苏州地区地下水资源城市应急利用适宜性研究

随着太湖水体富营养化程度的不断加剧,建立安全、稳定、可靠的应急备用水源日益重要。利用2005~2009年苏州地区地下水水质连续监测和补充监测资料,对第Ⅱ承压含水层进行了应急利用(生活饮用和工业利用)的水质适宜性和安全性评价分析。研究结果表明:第Ⅱ承含水层主要水化学类型为Na-HCO3、Ca-HCO3和Na-CaHCO3型,水质总体稳定,年际差异很小;地下水水质指数(WQI)均值较低(位于49.98~68.75之间),地下水没有受到有机物污染,可作为应急利用水源;WQI的水质指标贡献率表明,As、Fe、pH和Mn指标的贡献率最大,局部区域As、Fe、Mn及氨氮和亚硝酸盐含量较高,应急利用时应进行处理。朗格里尔饱和指数(LSI)和拉森比(LnR)评价结果表明,该水源易结垢,具有轻微腐蚀倾向,作为工业备用水源时应进行适当的处理。为苏州地区地下水应急水源建设和安全利用提供了科学依据和参考。     

A study on the significance of lithology in groundwater quality of Madurai district, Tamil Nadu (India)

The groundwater occurs in hard rock aquifers, which is more predominant in India. It is more common in the southern peninsula especially Tamil Nadu. Madurai district is located in the central part of Tamil Nadu, underlain predominantly by crystalline formations and alluvium along the river course. The study area being a hard rock terrain, the groundwater is stored in cracks, fissures, joints, etc., and hence the quantity is lesser. The frequent failure of monsoon also aggravates the scarcity of this commodity. In this scenario, the quality and hydrogeochemistry of the available quantum of water plays a significant role for the determination of its utility and in tracing out the hydrogeochemical evaluation. Fifty-four groundwater samples were collected representing the entire study area. The samples collected were representative covering all the major litho units of the study area (charnockite -21, fissile hornblende biotite gneiss-21, granite-4, quartzite-3, and 5 samples from flood plain alluvium). The samples collected were analyzed for major ions and were classified for different purposes like drinking, domestic, and agriculture, with respect to lithology. The comparison of the groundwater samples with the drinking water standards shows that few samples fall above the drinking water limit irrespective of lithology. The samples were classified with sodium absorption ratio, electrical conductivity, residual sodium carbonate, sodium percentage (Na %), Kellys ratio, and magnesium hazard, and permeability index for irrigation purpose found that most of the samples were suitable for irrigation purpose irrespective of lithology. Total hardness and corrosivity index were studied for the domestic purpose and found that the samples of the granitic terrain are safe. Apart from this, index of base exchange, Schoellers water type, Stuyfzands classification were attempted along with Gibbs plot to determine the major geochemical activity of the region. The study reveals that the samples collected from granitic and quartzitic terrains are comparatively better for the domestic and drinking purpose due to the presence of resistant minerals to weathering.     

Contamination of drinking water resources in the Mekong delta floodplains: arsenic and other trace metals pose serious health risks to population

This study presents a transnational groundwater survey of the 62,000 km(2) Mekong delta floodplain (Southern Vietnam and bordering Cambodia) and assesses human health risks associated with elevated concentrations of dissolved toxic elements. The lower Mekong delta generally features saline groundwater. However, where groundwater salinity is <1 g L(-)(1) Total Dissolved Solids (TDS), the rural population started exploiting shallow groundwater as drinking water in replacement of microbially contaminated surface water. In groundwater used as drinking water, arsenic concentrations ranged from 0.1-1340 microg L(-)(1), with 37% of the studied wells exceeding the WHO guidelines of 10 microg L(-)(1) arsenic. In addition, 50% exceeded the manganese WHO guideline of 0.4 mg L(-)(1), with concentrations being particularly high in Vietnam (range 1.0-34 mg L(-)(1)). Other elements of (minor) concern are Ba, Cd, Ni, Se, Pb and U. Our measurements imply that groundwater contamination is of geogenic origin and caused by natural anoxic conditions in the aquifers. Chronic arsenic poisoning is the most serious health risk for the ~2 million people drinking this groundwater without treatment, followed by malfunction in children's development through excessive manganese uptake. Government agencies, water specialists and scientists must get aware of the serious situation. Mitigation measures are urgently needed to protect the unaware people from such health problems.     

A Blue Economy for Aotearoa New Zealand?

