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1.
Sci Total Environ ; 703: 134760, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31744697

RESUMO

Pollution in rapidly urbanising cities and in delta systems is a serious problem that blights the lives and livelihoods of millions of people, damaging and restricting potable water supply and supplies to industry (Whitehead et al, 2015, 2018). Employing new technology based on luminescent molecular biosensors, the toxicity in the rivers around Dhaka in Bangladesh, namely the Turag, Tongi, Balu and Buriganga, has been assessed. Samples taken at 36 sites during medium and low flow conditions and during the Bishwa Ijtema Festival revealed high levels of cell toxicity, as well as high concentrations of metals, particularly aluminium, cadmium, chromium, iron, zinc, lithium, selenium and nickel. Chemical analysis also revealed low dissolved oxygen levels and anoxic conditions in the rivers at certain sites. The bacterial molecular biosensors were demonstrated to be fast, with results in 30 min, robust and a highly sensitive method for the assessment of water toxicity in the field. Furthermore, the biosensor toxicity analysis correlated with the metals data, and a multivariate regression relationship was developed relating toxicity to key metals, such a selenium, zinc and chromium. The resulting model has been validated against split samples and the Bishwa Ijtema Festival data. The combination of modelling and the molecular biosensor technology provides a new approach to detecting and managing pollution in urban river systems.


Assuntos
Técnicas Biossensoriais , Bangladesh , Cidades , Monitoramento Ambiental , Metais Pesados , Rios , Poluentes Químicos da Água
2.
Sci Total Environ ; 673: 218-229, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-30991313

RESUMO

The Mekong delta is recognised as one of the world's most vulnerable mega-deltas, being subject to a range of environmental pressures including sea level rise, increasing population, and changes in flows and nutrients from its upland catchment. With changing climate and socioeconomics there is a need to assess how the Mekong catchment will be affected in terms of the delivery of water and nutrients into the delta system. Here we apply the Integrated Catchment model (INCA) to the whole Mekong River Basin to simulate flow and water quality, including nitrate, ammonia, total phosphorus and soluble reactive phosphorus. The impacts of climate change on all these variables have been assessed across 24 river reaches ranging from the Himalayas down to the delta in Vietnam. We used the UK Met Office PRECIS regionally coupled climate model to downscale precipitation and temperature to the Mekong catchment. This was accomplished using the Global Circulation Model GFDL-CM to provide the boundary conditions under two carbon control strategies, namely representative concentration pathways (RCP) 4.5 and a RCP 8.5 scenario. The RCP 4.5 scenario represents the carbon strategy required to meet the Paris Accord, which aims to limit peak global temperatures to below a 2 °C rise whilst seeking to pursue options that limit temperature rise to 1.5 °C. The RCP 8.5 scenario is associated with a larger 3-4 °C rise. In addition, we also constructed a range of socio-economic scenarios to investigate the potential impacts of changing population, atmospheric pollution, economic growth and land use change up to the 2050s. Results of INCA simulations indicate increases in mean flows of up to 24%, with flood flows in the monsoon period increasing by up to 27%, but with increasing periods of drought up to 2050. A shift in the timing of the monsoon is also simulated, with a 4 week advance in the onset of monsoon flows on average. Decreases in nitrogen and phosphorus concentrations occur primarily due to flow dilution, but fluxes of these nutrients also increase by 5%, which reflects the changing flow, land use change and population changes.

4.
Br Dent J ; 226(1): 40-49, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30631165

RESUMO

Introduction: It is well established that dentistry is a stressful profession, primarily due to the nature and working conditions in the dental surgery. With dramatic changes taking place in the profession in recent years it is important to establish the impact this has on dentists' well-being. Aims: To determine the levels of stress and burnout in UK dentists and how this relates to well-being and identify the sources of work-related stress dentists report in different fields of practice. Materials and method: An online survey comprising of validated measures examining stress, burnout and well-being in dentists was administered to British Dental Association (BDA) members and non-members. Results: Valid responses were received from 2053 respondents. Dentists working in the UK exhibit high levels of stress and burnout and low well-being. General dental practitioners (GDPs) seem to be particularly affected. Issues relating to regulation and fear of litigation were deemed to be the most stressful aspects of being a dentist. Conclusions: The findings from this study build upon existing research showing that dentistry is a stressful profession. The sources of this stress appear to have shifted over the years, highlighting the changing landscape of dentistry. Interventions should focus on addressing these stressors by making changes to the working conditions of dentists.


