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Geographic Information System for the Evaluation of Groundwater Pollution Vulnerability of the Northwestern Barind Tract of Bangladesh
Shamsuddin Shahid,Manzul Kumar Hazarika
Environmental Research Journal , 2012,
Abstract: Groundwater is the main source of drinking in the northwestern Barind region of Bangladesh. Therefore, prevention of this resource to pollution is crucial to avoid probable health and environmental hazards. An attempt has been taken in this study to map the vulnerability of the groundwater resource to contamination based on a multi-criteria approach known as DRASTIC within a geographic information system. Seven thematic maps of DRASTIC parameters are developed from available soil, borehole litholog, groundwater fluctuations and elevation model data of the region. The maps are integrated within geographic information system to generate the maps of groundwater vulnerability to both agricultural pollutants and general pollutants. The pollution vulnerability maps are validated with existing groundwater quality data. The result shows that almost 38.1% of the area is highly vulnerable to agricultural pollutants and 29.8% to general pollutants. Some management strategies are proposed for the protection of groundwater resource from pollution.
Groundwater Depletion with Expansion of Irrigation in Barind Tract: A Case Study of Tanore Upazila  [PDF]
Md. Marufur Rahman, A. Q. M. Mahbub
Journal of Water Resource and Protection (JWARP) , 2012, DOI: 10.4236/jwarp.2012.48066
Abstract: In this paper successive depletion of groundwater level with expansion of groundwater irrigation in Barind Tract has been discussed from mid 1960s to 2010 in the context of Tanore Upazila, which is located in severely drought prone area of northwest Bangladesh. After starting of groundwater irrigation in Bangladesh, it spread rapidly all over the country, and about 80% of agricultural land is now supplied irrigation from groundwater. Availability of irrigation in Barind Tract has revolutionized its agriculture, but groundwater level is successively falling all over the country due to excessive withdrawal, and this process is accelerating due to water withdrawal from major rivers by upstream countries. In northwestern part of Bangladesh groundwater depletion problem is severe because this part is free from seasonal flooding. Only source of recharging of groundwater aquifer in this area is rainfall, but rainfall is also lowest here among the country. In this context, this paper presents the change of groundwater level with the spreading of groundwater irrigation in Barind Tract. Hydrograph analysis, groundwater level mapping, groundwater depletion rate calculation are done from groundwater level observation well data of Bangladesh Water Development Board (BWDB) and Barind Multipurpose Development Authority (BMDA). Climatic condition is analyzed by calculation of rainfall deviation from the data of Bangladesh Meteorological Department (BMD). Focus Group Discussion (FGD) and interviews with farmers and experts of different branches are conducted to understand the nature of problems in the study area. Agricultural pattern, cropping intensity (262% in study area and national intensity is 180%), methods of cultivation, crop variety and yields all show a positive change after starting of groundwater irrigation in mid 1980s, but water level is continuously lowering at the rate of 1.37 ft/y in wet season and 0.72 ft/y in dry season. Water is the main input for agriculture but successive depletion of groundwater level can be a serious problem for water stressed Barind Tract. Crop diversification, artificial recharging, increasing dependency on surface water, increasing irrigation efficiency, rainwater harvesting etc., can be option for the area.
Screeningof Endangered Medicinal Plants Species by Questionnaire Survey in Barind Tract in Bangladesh  [PDF]
N.A. Siddique,M.A. Bari,M.M. Pervin,N. Nahar
Pakistan Journal of Biological Sciences , 2005,
Abstract: This study deals with over two hundred medicinal plants of ethnobotanical importance, used by the village doctors especially village Kavirajs in Barind Tract for medicinal purposes. This study aims at the identification of endangered medicinal plants by questionnaire survey and also preservation and perpetuation of this knowledge of the local plants possessing medicinal properties for the benefit and further fruitful investigation on modern scientific lines.
Collection of Indigenous Knowledge and Identification of Endangered Medicinal Plants by Questionnaire Survey in Barind Tract of Bangladesh  [PDF]
N.A. Siddique,M.A. Bari,A.T.M. Naderuzzaman,N. Khatun
Journal of Biological Sciences , 2004,
Abstract: This paper deals with over one hundred plants of ethnobotanical importance, used by the village doctors especially village kaviraj of Barind Tract for medicinal purposes.This work aims at the preservation and perpetuation of this knowledge of the local plants possessing medicinal properties for the benefit and further fruitful investigation on modern scientific lines and also identification of endangered medicinal plants by questionnaire survey.The data presented in this paper has been collected by personal contact with the local people and herbal practitioners, obtaining the information with great difficulty because of their recticence in divulging the secret of the identity of plants of great traditional reputation.