Vandana Shiva has argued that the world is experiencing the triple crises of climate change, peak oil and increasing global food insecurity (Shiva 2008). A Green Economy, which focuses on a “low carbon, resource efficient and socially inclusive economy” (UNEP 2011, 16), has been viewed in some quarters as a way to begin combating the triple crises. In Aotearoa New Zealand, some of the local indigenous peoples Maori are looking at green opportunities, primarily in renewable energy production. Some scholars suggest, however, that the Green Economy should be combined with a Blue Economy. The Blue Economy, as explained by Gunter Pauli 2010, is one which focuses on nature and encourages companies and entrepreneurs to mimic nature in their processes and in the creation of their products. In this article, I suggest that considering a Blue Economy through the lens of a Maori worldview allows us to explore in another way the questions that the Blue Economy raises.     

Are sustainable cities “happy” cities? Associations between sustainable development and human well-being in urban areas of the United States

In this paper, we assess the associations between self-reported happiness, measured using the Gallup Healthways Well-Being Index (2012), and four US city sustainability indices: the Green City Index (2011), Our Green Cities (2012), Popular Science US City Rankings (2008) and the SustainLane US Green City Rankings (2007). Based on the examination of nonparametric, rank-based correlations, we found positive associations between sustainable development and happiness on all scales and statistically significant correlations for two of the four SD indices. Results support previous research, emphasize the value of explicit consideration of happiness when measuring urban sustainability and highlight the need for future research that assesses the influence of specific subsystems of urban development on self-reported happiness.     

Arsenic and other trace elements contamination in groundwater and a risk assessment study for the residents in the Kandal Province of Cambodia

Concentrations of arsenic and other trace elements in groundwater were examined at three villages (PT, POT and CHL) in the Kandal Province of Cambodia. Concentrations of arsenic in the groundwater ranged from 6.64 (in POT village) to 1543 microg/L (in PT village), with average and median concentrations of 552 and 353 microg/L, respectively. About 86% out of fifteen samples contained arsenic concentrations exceeding the WHO drinking water guidelines of 10 microg/L. Concentrations of arsenic (III) varied from 4 (in POT village) to 1334 microg/L (in PT village), with an average concentration of 470 microg/L. In addition, about 67%, 80% and 86% of the groundwater samples had higher concentrations for, respectively, barium, manganese and lead than the WHO drinking water guidelines. These results reveal that groundwater in Kandal Province is not only considerably contaminated with arsenic but also with barium, manganese and lead. A risk assessment study found that one sample (PT25) had a cumulative arsenic concentration (6758 mg) slightly higher than the threshold level (6750 mg) that could cause internal cancer in smelter workers with chronic exposure to arsenic from groundwater. High cumulative arsenic ingestion poses a health threat to the residents of Kandal Province.     

Multiscale system dynamics of humans and nature in The Bahamas: perturbation, knowledge, panarchy and resilience

The analysis of the dynamic interactions between social systems, integrated by governance and communication, and biophysical systems, connected by material and energy flows, remains a challenge. In this paper, we draw on the heuristic models of the “adaptive renewal cycle” and “panarchy” [Gunderson and Holling (eds) Panarchy: understanding transformations in human and natural systems. Island Press, Washington, 2002], which are embedded in the theory of complex adaptive systems. Taking island development research in The Bahamas as a case study, we investigate environmental stressors, knowledge and social response in the context of three distinct social–ecological subsystems: (1) the interaction between tropical storms/hurricanes and the social system of disaster preparedness/management; (2) coastal ecosystem degradation coupled with land development; and (3) the fishery, in which we also consider the impact of a recent biological invasion, the Indo-Pacific red lionfish. The findings demonstrate the complexity of panarchical relations and the crucial role of diverse and uncertain knowledge systems and underlying mental models of risk and environment for resilience and sustainability. These are acquired at different scales and form key variables of change. This also applies to processes of communication. Bringing together the various constantly evolving multi-level knowledge systems for effective communication and decision-making remains a major challenge.     

Inferring coastal processes from regional-scale mapping of Radon and salinity: examples from the Great Barrier Reef, Australia

The radon isotope ²²²Rn and salinity in coastal surface water were mapped on regional scales, to improve the understanding of coastal processes and their spatial variability. Radon was measured with a surface-towed, continuously recording multi-detector setup on a moving vessel. Numerous processes and locations of land-ocean interaction along the Central Great Barrier Reef coastline were identified and interpreted based on the data collected. These included riverine fluxes, terrestrially-derived fresh submarine groundwater discharge (SGD) and the tidal pumping of seawater through mangrove forests. Based on variations in the relationship of the tracers radon and salinity, some aspects of regional freshwater inputs to the coastal zone and to estuaries could be assessed. Concurrent mapping of radon and salinity allowed an efficient qualitative assessment of land-ocean interaction on various spatial and temporal scales, indicating that such surveys on coastal scales can be a useful tool to obtain an overview of SGD locations and processes.     

