【作者】 严明疆；

【导师】 张光辉； 张兆吉；

【作者基本信息】 中国地质科学院 ， 地质工程， 2006， 博士

【摘要】 地下水系统脆弱性评价是制定地下水利用和保护综合措施的重要依据。本文从加深认识地下水系统脆弱性本质属性的要求、认识人类活动与地下水相互作用关系的要求、合理利用和保护地下水资源的要求和实现经济可持续发展的要求四个方面阐述了地下水系统脆弱性对人类活动响应研究的意义，由此确定本文的研究目的，即通过研究近50年来地下水系统脆弱性对人类活动的响应机制，揭示人类活动对地下水的影响机理，为实现地下水资源可持续开发与保护提供理论依据。根据近50年来华北地区滹滏平原地下水开采强度、地下水位下降速率以及水质变化特征，分为三个时期，从地下水动力场和和地下水化学场演变特征分析入手，阐明了人类活动对地下水系统脆弱性的影响状况，包括：①长期过量开采引起地下水位的持续下降，改变了地下水的天然补给、径流和排泄条件。②大范围地下水位降落漏斗形成和变化过程。③人类开采对地下水化学场的天然平衡的影响。本文侧重地下水防污性和地下水资源脆弱性评价。选择地下水位埋深、包气带岩性、含水层砂层厚度、含水层水力传导系数和降雨补给量作为地下水防污性评价指标，以补给量、给水度、地下水质量、富水性、地下水可开采量、地下水储存量和开采强度作为地下水资源脆弱性评价指标。采用灰色关联度法和BP神经网络法两种方法分别计算了地下水防污性和地下水资源脆弱性评价指标权重。然后应用DRITC方法和综合指数法分别计算了地下水防污性和地下水资源脆弱性综合指数，形成地下水防污性图和地下水资源脆弱性图。在此基础上，从空间和时间上结合分析了地下水防污性和地下水资源脆弱性区位特征及变化趋势。滹滏平原中部地下水防污性好于西部，西部地下水防污性好于东部，地下水资源脆弱性由北向南升高，淡水区地下水资源脆弱性低于咸水区。研究结果表明，①滹滏平原当地下水位降幅为0～7m时，地下水防污性变化不明显，当为7～25m时，地下水防污性增强一级概率较大，当地下水位降幅大于25m时，地下水防污性增大二级概率较大。②在滹滏平原淡水区，当地下水位降幅为0～12m时，地下水资源脆弱性一般变化不显著，当12～24m时，升高一级概率较大，当地下水位降幅大于24m时，地下水资源脆弱性升高二级可能性较大；咸水地区，当地下水位降幅在4～10m时，地下水资源脆弱性一般不发生变化，为14～18m时，升高一级概率较大，当地下水位降幅大于22m时，地下水资源脆弱性升高二级概率较大。③地下水位埋深增大是地下水防污性增强的主要因素。人类活动(抽取地下水)改变地下水位埋深，间接改变包气带厚度和降雨入渗补给系数，使污染物进入地下水时间、数量和与周围环境发生物理化学反应的机会改变，致使地下水防污性能发生变化。地下水资源脆弱性则主要取决于地下水系统内部条件，人类活动(抽取地下水)只是使地下水资源脆弱性变化的诱导因素，只有人类活动对地下水环境产生强烈影响时，才转变为影响地下水资源脆弱性的主要因素。根据地下水防污性和地下水资源脆弱性研究结果，将滹滏平原地下水系统脆弱性划分为4个一级区和13个二级区。确定滹滏平原淡水区最佳地下水位埋深为27～30m和咸水区最佳地下水位埋深为15～19m。根据上述综合评价结果，将滹滏平原地下水合理开采利用和保护划分为4个区和11个子区。本文特色及创新点是以数学方法计算评价指标权重克服了DRASTIC方法重唯一性。并且首次从地下水质与量两方面对滹滏平原地下水系统脆弱性进行了综合评价和趋势分析，阐明了地下水系统脆弱性对人类活动的响应机制。最后应用研究综合结果提出了滹滏平原地下水合理利用与保护对策。更多还原