Assuntos
Esgotamento Profissional , Esgotamento Psicológico , Odontólogos , Humanos , Inquéritos e Questionários , Reino Unido
5.
Sci Total Environ ; 697: 134090, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-32380601

RESUMO

Heavy metal pollution from tanneries is a global problem in many rapidly developing economies. Effluent discharges into rivers cause serious problems for water quality, damaging ecology and threatening the livelihoods of people, especially in developing urban centres which often have a high concentration of factories. The industry intensive capital area of Bangladesh is impacted with high levels of metals pollution in rivers in the Greater Dhaka Watershed. Sampling and modelling studies have been undertaken to assess pollution in the Buriganga River System in Dhaka. The process based, dynamic model INCA (Integrated Catchments) model has been used to simulate metals along the Buriganga River System in Central Dhaka. Observed and simulated metals concentrations are high, and the model shows that the proposed transfer of the tannery industry upstream helps to reduce the pollution significantly downstream. However, moving the industry upstream may be counterproductive as it is discharged into the upper reaches of the river. This will create pollution upstream unless the newly constructed effluent treatment system can operate at a high level.

6.
Sci Total Environ ; 652: 382-397, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30366338

RESUMO

Eutrophication and anoxia are unresolved issues in many large waterbodies. Globally, management success has been inconsistent, highlighting the need to identify approaches which reliably improve water quality. We used a process-based model chain to quantify effectiveness of terrestrial nutrient control measures on in-lake nitrogen, phosphorus, chlorophyll and dissolved oxygen (DO) concentrations in Lake Simcoe, Canada. Across a baseline period of 2010-2016 hydrochemical outputs from catchment models INCA-N and INCA-P were used to drive the lake model PROTECH, which simulated water quality in the three main basins of the lake. Five terrestrial nutrient control strategies were evaluated. Effectiveness differed between catchments, and water quality responses to nutrient load reductions varied between deep and shallow lake basins. Nutrient load reductions were a significant driver of increased DO concentrations, however strategies which reduced tributary inflow had a greater impact on lake restoration, associated with changes in water temperature and chemistry. Importantly, when multiple strategies were implemented simultaneously, resultant large flow reductions induced warming throughout the water column. Negative impacts of lake warming on DO overwhelmed the positive effects of nutrient reduction, and limited the effectiveness of lake restoration strategies. This study indicates that rates of lake recovery may be accelerated through a coordinated management approach, which considers strategy interactions, and the potential for temperature change-induced physical and biological feedbacks. Identified impacts of flow and temperature on rates of lake recovery have implications for management sustainability under a changing climate.

7.
Br Dent J ; 225(5): 425-430, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30215416

RESUMO

Introduction The share of the dental market held by corporate bodies continues to increase. With the profession currently facing many challenges it is important to understand their place in the profession and their effect.Aim This exploratory study aims to provide an insight into dental associates in relation to their working environment. Specifically, the differences between working in corporate and non-corporate environments in England.Materials and methods Secondary analysis of a self-report questionnaire examining demographics, pay, working conditions, job satisfaction and morale using a combination of closed and open-ended responses sent to randomly selected associate dentists who are BDA members. Responses from associates working in England solely in either the corporate or non-corporate sector were analysed.Results Significant differences were seen between associates working in corporate practice when compared to those in non-corporates practice, for example, significantly less corporate associates were female and corporate associates reported relatively lower levels of autonomy and control.Discussion The differences seen between sectors could be related to rationalisation and should this be the reality it could have far reaching effects on the profession and its ability to manage itself.Conclusion This study highlights some differences between the corporate and non-corporate dental sectors. Further work is needed to build a deeper understanding of the sector.