江苏盐城地区地下水水化学特征及形成机理

为了查明江苏盐城地区深层地下水咸化的主要影响因素,采集了不同类型水样(河水、浅层地下水、深层地下水和海水),通过对该地区不同水体的水化学特征、离子比值以及氘氧氚同位素组成进行分析,研究了盐城地区深层地下水水化学特征的形成机理。结果表明:浅层微咸水主要是溶解地层盐分和蒸发作用形成,而滨海港镇的部分地区受到一定程度的现代海水入侵影响。深层地下水总体为淡水,水化学演化以正常的水-岩作用为主,而深层微咸水主要分布在两个地区,一是东部滨海地区的灌河口至大丰一带,二是内陆地区的大丰市及其周边一带。滨海地区的深层微咸水主要是淋滤古海相地层盐分形成,黄沙港镇部分地区则受到轻微的现代海水入侵影响,而内陆地区的深层微咸水主要是浅层咸水下渗造成的。因此,盐城东部沿海矿化度增高的区域应大力加强对地下水的保护,特别是随着全球变暖,黄海海平面有上升的趋势,东部的滨海港镇等受海水入侵影响较大的区域更应引起高度重视。     

Assessing groundwater quality and its sustainability in Joypurhat district of Bangladesh using GIS and multivariate statistical approaches

Sustainable groundwater quality is a key global concern and has become a major issue of disquiets in most parts of the world including Bangladesh. Hence, the assessment of groundwater quality is an important study to ensure its sustainability for various uses. In this study, a combination of multivariate statistics, geographical information system (GIS) and geochemical approaches was employed to evaluate the groundwater quality and its sustainability in Joypurhat district of Bangladesh. The results showed that the groundwater samples are mainly Ca–Mg–HCO₃ type. Principal component analysis (PCA) results revealed that geogenic sources (rock weathering and cation exchange) followed by anthropogenic activities (domestic sewage and agro-chemicals) were the major factors governing the groundwater quality of the study area. Furthermore, the results of PCA are validated using the cluster analysis and correlation matrix analysis. Based on the groundwater quality index (GWQI), it is found that all the groundwater samples belong to excellent to good water quality domains for human consumption, although iron, fluoride and iodide contaminated to the groundwater, which do not pose any significant health hazard according to World Health Organization’s and Bangladesh’s guideline values. The results of irrigation water quality index including sodium adsorption ratio (SAR), permeability index and sodium percentage (Na %) suggested that most of the groundwater samples are good quality water for agricultural uses. The spatial distribution of the measured values of GWQI, SAR, Fe (iron), EC (electrical conductivity) and TH (total hardness) were spatially mapped using the GIS tool in the study area.     

Salinity evolution of the Tigris River

Major modifications regulating the Tigris River, originated in the 1940s and continuing to the present, have resulted in changes in salinity in the system over time and in different portions of the river course. The increase in salinity is due to decreases in stream discharge due to dams, water management structures such as the Lake Tharthar system, irrigation return flow, and soluble minerals in the basin. This research documents the increase and evaluates the causes of the salinity increase of the river from predevelopment to present using published and previously unavailable data. The predevelopment salinity was under 600 ppm, since 1984 has exceeded the 1000 ppm threshold recommended for drinking water downstream of Amara. A minimum instream flow for the river is calculated at Baghdad and Kut at 185 cubic meters per second (cms), approximately 15% of the mean historical flow of the river, but above the lowest minimum flow recorded at 140 cms. Recommended salinity management options discussed include (1) eliminating Lake Tharthar as a water storage facility, (2) managing saline inflows from tributaries, and (3) employing a minimum instream flow for the river.     