【Abstract】 It is important base to environmental protection and groundwater feasibleexploitation and protection that groundwater system vulnearability assessment. Thispaper discussed the important significance that the research on groundwater systemvulnerability responding to human activities based on four aspects:the necessary demandto comprehended more inherent attribute of groundwater system vulnerability, the inevitableresult to research the affect between groundwater and human activities each other, therequirement of groundwater resources proper utilization and protection,the final need tokeep economic sustainable development. Finally, determining the research purporses ofthe paper are to research how groundwater system vulnerability responded to humanactivities and how anthropic activity impacted on groundwater system vulnerability, andguides to groundwater resource sustainable development.The paper clarified that human activities impacted on groundwater based on the change ofgroundwater dynamical field and chemic field and dividing into three stage based on groundwaterexploitation density, water table change and groundwater quality deteriorate recent fifty years. Theresults are①that the groundwater recharge,runoff and drainage have been changedbecause of overexploitation long-term and making water table change.②that there hasbeen groundwater pumping cone③The TDS and chemic ingredient have been changedbecause human activities disturbed groundwater natural chemic field.The paper foused on the assessment of groundwater aquifer snesitivity andgroundwater resources vulnerability.The former assessment factors are groundwaterdepth, thickness of aquifer send body, hydraulic conductity of the aquifer, vadose zonelithology and recharge of precipitation.The latter assessment factors are groundwaterrecharge, groundwater specific yield, groundwater exploitation intensity, groundwaterTDS, aquifef effective porosity, groundwater feasible exploitation and aquiferthickness.The paper computed the weight of aquifer snesitivity and groundwaterresources vulnerability by grey theory and BP network and proved their reasonable eachother,and assessed aquifer snesitivity and groundwater resources vulnerability andformed their map respectively, the aquifer snesitivity in middle of the Hufu plain isbatter than west and west is better than east; fresh water area is better than salty waterarea.Based on above studies,①the groundwater aquifer snesitivity is invisible whenwater table falling extent is less than 7m; it is probable that groundwater aquifer snesitivity enhanced one level when water table falling extent is 7～25m and aquifersnesitivity enhanced two level when water table falling extent is more than 25m.②Infresh groundwater area, the groundwater resourcrs vulnerability change is unobviouswhen water table falling extent is less than 12m; it is probable that groundwaterresources vulnerability strongthed one level when water table falling extent is 12～24mand groundwater resources vulnerability enhanced two level when water table fallingextent is more than 24m. In salty groundwater area, the groundwater resourcrsvulnerability change is unobvious when water table falling extent is 4～10m; it isprobable that groundwater resources vulnerability strongthed one level when water tablefalling extent is 14～18m and groundwater resources vulnerability enhanced two levelwhen water table falling extent is more than 22m.③The water table deepened is firstfactor to enhanced groundwater aquifer snesitivity,which reduced the chance ofcontamination penetrated into aquifer because groundwater exploitation thickenedvadose zone and reduced precipitation recharge coefficient.The groundwater resourcesvulnerability depend on groundwater system natural conditions and human activities aredominant factor when it impacted intensively on groundwater.The paper analysed comprehensively groundwater system vulnerability and divideHufu plain into 4 area and subdivided into 13 subarea Based on the law of change ofgroundwater aquifer snesitivity and groundwater resources vulnerability with watertable falling extent, optimal water table is 27～30m in fresh groundwater area and 15～19m in salty groundwater area.Finally, the paper divided groundwater exploitation into 4area and subdivided into 11 subarea in Hufu plain based on actuality and current ofgroundwater system vulnerability, groundwateroptimal water table and actuality ofgroundwater depth.The paper overcomed the short of DRASTIC method by mathematics simulationthe assessment factors, assessed comprehensively assessed groundwater systemvulnerability and put forward measures of groundwater proper utilization andprotection,which were innovation of groundwater system vulnerability and offeringreference of groundwater exploitation and protection.更多还原