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1.
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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2.
An integrated approach to assessing the regional impacts of climate and socio-economic change on groundwater recharge is described from East Anglia, UK. Many factors affect future groundwater recharge including changed precipitation and temperature regimes, coastal flooding, urbanization, woodland establishment, and changes in cropping and rotations.Important sources of uncertainty and shortcomings in recharge estimation are discussed in the light of the results. The uncertainty in, and importance of, socio-economic scenarios in exploring the consequences of unknown future changes are highlighted. Changes to soil properties are occurring over a range of time scales, such that the soils of the future may not have the same infiltration properties as existing soils. The potential implications involved in assuming unchanging soil properties are described.To focus on the direct impacts of climate change is to neglect the potentially important role of policy, societal values and economic processes in shaping the landscape above aquifers. If the likely consequences of future changes of groundwater recharge, resulting from both climate and socio-economic change, are to be assessed, hydrogeologists must increasingly work with researchers from other disciplines, such as socio-economists, agricultural modellers and soil scientists.
I. P. HolmanEmail: Phone: +44-(0)1525-863000Fax: +44-(0)1525-863344
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3.
Recharge to a saline, unconfined shallow-water-table aquifer is normally considered as an irrecoverable loss of water, but such thinking could be reviewed empirically. The use of an appropriate groundwater harvesting system does not only provide an opportunity to recover this lost water, but can also help in catchment salinity management and improvement. Agricultural-based land-drainage systems such as those that use serial biological concentration (SBC) of salts, provide examples of such harvesting methods. The impact of groundwater harvesting has been assessed on the hydro-salinity of a saline catchment in southeastern Australia through modeling. For both the below average rainfall and very wet years, the “do nothing” scenario resulted in increasing salinization in the catchment. However, after introducing a SBC system, groundwater salinity showed a decreasing trend while hydraulic heads tended to stabilize around the depth of subsurface collector wells. However, for a successful groundwater harvesting system, proper understanding of the groundwater flows and salt mobilization associated with a catchment is necessary. The outcomes of this modelling study have the potential to address similar issues (salinization) and/or needs (water harvesting) existing elsewhere in the world, particularly in semi-arid regions.
Muhammad Nadeem AsgharEmail:
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4.
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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5.
Drilling-intensive aquifer characterization techniques have been used to obtain depth-discrete water samples from a thick, hydrogeologically continuous unconfined aquifer system; groundwater results indicate that carbon tetrachloride contamination is widespread and extends deeper and at concentrations much higher than detected in monitoring networks at the water table. Carbon tetrachloride, a legacy waste, was used in the plutonium extraction process at the Hanford site in south-central Washington State. Vertical, depth-discrete groundwater samples were collected during well drilling throughout a 28-km2 region to determine the concentration of carbon tetrachloride present as a dissolved phase in the aquifer. Results indicate that high concentrations of carbon tetrachloride, three orders of magnitude above the allowable regulatory limit, are present at depths greater than 25 m beneath the water table. In support of future efforts to remediate the carbon tetrachloride contamination, it is imperative to locate the remaining chemical inventory, determine the vertical as well as the lateral distribution of this contaminant and its physical form. Depth-discrete aquifer characterization throughout the uppermost-unconfined aquifer system is providing this information and improving the understanding of the contaminant distribution and the hydrogeologic framework through which it moves.
Bruce A. WilliamsEmail:
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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.
The impact of different land-surface parameterisation schemes for the simulation of monsoon circulation during a normal monsoon year over India has been analysed. For this purpose, three land-surface parameterisation schemes, the NoaH, the Multi-layer soil model and the Pleim-Xiu were tested using the latest version of the regional model (MM5) of the Pennsylvania State University (PSU)/National Center for Atmospheric Research (NCAR) over the Indian summer monsoon region. With respect to different land-surface parameterisation schemes, latent and sensible heat fluxes and rainfall were estimated over the Indian region. The sensitivity of some monsoon features, such as Somali jet, tropical easterly jet and mean sea level pressure, is discussed. Although some features of the Indian summer monsoon, such as wind and mean sea level pressure, were fairly well-simulated by all three schemes, many differences were seen in the simulation of the typical characteristics of the Indian summer monsoon. It was noticed from the results that the features of the Indian summer monsoon, such as strength of the low-level westerly jet, the cross-equatorial flow and the tropical easterly jet were better simulated by NoaH compared with verification analysis than other land-surface schemes. It was also observed that the distribution of precipitation over India during the peak period of monsoon (July) was better represented with the use of the NoaH scheme than by other schemes.
