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801.
归纳了资源的三类定义,回顾了资源概念中的时间尺度和价值理论问题,并对我国资源研究工作进行了总结,最后认为资源科学在21世纪将会得到长足发展,为此需要开展10个方面的研究工作,并应尽快使资源科学进入国家学科体系。 相似文献
802.
Serena Ceola Alberto Montanari Tobias Krueger Fiona Dyer Heidi Kreibich Ida Westerberg 《水文科学杂志》2020,65(Z1):2803-2817
ABSTRACTWe explore how to address the challenges of adaptation of water resources systems under changing conditions by supporting flexible, resilient and low-regret solutions, coupled with on-going monitoring and evaluation. This will require improved understanding of the linkages between biophysical and social aspects in order to better anticipate the possible future co-evolution of water systems and society. We also present a call to enhance the dialogue and foster the actions of governments, the international scientific community, research funding agencies and additional stakeholders in order to develop effective solutions to support water resources systems adaptation. Finally, we call the scientific community to a renewed and unified effort to deliver an innovative message to stakeholders. Water science is essential to resolve the water crisis, but the effectiveness of solutions depends, inter alia, on the capability of scientists to deliver a new, coherent and technical vision for the future development of water systems.
EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR not assigned 相似文献
803.
SequenceStratigraphicFeaturesofMesozoic-CenozoicNonmarineSedimentsinEasternChina¥XuHuaida;WeiKuisheng(DepartrmentofEnergyReso... 相似文献
804.
《地理学报(英文版)》1994,(Z1)
Sincethe195Os,theCentralPlaceTheory(Cpp)hasbeenprevailingallovertheWest.Nevertheless,theaPplicationofthismodelinChinasplanningworkusedtobeanargUableproblem.Negativeviewswerefl.thehyPothesisabouttl1enatUralandhumanhomogeneityisdevoicedfromthereality;2.thetheorytvasge11eratedfrol11caPitalistsociety,wherethehistorical,socialandeconomicconditionsaredifferentfromChina's.Inrecentyears,theauthorshavetriedtoapplyCppmode1toChina'Surbanal1dregionalplanning,thesatisfactoryresu1tsprovedthegenera1ada… 相似文献
805.
The geometric approach to mechanics based on the Jacobi metric allows to easily construct natural mechanical systems which are integrable (actually separable) at a fixed value of the energy. The aim of the present paper is to investigate the dynamics of a simple prototype system outside the zero-energy hypersurface. We find that the general situation is that in which integrability is not preserved at arbitrary values of the energy. The structure of the Hamiltonian in the separating coordinates at zero energy allows a perturbation treatment of this system at energies slightly different from zero, by which we obtain an analytical proof of non-integrability.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
806.
The first significant government sponsored community‐based forest management project in Australia was initiated in Central Victoria in 2002. This paper analyses the initial stage of the Wombat Community Forest Management Pilot Project. The paper develops a functional concept of ‘effective community’ for structuring community engagement in these kinds of natural resource management projects. The effective community has characteristics in common with a community of interest, adopts a bioregional perspective, embodies the values of environmental stewardship and interacts in a fully informed way as a ‘discursive community’ (Meppam 2000). The paper offers general advice for organising effective community engagement in such projects and 12 recommendations for governments developing similar initiatives elsewhere. 相似文献
807.
