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1.
Self-regulation of groundwater users offers tremendous potential for effective groundwater management. The attributes of higher-level authorities that are more likely to facilitate the beneficial management of groundwater in economic, social and environmental terms are discussed. For this purpose, eight groundwater user associations in Spain have been compared. Factors that support institutional change were analyzed, namely: salience, common understanding, trust and reciprocity, autonomy, prior organizational experience and local leadership. These factors are complemented by features that strengthen actions by higher-level authorities that oversee self-regulation by water users (clear boundaries, legitimate recognition of appropriators, facilitating roles, trust in cross-scale linkages, clear division of responsibilities, institutional culture and co-management model choices). Self-regulation includes the creation of reflexive organizations that are capable of learning, provided first, the administration itself is modernized to meet the challenges of self-regulation, and second, that ‘regulatory capture’ is avoided by external organizations, ensuring that the regulator and the regulated are not so close in their relationship as to be detrimental to effectiveness.
E. Lopez-GunnEmail:
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2.
A modeling study of seawater intrusion in Alabama Gulf Coast,USA   总被引:4,自引:0,他引:4  
A numerical model of variable-density groundwater flow and miscible salt transport is developed to investigate the extent of seawater intrusion in the Gulf coast aquifers of Alabama, USA. The SEAWAT code is used to solve the density-dependent groundwater flow and solute transport governing equations. The numerical model is calibrated against the observed hydraulic heads measured in 1996 by adjusting the zonation and values of hydraulic conductivity and recharge rate. Using the calibrated model and assuming all the hydrogeologic conditions remain the same as those in 1996, a predictive 40-year simulation run indicates that further seawater intrusion into the coastal aquifers can occur in the study area. Moreover, the predicted intrusion may be more significant in the deeper aquifer than the shallower ones. As the population continues to grow and the demand for groundwater pumping intensifies beyond the 1996 level, it can be expected that the actual extent of seawater intrusion in the future would be more severe than the model prediction. Better strategies for groundwater development and management will be necessary to protect the freshwater aquifers from contamination by seawater intrusion.
Jin LinEmail:
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3.
Groundwater is crucial for the livelihoods and food security of millions of people, and yet, knowledge formation in the field of groundwater has remained asymmetrical. While, scientific knowledge in the discipline (hydrology and hydrogeology) has advanced remarkably, relatively little is known about the socio-economic impacts and institutions that govern groundwater use. This paper therefore has two objectives. The first is to provide a balanced view of the plus and the down side of groundwater use, especially in agriculture. In doing so, examples are drawn from countries such as India, Pakistan, Bangladesh, China, Spain and Mexico—all of which make very intensive use of groundwater. Second, institutions and policies that influence groundwater use are analyzed in order to understand how groundwater is governed in these countries and whether successful models of governance could be replicated elsewhere. Finally, the authors argue that there is a need for a paradigm shift in the way groundwater is presently perceived and managed—from management to governance mode. In this attempt, a number of instruments such as direct regulation, indirect policy levers, livelihood adaptation and peoples participation will have to be deployed simultaneously in a quest for better governance.
Tushaar ShahEmail:
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4.
Three apparently disparate themes (groundwater, farmers and politics) interweave in this account of how groundwater-related policies in India have very little to do with the scarcity, depletion or quality of groundwater, and more to do with rural politics manifested, among other things, in terms of the presence or absence of farmer lobbies. Examples from two states of India, the water-abundant state of West Bengal and water-scarce state of Gujarat, were investigated using readily available data, analysis of the literature, interviews and fieldwork. In the case of West Bengal, although there is no pressing groundwater crisis, the government of West Bengal (GOWB) was able to successfully implement strict groundwater regulations along with a drastic increase in electricity tariff. More importantly, GOWB was able to implement these without any form of visible farmer protest, though these measures negatively affected farmer incomes. On the other hand, in Gujarat, where there is a real and grave groundwater crisis, the government of Gujarat has neither been able to implement strict groundwater regulations, nor has it been able to increase electricity tariff substantially. Thus, through the lens of ‘political ecology’ the contrasting case of these two Indian states is explained.