U. C. MohantyEmail:
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9.
The Natuf drainage basin in the western hills of Ramallah district is about 200 km2 . Many springs emerge in the area from perched aquifers and outcrop from limestone and dolomite limestone formations. This study aims to add more information about hydrochemical parameters and the chemical changes in spring water between dry and wet seasons and to locate possible sources of pollution and their effect on the water quality of water from the springs for domestic and agricultural uses. The study involved collection and analysis by conventional and available instrumental methods for the hydrochemical parameters from 12 springs before and after recharge. Water samples of runoff from two places in eastern and western parts of the study area were collected and analyzed as well. Most of the springs in the study area are of good water quality for domestic and agricultural uses. Variations in the chemical composition between dry and wet seasons, and from one spring to another, were observed. Springs near densely populated areas and agricultural activities show higher values of EC, SSP, SAR and TH. Also uncountable colonies of faecal- and total coliform were detected. Trace amounts, within World Health Organization (WHO) and the Palestinian standard limits, of cadmium, chromium, cobalt and lead are found in some springs; while concentrations of iron and zinc that were detected in springs near populated areas are higher than other springs. Water types of Ein Musbah, Al Alaq and Ein Arik El Tehta are of earth alkaline with increased portion of alkalis with prevailing bicarbonate and chloride in wet and dry seasons. Other springs show a variation in water type between earth alkaline with prevailing bicarbonate in the wet seasons to earth alkaline with prevailing bicarbonate and chloride in the dry seasons.
Marwan Ghanem (Corresponding author)Email:
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10.
With the global container population exceeding 25 million TEU (Twenty-foot Equivalent Unit) and the annual production of new boxes exceeding 3 million TEU it is estimated that around 1.5 million TEU of empty containers are sitting in yards and depots around the world waiting for use. Although utilization rates have improved since 2004, container utilization depends on the very dynamic nature of container transportation, and the container building and leasing industries. Owing primarily to the chronic trend of increasing trade imbalances across the oceans, and despite recent trends along some trade routes, the empty container management problem has become a major issue for the container shipping industry during the last decade. This paper examines and analyzes empty container logistics at a global, interregional, regional and local level. Special consideration is given to key factors affecting the empty container logistics management and strategies implemented by ocean carriers and other stakeholders to better manage empty containers.
Maria BoileEmail:
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11.
The pattern of Church of England dioceses has evolved over a period of 1,400 years. It reflects the practical response of the Church to the changing political and demographic patterns of the country. No ideal size and form of diocese was ever devised and few systematic attempts were made to achieve a degree of equity between them. The constitutional link between state and church has inhibited change for the last 80 years, although society has changed significantly. Nevertheless, rapid constitutional reforms, especially in the House of Lords, may be reflected in ecclesiastical reorganisation of the dioceses.
Anthony John ChristopherEmail:
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12.
Substantial progress has been made within central Arizona in moving towards a more sustainable water future, particularly in transitioning the urban demand from a primarily nonrenewable groundwater-based supply to increasing dependence on the Colorado River, Salt River and effluent. Management efforts include a wide range of regulatory and voluntary programs which have had mixed success. The Department of Water Resources has learned a number of key lessons throughout the years, and this paper attempts to establish the water management context and identify those lessons for the benefit of others who may want to evaluate alternative approaches to groundwater management. Themes to be discussed include evaluating water management approaches in a public policy context, the effectiveness of alternative management approaches and the relative merits of regulatory vs. nonregulatory efforts, and the importance of high-quality data in making management decisions.
James M. HolwayEmail:
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13.