Assuntos
Odontologia , Odontólogos/psicologia , Prática Privada , Corporações Profissionais , Local de Trabalho , Adulto , Idoso , Tomada de Decisões , Recursos Humanos em Odontologia/psicologia , Inglaterra , Feminino , Humanos , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Moral , Motivação , Autonomia Pessoal , Administração da Prática Odontológica , Relações Profissional-Paciente , Autorrelato , Inquéritos e Questionários
8.
Artigo em Inglês | MEDLINE | ID: mdl-29177109

RESUMO

OBJECTIVE: Alzheimer's disease (AD) is a neurodegenerative disorder for which more than 20 genetic loci have been implicated to date. However, studies demonstrate not all genetic factors have been identified. Therefore, in this study we seek to identify additional rare variants and novel genes potentially contributing to AD. METHODS: Whole exome sequencing was performed on 23 multi-generational families with an average of eight affected subjects. Exome sequencing was filtered for rare, nonsynonymous and loss-of-function variants. Alterations predicted to have a functional consequence and located within either a previously reported AD gene, a linkage peak (LOD>2), or clustering in the same gene across multiple families, were prioritized. RESULTS: Rare variants were found in known AD risk genes including AKAP9, CD33, CR1, EPHA1, INPP5D, NME8, PSEN1, SORL1, TREM2 and UNC5C. Three families had five variants of interest in linkage regions with LOD>2. Genes with segregating alterations in these peaks include CD163L1 and CLECL1, two genes that have both been implicated in immunity, CTNNA1, which encodes a catenin in the cerebral cortex and MIEF1, a gene that may induce mitochondrial dysfunction and has the potential to damage neurons. Four genes were identified with alterations in more than one family include PLEKHG5, a gene that causes Charcot-Marie-Tooth disease and THBS2, which promotes synaptogenesis. CONCLUSION: Utilizing large families with a heavy burden of disease allowed for the identification of rare variants co-segregating with disease. Variants were identified in both known AD risk genes and in novel genes.

9.
Neurosci Lett ; 649: 124-129, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28400126

RESUMO

Several variants in the gene ABCA7 have been identified as potential causal variants for late-onset Alzheimer's disease (LOAD). In order to replicate these findings, and search for novel causal variants, we performed targeted sequencing of this gene in cohorts of non-Hispanic White (NHW) and African-American (AA) LOAD cases and controls. We sequenced the gene ABCA7 in 291 NHW LOAD cases and 103 controls. Variants were prioritized for rare, damaging variants and previously reported variants associated with LOAD, and were follow-up genotyped in 4076 NHW and 1157 AA cases and controls. We confirm three previously associated ABCA7 risk variants and extend two of these associations to other populations, an intronic variant in NHW (P=3.0×10-3) (originally reported in a Belgian population), and a splice variant originally associated in the Icelandic population, which was significantly associated in the NHW cohort (P=1.2×10-6) and nominally associated in the AA cohort (P=0.017). We also identify a 3'-UTR splice variant that segregates in four siblings of one family and is nominally associated with LOAD (P=0.040). Multiple variants in ABCA7 contribute to LOAD risk.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Doença de Alzheimer/genética , Predisposição Genética para Doença , Negro ou Afro-Americano/genética , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Íntrons , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , População Branca/genética
10.
Environ Sci Process Impacts ; 19(4): 586-595, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28322378

RESUMO

The application of metaldehyde to agricultural catchment areas to control slugs and snails has caused severe problems for drinking water supply in recent years. In the River Thames catchment, metaldehyde has been detected at levels well above the EU and UK drinking water standards of 0.1 µg l-1 at many sites across the catchment between 2008 and 2015. Metaldehyde is applied in autumn and winter, leading to its increased concentrations in surface waters. It is shown that a process-based hydro-biogeochemical transport model (INCA-contaminants) can be used to simulate metaldehyde transport in catchments from areas of application to the aquatic environment. Simulations indicate that high concentrations in the river system are a direct consequence of excessive application rates. A simple application control strategy for metaldehyde in the Thames catchment based on model results is presented.


