Intertemporal consumer behaviour in developing countries

This paper explores aggregate consumption behaviour in four developing countries under the assumption that consumers' planning horizons do not extend over their expected lifetime. Under certain conditions, the resulting ‘moving planning horizon model’ suggests that changes in current income would exert considerably more influence over current consumer spending than is predicted by forward-looking theories of consumption which typically assume that consumers' planning horizons coincide with expected lifetime. Estimation of the model for the group of developing countries provides empirical support for the role of changes in current income in influencing the consumption process. The results also reveal that consumers are relatively short-sighted sinced the length of the planning period of consumers ranges from just over ten months. An important implication of these findings is that policy measures can be effective not only if they influence consumers' permanent incomes but also if they affect changes in current income.     

Establishing Maintenance Resource Levels Using Selective Maintenance

We address the performance of a repairable system that is required to perform a sequence of equally spaced, identical missions with breaks between missions. The system is series-parallel in structure, and component repair can only be performed during breaks between missions. Due to limitations on maintenance resources, it may be impossible to make all necessary repairs before the next mission. Such situations require the use of selective maintenance, the process of identifying the subset of maintenance actions to perform from a set of desirable maintenance actions. We build upon previous research in selective maintenance by addressing decisions related to establishing capacities for the limited maintenance resources. We model mission-to-mission changes in maintenance resource capacity, and we develop a methodology for establishing constant resource capacities for a sequence of missions. Finally, we develop a methodology for integrating redundancy allocation and maintenance resource allocation decisions.     

Groundwater Rights and Legislation for Sustainable Development in Arid Regions: The Case of Saudi Arabia

The main objective of this article is to shed light on an important issue of water conservation-groundwater rights and legislation. Principles of groundwater rights are detailed and their applications to major aquifer systems, groundwater basins and wadis are discussed. Legislation and the clarification of water rights are vital for the sustainable development of groundwater. They are urgently needed in Saudi Arabia in particular and in all areas where demand exceeds supply. Legislation is one of the main pillars upon which any conservation policy is built. In this article a model is suggested for groundwater allocation in aquifers shared by more than one state.     

Generation of Daily and Hourly Weather Variables for use in Climate Change Vulnerability Assessment

This paper evaluates the impact of climate change, as projected by two Global Climate Models (GCMs) on the occurrence of extreme precipitation events in the Upper Thames River Basin in the Canadian province of Ontario. The modelling approach presented herein involves a two-stage process of generating daily weather data followed by disaggregation to an hourly time step of select variables for some events. Monthly change fields for three weather variables (maximum temperature, minimum temperature, and precipitation) were obtained from the output of two GCMs. The historical data set is modified by applying change fields to the weather variables simultaneously and then using this as the driving data set for an improved K-nearest neighbour weather-generating model. Weather sequences representative of climatic conditions in 2050 were simulated. Disaggregation of precipitation data is carried out using a new method that is a hybrid key site approach. A distinct practical advantage of the approach presented here is that extreme wet and dry spells are simulated, which is crucial for evaluation of effective flood and drought management policies for the basin.     

Temporal Hydrologic Alterations Coupled with Climate Variability and Drought for Transboundary River Basins

Climate change (CC) and drought episode impacts linked with anthropogenic pressure have become an increasing concern for policy makers and water resources managers. The current research presents a comprehensive methodology but simple approach for predicting the annual streamflow alteration based on drought indices and hydrological alteration indicators. This has been achieved depending on the evaluation of drought severity and CC impacts during the human intervention periods to separate the influence of climatic abnormality and measure the hydrologic deviations as a result of streamflow regulation configurations. As a representative case study, the Lesser Zab River Basin in northern Iraq has been chosen. In order to analyse the natural flow regime, 34 hydrological years of streamflow (1931–1965) prior to the main dam construction were assessed. The Indicators of Hydrologic Alteration (IHA) method has been applied to quantify the hydrological alterations of various flow characteristics. In addition, an easy approach for hydrological drought prediction in relatively small basins grounded on meteorological parameters during the early months of the hydrological year has been presented. The prediction was accomplished by implementing the one-dimensional drought examination and the reconnaissance drought index (RDI) for evaluating the severity of meteorological drought. The proposed methodology is founded on linear regression relations connecting the RDI of 3, 6, and 12 months and the streamflow drought index (SDI). The results are critical for circumstances where an early exploration of meteorological drought is obtainable. Outcomes assist water resources managers, engineers, policy makers and decision-makers responsible for mitigating the effects of CC.     