Lithological Study and Mapping of Barind Tract Using Borehole Log Data with GIS: In the Context of Tanore Upazila  [PDF]
Md. Marufur Rahman, A. Q. M. Mahbub
Journal of Geographic Information System (JGIS) , 2012, DOI: 10.4236/jgis.2012.44040
Abstract: In this paper the lithological study and mapping of Barind Tract is done by using irrigation boreholes log data in the context of an upazila under Barind Tract in northwest Bangladesh. Northwestern part of Bangladesh is severely drought prone area with lowest yearly rainfall in the country. Before groundwater irrigation only one crop was cultivated in this area in rainy season. After spreading of groundwater irrigation agriculture is flourished here, but groundwater level is severely going down, which is making this area risky for several adverse effect like land subsidence, biodiversity loss etc. Lithology is one of the important factors that affect the recharging of groundwater aquifer of any area. This research mainly based on secondary data. Irrigation boreholes log data are collected from Barind Multipurpose Development Authority (BMDA), a local authority under the Ministry of Agriculture of Bangladesh government provide irrigation in Barind Tract. A GPS survey is conducted to locate the boreholes in the study area. From the study highest thickness of clay layer found 90 ft and lowest 20 ft, and thickness gradually increase from eastern to western side. Aquifer is located between 20 - 90 ft depth from the surface and direction of aquifer is western to eastern side. Agriculture of study area is totally dependent on groundwater irrigation. Thick layer of clay impede recharging of groundwater table. Due to thick layer of sticky and plastic clay land subsidence risk is low, but it act as aquitard which impede groundwater recharging and increase surface runoff.
Optimal and Sustainable Groundwater Extraction  [PDF]
James A. Roumasset,Christopher A. Wada
Sustainability , 2010, DOI: 10.3390/su2082676
Abstract: With climate change exacerbating over-exploitation, groundwater scarcity looms as an increasingly critical issue worldwide. Minimizing the adverse effects of scarcity requires optimal as well as sustainable patterns of groundwater management. We review the many sustainable paths for groundwater extraction from a coastal aquifer and show how to find the particular sustainable path that is welfare maximizing. In some cases the optimal path converges to the maximum sustainable yield. For sufficiently convex extraction costs, the extraction path converges to an internal steady state above the level of maximum sustainable yield. We describe the challenges facing groundwater managers faced with multiple aquifers, the prospect of using recycled water, and the interdependence with watershed management. The integrated water management thus described results in less water scarcity and higher total welfare gains from groundwater use. The framework also can be applied to climate-change specifications about the frequency, duration, and intensity of precipitation by comparing before and after optimal management. For the case of South Oahu in Hawaii, the prospect of climate change increases the gains of integrated groundwater management.
ASSESSMENT OF GROUNDWATER QUALITY IN SUNAMGANJ OF BANGLADESH  [PDF]
F. Raihan, J. B. Alam
Iranian Journal of Environmental Health Science & Engineering , 2008,
Abstract: In this study, groundwater quality in Sunamganj of Bangladesh was studied based on different indices for irrigation and drinking uses. Samples were investigated for sodium absorption ratio, soluble sodium percentage, residual sodium carbonate, electrical conductance, magnesium adsorption ratio, Kelly's ratio, total hardness, permeability index, residual sodium bi-carbonate to investigate the ionic toxicity. From the analytical result, it was revealed that the values of Sodium Adsorption Ratio indicate that ground water of the area falls under the category of low sodium hazard. So, there was neither salinity nor toxicity problem of irrigation water, so that ground water can safely be used for long-term irrigation. Average Total Hardness of the samples in the study area was in the range of between 215 mg/L at Tahirpur and 48250 mg/L at Bishamvarpur. At Bishamvarpur, the water was found very hard. Average total hardness of the samples was in the range of between 215 mg/L at Tahirpur and 48250 mg/L at Bishamvarpur. At Bishamvarpur, the water was found very hard. It was shown based on GIS analysis that the groundwater quality in Zone-1 could be categorized of "excellent" class, supporting the high suitability for irrigation. In Zone-2 and Zone-3, the groundwater quality was categorized as "risky" and "poor" respectively. The study has also made clear that GIS-based methodology can be used effectively for ground water quality mapping even in small catchments.