Assuntos
Acetaldeído/análogos & derivados , Água Potável/análise , Água Doce/análise , Moluscocidas/análise , Rios/química , Poluentes Químicos da Água/análise , Acetaldeído/efeitos adversos , Acetaldeído/análise , Agricultura , Água Potável/química , Inglaterra , Água Doce/química , Moluscocidas/química , Abastecimento de Água
11.
Sci Total Environ ; 572: 1447-1448, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27817803
12.
Sci Total Environ ; 572: 1611-1621, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27302375

RESUMO

Good hygienic quality of surface waters is essential for drinking water production, irrigation of crops and recreation. Predictions of how and when microbes are transported by rivers are needed to protect downstream water users. In this study we tested the new process-based INCA-Pathogens model in the agricultural Loimijoki River basin (3138km2) in Finland, and we quantified ecosystem services of water purification and water provisioning for drinking and recreation purposes under different scenarios. INCA is a catchment scale process based model to calculate pollutant transfer from terrestrial environment and point sources to the catchment outlet. A clear gradient was observed in the numbers of faecal coliforms along the River Loimijoki. The highest bacterial counts were detected in the middle part of the main stream immediately after small industries and municipal sewage treatment plants. In terms of model performance, the INCA-Pathogen model was able to produce faecal coliform counts and seasonality both in the low pollution level sampling points and in the high pollution level sampling points. The model was sensitive to the parameters defining light decay in river water and in soil compartment, as well as to the amount of faecal coliforms in the manure spread on the fields. The modeling results showed that the number of faecal coliforms repeatedly exceeded 1000 bacteria 100ml-1. Moreover, results lead to the following conclusions: 1) Climate change does not cause a major threat to hygienic water quality as higher precipitation increases runoff and causes diluting effect in the river, 2) Intensification of agriculture is not a threat as long as animal density remains relatively low and environmental legislation is followed, 3) More intensive agriculture without environmental legislation causes a threat especially in tributaries with high field percentage and animal density, and 4) Hygienic water quality in the River Loimijoki can best be improved by improving sewage treatment. We conclude that this catchment scale model is a useful tool for addressing catchment management and water treatment planning issues.


Assuntos
Água Potável/microbiologia , Enterobacteriaceae/isolamento & purificação , Monitoramento Ambiental/métodos , Rios/microbiologia , Águas Residuárias/microbiologia , Agricultura , Finlândia , Modelos Teóricos , Purificação da Água , Abastecimento de Água
13.
Sci Total Environ ; 572: 1461-1470, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27090411

RESUMO

The fate of persistent organic pollutants (POPs) in riverine environments is strongly influenced by hydrology (including flooding) and fluxes of sediments and organic carbon. Coupling multimedia fate models (MMFMs) and hydrobiogeochemical transport models offers unique opportunities for understanding the environmental behaviour of POPs. While MMFMs are widely used for simulating the fate and transport of legacy and emerging pollutants, they use greatly simplified representations of climate, hydrology and biogeochemical processes. Using additional information about weather, river flows and water chemistry in hydrobiogeochemical transport models can lead to new insights about POP behaviour in rivers. As most riverine POPs are associated with suspended sediments (SS) or dissolved organic carbon (DOC), coupled models simulating SS and DOC can provide additional insights about POPs behaviour. Coupled simulations of river flow, DOC, SS and POP dynamics offer the possibility of improved predictions of contaminant fate and fluxes by leveraging the additional information in routine water quality time series. Here, we present an application of a daily time step dynamic coupled multimedia fate and hydrobiogeochemical transport model (The Integrated Catchment (INCA) Contaminants model) to simulate the behaviour of selected PCB congeners in the River Thames (UK). This is a follow-up to an earlier study where a Level III fugacity model was used to simulate PCB behaviour in the Thames. While coupled models are more complex to apply, we show that they can lead to much better representation of POPs dynamics. The present study shows the importance of accurate sediment and organic carbon simulations to successfully predict riverine PCB transport. Furthermore, it demonstrates the important impact of short-term weather variation on PCB movement through the environment. Specifically, it shows the consequences of the severe flooding, which occurred in early 2014 on sediment PCB concentrations in the River Thames.