Aditi Mukherji (PhD Student)Email: Phone: +44-1223-477186
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5.
The regular solid solution model has been applied to solid solubility in the monazite–xenotime systems and is verified against the available experimental data for LaPO4–YPO4 and CePO4–YPO4 systems. The model is then used to predict the miscibility gaps in a number of other monazite–xenotime systems. The implications for prospective two-phase monazite–xenotime fiber coatings for applications in ceramic matrix composites (CMCs) are discussed.
P. MogilevskyEmail:
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6.
This paper describes an application of the geographic information system (GIS) technology to a ground stability assessment in the karst area of Dzerzhinsk, Russia. In the stability analysis, the groundwater level changes in the karst aquifer could cause suffosion sinkholes when the gravitational force was greater than the soil strength. The GIS technology was used to combine various data and to delineate the zones of potential gravitational collapse and suffosion collapse in the area.
V. V. TolmachevEmail:
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7.
The aim of this paper is to use an economic framework to derive decision making rules for river basin management with a focus on groundwater resources. Using an example from northern Nigeria, the paper provides an example of how decision making for sustainable water resources management may be facilitated by comparing net benefits and costs across a river basin. It is argued that economic tools can be used to assess the value of water resources in different uses, identify and analyze management scenarios, and provide decision rules for the sustainable use and management of surface and ground water resources in the region.
Gayatri AcharyaEmail:
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8.
This article explores the impacts of floods on the economy, environment, and society and tries to clarify the rural community’s coping mechanism to flood disasters in Central Viet Nam. It focuses on the social aspects of flood risk perception that shapes the responses to floods. The research findings revealed that flooding is an essential element for a coastal population, whose livelihood depend on productive functions of cyclical floods. The findings also revealed that floods, causing losses and damages, often inhibited economic development. The surveyed communities appeared to have evolved coping mechanisms to reduce the negative impacts of the floods, yet these coping mechanisms are under pressure due to environmental degradation. Integrated flood risk management is considered as a suitable paradigm for coping with flood disasters.
Phong TranEmail:
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9.
There is currently a need for a review of the definition and methodology of determining sustainable yield. The reasons are: (1) current definitions and concepts are ambiguous and non-physically based so cannot be used for quantitative application, (2) there is a need to eliminate varying interpretations and misinterpretations and provide a sound basis for application, (3) the notion that all groundwater systems either are or can be made to be sustainable is invalid, (4) often there are an excessive number of factors bound up in the definition that are not easily quantifiable, (5) there is often confusion between production facility optimal yield and basin sustainable yield, (6) in many semi-arid and arid environments groundwater systems cannot be sensibly developed using a sustained yield policy particularly where ecological constraints are applied. Derivation of sustainable yield using conservation of mass principles leads to expressions for basin sustainable, partial (non-sustainable) mining and total (non-sustainable) mining yields that can be readily determined using numerical modelling methods and selected on the basis of applied constraints. For some cases there has to be recognition that the groundwater resource is not renewable and its use cannot therefore be sustainable. In these cases, its destiny should be the best equitable use.
Donald R. WoolleyEmail:
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10.
A conjunctive use model has been developed to evaluate alternative management options for surface and groundwater resources. A simple water balance approach was used to estimate net recharge to the aquifer. The groundwater model FEFLOW takes net recharge as an input for the water balance calculation and simulates flow in the groundwater under all boundary stresses. The developed model was applied to an irrigated area in the Indus Basin, Pakistan, to predict groundwater levels up to 2010 in response to the possible need for intervention in irrigation and/or agricultural practices. A geographical information system (GIS) was used to assemble various types of spatial data. The study revealed that an increase in pumpage from the present rate would further strain the scarce water resources. Lining of watercourses and adjustment in cropping pattern could be adopted as alternatives for better management of surface and groundwater resources.