Recent trends in groundwater levels in a highly seasonal hydrological system: the Ganges-Brahmaputra-Meghna Delta
M. Shamsudduha, R. E. Chandler, R. G. Taylor,K. M. Ahmed
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2009,
Abstract: Groundwater levels in shallow aquifers underlying Asian mega-deltas are characterized by strong seasonal variations associated with monsoon rainfall. To resolve trend and seasonal components in weekly groundwater levels in the Ganges-Brahmaputra-Meghna (GBM) Delta, we apply a nonparametric seasonal-trend decomposition procedure (STL) to observations compiled from 1985–2005 in Bangladesh. Seasonality dominates observed variance in groundwater levels but declining groundwater levels (>1 m/yr) are detected in urban and peri-urban areas around Dhaka as well as in north-central, northwestern, and southwestern parts of the country (0.1–0.5 m/yr) where intensive abstraction of groundwater is conducted for dry-season rice cultivation. Rising groundwater levels (0.5–2.5 cm/yr) are observed in the estuarine and southern coastal regions. This novel application of the STL procedure reveals, for the first time, the unsustainability of irrigation supplied by shallow aquifers in some areas (e.g., High Barind Tract) of the GBM Delta and the hydrological impact of potential seawater intrusion of coastal aquifers associated with sea-level rise. Our findings provide important insight into the hydrological impacts of groundwater-fed irrigation and sea-level rise in other Asian mega-deltas where monitoring data are limited.
Assessment of Arsenic Contamination of Groundwater and Health Problems in Bangladesh  [PDF]
Md. Khalequzzaman,Fazlay S. Faruque,Amal K. Mitra
International Journal of Environmental Research and Public Health , 2005, DOI: 10.3390/ijerph2005020002
Abstract: Excessive amounts of arsenic (As) in the groundwater in Bangladesh and neighboring states in India are a major public health problem. About 30% of the private wells in Bangladesh exhibit high concentrations of arsenic. Over half the country, 269 out of 464 administrative units, is affected. Similar problems exist in many other parts of the world, including the Unites States. This paper presents an assessment of the health hazards caused by arsenic contamination in the drinking water in Bangladesh. Four competing hypotheses, each addressing the sources, reaction mechanisms, pathways, and sinks of arsenic in groundwater, were analyzed in the context of the geologic history and land-use practices in the Bengal Basin. None of the hypotheses alone can explain the observed variability in arsenic concentration in time and space; each appears to have some validity on a local scale. Thus, it is likely that several bio-geochemical processes are active among the region’s various geologic environments, and that each contributes to the mobilization and release of arsenic. Additional research efforts will be needed to understand the relationships between underlying biogeochemical factors and the mechanisms for arsenic release in various geologic settings.
Sustainable agriculture: a challenge in Bangladesh
M.A.A. Faroque
International Journal of Agricultural Research, Innovation and Technology : IJARIT , 2011,
Abstract: The sustainability of conventional agriculture in Bangladesh is under threat from the continuous degradation of land and water resources, and from declining yields due to indiscriminate use of agro-chemicals. Government is pursuing efforts to promote sustainable agriculture with emphasis on better use of on-farm resources and the reduction of external inputs. This paper presents four dimensions of agricultural sustainability as productivity, environmental stability, economical profitability, and social and economic equity. Six characters were selected to evaluate sustainability. Significant differences were found between the two systems (conventional and sustainable agriculture) in crop diversification, soil fertility management, pests and diseases management, use of agro-chemicals and environmental issues. However, no significant variations were found in other indicators such as land-use pattern, crop yield and stability, risk and uncertainties, and food security. Although crop yield and financial return were found to be slightly higher in the conventional system, the economic return and value addition per unit of land did not show any difference. It can be suggested that sustainable agriculture has a tendency towards becoming environmental, economically and socially more sound than conventional agriculture, as it requires considerably less agro-chemicals, adds more organic matter to the soil, provides balanced food, and requires higher local inputs without markedly compromising output and financial benefits. Broad-policy measures, including the creation of mass awareness of adverse health effects of agrochemical-based products, are outlined for the promotion of sustainable agriculture.
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