35 resultados para BANGLADESH GROUNDWATER

em Aston University Research Archive


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The thesis presents a two-dimensional Risk Assessment Method (RAM) where the assessment of risk to the groundwater resources incorporates both the quantification of the probability of the occurrence of contaminant source terms, as well as the assessment of the resultant impacts. The approach emphasizes the need for a greater dependency on the potential pollution sources, rather than the traditional approach where assessment is based mainly on the intrinsic geo-hydrologic parameters. The risk is calculated using Monte Carlo simulation methods whereby random pollution events were generated to the same distribution as historically occurring events or a priori potential probability distribution. Integrated mathematical models then simulate contaminant concentrations at the predefined monitoring points within the aquifer. The spatial and temporal distributions of the concentrations were calculated from repeated realisations, and the number of times when a user defined concentration magnitude was exceeded is quantified as a risk. The method was setup by integrating MODFLOW-2000, MT3DMS and a FORTRAN coded risk model, and automated, using a DOS batch processing file. GIS software was employed in producing the input files and for the presentation of the results. The functionalities of the method, as well as its sensitivities to the model grid sizes, contaminant loading rates, length of stress periods, and the historical frequencies of occurrence of pollution events were evaluated using hypothetical scenarios and a case study. Chloride-related pollution sources were compiled and used as indicative potential contaminant sources for the case study. At any active model cell, if a random generated number is less than the probability of pollution occurrence, then the risk model will generate synthetic contaminant source term as an input into the transport model. The results of the applications of the method are presented in the form of tables, graphs and spatial maps. Varying the model grid sizes indicates no significant effects on the simulated groundwater head. The simulated frequency of daily occurrence of pollution incidents is also independent of the model dimensions. However, the simulated total contaminant mass generated within the aquifer, and the associated volumetric numerical error appear to increase with the increasing grid sizes. Also, the migration of contaminant plume advances faster with the coarse grid sizes as compared to the finer grid sizes. The number of daily contaminant source terms generated and consequently the total mass of contaminant within the aquifer increases in a non linear proportion to the increasing frequency of occurrence of pollution events. The risk of pollution from a number of sources all occurring by chance together was evaluated, and quantitatively presented as risk maps. This capability to combine the risk to a groundwater feature from numerous potential sources of pollution proved to be a great asset to the method, and a large benefit over the contemporary risk and vulnerability methods.

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Historically, the study of corporate social responsibility (CSR) reporting has largely been within the context of Western economies. However, in the wake of highly publicized incidents such as Bhopal and the struggle of the Ogoni people in Nigeria, many large corporations now claim to be taking steps to improve their environmental and social performance within developing countries. Using the lens of stakeholder theory, this book examines whether the current practice of CSR reporting in developing countries is motivated by a desire to discharge accountability to all relevant stakeholders or whether it is being driven by the imperative of advancing corporate economic interests. While concepts like CSR reporting have become more fashionable, they vary widely in different national contexts; this book therefore clarifies the types and roles of CSR reporting and the underlying corporate motivations. The author considers the current CSR reporting practices in a number of developing countries, with particular attention given to illuminating a case study of Bangladesh.

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Although prior studies looked at corporate social disclosures (CSD hereafter) mainly from the managerial perspective there are very few studies which examined CSD from a non-managerial stakeholder perspective. This paper contributes to that limited CSD literature. It does so from a developing country perspective. The main aim of this paper is to examine the views of selected NGOs on current CSD practices in Bangladesh using Gramscian hegemonic analysis. For this purpose, semi-structured interviews were carried out in the selected social and environmental NGOs of both overseas and Bangladesh origin. The results suggest that NGOs viewed the current CSD practice as far from satisfactory. They also argued that it is mainly aimed at maintaining corporate interests of image building. The study suggests that it is not corporations to be blamed alone for production of CSD in the interests of business, it is the capitalist society that consents to such reproduction of CSD.

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Most environmental reporting studies have focused on developed countries. Only a handful number of studies are available on the developing countries, concentrating on the newly industrialized countries and African countries. No studies are available from South Asia except the widely quoted one of Singh and Ahuja (1983). Against this background, it is argued that an empirical study on environmental reporting practices in Bangladesh would make a significant contribution to the environmental reporting literature from the context of developing countries in general, and South Asian countries in particular. The study covers 30 recent annual reports of Bangladeshi companies relating to the year 1996. It shows that very limited environmental disclosure has been made. Although we have noted that 90% of companies made some environmental disclosures, the percentage of companies disclosing environmental information comes down to only 20 if we exclude disclosure related to expenditure on energy usage. In general, the quantity and the quality of disclosures seem to be inadequate and poor as compared to the environmental disclosures in the developed countries. The study concludes with an urge for further research in this regard.

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Most of the corporate social reporting (CSR) studies conducted so far have been in the context of developed countries. Very few studies are available on the CSR practices in developing countries. Given the different socio-economic context of developing countries it is argued that it is important to learn about the CSR practices in those countries. This study reports the results of a survey of CSR practices in Bangladesh. The main contribution of this paper is that in addition to measuring the extent and volume of disclosures by using content analysis, it explores the socio-political and economic context in which these disclosures take place.

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With the accelerating industrialization process, even further increasing population and mass deforestation, ‘sustainability’ as a concept has only recently been popularized in Bangladesh. This paper sheds light on the sustainable development process in Bangladesh. It points out the major challenges to this process and identifies the motivating factors for a sustainable society in Bangladesh. The paper concludes with some strategies that are considered essential for the development of a sustainable society in Bangladesh, e.g., strong and effective regulatory framework, emphasis on rural entrepreneurship, development of indigenous technology and an integrated environmental management system.