Assuntos
Monitoramento Ambiental , Bifenilos Policlorados/análise , Rios/química , Poluentes Químicos da Água/análise , Inglaterra , Modelos Teóricos
14.
Sci Total Environ ; 572: 1601-1610, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26875602

RESUMO

Pathogens are an ongoing issue for catchment water management and quantifying their transport, loss and potential impacts at key locations, such as water abstractions for public supply and bathing sites, is an important aspect of catchment and coastal management. The Integrated Catchment Model (INCA) has been adapted to model the sources and sinks of pathogens and to capture the dominant dynamics and processes controlling pathogens in catchments. The model simulates the stores of pathogens in soils, sediments, rivers and groundwaters and can account for diffuse inputs of pathogens from agriculture, urban areas or atmospheric deposition. The model also allows for point source discharges from intensive livestock units or from sewage treatment works or any industrial input to river systems. Model equations are presented and the new pathogens model has been applied to the River Thames in order to assess total coliform (TC) responses under current and projected future land use. A Monte Carlo sensitivity analysis indicates that the input coliform estimates from agricultural sources and decay rates are the crucial parameters controlling pathogen behaviour. Whilst there are a number of uncertainties associated with the model that should be accounted for, INCA-Pathogens potentially provides a useful tool to inform policy decisions and manage pathogen loading in river systems.


Assuntos
Enterobacteriaceae/isolamento & purificação , Monitoramento Ambiental/métodos , Rios/microbiologia , Rios/parasitologia , Agricultura , Inglaterra , Modelos Teóricos , Rios/virologia , Sensibilidade e Especificidade , Águas Residuárias/microbiologia , Águas Residuárias/parasitologia , Águas Residuárias/virologia
15.
Environ Sci Process Impacts ; 17(6): 1070-81, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26030652

RESUMO

There are ongoing discussions about the appropriate level of complexity and sources of uncertainty in rainfall runoff models. Simulations for operational hydrology, flood forecasting or nutrient transport all warrant different levels of complexity in the modelling approach. More complex model structures are appropriate for simulations of land-cover dependent nutrient transport while more parsimonious model structures may be adequate for runoff simulation. The appropriate level of complexity is also dependent on data availability. Here, we use PERSiST; a simple, semi-distributed dynamic rainfall-runoff modelling toolkit to simulate flows in the Upper Ganges and Brahmaputra rivers. We present two sets of simulations driven by single time series of daily precipitation and temperature using simple (A) and complex (B) model structures based on uniform and hydrochemically relevant land covers respectively. Models were compared based on ensembles of Bayesian Information Criterion (BIC) statistics. Equifinality was observed for parameters but not for model structures. Model performance was better for the more complex (B) structural representations than for parsimonious model structures. The results show that structural uncertainty is more important than parameter uncertainty. The ensembles of BIC statistics suggested that neither structural representation was preferable in a statistical sense. Simulations presented here confirm that relatively simple models with limited data requirements can be used to credibly simulate flows and water balance components needed for nutrient flux modelling in large, data-poor basins.