Mohamed?ChebaaneEmail author Hazim?El-Naser Jim?Fitch Amal?Hijazi Amer?Jabbarin 《Hydrogeology Journal》2004,12(1):14-32
Groundwater over-exploitation has been on the rise in Jordan. Competing demands have grown in the face of perennial water shortages, a situation which has been exacerbated by drought conditions in the past decade. This paper reports findings of a project in which management options to address over-exploitation were developed for one of Jordans principal aquifer systems, the Amman-Zarqa Basin. Options for addressing the situation were developed through a participatory approach that involved government officials and various public and private sector interest groups. Particular efforts were made to involve well irrigators, who are likely to be heavily impacted by the changes required to reduce groundwater pumping to a sustainable level. With information obtained from a rapid appraisal survey as well as from interviews with farmers, community groups, government officials, and technical experts, an extensive set of options was identified for evaluation. Based on integrated hydrogeologic, social, and economic analysis, five complementary management options were recommended for implementation. These included the establishment of an Irrigation Advisory Service, buying out farm wells, placing firm limits on well abstraction and irrigated crop areas, exchanging treated wastewater for groundwater, and measures to increase the efficiency of municipal and industrial water use. Various combinations and levels of these options were grouped in scenarios, representing possible implementation strategies. The scenarios were designed to assist decision makers, well owners and other stakeholders in moving gradually towards a sustainable abstraction regime. Social and economic aspects of each option and scenario were analyzed and presented to stakeholders, together with a summary of legal, institutional and environmental ramifications. Combining scientific analysis with a participatory approach in the Amman Zarqa Basin groundwater management was devised as a prototype to be used in the management of other groundwater basins in Jordan. This participatory management approach would also be useful in other parts of the world that are experiencing similar groundwater over-exploitation problems.Résumé La surexploitation des eaux souterraines prend de limportance en Jordanie. Les demandes en concurrence ont augmenté face à des déficits permanents deau, situation qui a été exacerbée par la sécheresse de la dernière décennie. Cet article rend compte de laboutissement dun projet dans lequel des options de gestion portant sur la surexploitation ont été développées pour lun des principaux systèmes aquifères de Jordanie, le bassin dAmman Zarqa. Des options pour aborder cette situation ont été développées grâce à une approche participative qui implique des fonctionnaires du gouvernement et des groupes dintérêts variés des secteurs public et privé. Des efforts particuliers ont été faits pour impliquer les irrigants utilisant des puits, qui sont probablement ceux qui ont le plus fort impact sur les changements attendus permettant de remettre le système en équilibre. À partir des informations obtenues de campagnes rapides dévaluation, telles que des réunions de communautés et des entrevues avec des experts techniques du gouvernement, un large jeu doptions a été identifié pour lévaluation. Basées sur une analyse hydrogéologique, sociale et économique, cinq options complémentaires de gestion ont été recommandées pour la réalisation. Ce sont la création dun Service Consultatif dIrrigation, achetant les puits agricoles, fixant des limites fermes aux prélèvements des puits et aux zones irriguées, échangeant les eaux usées traitées avec des eaux souterraines, et la mise en place de mesures pour accroître lefficacité des usages collectifs et industriels. Des combinaisons et des niveaux variés de ces options ont été regroupés en scénarios, présentant les stratégies possibles de mise en uvre. Les scénarios ont été mis au point pour assister les décideurs, les propriétaires de puits et les autres acteurs pour atteindre progressivement un régime de prélèvement durable. Les aspects sociaux et économiques de chaque option et de chaque scénario ont été analysés et présentés aux acteurs, en même temps quun résumé des ramifications légales, institutionnelles et environnementales. En combinant une analyse scientifique à une approche participative du bassin dAmman Zarqa, la gestion des eaux souterraines a été imaginée comme un prototype pouvant être utilisé pour la gestion dautres bassins aquifères de Jordanie. Il peut également être utile à dautres régions du monde qui sont concernées par des problèmes similaires de surexploitation des eaux souterraines.Resumen La sobreexplotación de las aguas subterráneas ha ido en aumento en Jordania, donde las demandas en competición han crecido frente a una escasez perenne de agua, situación que ha sido agravada por el estado de sequía de la última década. Este artículo presenta los hallazgos de un proyecto en el que se han desarrollado opciones de gestión para hacer frente a la sobreexplotación en uno de los principales sistemas acuíferos de Jordania: la cuenca de Ammán-Zarga. Se ha elaborado opciones para afrontar la situación mediante un enfoque participativo que incluye a personal del gobierno y a diversos grupos de interés de los sectores público y privado. En particular, se ha intentado involucrar a los regantes que se sirven de aguas subterráneas, quienes tienen más