mining, for irrigation and for water drinking, has caused an overexploitation of the water resources. In addition, the degradation of water quality, caused by septic tanks and intensive agricultural activities, has given rise to notable crucial state of the groundwater resources. With the aim of tackling the groundwater degradation problem, integration into a common platform of vulnerability assessment, seawater intrusion modelling and hydrochemical analysis is proposed. This platform can considerably reflect the water resources state in order to propose some solutions reducing the contamination of the Mahdia–Ksour Essaf aquifer. The groundwater management alternatives, proposed in this study, were prepared within a geographical information system.  相似文献   

10.
The 60th anniversary of the founding of the International Association of Hydrogeologists (IAH) is an important milestone that allows pause for reflection on how the association has evolved over the years and the contributions it has made to groundwater science and water management. IAH was founded in 1956 at the 20th International Geological Congress and developed rapidly during the 1980s and 1990s in response to a growing global interest in groundwater mapping and in sound approaches to resource protection and sustainable aquifer management. Incorporated in 2000, IAH has now secured its position as the world’s leading international association specialising in groundwater with over 4,100 members in 131 countries. Much credit for this success must go to members, past and present, whose individual efforts and collaboration with sister institutions are documented here. These members have shaped the association’s goals and contributed selflessly to its scientific programmes, publications and educational and charitable activities. Looking ahead to the next 60 years, it is essential that IAH does not rest on past achievements but listens and adjusts to the needs of members while continuing to pursue its mission of furthering the understanding, wise use and protection of groundwater resources throughout the world.  相似文献   

11.
Modern, small-scale renewable energy technology has the potential to enable and sustain rural livelihoods, particularly in developing countries remote locations without access to the grid. Yet, the provision of rural energy to isolated communities might not achieve the desired long-term result unless its development is part of wider national policy geared to sustainable development and social equity. This article shows how a combination of technology and policy targeted at the improvement of livelihoods in rural areas is the best solution for maximising the capacity of renewable energy to deliver services. It pinpoints the transforming processes and the institutions participating in the delivery of energy technology. This work draws on the Cuban experience of renewable energy technology, that country’s efforts to improve quality of life for remote populations, and its pledge to promote environmental sustainability. Using a sustainable livelihoods approach, the results of a survey in a rural community are analysed in the framework of existing assets and policies. The article describes how it is not only local users who benefit from a comprehensive technical, social and environmental energy approach. The same governmental administration that promotes such services has much to gain from technology that works well, benefits the poor in remote locations and protects the environment within its larger policy promoting sustainable and egalitarian society.  相似文献   

12.
地下水的分类和基岩裂隙水的基本概念   总被引:3,自引:0,他引:3  
论文深入地论述了“地下水类型”及“基岩裂隙水”这两个重要概念的认识过程。根据新近的地下水勘探资料,论文指出了目前通用的地下水介质分类存在的问题,提出了地下水介质分类的新方案和基岩裂隙水的新概念。  相似文献   

13.
The major contributions to our knowledge of the geological history of the East Saharan countries are described. Much work has been published on the history and progress of geographical, socioeconomic and archaeological exploration in North Africa. Little attention, however, has been paid to the question of how our knowledge of the geology of this vast area was developed. Thus, even though progress in geology is vital to the development of Saharan countries, little has been recorded of this progress. Without an understanding of regional geology and without a good knowledge of groundwater, mineral and petroleum potentials, these countries would be in very different situations today. The author has, over the last 35 years, been involved in scientific research and exploration of petroleum, mineral and groundwater resources in Libya, Egypt, Sudan and Chad.  相似文献   

14.
The temporal and spatial distributions of precipitation are extremely uneven; so, careful management of water resources in Taiwan is crucial. The long-term overexploitation of groundwater resources poses a challenge to water resource management in Taiwan. However, assessing groundwater resources in mountainous basins is challenging due to limited information. In this study, a geographic information system (GIS) and stable base-flow (SBF) techniques were used to assess the characteristics of groundwater recharge considering the Wu River watershed in central Taiwan as a study area. First, a GIS approach was used to integrate five contributing factors: lithology, land cover/land use, lineaments, drainage, and slope. The weights of factors contributing to the groundwater recharge were obtained from aerial photos, geological maps, a land use database, and field verification. Second, the SBF was used to estimate the groundwater recharge in a mountainous basin scale. The concept of the SBF technique was to separate the base-flow from the total streamflow discharge in order to obtain a measure of groundwater recharge. The SBF technique has the advantage of integrating groundwater recharge across an entire basin without complex hydro-geologic modelling and detailed knowledge of the soil characteristics. In this study, our approach for estimating recharge provides not only an estimate of how much water becomes groundwater, but also explains the characteristics of a potential groundwater recharge zone.  相似文献   

15.

