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1.
石家庄市地下水中氮污染分析   总被引:25,自引:1,他引:25  
通过对石家庄市地下水中“三氮”污染状况的分析,发现硝酸盐是地下水中的主要氮污染物,利用氮同位素方法分析了地下水中硝酸盐氮的来源,讨论了人类开采地下水和施放环境物质对地下水中氮聚集的影响,在人类活动影响强度小的地区,地下水中的硝酸盐污染强度大大低于市区。NO3-浓度与硬度变化趋势表明:氮污染与硬度等指标值升高有一定的联系,但在不同的水文地球化学环境中,在迁移和转化等方面又有着自己的特性。  相似文献   

2.
Groundwater quality is of vital importance in groundwater safety especially for the purpose of water supply, its management becomes more and more necessary as groundwater contamination has threaten its safe use in China. The article analyzed the contamination sources of groundwater and impact of contamination on human health and water supply, the knowledge gaps were pointed and recommendations were made for groundwater quality management in China.  相似文献   

3.
Many cities in developing countries are dependent upon groundwater for water supply. Frequently this groundwater is pumped from semi-confined aquifers in alluvial deposits. These deeper aquifers are often considered to be protected from polluted shallow water by intervening less-permeable layers. However, where groundwater is pumped from a semi-confined aquifer immediately beneath a city, significant induced leakage of contaminated shallow water can occur. This may lead to a serious deterioration of water quality in deeper aquifers in the longer-term. A simple model has been developed which provides insight into the hydraulic controls on water quality in such semi-confined aquifers. The model provides a tool for the initial assessment and prediction of the impact of urbanization on groundwater quality. Also, the model characterizes the key hydrogeological behaviour through a single parameter, here termed the ‘city leakage factor’, which can be used to assess the vulnerability to contamination by leakage. A case study of a city in Thailand illustrates the use of this model.
Résumé Beaucoup de villes des pays en développement dépendent de l’eau souterraine pour leur alimentation en eau. Cette eau souterraine est souvent pompée dans des aquifères alluviaux semi-captifs. Ces aquifères plus profonds sont souvent considérés comme protégés des eaux peu profondes et polluées, grace à des couches intercalaires moins perméables. Cependant, dans le cas où l’eau souterraine est pompée à partir d’un aquifère semi-captif situé directement sous une ville, une drainance importante des eaux peu profondes et polluées peut être induite. Ceci peut entra?ner, à long terme, une détérioration significative de la qualité de l’eau dans les aquifères plus profonds. Un modèle simple a été construit fournissant un aper?u des contr?les hydrauliques agissant sur la qualité de l’eau dans des aquifères semi-captifs. Ce modèle est un outil permettant d’évaluer l’état initial et de prédire l’impact de l’urbanisation sur la qualité de l’eau souterraine. Le modèle caractérise également les comportements hydrogéologiques majeurs à travers un unique paramètre, nommé dans cette étude facteur de drainance de la ville“, et qui peut être utilisé pour évaluer la vulnérabilité de l’aquifère face à une contamination par drainance. L’étude de cas d’une ville en Tha?lande illustre l’utilisation de ce modèle.

Resumen Muchas ciudades de paises en desarrollo dependen del agua subterránea para el abastecimiento de agua. Frecuentemente el agua subterránea se bombea de acuíferos semi-confinados en depósitos aluviales. Estos acuíferos más profundos se protegen frecuentemente de agua somera contaminada mediante la intervencción de capas menos permeables. Sin embargo, donde el agua subterránea se bombea de un acuífero semi-confinado inmediatamente debajo de una ciudad, pueden ocurrir fugas significativas inducidas de agua somera contaminada. Esto puede conducir a un serio deterioro de calidad de agua en acuíferos más profundos en el largo plazo. Se ha desarrollado un modelo simple el cual aporta idea acerca de los controles hidráulicos en la calidad del agua en tales acuíferos semi-confinados. El modelo aporta una herramienta para la evaluación inicial y predicción del impacto de urbanización en la calidad del agua subterránea. El modelo también caracteriza el comportamiento hidrogeológico clave a traves de un solo parámetro, que aquí se denomina ′factor de fuga de la ciudad′el cual puede usarse para evaluar la vulnerabilidad a la contaminación por fuga. El uso de este modelo se ilustra con un estudio de caso de una ciudad en Tailandia.

