地下水砷（As）異常是飲用水的主要威脅之一,由于廣泛分布,已成為全球關(guān)注的熱點(diǎn)問(wèn)題。地下水砷異常在孟加拉國(guó)已成為嚴(yán)重的環(huán)境地質(zhì)和危害公共健康問(wèn)題之一。據(jù)報(bào)道,孟加拉國(guó)飲水型地下水砷中毒常是世界范圍內(nèi)人口密度最高的砷中毒事件。在孟加拉國(guó),高砷地下水（>10μg/L）常發(fā)生在全新世沖積含水層。論文的主要研究目的是通過(guò)對(duì)孟加拉西南部全新世沖積含水層地下水的水化學(xué)特征和水文地球化學(xué)演化過(guò)程及其對(duì)As遷移富集過(guò)程的主控因素分析,揭示區(qū)域高砷地下水的形成機(jī)理,并與中國(guó)北方大同盆地的高砷地下水水化學(xué)特征及形成機(jī)理進(jìn)行了對(duì)比分析,指出其異同點(diǎn)。本次研究,共在孟加拉西南部采集78個(gè)井深范圍為21¹13m的地下水樣品（2015年50個(gè),2017年28個(gè)）,進(jìn)行主要離子、微量元素分析及氫氧同位素分析。在此基礎(chǔ)上,借助多元統(tǒng)計(jì)分析,如層次聚類(lèi)分析（HCA）和因子分析（FA）,識(shí)別沉積含水層中地下水形成的主要水文地球化學(xué)過(guò)程及影響砷遷移富集的主要控制因素。研究結(jié)果表明,孟加拉西南部2015年采集的50個(gè)地下水樣品As濃度范圍為6.05⁵90.7μg/L,平均值為... 

【文章來(lái)源】：中國(guó)地質(zhì)大學(xué)湖北省 211工程院校 教育部直屬院校

【文章頁(yè)數(shù)】：215 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
Selected Publications
Curriculum Vitae of Md. Enamul Huq
摘要
abstract
Chapter 1 Introduction
    1.1 Background
    1.2 Statement of the problems
    1.3 Significance and objectives of the study
    1.4 Rational, context and scope of the study
    1.5 Scientific contribution
    1.6 Thesis structure
Chapter 2 Theoretical Background and Literature Review
    2.1 Introduction
    2.2 Evolution and occurrence of As in groundwater
    2.3 Chemical form of As
    2.4 Groundwater As and threat to the public health
    2.5 Sources of As
        2.5.1 Primary sources
        2.5.2 Secondary sources
        2.5.3 Tertiary/irrigational re-circulation
    2.6 As mobilization
        2.6.1 Reduction of metal oxides and hydroxides
        2.6.2 Reduction of As（V） to As（III）
        2.6.3 Biogeochemical processes and organic matter
        2.6.4 Pyrite oxidation hypothesis
        2.6.5 Competitive ion exchange mechanism
    2.7 Literature review and research gap
Chapter 3 Research Methodology
    3.1 Study area
        3.1.1 Location
        3.1.2 Climate
        3.1.3 Hydrogeological setting
        3.1.4 Geology and lithology
    3.2 Groundwater sampling
    3.3 Groundwater analysis
    3.4 Statistical and spatial analysis
Chapter 4 Distribution and hydrochemical characteristics of high As groundwater
    4.1 Introduction
    4.2 Spatial distribution of high As groundwater
    4.3 Hydrochemical characteristics
        4.3.1 Contents of major ions and physical parameters
        4.3.2 Hydrochemical type
        4.3.3 Comparison of hydrochemical data collected in two different years
        4.3.4 Trace metals （TMs）
        4.3.5 Variation of TMs concentration over time
    4.4 Stable isotope geochemistry
        4.4.1 Recharge sources of groundwater
Chapter 5 As enrichment and mobilization in groundwater of Southwestern Bangladesh
    5.1 As sources
    5.2 Influential factors of As enrichment
        5.2.1 Geographical location and climatic condition
        5.2.2 Runoff conditions
        5.2.3 p H values
        5.2.4 Redox environment
        5.2.5 TDS
    5.3 The processes responsible for As enrichment and mobilization
        5.3.1 Redox
        5.3.2 Role of p H
        5.3.3 Evaporation
        5.3.4 Role of ions and TMs to mobilize As
        5.3.5 Adsorption-desorption and ion exchange process
        5.3.6 Microbial processes of As mobilization
        5.3.7 Other factors
    5.4 Co-occurrence of As and salinity
    5.5 Groundwater quality with respect WHO, USEPA and Bangladesh standards
Chapter 6 Comparison of hydrogeochemical behavior in Datong Basin, China and Southwestern, Bangladesh
    6.1 Introduction
    6.2 Brief introduction of Datong Basin
    6.3 Hydrogeochemistry
        6.3.1 Datong Basin, China
        6.3.2 Southwestern, Bangladesh
        6.3.3 Differences between Datong Basin, China and Southwestern Bangladesh
    6.4 Arsenic occurrence in groundwater
        6.4.1 Datong Basin, China
        6.4.2 Southwestern Bangladesh
        6.4.3 Differences between Datong Basin, China and Southwestern Bangladesh
    6.5 As release and enrichment
        6.5.1 Datong Basin, China
        6.5.2 Southwestern Bangladesh
        6.5.3 Differences between Datong Basin, China and Southwestern Bangladesh
Chapter 7 Conclusion and Recommendation
    7.1 Conclusions
    7.2 Recommendations
    7.3 Limitations and future work
References
Acknowledgements



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