A linear and nonlinear approach for interpretation of groundwater quality based on water quality index

In this study using linear and nonlinear approach, aggregate indices for various water quality parameters were analyzed. Using a linear and nonlinear interpolating surface, various water quality variables at grid points were investigated that is essential for mapping. The values help in constituting a key approach for determining the water quality index (WQI), which converts pollutant concentration data into subindex values and then combines them into a single score. One of the biggest advantages of WQI is its summary and intuitive communication capability which will be extremely helpful for demarcating safe aquifer zones of groundwater and in the selection of suitable method for remedial. The present study also describes pollution potential in ground water of Madhya Pradesh, India. The aggregate indices suggest intermediate to high pollution susceptibility in some region of Madhya Pradesh that may increase further if not managed. The overall interpretation of the study will be helpful in formulating suitable approach for water quality interpretation and sustainable planning of groundwater resources.     

Awareness on usage of contaminated groundwater around Perungudi dumpsite,Tamil Nadu,India

Groundwater is the major drinking water source both in urban and rural area. Mostly in urban and peri-urban areas of developing countries, groundwater is more susceptible to contamination due to urbanization. Therefore, the awareness of usage of groundwater has to be analysed to frame the policy measures and to suggest proper intervention programs. The community residing around Perungudi dumpsite, Tamil Nadu, India, has been chosen to assess the awareness on usage of groundwater using regression model. The groundwater flow and quality analysis assessed technically is in line with people’s perception on groundwater quality. The model results clearly indicate that the socio-economic status (β = 0.167) and distance (β = 0.305) play a major role in groundwater usage. Though 31.2 % of respondents reported that the water quality is bad within 1 km in the contaminated area, 45 % of low socio-economic categories depend on well water. This shows the unawareness of health issues due to the usage of contaminated water. Proper policies have to be framed, especially for the contaminated site to get rid of adverse health impacts due to long-term exposure of contaminated water.     

Groundwater in the Limpopo Basin: occurrence,use and impact

The Limpopo River Basin is underlain by an alluvial aquifer along the main river stem and fractured water-bearing units in tributary catchments. Notwithstanding that development priorities in parts of the basin in South Africa have historically preferred surface water sources for irrigation and domestic supply, water resources auditing suggests that groundwater presents the only viable alternative source of cost-effective supply to meet future requirements. However, while aquifer yields are favourable in places, averaging 16.7 l/s for main-stem alluvium, groundwater is already extensively used. Between 1995 and 2002, total groundwater use in the area rose by almost 40%, increasing from 98 to 136 million m³ per year. In all catchments, groundwater use grew by varying proportions, reaching a rather high 200% in the Mogalakwena catchment. In the particular case of commercial irrigation, over-exploitation of groundwater has been recorded in a number of places, especially in the northwest where drawdowns of more than 50 m have resulted from decades of intense agricultural water use. Although groundwater use for mining is still low at 4% of total usage in the study area, the region is currently witnessing a surge in mining operations, and a significant growth in water requirements is envisaged for mining development. Further, domestic water supply to the predominantly rural dwellers in the area is relatively low, even in terms of meeting the basic need of 25 l/day per person, underscoring the fact that groundwater will remain a critical source of community drinking water in the foreseeable future. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Groundwater quality and its health impact: An assessment of dental fluorosis in rural inhabitants of the Main Ethiopian Rift

This study aims to assess the link between fluoride content in groundwater and its impact on dental health in rural communities of the Ethiopian Rift. A total of 148 water samples were collected from two drainage basins within the Main Ethiopian Rift (MER). In the Ziway–Shala basin in particular, wells had high fluoride levels (mean: 9.4 ± 10.5 mg/L; range: 1.1 to 68 mg/L), with 48 of 50 exceeding the WHO drinking water guideline limit of 1.5 mg/L. Total average daily intake of fluoride from drinking groundwater (calculated per weight unit) was also found to be six times higher than the No-Observed-Adverse-Effects-Level (NOAEL) value of 0.06 mg/kg/day. The highest fluoride levels were found in highly-alkaline (pH of 7 to 8.9) groundwater characterized by high salinity; high concentrations of sodium (Na⁺), bicarbonate (HCO₃⁻), and silica (SiO₂); and low concentrations of calcium (Ca^2 +). A progressive Ca^2 + decrease along the groundwater flow path is associated with an increase of fluoride in the groundwater. The groundwater quality problem is also coupled with the presence of other toxic elements, such as arsenic (As) and uranium (U). The health impact of fluoride was evaluated based on clinical examination of dental fluorosis (DF) among local residents using the Thylstrup and Fejerskov index (TFI). In total, 200 rural inhabitants between the ages of 7 and 40 years old using water from 12 wells of fluoride range of 7.8–18 mg/L were examined. Signs of DF (TF score of ≥ 1) were observed in all individuals. Most of the teeth (52%) recorded TF scores of 5 and 6, followed by TF scores of 3 and 4 (30%), and 8.4% had TF scores of 7 or higher. Sixty percent of the teeth exhibited loss of the outermost enamel. Within the range of fluoride contents, we did not find any correlation between fluoride content and DF. Finally, preliminary data suggest that milk intake has contributed to reducing the severity of DF. The study highlights the apparent positive role of milk on DF, and emphasizes the importance of nutrition in management efforts to mitigate DF in the MER and other parts of the world.     