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4.
The city of Scarborough lies on the eastern margin of the Greater Toronto Area of southern Ontario, Canada, along the northern coastline of Lake Ontario. The City has a population of 500,000 and is presently one of the fastest growing communities in Canada. The City is expanding northwards onto rural land on the south slope of the large Pleistocene glacial Oak Ridges Moraine system. The moraine system is underlain by a thick (150 m) succession of tills, sands and gravels and is a regionally-significant recharge area for three principle aquifer systems that discharge to numerous watercourses that flow to Lake Ontario. Protection of deeper aquifers from surface-generated urban contaminants is a particular concern. A groundwater flow model using Visual MODFLOW was developed for the 350-km2 Rouge River–Highland Creek (RRHC) drainage basin using an extensive GIS-based collection of subsurface geological, geophysical and hydrogeological data, maps of land use and surficial geology. The RRHC model was calibrated against point water level data, known potentiometric surfaces of the principal aquifers and baseflow measurements from streamflow gauging stations and determined to be within acceptable limits. Water balance calculations indicate that 70% of the basin recharge (106,000 m3/day) enters the Upper Aquifer along the crest and immediate flanks of the Oak Ridges Moraine. To the south, Upper Aquifer water moving through fractured till aquitards accounts for more than 75% of recharge to deeper aquifers. Water quality data confirm previous observations that urban- and rural-sourced contaminants (chlorides and nitrates) present in Upper Aquifer waters are moving rapidly into deeper aquifers. Some 83% of total RRHC recharge water is ultimately discharged as baseflow to creeks draining to Lake Ontario; the remainder discharges to springs and along eroding lakeshore bluffs. Model results demonstrate that deeper aquifers are poorly protected from urban contaminants and that long-term protection of ground and surface water quality has to be a priority of municipal planners if the resource is not to be severely degraded. Electronic Publication  相似文献   

5.
西北地区地下水质量评价   总被引:10,自引:0,他引:10  
本文以地下水调查的水质分析资料和动态监测资料为基础,参照我国地下水质量标准和生活饮用水卫生标准,对西北地区地下水质量状况进行综合评价.结果表明西北地区地下水质量状况为全国较差的地区,不可直接利用的地下水多分布于该区内陆盆地中心地带;地下水污染多发生在主要城市、工矿企业及其周边地区,水污染主要呈点状、线状分布,主要超标项目为溶解性总固体、总硬度、硝酸盐、亚硝酸盐、硫酸盐、氯化物和氟化物等.  相似文献   

6.
The occurrence of human health problems resulting from arsenic contamination of domestic water supplies in Ron Phibun District, Nakhon Si Thammarat Province, southern Thailand was first recognized in 1987. The area has an extensive history of bedrock and alluvial mining, the waste from which is typically rich in arsenopyrite and related alteration products. In 1994 a collaborative study was instigated involving Thai and British government authorities to establish the distribution and geochemical form of As in surface drainage and aquifer systems in the affected area, the probable sources of As contamination, and the potential for problem alleviation. Hydrochemical analyses of surface- and groundwaters have confirmed the presence of dissolved As at concentrations exceeding WHO potable water guidelines by up to a factor of 500. Contamination of the shallow alluvial aquifer system is systematically more severe than the underlying carbonate-hosted aquifer. Deep boreholes may therefore provide the best available potable water source for the local population. The presence of up to 39% of total As as arsenite (H3AsO3) within the carbonate aquifer may, however, constitute a hidden toxicological risk, not evident in the shallow groundwater (in which arsenate species account for > 95% of total As). Mineralogical investigations of As-rich tailings and flotation wastes were undertaken to evaluate their likely impact on water quality. The results indicate that although some flotation wastes contain up to 30% As, the rate of leaching is extremely low. Consequently the As loading of drainage emanating from such waste is below the subregional average. Analyses of the silty alluvium that covers much of the central sector of the study area have highlighted As concentrations of up to 5000 mg kg–1, probably carried by disseminated arsenopyrite. Following sulfide dissolution, the mobility of As in this material may be high (with resultant contamination of shallow groundwater) due to the low Fe content of the soil. On the basis of the data acquired, a range of pollution mitigation schemes are currently under investigation including Fe supplementation of alluvium and microbial degradation of disseminated arsenopyrite.  相似文献   