Evaluation of the pollution load discharged at an upstream industry--Egypt--and methods for its reduction

Oil exploration in Egypt is a major contributor to the national Gross Domestic Product (GDP). With 50-65% of the oil resources located in the Gulf of Suez (GoS) region, the impact of such activity upon the region's water environment and its quality cannot be overlooked because of the volume of effluent generated. The objective of this study (September 2000-September 2001) was to assess the impact of a 650,000 barrels/day (bl/d) (100,000 m3/d) effluent arising from a major oil exploration site located south of GoS upon the local water environment. Another objective was to identify the pollutant contents amenable for reduction relative to the new Egyptian regulations. This was achieved by the characterization of the main contributing streams and the identification of the final effluent parameter constraints relative to the type of injection waters used. Subsequent investigations for the reduction of these contents were conducted on site and the results obtained are reviewed herewith.     

Optimizing Approach of Water Allocation to Off-Takes During Reduced Flows

Multi-objective optimization models with an index were developed based on farmers’ preferences, local requirements, supplies available at the head of the canal, system losses, crop demand about different growth stages, and field soil moisture balance. The models were applied using linear programming. The Model 1 determines the cropping pattern by maximizing net economic benefits using a monthly basis lumped volume available at the head of the canal and is set to the minimum and maximum area constraints along with the constraint of minimum main crop area. The areas for different crops given by the first model form input for the Model 2. The other inputs of Model 2 included periodic supply available at the head of the primary canal (7-day period in this study), root growth depth, demand, and soil moisture constants. The Model 2 optimizes the sum of relative yields of all the crops and provide the irrigation levels of various crops for specified periods. Finally, the distributed area and irrigation levels determined by Model 2 are used in conjunction with the losses to decide flow rates of off takes. The complete program was implemented in the West branch irrigated area of Mirpurkhas subdivision. The results showed that the resources were allocated to off-takes in a competitive and conflict-free manner.

     

Assessment of Sustainable Yield of Karst Water in Huaibei,China

This paper presents the assessment of sustainable yield in the Huaibei karst water area of Anhui province, China. A review of sustainable yield definition is introduced first in this paper, and sustainable development in karst areas is more difficult due to the complicated hydrogeologic conditions. General hydrogeology of the study area is provided to characterize hydraulic connections between the karst aquifer and an overlying porous aquifer. Groundwater level declines continuously due to over-exploitation of the karst groundwater, and two layers of groundwater dropping funnel were formed in Huaibei. These problems not only threaten the eco-geo-environment, but also compromise the water utilization which depends on the shallow porous water. A “critical water level” is proposed in this study to assess the sustainable yield, and it is determined by the historical exploitation data which represent the relationship between the karst water and the shallow porous water uses. A three layer Artificial Neural Network (ANN) model is used to understand the complex relationship of the karst water level and its influencing factors. Precipitation, exploitation and water level of latest period are chosen as the input nodes, seasonal records of water level are simulated by the ANN model. The sustainable yield is calculated by the trail-and-error adjusting method, and is equal to the pumping rate when the “critical water level” is maintained. The rate of 30.05 MCM/a is the sustainable yield for the Huaibei karst area in 2008, and it is less than the real pumping rate of 35.92 MCM/a. This assessment is meaningful to the management for the Huaibei karst water.     