probabilidad de ser directamente afectados por los cambios requeridos para devolver el sistema a un balance equilibrado. A partir de la información obtenida en rápidas campañas de valoración, así como de encuentros con la comunidad y entrevistas con los expertos técnicos del gobierno, se ha identificado un amplio conjunto de opciones para su evaluación. Basándose en un análisis integrado de los aspectos hidrogeológicos, sociales y económicos, se ha recomendado la implementación de cinco opciones complementarias de gestión: establecimiento de un Servicio Asesor de Riego; adquisición de pozos de granjas; imposición de límites estrictos en las extracciones de pozos y superficies de riego; substitución de las aguas subterráneas con aguas residuales depuradas; y medidas para incrementar la eficiencia de los usos municipales e industriales del agua. Se ha agrupado varias combinaciones y niveles de dichas opciones en escenarios, representando estrategias posibles de implementación. Los escenarios han sido diseñados para ayudar a los gestores en la toma de decisiones, a los propietarios de pozos y a otros agentes para que se vaya consiguiendo de forma gradual un régimen de extracciones sustentable. Se ha analizado los aspectos sociales y económicos de cada opción y de cada escenario, presentándolos a los diversos agentes, además de generar un resumen de ramificaciones legales, institucionales y medioambientales. Se ha concebido la combinación de un análisis científico con un enfoque participativo en la cuenca de Ammán-Zarga como un prototipo de gestión de las aguas subterráneas que puede ser aplicado a la gestión de otras cuencas en Jordania. También sería útil en otros lugares del mundo que estén experimentando problemas similares de sobreexplotación de los recursos hídricos subterráneos.Abbreviations and acronyms AED
Academy for Educational Development
- ARD
Associates in Rural Development
- AZB
Amman–Zarqa Basin
- ECC
Economic Consultative Council
- GMCC
Groundwater Management Consultative Committee
- GMF
Groundwater Management Fund
- GIS
Geographic Information System
- HDH
Hashmiya–Dulayl–Hallabat
- IAS
Irrigation Advisory Service
- JICA
Japanese International Cooperation Agency
- M&I
Municipal and Industrial
- MOA
Ministry of Agriculture
- MWI
Ministry of Water and Irrigation
- NCARTT
National Center for Agricultural Research and Technology Transfer
- NGO
Non-governmental Organization
- O&M
Operations and Maintenance
- RA
Rapid Appraisal
- RS
Remote Sensing
- UFW
Unaccounted for Water
- USAID
United States Agency for International Development
- WAJ
Water Authority of Jordan
- WEPIA
Water Education & Public Information Activity
- WRPS
Water Resource Policy Support 相似文献
808.
Jianghui Ji Hiroshi Kinoshita Lin Liu Guangyu Li Hiroshi Nakai 《Celestial Mechanics and Dynamical Astronomy》2003,87(1-2):113-120
We perform numerical simulations to explore the dynamical evolution of the HD 82943 planetary system. By simulating diverse planetary configurations, we find two mechanisms of stabilizing the system: the 2:1 mean motion resonance (MMR) between the two planets can act as the first mechanism for all stable orbits. The second mechanism is a dynamical antialignment of the apsidal lines of the orbiting planets, which implies that the difference of the periastron longitudes 3 librates about 180° in the simulations. We also use a semi-analytical model to explain the numerical results for the system under study. 相似文献
809.
Discharge areas of hydrothermal springs are known to be inhabited by diverse types of microorganisms including archaea, prokaryotes and eukaryotes. A total of 11 hydrothermal samples from the Rio Grande rift and the Valles caldera in New Mexico were analyzed to investigate the correlation between chemical and microbiological parameters of hydrothermal waters. The sampled fluids are categorized into three chemical groups: (I) steam-condensing acid sulfate waters, (II) deep geothermal and derivative waters and (III) thermal meteoric waters. Analyses of the microbial phospholipid fatty acids and denaturing gradient gel electrophoresis of DNA show that acid sulfate waters were populated by thermoacidophilic organisms and had high biomass content. Mineralized deep geothermal and derivative waters exhibited a high degree of microbial diversity, but had low biomass content. Thermal meteoric waters are low in total dissolved solids, and exhibit very low biomass content and microbial diversity. DNA sequences from several previously unknown microbial species were detected. The results of this study support the hypothesis that microbes can be used as tracers for specific types of subsurface environments. 相似文献
810.
In the past decade, there has been significant investment in Intelligent Transportation Systems (ITS) technologies that provide information to both en‐route and pre‐trip travelers. However, there is no definitive evidence that en‐route travelers actually use the information and alter their travel patterns. Previous research employed surveys that relied on motorists' written or spoken responses to questions involving travel information and hypothetical roadway scenarios. This research examines travel behavior on freeways equipped with ITS technologies in Connecticut using collected real‐time traffic count data from the diversionary roadways. Results find that more travel is occurring on the diversionary routes during periods of variable message sign (VMS) messages than during equivalent periods having no messages, indicating a motorist travel response to these messages. 相似文献