7.
8.
近50 a,西北干旱内陆河流域经历了历史时期的水土资源过度开发和近期的生态保护修复的不同阶段,对区域地下水和生态环境产生了重要影响,但地下水长期演化规律及其生态效应认识尚不清晰。以新疆孔雀河流域为典型研究区,基于最新地下水监测数据与历史数据对比,分析流域地下水流场时空演化规律以及流域地下水对河岸带胡杨林的影响作用,探讨地下水长期演化的生态效应。结果表明:1971—2021年,孔雀河流域因过量集中开采地下水引起区域地下水流动系统发生根本性变化,地下水水位整体呈下降趋势,流域内累计降幅大于40 m的面积达204.69 km2,累计降幅20~40 m的面积为1735.81 km2,累计降幅5~20 m的面积为1018.56 km2,并形成地下水降落漏斗;生态输水前,中下游河道长时间断流,河岸带地下水水位埋深累计降幅超过10 m,导致河岸带胡杨林退化萎缩,2016年实施生态输水工程以后,埋深逐渐上升2~4 m,上升至胡杨林生长临界水位以上,2014—2018年天然胡杨林植被覆盖率增大17%。本研究有助于认识西北干旱内陆河流域地下水和生态环境演化规律,为类似区域地下水可持续开发利用与生态保护提供科学参考。  相似文献   

9.
太原市属于我国北方的半干旱地区,地下水资源是区内最重要的供水水源。然而,该地区代表性地下水的水质演化趋势与常规污染物分布特征表明,区内地下水已经遭受污染,在研究区南部,地下水污染问题尤为突出。分析了研究区地下水污染的原因,结果表明人类活动是最主要的因素,包括地下水开采、工业与生活废弃物的排放、农业污灌、化肥及农药的施用、采矿活动等。  相似文献   

10.
基于ArcView的濮阳市地下水环境质量评价系统及其应用   总被引:3,自引:0,他引:3  
基于ArcView,结合VC++和Crystal Reports(水晶报表)设计器,通过Avenue二次开发,并集成相应水质评价模型,开发了"濮阳市地下水环境质量评价子系统",该子系统能够对水化学信息进行查询检索、统计分析、制表等,并能进行地下水质综合评价,可方便管理者及时掌握地下水污染的空间分布及演化趋势.  相似文献   

11.
遵义市地下水污染趋势分析及防治对策   总被引:1,自引:0,他引:1  
杨秀忠 《贵州地质》2004,21(4):258-261
近年来遵义市两城区地下水污染日益加重,对地下水水质污染分布及变化规律进行分析研究,掌握地下水水质污染变化趋势,是当前区内地下水水质污染防治研究的首要任务。文中根据地下水综合水质评价指数F和累计超起始值污染指数Pi的计算结果,对地下水超起始值污染指数进行趋势面分析,并对水质污染态势进行类型分区,然后提出地下水污染防治对策。  相似文献   

12.
岩溶城镇区人类活动对地下水水质的影响   总被引:1,自引:0,他引:1  
以重庆市南山老龙洞地下河流域为研究单元,通过主成分分析和实地调查,研究该区域人类活动对岩溶地下水水质的影响,并探讨污染物的来源。结果表明,受城镇区人类活动影响,老龙洞地下河流域地下水 NO3--N和PO43--P污然最为严重,按 GB5749-2006规定,研究区的地下水已不可作为饮用水源。老龙洞地下河水NO3--N含量逐年在减少,而PO43--P却在增加,赵家院子泉水PO43--P增长也十分迅速,老龙洞地下河流域地下水受城镇化影响越来越明显。老龙洞地下河水受城镇人类活动、工业活动、农业活动的共同影响,污染比泉水严重。老龙洞地下河中NO3-和SO42-含量的减少,说明采取一些积极的措施,地下水的污染是可以得到治理的。  相似文献   

