鲁西北阳谷地区浅层高氟地下水化学特征及成因

鲁西北地区是饮水型氟中毒较为突出的地区。选取鲁西北阳谷地区为研究对象,以水文地质调查和取样分析为工作基础,对浅层地下水采用多元统计分析法、地理信息空间分析法及Piper三线图探究了高氟地下水化学特征和赋存特征,结合饱和指数、Gibbs图和氯碱指数以及氟在土壤与地下水的相关关系,从溶解与沉淀平衡、蒸发浓缩和离子交替吸附作用方面分析了氟的来源和高氟地下水成因。结果表明:阳谷地区F^-浓度大于或等于2 mg·L^-1的高氟水分布于地形较高的古河床高地; 地下水F^-浓度由低到高,阳离子则由Ca²⁺、Mg²⁺向Na⁺转变,阴离子则由SO^2-₄和Cl^-向HCO^-₃转变; 阴、阳离子浓度随F^-浓度变化显示不同的规律性,且在F^-浓度大于或等于4 mg·L^-1的高氟水中,这种规律性变化更为明显; 土壤和地下水呈碱性、高HCO^-₃的化学特征以及区域地下水受蒸发浓缩作用影响是高氟水形成的水文地球化学背景条件; 方解石、萤石和石膏的溶解与沉淀平衡以及阴、阳离子交替吸附作用是高氟水形成和分布的主控因素。     

隆尧县高氟地下水的分布特征与利用

依据大量地下水化学分析资料,揭示了高氟地下水的分布规律和水化学特性,并从气候、地貌、地层岩性和水文地球化学环境等方面分析了高氟地下水的形成机理。认为高含氟地层的存在是形成高氟水的基础,地貌、气候和水文地球化学条件是三个重要的控制因素,并建立了地下水中氟含量与相应深度地层氟盐含量的关系式,用于指导低氟地下水的寻找与开发。     

Multi-Rectangular Diagram Concept in Groundwater Quality Assessment and Application in Pakistan

Abstract

The concept of multi-rectangular diagrams (MRD) is introduced to replace many classical and triangular coordinates (Piper diagrams) to examine the multi-variate association of chemical constituents present in groundwater. MRD eliminates the drawbacks of classical trilinear diagrams effectively. Comparison between MRD and the classical trilinear diagram is presented. MRD is used for the assessment of groundwater quality in Chaj Doab area of Pakistan. The differentiated dominant groundwater types in the study area are sodium bicarbonate, calcium bicarbonate and sodium sulfate. Sodium bicarbonate is the most abundant type of groundwater in the central part of the study area.     

某水源地水化学成分相关性分析

针对研究区的水化学特征，进行了水样的水化学分类，并对水样的离子成分进行了相关性分析。相关性分析结果反映了研究区岩溶水发育的一般规律．从而进一步了解了水源地岩溶水循环系统的特征。     

Application of Stepwise Discriminant Analysis for the Identification of Salinity Sources of Groundwater

Statistical analysis can be an important tool to identify and classify different sources of groundwater salinisation. This paper refers to the application of Stepwise Discriminant Analysis (SDA) as an effective technique for the identification of major constituent ratios which can be used for efficiently identifying various salinity sources. The effectiveness of the SDA method was tested on five groups of groundwater samples known for their salinisation. Three were taken from the brackish groundwater of the Nestos River delta, from the geothermal field of Nea Kessani and the brackish groundwater of the western coastal area of Rhodope, in Greece. The remaining two groups were taken from bibliographic sources and they refer to the degraded groundwater of the Wittmund area in coastal NW Germany as well as from the underground brines of Sichuan Basin in China. The method of SDA has demonstrated its effectiveness of classifying different groundwater groups, and its usefull contribution to the groundwater contamination. In this way, possible expensive field investigations and analyses of chemical parameters can be eliminate.     

Seasonal dynamics of plankton populations and phytoplankton photosynthetic activity in a highland fish pond in tropical West Africa

Compared to the East/Central regions of Africa, little research efforts have focused on West African tropical limnology. This study, conducted on a freshwater ecosystem, Panyam fish pond, in the highland region (Plateau State) of tropical West Africa, provides knowledge on the hydrochemical characteristics and seasonal or annual biomass oscillations corresponding to the distinguishable climatic phases characteristic of the region. Physiographic phenomenon ‘Harmattan’ (North‐East Trade Winds) induced low temperature conditions (<11°C) during December to January. Moderately dilute waters are reflected by relatively low ionic content (average conductivity of 77 μS cm^?1), conforming to the category II of African waters, based on the classification of Beadle (1981) . Seasonal algal succession was marked by its abundance relative to the beginning of the rainy season (May to September). The sequence of annual phytoplankton dominance was Chlorophyceae>Cyanophyceae>Bacillariophyceae. The dominance for zooplankton was Rotifera>Crustaceae. The occurrence of fewer Cladocera and Copepoda in the Panyam pond is an observation consistent with the findings for other tropical water systems. These results further support the contention that seasonal or annual biomass oscillations in the tropics are not systematically lower than in the temperate zone. The observed phytoplankton productivity rates (average value of 4.86 g C m^?2 day^?1) are higher than those reported by Talling (1965) for African waters. A considerable proportion of the net production (64.3%) was comprised of gross production (1760 g C m^?2 day^?1). The observed relatively enhanced respiratory values (25.4–41.5%) are characteristic of tropical waters. Further, more robust studies will work to remedy the paucity of knowledge regarding tropical West African limnology.     

神经网络的地下水类型判别系统及其应用

简要介绍了BP神经网络的理论,在此基础上根据任楼矿区含水层水化学特征,建立判别含水层的BP神经网络模型,从而建立了防突水预警系统。实践证明,该神经网络系统对防范矿井突水有重要作用。     

鄂西渝东区建南气田地层水水化学特征及其意义

对建南气田地层水常规组分、微量元素、δD、δ18O、δ34S同位素测试成果的分析表明,该区水化学成分纵向变化不同于其它油田,并非正向型或反向型水化学剖面,彼此之间也不存在同源性,而是存在多套独立、封闭的水化学环境.a)香溪群(T₃x)地层水有着良好的水化学封闭环境,地表水向下交替程度不大;b) 嘉二段以下具有多套独立而封闭的水化学环境,其中飞三段(T₁f3)地层水在燕山晚期—喜山期通过断裂系统与黄龙组(C₂h)地层水发生过水化学交替.      

利用水化学数据判别矿井突水水源方法探讨

系统分析了矿井突水水源及其水化学特征，并着重就利用常规水化学资料进行突水水源判别的各种方法及其应用中的一些问题展开深入的讨论，进而提出了一些新的认识．     

GROUNDWATER AGE INDICATORS FROM PUBLIC SUPPLIES TAPPING THE CHALK AQUIFER OF SOUTHERN ENGLAND

Bulk age determinations, based upon chlorofluorocarbons and sulphur hexafluoride measurements of samples from twenty-one chalk groundwater supplies in southern England, Indicate that waters of relatively recent age predominate In both unconfined and partially confined situations. Water from pumping stations located on chalk below Palaeogene cover can be distinguished hydrochemically, and a likely interpretation is that these supplies are receiving a small proportion of recharge via induced via induced leakage. Whilst water which is abstracted from the chalk always involves mixing processes, for a sub-set of confined supplies, 'piston' flow could be inferred as a dominant mechanism - resulting in bulk groundwater ages of a few decades. Other supplies are the product of complex mixing. Although low-level chlorofluorocarbon enrichment was encountered for half the catchments sampled, they and sulphur hexafluoride appear to provide independent corroboration to microbiological indicators of the presence of rapid recharge.