Assuntos
Monitoramento Ambiental/métodos , Modelos Teóricos , Chuva , Abastecimento de Água/estatística & dados numéricos , Teorema de Bayes , Clima , Hidrologia , Rios/química , Temperatura , Movimentos da Água
16.
Environ Sci Process Impacts ; 17(6): 1098-110, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25892033

RESUMO

Anthropogenic climate change has impacted and will continue to impact the natural environment and people around the world. Increasing temperatures and altered rainfall patterns combined with socio-economic factors such as population changes, land use changes and water transfers will affect flows and nutrient fluxes in river systems. The Ganga river, one of the largest river systems in the world, supports approximately 10% global population and more than 700 cities. Changes in the Ganga river system are likely to have a significant impact on water availability, water quality, aquatic habitats and people. In order to investigate these potential changes on the flow and water quality of the Ganga river, a multi-branch version of INCA Phosphorus (INCA-P) model has been applied to the entire river system. The model is used to quantify the impacts from a changing climate, population growth, additional agricultural land, pollution control and water transfers for 2041-2060 and 2080-2099. The results provide valuable information about potential effects of different management strategies on catchment water quality.


Assuntos
Mudança Climática , Monitoramento Ambiental , Fósforo/análise , Poluentes Químicos da Água/análise , Agricultura , Cidades , Ecossistema , Índia , Rios , Fatores Socioeconômicos
17.
Environ Sci Process Impacts ; 17(6): 1057-69, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25736595

RESUMO

The potential impacts of climate change and socio-economic change on flow and water quality in rivers worldwide is a key area of interest. The Ganges-Brahmaputra-Meghna (GBM) is one of the largest river basins in the world serving a population of over 650 million, and is of vital concern to India and Bangladesh as it provides fresh water for people, agriculture, industry, conservation and for the delta system downstream. This paper seeks to assess future changes in flow and water quality utilising a modelling approach as a means of assessment in a very complex system. The INCA-N model has been applied to the Ganges, Brahmaputra and Meghna river systems to simulate flow and water quality along the rivers under a range of future climate conditions. Three model realisations of the Met Office Hadley Centre global and regional climate models were selected from 17 perturbed model runs to evaluate a range of potential futures in climate. In addition, the models have also been evaluated using socio-economic scenarios, comprising (1) a business as usual future, (2) a more sustainable future, and (3) a less sustainable future. Model results for the 2050s and the 2090s indicate a significant increase in monsoon flows under the future climates, with enhanced flood potential. Low flows are predicted to fall with extended drought periods, which could have impacts on water and sediment supply, irrigated agriculture and saline intrusion. In contrast, the socio-economic changes had relatively little impact on flows, except under the low flow regimes where increased irrigation could further reduce water availability. However, should large scale water transfers upstream of Bangladesh be constructed, these have the potential to reduce flows and divert water away from the delta region depending on the volume and timing of the transfers. This could have significant implications for the delta in terms of saline intrusion, water supply, agriculture and maintaining crucial ecosystems such as the mangrove forests, with serious implications for people's livelihoods in the area. The socio-economic scenarios have a significant impact on water quality, altering nutrient fluxes being transported into the delta region.


Assuntos
Mudança Climática , Secas , Inundações , Modelos Teóricos , Rios/química , Abastecimento de Água/estatística & dados numéricos , Agricultura , Conservação dos Recursos Naturais , Índia , Fatores Socioeconômicos
18.
Environ Sci Process Impacts ; 17(6): 1032-46, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25683650