13.
为了研究陕西省泾惠渠灌区地下水污染特征及人体健康风险状况,采集地下水样品进行分析测定,首先运用单因子指数法进行污染评价,再利用GIS获取主要污染物As、Cr (Ⅵ)和NO3--N的空间分布特征,最后借鉴美国环境保护署的人体健康风险评价模型对灌区地下水污染物的人体健康风险做出评价。结果表明:研究区地下水中As、Cr (Ⅵ)、NO3--N的质量浓度均超标,As对成人的致癌风险最高达3.50×10-4,明显超出限值1.00×10-4,长期暴露对当地居民带来罹患癌症的健康风险较高;As、Cr (Ⅵ)、NO3--N的非致癌风险从大到小排序为Cr (Ⅵ)、NO3--N、As,其中Cr (Ⅵ)对儿童的非致癌风险最高,达8.693 7,远超限值1.000 0,危害性最大。空间分布特征方面,As的致癌风险区域面积比例最高,为42.82%,As、Cr (Ⅵ)、NO3--N的非致癌风险区域面积比例分别高达69.19%、69.06%和66.55%,水安全问题突出。  相似文献   

14.
武汉市区第四系含水层地下水有机污染敏感性研究   总被引:14,自引:0,他引:14  
在详细调查武汉市水文地质条件和地下水污染现状的基础上,获得了高精度的武汉市水环境中微量有机污染物的组成数据。所检测出的有机组分达30余种,以苯及相关苯系物为主,污染程度较高的地下水主要分布在人口密集区和工业,商业区,应用改进的DRASTIC模型-地下水污染敏感性评价模型,在GIS平台上,编制了武汉市区地下水污染敏感性分区图。根据其评价结果,建议集中对那些敏感性相对较高的区域采取有效的环保措施,开发利用时应作出风险评价。  相似文献   

15.
结合贵州省毕节地区水文地质调查资料和486口钻井资料发现:构造、岩性和地貌是控制钻孔是否成井的主要因素,应结合具体实例综合分析。寒武系娄山关组(2-3ls)、二叠系茅口组(P2q-m)、三叠系嘉陵江组(T1j)和关岭组(T2g)为主要岩溶找水层位,占成井总数的79.83%,成井率分别为88.1%、41.56%、76.32%、70.94%,平均单井涌水量分别为409.62 m~3/d、165.93 m~3/d、291.2 m~3/d、277.42 m~3/d,相较于厚层纯灰岩,灰岩夹碎屑岩地层和白云岩地层成井率更高,且钻孔平均涌水量更大;区域性断层不再是钻井找水的有利部位,中小型断裂等小构造控制局部富水区成为钻井找水的有利靶区,归纳4种钻探成井模式:中小型断裂控水模式、逆断层上盘富水模式、含水层与隔水层接触带富水模式、白云岩岩溶裂隙富水模式。  相似文献   

16.
北京小汤山地区第四系深层地下水氟含量普遍超标, 严重制约区域供水。在收集整理基础地质、水文地质、地热地质资料基础上, 开展第四系高氟地下水与地热水之间关系研究工作。研究表明: 小汤山地区位于复式背斜的核部区域, 该区热储层与第四系地层直接接触并形成水力“天窗”, 受构造应力影响在热储层发育大量张性裂隙, 加之上覆第四系盖层结构松散且厚度较薄, 导致该区成为地热富集带; 在高温高压环境下, 地热水中氟化物含量普遍较高, 地热水上涌同第四系深层地下水发生热流-冷流的混合作用, 导致第四系深层地下水中氟化物含量升高, 形成第四系高氟地下水。  相似文献   