Co-evolution of wetland landscapes,flooding, and human settlement in the Mississippi River Delta Plain

River deltas all over the world are sinking beneath sea-level rise, causing significant threats to natural and social systems. This is due to the combined effects of anthropogenic changes to sediment supply and river flow, subsidence, and sea-level rise, posing an immediate threat to the 500–1,000 million residents, many in megacities that live on deltaic coasts. The Mississippi River Deltaic Plain (MRDP) provides examples for many of the functions and feedbacks, regarding how human river management has impacted source-sink processes in coastal deltaic basins, resulting in human settlements more at risk to coastal storms. The survival of human settlement on the MRDP is arguably coupled to a shifting mass balance between a deltaic landscape occupied by either land built by the Mississippi River or water occupied by the Gulf of Mexico. We developed an approach to compare 50 % L:W isopleths (L:W is ratio of land to water) across the Atchafalaya and Terrebonne Basins to test landscape behavior over the last six decades to measure delta instability in coastal deltaic basins as a function of reduced sediment supply from river flooding. The Atchafalaya Basin, with continued sediment delivery, compared to Terrebonne Basin, with reduced river inputs, allow us to test assumptions of how coastal deltaic basins respond to river management over the last 75 years by analyzing landward migration rate of 50 % L:W isopleths between 1932 and 2010. The average landward migration for Terrebonne Basin was nearly 17,000 m (17 km) compared to only 22 m in Atchafalaya Basin over the last 78 years (p < 0.001), resulting in migration rates of 218 m/year (0.22 km/year) and <0.5 m/year, respectively. In addition, freshwater vegetation expanded in Atchafalaya Basin since 1949 compared to migration of intermediate and brackish marshes landward in the Terrebonne Basin. Changes in salt marsh vegetation patterns were very distinct in these two basins with gain of 25 % in the Terrebonne Basin compared to 90 % decrease in the Atchafalaya Basin since 1949. These shifts in vegetation types as L:W ratio decreases with reduced sediment input and increase in salinity also coincide with an increase in wind fetch in Terrebonne Bay. In the upper Terrebonne Bay, where the largest landward migration of the 50 % L:W ratio isopleth occurred, we estimate that the wave power has increased by 50–100 % from 1932 to 2010, as the bathymetric and topographic conditions changed, and increase in maximum storm-surge height also increased owing to the landward migration of the L:W ratio isopleth. We argue that this balance of land relative to water in this delta provides a much clearer understanding of increased flood risk from tropical cyclones rather than just estimates of areal land loss. We describe how coastal deltaic basins of the MRDP can be used as experimental landscapes to provide insights into how varying degrees of sediment delivery to coastal deltaic floodplains change flooding risks of a sinking delta using landward migrations of 50 % L:W isopleths. The nonlinear response of migrating L:W isopleths as wind fetch increases is a critical feedback effect that should influence human river-management decisions in deltaic coast. Changes in land area alone do not capture how corresponding landscape degradation and increased water area can lead to exponential increase in flood risk to human populations in low-lying coastal regions. Reduced land formation in coastal deltaic basins (measured by changes in the land:water ratio) can contribute significantly to increasing flood risks by removing the negative feedback of wetlands on wave and storm-surge that occur during extreme weather events. Increased flood risks will promote population migration as human risks associated with living in a deltaic landscape increase, as land is submerged and coastal inundation threats rise. These system linkages in dynamic deltaic coasts define a balance of river management and human settlement dependent on a certain level of land area within coastal deltaic basins (L).     