RESUMO

Arsenic in drinking water is the single most important environmental issue facing Bangladesh; between 35 and 77 million of its 156 million inhabitants are considered to be at risk from drinking As-contaminated water. This dominates the list of stress factors affecting health, livelihoods and the ecosystem of the delta region. There is a vast literature on the subject so this review provides a filter of the more important information available on the topic. The arsenic problem arises from the move in the 1980s and 1990s by international agencies to construct tube wells as a source of water free of pathogens, groundwater usually considered a safe source. Since arsenic was not measured during routine chemical analysis and also is difficult to measure at low concentrations it was not until the late 1990s that the widespread natural anomaly of high arsenic was discovered and confirmed. The problem was exacerbated by the fact that the medical evidence of arsenicosis only appears slowly. The problem arises in delta regions because of the young age of the sediments deposited by the GBM river system. The sediments contain minerals such as biotite which undergo slow "diagenetic" reactions as the sediments become compacted, and which, under the reducing conditions of the groundwater, release in the form of toxic As(3+). The problem is restricted to sediments of Holocene age and groundwater of a certain depth (mainly 30-150 m), coinciding with the optimum well depth. The problem is most serious in a belt across southern Bangladesh, but within 50 m of the coast the problem is only minor because of use of deep groundwater; salinity in shallow groundwater here is the main issue for drinking water. The Government of Bangladesh adopted a National Arsenic Policy and Mitigation Action Plan in 2004 for providing arsenic safe water to all the exposed population, to provide medical care for those who have visible symptoms of arsenicosis. There is as yet no national monitoring program in place. Various mitigation strategies have been tested, but generally the numerous small scale technological remedies have proved unworkable at village level. The current statistics show that use of deep groundwater (below 150 m) is the main source of arsenic mitigation over most of the arsenic affected areas as well as rainwater harvesting in certain location.


Assuntos
Arsênio/análise , Monitoramento Ambiental , Água Subterrânea/química , Poluentes Químicos da Água/análise , Bangladesh
19.
Environ Sci Process Impacts ; 17(6): 1082-97, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25692851

RESUMO

This study investigates the potential impacts of future climate and socio-economic change on the flow and nitrogen fluxes of the Ganga river system. This is the first basin scale water quality study for the Ganga considering climate change at 25 km resolution together with socio-economic scenarios. The revised dynamic, process-based INCA model was used to simulate hydrology and water quality within the complex multi-branched river basins. All climate realizations utilized in the study predict increases in temperature and rainfall by the 2050s with significant increase by the 2090s. These changes generate associated increases in monsoon flows and increased availability of water for groundwater recharge and irrigation, but also more frequent flooding. Decreased concentrations of nitrate and ammonia are expected due to increased dilution. Different future socio-economic scenarios were found to have a significant impact on water quality at the downstream end of the Ganga. A less sustainable future resulted in a deterioration of water quality due to the pressures from higher population growth, land use change, increased sewage treatment discharges, enhanced atmospheric nitrogen deposition, and water abstraction. However, water quality was found to improve under a more sustainable strategy as envisaged in the Ganga clean-up plan.


Assuntos
Mudança Climática , Modelos Químicos , Nitrogênio/análise , Poluentes da Água/análise , Bangladesh , Monitoramento Ambiental , Índia , Rios/química , Fatores Socioeconômicos
20.
Sci Total Environ ; 481: 157-66, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24594744

RESUMO

The issues of diffuse and point source phosphorus (P) pollution in the Hampshire Avon and Blashford Lakes are explored using a catchment model of the river system. A multibranch, process based, dynamic water quality model (INCA-P) has been applied to the whole river system to simulate water fluxes, total phosphorus (TP) and soluble reactive phosphorus (SRP) concentrations and ecology. The model has been used to assess impacts of both agricultural runoff and point sources from waste water treatment plants (WWTPs) on water quality. The results show that agriculture contributes approximately 40% of the phosphorus load and point sources the other 60% of the load in this catchment. A set of scenarios have been investigated to assess the impacts of alternative phosphorus reduction strategies and it is shown that a combined strategy of agricultural phosphorus reduction through either fertiliser reductions or better phosphorus management together with improved treatment at WWTPs would reduce the SRP concentrations in the river to acceptable levels to meet the EU Water Framework Directive (WFD) requirements. A seasonal strategy for WWTP phosphorus reductions would achieve significant benefits at reduced cost.


Assuntos
Hidrologia , Lagos/química , Modelos Químicos , Fósforo/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/legislação & jurisprudência , Conservação dos Recursos Naturais , Inglaterra , Monitoramento Ambiental , Política Ambiental , Movimentos da Água , Poluição Química da Água/prevenção & controle , Poluição Química da Água/estatística & dados numéricos
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