Summary  The question of alternative technologies for high-speed Internet access lies at the heart of rural development problems. In this paper, we focus on one of those technologies, the system combining satellite technologies and Wi-Fi. Based on an empirical study carried out in three rural areas, we analyze the dynamics of the use and appropriation of that technology by the companies and organizations participating in the experiment. Considered both from a technical and social standpoint, the technology ‘in use’ appears here in its structuring dimensions.
Valérie FautreroEmail:
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14.
The paper compares the results of two studies of salt damage at the Wakefield Tower, Tower of London. The first, in 1993, was based on semi-quantitative salt analysis and hygroscopicity measurements. The second was based on quantitative analysis and a thermodynamic model, ECOS. Both studies aimed to predict environmental conditions that would minimise salt damage to the interior stonework. Their predictions are markedly different, and this paper examines the reasons for the differences. It is shown that hygroscopicity alone is not a reliable indicator of crystallisation from mixed salt solutions.
Clifford A. PriceEmail:
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15.
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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16.
Approximately 1.2 km of dolomitic limestone overlies the Far West Rand gold reefs southwest of Johannesburg, South Africa. This karst aquifer is partitioned into several groundwater compartments by predominantly north–south trending syenite dykes. Prior to mining, the primary water flow was westwards, decanting over dyke boundaries as a succession of springs along the Lower Wonderfontein Spruit. Dewatering of the overlying dolomitic aquifer for safety and economic reasons by deep gold mining operations, caused the water levels of four compartments to drop and their respective springs to dry up. By perforating dykes, formerly separated aquifers were hydraulically interconnected by mining. Using historical and recent data of water flow—surface and groundwater—and pumping rates, a geohydrological model is presented. The results suggest that the water tables will rise to their pre-mining levels within 30 years after mining ceases and that the dry springs will flow again, despite the compartments being connected by the extensive mining operations.
C. J. U. SwartEmail: Phone: +27-18-7874435Fax: +27-18-7875972
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17.
Historically, rights in water originated as public property and only later became individualized rights to utilize the public resource, in a manner consistent with the public welfare needs of society, but protected by principles of property law. Five basic regulatory systems for rights in groundwater in the United States have evolved to date. The problems raised by the hydrologic differences between groundwater hydraulically connected to stream systems and groundwater in non-replenished aquifers have been resolved to some extent by a couple of leading court cases. Numerical modeling and other technical methodologies have also evolved to evaluate the scientific issues raised by the different hydrologic conditions, but these are not immune from criticism. The current role of aquifers is evolving into that of storage facilities for recycled water, and their utilization in this manner may be expanded even further in the future. The policy implications of the choices relating to joint management of ground and surface water cannot be overstated. As this paper demonstrates, proactive administration of future groundwater depletions that affect stream systems is essential to the ultimate ability to plan for exploitation, management and utilization of water resources in a rational way that coordinates present and future demand with the reality of scarcity of supply. The examples utilized in this paper demonstrate the need for capacity building, not just to develop good measurement techniques, or to train talented lawyers and judges to write good laws, but also for practical professional water managers to keep the process on a rational course, avoiding limitless exploitation of the resource as well as conservative protectionism that forever precludes its use.
Charles T. DuMarsEmail: Phone: +1-505-3460998Fax: +1-505-3460997
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18.
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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19.
A study of erosion rates by in-situ 10Be concentrations in granites of Miocene high-elevation paleosurfaces in Corsica indicates maximum erosion rates between 8 and 24 mm/kyear. The regional distribution of measured erosion rates indicates that the local climatic conditions, namely precipitation, the petrographic composition of granites, and the degree of brittle deformation govern erosion rates. Chemical erosion dominates even at elevations around 2,000 m in presently subalpine climate conditions. Field evidence indicates that erosion operates by continuous dissolution and/or disintegration to grains (grusification). The erosion rates are relatively high with respect to the preservation of inferred Early Miocene landscapes. We infer temporal burial in the Middle Miocene and significantly lower erosion rates in the Neogene until ∼3 Ma to explain the preservation of paleosurfaces, in line with fission track data. Valley incision rates that are a magnitude higher than erosion rates on summit surfaces result in relief enhancement and long-term isostatic surface uplift. On the other hand, widening and deepening of valleys by cyclic glaciation progressively destroys the summit surface relics.
Wolfgang FrischEmail:
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20.
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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