17.
某城市工业区浅层地下水CAHs污染特征   总被引:3,自引:0,他引:3  
李海明  陈鸿汉  郑西来 《地学前缘》2005,12(Z1):132-138
2000—2002年采用气相色谱法对某市工业区浅层地下水中氯代脂肪烃(CAHs)含量进行了分析,在综合分析CAH污染的原因和途径的基础上,着重探讨了CAH在地下水系统中的迁移转化规律。结果表明,地下水中CAH检出率48 15%~85 19%,检出值质量浓度为0 1~71 89μg/L,与美国“EPA”标准5μg/L 相比,三氯乙烯、四氯乙烯超标率分别为59 26%和25 93%,超标倍数分别可达14 38 和9 128;三氯乙烯(TCE)和四氯乙烯(PCE)是主要污染物,重现性好;CAH对地下水的污染与其本身的物理性质、包气带的结构和地下水动力条件等因素有关,防污性能差的工业区CAH容易污染地下水;CAH在砂土中的迟后因子R值很小,很容易在地下环境中迁移;地下水流场是决定CAH分布的一个重要因素,沿着地下水流向,CAH浓度呈逐渐降低的趋势;地下水动态变化是引起CAH呈现季节性变化的主要原因。  相似文献   

18.
The paper focuses on the concentration of nitrates detected in superficial waters (lake and streams) and groundwater (wells) used as sources of water supply. It attempts to determine the level of risk due to the presence of urban industrial uses and correlate it with the quality of urban life, in order to determine social vulnerability to the risk of industrial contamination. A geographic information system (GIS) was constructed with layers for various census data, topographic and landuse features and the location of water samples. An index of quality of life was developed using selected variables. This was then compared to the essential services provision data and the results of the water sample analyses. The concentration of nitrates (mg/l or ppm) in the water samples was determined. These values were translated into maps of contaminants, which were then correlated with their possible sources and with the quality of life of the population affected. The concentration of nitrates in wells has been considered alarming, but more concern has been expressed about concentrations in the public water supply network. Spatial correlation between areas with high risk of contaminated water and areas with the worst quality of life, indicates the importance of controlling chemical contamination, and demands improvements in the public water supply network and revision of the theory of social vulnerability.  相似文献   

19.
The Shira region of Khakassia in southern Siberia exhibits many features governing the evolution of groundwater and surface-water chemistry that are common to other cold, semi-arid areas of the world: (1) a continental climate, (2) location in a rain shadow, (3) low density of surface-water drainage, (4) occurrence of saline lakes, and (5) occurrence of palaeo- and modern evaporite mineralisation. In lowland areas of Shira, the more saline groundwaters and lake waters have a sodium-sulphate (-chloride) composition. Results of thermodynamic modelling suggest that these evolve by a combination of silicate weathering and gypsum and halite dissolution, coupled with carbonate precipitation to remove calcium and bicarbonate ions. An approximately 1:1 sodium:sulphate ratio occurs even in groundwaters from non-evaporite-bearing aquifers. This may indicate the formation of secondary sodium sulphate evaporites (in or near saline lakes or in soil profiles where the water table is shallow), which are subsequently distributed throughout the study area by atmospheric transport. Several urban groundwaters are characterised by very high nitrate concentrations, conceivably derived from sewage/latrine leakage. Received, June 1998 /Revised, May 1999, August 1999 /Accepted, August 1999  相似文献   

20.
淮北某矿区地下水环境质量评价   总被引:1,自引:0,他引:1  
在分析淮北某矿区水文地质条件的基础上,选取S4O2-、Cl-、矿化度、总硬度4个污染因子作为评价因子,以GB/T14848-93《地下水质量标准》为评价标准,分别运用尼梅罗指数法和模糊数学法,对该矿区各主要含水层进行了地下水环境质量评价。评价结果表明,该矿区第一含水层(组)水质较好,适合作为矿区工业用水以及生活饮用水的供水水源,而第二含水层(组)及其以下含水层地下水均需要作适当的处理才可作为饮用水源。  相似文献   

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