Helmut EggersEmail:
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11.
Despite the rise in importance of the private sector in the expansion of the use of groundwater in China and the potential implications this might have for production and poverty, little has been written about the effect of these phenomena on northern China’s economy. In examining determinants of tubewell privatization and its impact on producers in northern China, data were collected using a community leader survey, carried out in 448 villages in six provinces in northern China. The results show that since 1990 collective ownership of tubewells has largely been replaced by private ownership. Increasing water scarcity, government grants and bank loans for tubewell investment and the declining investment capacity of China’s local communities have led to the observed change in tubewell ownership patterns. By far, the most important positive effect on income appears to be due to the expansion of newly irrigated area that has been fueled by the rise of private tubewells. Many newly private tubewells also have begun to replace irrigation from surface water sources. While helping increase income and productivity, the rise of private tubewells also has contributed to the fall in groundwater levels.
Jinxia WangEmail: Phone: 86-10-64889841Fax: 86-10-64856533
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12.
Spatial and temporal knowledge representation   总被引:1,自引:1,他引:0  
Knowledge Representation (KR) originated as a discipline within Artificial Intelligence, and is concerned with the representation of knowledge in symbolic form so that it can be stored and manipulated on a computer. This article surveys that part of KR that is concerned with the representation of space and time, with particular reference to the use of such representations in geographical information science.
Antony GaltonEmail:
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13.
A vulnerability index for the Fire Service in the UK has been designed to identify vulnerable locations during episodes of severe floods. Taking recent case studies with the UK Fire Service, the patterns of vulnerability, in terms of demand on time and resources, can be explained by investigating the environmental causes and their interaction with the adaptive capacity of the response agencies.
Dorian SpeakmanEmail:
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14.
Finding the location of groundwater dependent ecosystems (GDEs) is important in determining the extent of restrictions that need to be placed upon the abstraction of groundwater. Remote sensing was combined with geographical information system (GIS) modelling to produce a GDE probability rating map for the Sandveld region, South Africa. Landsat TM imagery identified the areas indicating the probable presence of GDEs and GIS assisted in their delineation. Three GIS models were generated: a GIS model predicting landscape wetness potential (LWP model) based on terrain morphological features; the LWP model was modified to highlight groundwater generated landscape wetness potential (the resulting GglWP model); and a groundwater elevation model was interpolated, combining groundwater level measurements in boreholes in the region with digital elevation model data. Biomass indicators generated from Landsat were classified and combined with the GIS models, followed by field verification of riverine and wetland GDEs. The LWP model provided the most accurate results of the three models tested for GDEs in this region.
Zahn MünchEmail:
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15.
In a media saturated world of globalization, information flow and knowledge economies, an interesting paradox exists: geographic literacy appears to be on the decline while geographic information is on the rise. In this introduction to a collection of essays on geographies of the media, we explore this paradox and use Baudrillard’s (1994) work on Simulacra and Simulation to argue that increased mediated information does not produce more meaning, but rather leads to a catastrophe of meaning and the medium. Drawing from McLuhan’s axiom, “the medium is the message,” we posit that with more mediated information there is less meaningful information and as such we need to address geographic media literacy as a primary mode through which to address geographic literacy.
Jim CraineEmail:
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16.
Using density functional simulations, within the generalized gradient approximation and projector-augmented wave method, we study structures and energetics of CaSiO3 perovskite in the pressure range of the Earths lower mantle (0–150 GPa). At zero Kelvin temperature the cubic CaSiO3 perovskite structure is unstable in the whole pressure range, at low pressures the orthorhombic (Pnam) structure is preferred. At 14.2 GPa there is a phase transition to the tetragonal (I4/mcm) phase. The CaIrO3-type structure is not stable for CaSiO3. Our results also rule out the possibility of decomposition into oxides.