Water scarcity is a critical issue worldwide, and Chile is no exception. Since 2010, Central Chile has been enduring an ongoing water crisis due to the coupled effects of a severe drought and the overuse of water resources, especially groundwater. Rural communities have been strongly impacted, mainly because wells from which drinking water is supplied show a dramatic drop in water levels, and some have even dried up. The water scarcity scenario requires the integration of actors and disciplines to increase awareness of groundwater; however, how to make this valuable element visible in society is an issue that remains open to debate. This paper describes and reflects on the process of making educational material about groundwater and water scarcity for children to promote public awareness. Based on transdisciplinary and co-designing processes, this work describes the social perceptions of groundwater among children and community leaders, as well as how scientific information and local knowledge of water scarcity could be integrated into a book for the young population. This research finds that educational projects on groundwater resources increase people’s awareness of the role of this hidden resource in the water cycle. Such projects encourage the creation of grounded and contextualised materials that incorporate the knowledge and experience already present in the communities, increasing public awareness of the role of groundwater and associated water scarcity issues, thereby integrating academia and society. This approach could be a tool to lay the foundations for successfully addressing the water crisis in Chile over generations.

  相似文献   

16.
城市化对水资源的影响   总被引:13,自引:1,他引:13  
钟华平 《世界地质》1996,15(4):49-53,58
城市化是世界各国发展的共同趋势,城市缺水已成为全球关注的问题,城市化对水资源产生重大影响,使城市供水不足,影响工业生产和人民日常生活;导致地下水超采,出现一系列环境地质问题;大量的污,废水排放,造成水质恶化,环境污染,并影响人民的健康,必须取取有效措施,使水资源能持续开发利用。  相似文献   

17.
Much of southern and eastern Africa is semi-arid and heavily groundwater dependent. Borehole drilling commenced over a hundred years ago with magnetic and electrical resistivity surveys for borehole siting being introduced from 1936. Formalised training of hydrogeologists led in the 1970s to an almost standard approach to hydrogeological investigation and a period of stability followed, during which some major investigations were carried out. A period of decentralisation and fragmentation has since taken place in many parts of southern and eastern Africa, and groundwater monitoring and management are inadequate in many countries. All but six of the 14 SADC (Southern African Development Community) member states reportedly have an adequate monitoring network in place. However, groundwater demand is increasing and hydrogeologists need to promote the use of appropriate methodologies as an essential part of tackling the severe issues now facing the water sector in the region.  相似文献   

18.
地下水资源保护的立法研究   总被引:2,自引:1,他引:2  
邱志勇  苏学云 《地下水》2007,29(6):7-10,39
我国许多地方因过度开采利用地下水、地下采矿疏干排泄地下水而引发了多种地质灾害,同时,地下水污染趋势愈演愈烈,导致了大范围地下水环境恶化,已经到了威胁人类生存和危害社会公共安全的程度,亟待加强地下水资源保护,改善生态环境已经刻不容缓.分析了造成地下水环境恶化的主要原因,地下水资源保护管理中存在的操作难问题,提出了地下水资源保护立法的核心内容和基本思路,进一步完善地下水资源保护的立法、执法,科学管理和保护地下水资源,促进地下水资源利用的良性循环.  相似文献   

19.
Groundwater is an important and readily available source of fresh water in the Mekong-Lancang River Basin. With a rapid population growth and increasing human activities, an increasing number of countries in the Mekong-Lancang River Basin are experiencing depleted and degraded groundwater supplies. In transboundary river basins, such as the Mekong-Lancang River, prioritizing the use of the shared aquifer by one riparian government may affect the opportunities of other riparian governments and lead to potential water conflicts between neighboring countries. To promote the sharing of strategies and information for the sustainable and equitable use of water resources of the shared basin, international collaborative workshops on groundwater resources have been organized for all Mekong-Lancang River countries. These workshops provide an opportunity to communicate and discuss nationally sensitive issues on groundwater by the associated countries, with topics covering multiple aspects of groundwater, such as the groundwater status in the basin, quality issues, water use conflicts, hydrological information gaps, management policies and capacity building for successful water resource management. Consensus has been reached by all countries on the importance of catchment-based groundwater management and the need for close communication among the countries. Strategies for managing transboundary aquifer issues must foster international collaboration based on the regional network, influence national networks and enhance the capacity to building maps and monitoring systems based on associated databases. The sustainability of water resources cannot be achieved without the integrated involvement and contributions by multiple countries and various stakeholders. Therefore, collaborative workshops provide a great opportunity to further our understanding of the hydrologic processes of the Mekong River Basin, share the benefits of the aquifer and provide a strategy and vision for sustainable water resource management in the Mekong-Lancang River countries.  相似文献   

20.
Groundwater, as a precious resource hidden underground, is an important component of the global water system. Transboundary aquifers containing substantial amount of groundwater often carry crucial ecological and social implications. Yet, it is unfortunate that transboundary aquifers have hardly been in the forefront of political and scientific discussions, and have not received due attention by policymakers. This article attempts to summarize the investigation on the eight transboundary aquifers that China shares with the neighboring countries. An overview on the groundwater resources in China, including its distribution, exploitation and challenges is also provided. Hydrogeological condition of the Heilongjiang-Amur River Basin aquifer, which is one of the eight major aquifers, is further elaborated. Cooperative activities carried out by China and Russia on monitoring and management of this aquifer are also presented.  相似文献   

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