Global Financial Crisis: An African Perspective

This paper reviews the expanding financial turmoil that has been triggered by the Asian crisis. It examines the factors behind the crisis, its impact on African countries and the main lessons and policy implications for African countries. The onset of the Asian crisis seems to have taken everybody by surprise because the Asian countries that were hit by the crisis had been among the most successful in sustaining high rates of economic growth, keeping high saving and investment rates and improving the quality of life of their citizens. However, the emerging consensus is that the Asian crisis is a hybrid of structural and policy distortions (macro- and micro-economic) in the affected economies. The impact of the crisis on African countries was mainly transmitted through declines in export prices and volumes. The low demand for primary commodities induced by the crisis and the large depreciation of Asian currencies appear to have played major roles in depressing commodity prices. With only a few exceptions, the commodities that suffered large price declines are those for which Asia constitutes an important market (e.g. oil) and/or those mostly supplied by Asian countries (e.g. copper, timber and rubber). Africa’s oil-exporting countries, which experienced large deterioration in their terms of trade, were the most affected. For the continent as a whole, export proceeds declined by 9.5 per cent between 1997 and 1998. This was the product of a 7 per cent decline in export prices and a 2.5 per cent decline in the volume of exports. The paper estimates that the crisis has caused the growth rate in the region to slide down by 1.2 percentage points, which indicates a loss of US $6.2 billion using aggregate GDP for 1997 as the base. To put this in an order of magnitude, it is about US $2 billion higher than the annual average flow of FDI to the continent in recent years. For the majority of African countries where the inflow of private capital is small and where public debt is dominant, the traditional risk management policies, such as adopting realistic exchange rates and reducing government deficits and inflation rates, should continue to be major policy tools to prevent financial crisis. However, as the role of private capital increases the design of macroeconomic policies would need to heed the lessons emerging from Asia. One basic lesson is that careful sequencing of domestic and external liberalization is needed. In that, restrictions on the capital account, especially on the more volatile capital flows should be lifted only after the domestic financial sector has been strengthened with adequate regulatory and supervisory institutions. This is particularly true because the Asian crisis has shown that reserves, even at very high levels, can be quickly depleted given the scale and volatility of short-term capital flows. Le présent document analyse le développement de la tourmente financière déclenchée par la crise asiatique. Il examine les causes de cette crise, son impact sur les pays africains, les principaux enseignements à en tirer et ses incidences politiques pour l’Afrique. Le déclenchement de la crise asiatique semble avoir pris tout le monde de court. Les pays asiatiques touchés sont parmi ceux qui avaient enregistré des taux de croissance économique des plus élevés, maintenu des taux d’épargne et d’investissement des plus soutenus, et amélioré le plus la qualité de vie de leurs citoyens. Cependant, de l’avis général, la crise asiatique résulte de la conjonction de distorsions d’ordre structurels et politiques (macro et micro économiques) dans les pays touchés. Son impact sur les pays africains a été principalement ressenti é; travers la baisse des prix et du volume des exportations. Le fléchissement de la demande des produits de base et la forte dépréciation des monnaies asiatiques provoqués par la crise ont manifestement joué un rôle déterminant dans la chute des cours des produits de base. A quelques exceptions près, les produits dont les prix ont sensiblement baissé sont ceux pour lesquels l’Asie constitue un important marché (par exemple le pétrole) et/ ou ceux qui sont essentiellement fournis par les pays asiatiques (cuivre, bois, caoutchouc). Les pays africains exportateurs de pétrole, qui ont subi une détérioration marquée de leurs termes de l’échange, ont été les plus touchés. Pour l’ensemble du continent, les recettes d’exportation ont baissé de 9,5 pour cent entre 1997 et 1998. Cette situation résulte de la baisse de 7 pour cent des prix et de la contraction de 2,5 pour cent du volume des exportations. Ce document estime que la crise a entraîné un ralentissement de croissance de 1,2 point de pourcentage, soit une perte de 6,2 milliards de dollars EU, si l’on utilise comme base le PIB global de 1997. Traduit en ordre de grandeur, ce chiffre est d’environ 2 milliards de dollars supérieur au montant des flux moyens annuels d’IDE obtenus par le continent au cours de ces dernières années. Pour la majorité des Etats africains oú l’apport de capitaux privés est faible, et la dette publique écrasante, les politiques traditionnelles de gestion de risque, comme l’adoption de taux de change réalistes et la réduction des déficits publics et du taux d’inflation, doivent demeurer les principaux moyens d’action pour prévenir les crises financières. Cependant, à mesure qu’augmente le rôle des capitaux privés, la conception des politiques macroéconomiques devrait tenir compte des leçons qui se dégagent de l’expérience asiatique. La principale leçon est qu’il faut faire preuve de prudence dans la programmation de la libéralisation interne et externe. Dans cet esprit, la restriction des mouvements des capitaux, notamment ceux de capitaux les plus volatiles, ne doit être levée qu’après la consolidation du secteur financier au niveau interne avec le concours d’institutions compétentes de réglementation et de contrôle. Cette précaution est d’autant plus nécessaire que la crise asiatique a démontré que les réserves, même à des niveaux très élevés, peuvent s’épuiser rapidement du fait de l’ampleur et de la volatilité des flux des capitaux à court terme.