Monitoring and evaluation of shallow well water quality near a waste disposal site

This study identifies shallow well water contamination sources near the Mae-Hia waste disposal site and the clarification of the extent of well water contamination caused by leachate generated from the disposal site. The water of 40 shallow wells around the Mae-Hia disposal site, where three potential sources of groundwater pollution exist, was sampled and analyzed for physical, chemical, and biological characteristics. Water samples were taken every month from June 1989 to May 1990 along with a measurement of well water levels in order to estimate the groundwater flow direction. Comparison with the drinking water standards/guidelines showed that well water in the study area was not suitable for drinking due to the high contamination of total and fecal coliforms and moderate contamination by nitrate and manganese. It was found that the level of conductivity, total solids, color, chloride, chemical oxygen demand, sodium, copper, and lead in the groundwater of wells located adjacent to the disposal site were higher than in other areas. In addition, higher concentrations of sodium, chloride, calcium, and magnesium in the wells located downstream of the groundwater flow were recorded. Estimation of a leachate plume using chloride as an indicator showed that the wells located in the eastern part of the disposal site, a dominant direction of groundwater flow, were contaminated by leachate generated from the waste disposal site.     

Reuse of mining wastewater in agricultural activities in Jordan

A pilot study was completed in the Al-Abyad area near phosphate mining activity in Jordan. Six plots of 50 m² each were planted with two types of plant species (Zea mays spp. and Medicago lupulina spp.) and irrigated using three types of water (fresh groundwater, mine wastewater, and hydride water consisting of 50% fresh and 50% mine wastewater) to investigate the suitability of utilizing mine wastewater for food production in the area. Water, soil and plant sampling was completed for each plot over different time intervals and analyzed for heavy metal (Cr⁺⁶, Ni⁺², Zn⁺² and Pb⁺²) in addition to major ionic composition of the water used for irrigation. Crop yield was estimated at the end of the experiment. Plots irrigated with mine wastewater showed slightly higher heavy metals concentrations and soil salinity during the experiment period was higher for plots irrigated with mine wastewater compared to plots irrigated with fresh water, and it was uniform through the upper 45 cm of the soil profile due to the high amount of irrigation water used during the experiment. Crop yield was inversely proportional to salinity as an increase of salinity by 2-folds resulted in reducing yield by almost 50%. However, no risk of heavy metals contamination was found in plants and soil. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

The scientific challenge of bridging the gap from the local to the earth system level: lessons from the study of mangroves and people in North Brazil

This article aims to address the challenges of sustainable earth system governance from a multi-scale level perspective. The local to regional system level reviews findings from a social–ecological system approach of a mangrove ecosystem in North Brazil. Seven challenges (Glaser et al. in Mangrove dynamics and management in North Brazil. Ecological studies series. Springer, Berlin, pp 307–388, 2010) that could provide relevant knowledge to society were identified. Their respective justification and recommendations are presented here. Further, these “challenges from the field” are linked and discussed with those challenges on earth system level elaborated by the International Council for Science in 2010. There it was stressed that sustainability problems are increasingly caused by drivers from multiple spatial and institutional levels in a single global human–nature system. The comparison between the global and local to regional challenges shows that most of these are reappearing disregarding the level of analysis, indicating that there is a universal core of global change problems. However, there are gaps visible which hamper the effective connections across the different spatial levels. These pertain to the subjects of knowledge generation and stakeholder inclusion. The final section elaborates on these recognized gaps and their science–policy dimensions. The article closes with the identification of a number of factors which currently impede global sustainability efforts: shortcomings in inter- and transdisciplinary research practice, lack of consistent structures for earth system governance and shortcomings in dealing with upscaling challenges whilst remaining locally relevant. A blueprint for a globally focused but regionally informed social–ecological analysis framework remains to be worked out.     

Impacts of arsenic contamination in groundwater: case study of some villages in Bangladesh

The contamination of groundwater in Bangladesh by arsenic is a widespread and serious environmental problem, affecting mainly the rural population who rely extensively on groundwater for drinking and cooking. The study conducted survey work in a few affected villages of the Northwest region in Bangladesh. The household survey gathered information on the respondents (affected by arsenic) water usage and sources, knowledge of the arsenic problem, changes in the source of water for drinking and cooking, arsenic mitigation technologies and socio-economic information on the households. The survey work shows that percentage of male patient is higher than female patient among the same level of household income in each study villages. Prevalence of arsenicosis is more among poorer sections and it is directly related to the poverty situation of the community. People know more about the health problems caused by arsenicosis but lack knowledge about mitigation aspects. In one of the study areas, every year an extra 4% tubewell is getting contaminated by arsenic. Arsenic contamination in groundwater also affects the environment and the ecology negatively. The NGOs have been found contributing to a knowledge creation process in the village community as the villagers are showing marked behavioral changes in water-use practice.