Daniel Y. JungEmail: Phone: +41-44-6323744Fax: +41-44-6321133
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17.
People living in the northeast of Thailand interchangeably label themselves and are labelled by others as Isan, Thai Isan, Lao Isan, Thai or Lao, depending on the ethnic, political, social or familial nuances of any given situation. I use the term Lao Isan to refer specifically to Isan people of Lao origin or ethnicity. Lao Isan are subject to complex and often competing notions of Isan-ness, Lao-ness and Thai-ness by insiders and outsiders. Using data derived from an ethnographic study of popular Thai television and Lao Isan youth (aged 17–25) living in the city of Khon Kaen and the town of Mahasarakham in northeast Thailand in 2002, this paper explores contemporary and co-existing interpretations of Isan identity or Khwampenisan among Lao Isan youth in relation to self-image and connections with national understandings of physical beauty as they are perpetuated in Thai-produced television programs.
Catherine Hesse-SwainEmail:
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18.
Important aspects of melt inclusion formation and potential compositions effects have been addressed through a series of experiments using anorthite/fosterite saturated anhydrous mafic liquids. Experimental charges were cooled from 1,300 to 1,230 and 1,210°C at rates of 1–10°/min followed by 0–24 h isothermal periods. Hopper and skeletal crystal morphologies with variable degrees of completeness developed during the cooling period. Planar overgrowth of these textures during isothermal periods led to the formation of inclusions, the majority of which formed after 6 h of isothermal run time. We suggest that the change in morphologies is related to a decrease in growth rates and changes in dominant growth mechanisms. In general, inclusion compositions were uniform and similar to the host glass, indicating that with the isothermal times required for most inclusions to form, a boundary layer was not entrapped that could be detected within the limits of our analyses.
Edward KohutEmail: Phone: +1-541-7373023Fax: +1-541-7371200
Roger L. NielsenEmail: Phone: +1-541-7371235
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19.
X-ray absorption spectroscopy at the Mg K-edge is used to obtain information on magnesium environment in minerals, silicate and alumino-silicate glasses. First-principles XANES calculations are performed for minerals using a plane-wave density functional formalism with core-hole effects treated in a supercell approach. The good agreement obtained between experimental and theoretical spectra provides useful information to interpret the spectral features. With the help of calculation, the position of the first peak of XANES spectra is related to both coordination and polyhedron distortion changes. In alumino-silicate glasses, magnesium is found to be mainly 5-fold coordinated to oxygen whatever the aluminum saturation index value. In silicate glasses, magnesium coordination increases from 4 in Cs-, Rb- and K-bearing glasses to 5 in Na- and Li-bearing glasses but remains equal as the polymerization degree of the glass varies. The variation of the C feature (position and intensity) is strongly related to the alkali type providing information on the medium range order.
Stéphanie RossanoEmail:
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20.
A large scale Proterozoic breccia system consisting of numerous individual breccia bodies, collectively known as Wernecke Breccia, occurs in north-central Yukon Territory, Canada. Breccias cut Early Proterozoic Wernecke Supergroup sedimentary rocks and occur throughout the approximately 13 km thick deformed and weakly metamorphosed sequence. Iron oxide–copper–gold ± uranium ± cobalt mineralization is associated with the breccia bodies and occurs as veins and disseminations within breccia and surrounding rocks and locally forms the breccia matrix. Extensive sodic and potassic metasomatic alteration occurs within and around breccia bodies and is overprinted by pervasive calcite and dolomite/ankerite, and locally siderite, alteration, respectively. Multiple phases of brecciation, alteration and mineralization are evident. Breccia bodies are spatially associated with regional-scale faults and breccia emplacement made use of pre-existing crustal weaknesses and permeable zones. New evidence indicates the presence of metaevaporitic rocks in lower WSG that may be intimately related to breccia formation. No evidence of breccia-age magmatism has been found to date.
Julie HuntEmail:
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