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Purpose – This paper seeks to respond to recent calls for more engagement-based studies of corporate social reporting (CSR) practice by examining the views of corporate managers on the current state of, and future prospects for, social reporting in Bangladesh. Design/methodology/approach – The paper uses a series of interviews with senior managers from 23 Bangladeshi companies representing the multinational, domestic private and public sectors. Findings – Key findings are that the main motivation behind current reporting practice lies in a desire on the part of corporate management to manage powerful stakeholder groups, whilst perceived pressure from external forces, notably parent companies' instructions and demands from international buyers, is driving the process forward. In the latter context it appears that adoption of international social accounting standards and codes is likely to become more prevalent in the future. Reservations are expressed as to whether such a passive compliance strategy is likely to achieve much in the way of real changes in corporate behaviour, particularly when Western developed standards and codes are imposed without consideration of local cultural, economic and social factors. Indeed, such imposition could be regarded as little more than an example of the erection of non-tariff trade barriers rather than representing any meaningful move towards empowering indigenous stakeholder groups. Originality/value – The paper contributes to the literature on CSR in developing countries where there is a distinct lack of engagement-based published studies.

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This paper aims to broaden the present CSR literature by extending its focus to the absence of CSR within a developing country, an area which, to date, is relatively under researched in comparison to the more widely studied presence of CSR within developed Western countries. In particular this paper concentrates upon the lack of disclosure on three particular eco-justice issues: child labour, equal opportunities and poverty alleviation. We critically examine why this is the case and thereby illuminate underlying motives behind corporate unwillingness to address these issues. For this purpose, 23 semi-structured interviews were undertaken with senior corporate managers in Bangladesh. The findings suggest that the main reasons for non-disclosure include lack of legal requirements, lack of knowledge/awareness, poor performance and fear of bad publicity. Given these findings the paper raises some serious concerns as to why corporations would ever be expected to voluntarily report on eco-justice issues where performance is poor and negative publicity would be generated. These significant issues require careful consideration by policy makers at the national, regional and international levels.

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Desalination of groundwater is essential in arid regions that are remote from both seawater and freshwater resources. Desirable features of a groundwater desalination system include a high recovery ratio, operation from a sustainable energy source such as solar, and high water output per unit of energy and land. Here we propose a new system that uses a solar-Rankine cycle to drive reverse osmosis (RO). The working fluid such as steam is expanded against a power piston that actuates a pump piston which in turn pressurises the saline water thus passing it through RO membranes. A reciprocating crank mechanism is used to equalise the forces between the two pistons. The choice of batch mode in preference to continuous flow permits maximum energy recovery and minimal concentration polarisation in the vicinity of the RO membrane. This study analyses the sizing and efficiency of the crank mechanism, quantifies energy losses in the RO separation and predicts the overall performance. For example, a system using a field of linear Fresnel collectors occupying 1000 m2 of land and raising steam at 200 °C and 15.5 bar could desalinate 350 m3/day from saline water containing 5000 ppm of sodium chloride with a recovery ratio of 0.7.

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In many areas of northern India, salinity renders groundwater unsuitable for drinking and even for irrigation. Though membrane treatment can be used to remove the salt, there are some drawbacks to this approach e.g. (1) depletion of the groundwater due to over-abstraction, (2) saline contamination of surface water and soil caused by concentrate disposal and (3) high electricity usage. To address these issues, a system is proposed in which a photovoltaic-powered reverse osmosis (RO) system is used to irrigate a greenhouse (GH) in a stand-alone arrangement. The concentrate from the RO is supplied to an evaporative cooling system, thus reducing the volume of the concentrate so that finally it can be evaporated in a pond to solid for safe disposal. Based on typical meteorological data for Delhi, calculations based on mass and energy balance are presented to assess the sizing and cost of the system. It is shown that solar radiation, freshwater output and evapotranspiration demand are readily matched due to the approximately linear relation among these variables. The demand for concentrate varies independently, however, thus favouring the use of a variable recovery arrangement. Though enough water may be harvested from the GH roof to provide year-round irrigation, this would require considerable storage. Some practical options for storage tanks are discussed. An alternative use of rainwater is in misting to reduce peak temperatures in the summer. An example optimised design provides internal temperatures below 30EC (monthly average daily maxima) for 8 months of the year and costs about €36,000 for the whole system with GH floor area of 1000 m2 . Further work is needed to assess technical risks relating to scale-deposition in the membrane and evaporative pads, and to develop a business model that will allow such a project to succeed in the Indian rural context.

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This work presents a two-dimensional approach of risk assessment method based on the quantification of the probability of the occurrence of contaminant source terms, as well as the assessment of the resultant impacts. The risk is calculated using Monte Carlo simulation methods whereby synthetic contaminant source terms were generated to the same distribution as historically occurring pollution events or a priori potential probability distribution. The spatial and temporal distributions of the generated contaminant concentrations at pre-defined monitoring points within the aquifer were then simulated from repeated realisations using integrated mathematical models. The number of times when user defined ranges of concentration magnitudes were exceeded is quantified as risk. The utilities of the method were demonstrated using hypothetical scenarios, and the risk of pollution from a number of sources all occurring by chance together was evaluated. The results are presented in the form of charts and spatial maps. The generated risk maps show the risk of pollution at each observation borehole, as well as the trends within the study area. This capability to generate synthetic pollution events from numerous potential sources of pollution based on historical frequency of their occurrence proved to be a great asset to the method, and a large benefit over the contemporary methods.