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221.
The Kali-Hindon is a watershed in the most productive central Ganga plain of India. The whole area is a fertile track with
sugarcane being the principal crop. Systematic sampling was carried out to assess the source of dissolved ions, impact of
sugar factories and the quality of groundwater. Thirty-six samples were collected covering an area of 395 km2. The quality of groundwater is suitable for irrigational purposes but is rich in SO4 which is not best for human consumption. Graphical treatment of major ion chemistry helps identify six chemical types of
groundwater. All possible species such as Na–Cl, K–Cl, Na–HCO3, Na–SO4, Ca–HCO3, Mg–HCO3, Ca–SO4 and Mg–SO4 are likely to occur in the groundwater system. The most conspicuous change in chemistry of groundwater is relative enrichment
of SO4. The interpretation of data reveals that SO4 has not been acquired through water–rock interaction. The source of SO4 is anthropogenic. Sugar factories alone are responsible for this potential environmental hazard. 相似文献
222.
Geophysical and hydrochemical surveys were used to investigate the hydrogeological conditions in one of the Río Sucio microbasins, in central Nicaragua. Zones of vertical structures (i.e. fractures and quartz veins) and weathering were mapped using Continuous Vertical Electrical Soundings (CVES), as such zones are of major importance for groundwater transport. Water from the springs was analysed to determine concentrations of major ions and heavy metals. Low ion concentrations and 18O analyses indicate that the springs occur close to their recharge areas and there is a relatively rapid groundwater circulation. Mercury (Hg) content in the springs was low, while comparatively high amounts of lead (Pb) were found. The results presented here demonstrate the important function of weathering and tectonics in the occurrence of groundwater systems in the basin. Hg and Pb found in the springs’ water reveal the existence of an increase in pollution sources disseminating in the area. More than 100 years of using mercury in the gold-mining industry and releasing wastes into rivers has affected water quality and ecosystems. Further investigations are needed in this area to determine the groundwater vulnerability to this pollution as this resource may be needed in the future.The online version of the original article can be found at 相似文献
223.
Olivier Hébrard Séverin Pistre Nicolas Cheynet Jean Dazy Christelle Batiot-Guilhe Jean-Luc Seidel 《Comptes Rendus Geoscience》2006,338(10):703-710
The origin of chloride-rich karstic spring waters representative of the Languedoc-Roussillon region has been investigated with a hydrochemical approach. To this end, the major and trace elements most often used in the study of saline environments have been considered (Cl, SO4, Br, B, Li). This study allowed distinguishing the different end-members of the various chloride-rich karstic spring waters (evaporitic, marine, geothermal). Associated with the Cl, Br and B contents, the Li/SO4 ratio appeared as a relevant tracer for the determination of the origin of lithium and by extension of the considered waters. To cite this article: O. Hébrard et al., C. R. Geoscience 338 (2006). 相似文献
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The geothermal water hydrochemistry and isotopic characteristics of boreholes in the Suijiang-1 well in Yunnan Province were studied based on the actual drilling geology, regional geological structure and hydrogeological conditions. The analysis results show that the geothermal water is SO4-Ca?Mg type, the recharge elevation is 1 381-1 646 m, the recharge source is atmospheric precipitation, the geothermal reservoir temperature is 42-45 ℃, and the geothermal water is controlled by lithology and geological structure conditions of study area. Atmospheric precipitation enters the groundwater circulation system through the surface karst form of the Wujiaobao anticline, northwest-southeast tensile faults, fissures and karst depression, and geothermal water formed through the rising deep cycle water temperature, then blocked by the double rivers’ fault zone and drilling explosion. 相似文献
226.
227.
Groundwater and lake evolution in the Badain Jaran Desert ecosystem, Inner Mongolia 总被引:17,自引:0,他引:17
The amount and timing of aquifer recharge and the evolution of lakes and groundwater in the south-eastern Badain Jaran desert of Inner Mongolia, with high megadunes, has been investigated using stable isotopes and hydrochemistry. Unsaturated zone moisture profiles down to 22 m have recorded recharge over 1185 years. Small but finite amounts of recharge are recorded with mean recharge rates of 0.95-1.33 mm year?1, determined using a chloride mass balance technique. The unsaturated profile also acts as a unique archive of hydrological and climate change. Before 1300, it was relatively dry but distinct wet periods may be recognised during 1340-1450, 1500-1610 and 1710-1820. Since the mid 1800s, the climate shows a trend towards greater aridity. The interdune lakes are generally fresh but locally, hypersaline lakes are found in juxtaposition. This implies that in general, the lakes have low residence times and flow back into the dune system, but sedimentary obstruction locally prevents outflow and extreme evaporation occurs. The stable isotope records show that the lakes are fed by palaeowaters which on the basis of other proxy data must predate the Last Glacial Maximum. Their recharge source is problematic but most likely this derives from a diminishing water table extending some 30 m south to the Yabulai Mountains. 相似文献
228.
生态补水是维持和改善白洋淀生态环境的重要途径.为研究生态补水对白洋淀水环境的影响,分别在补水前与补水后采集淀水、河水及地下水样品,分析区域地表水和地下水水化学特征.结果表明:(1)白洋淀补水前、后地表水与地下水的水化学组成中Na+为主要阳离子,补水后阴离子以HCO3-为主,淀区南部地表水电导率高;补水后地表水与地下水Ca2+、Mg2+和HCO3-浓度显著增加,水体电导率降低.(2)补水前地下水为Na-HCO3型水,地表水主要为Na-Cl·SO4及Na-Cl·HCO3类型;补水后地表水与浅层地下水向Ca·Mg-HCO3型演化,深层地下水水化学类型基本保持不变.(3)生态补水使白洋淀水位升高,淀区水面积增大,缓解了水资源短缺的问题;同时也使浅层地下水水化学组成发生改变,而深层地下水暂未受到影响.生态补水后,受稀释和混合作用的影响,水体Na+、Cl-和SO42-浓度显著下降,Ca2+、Mg2+及HCO3-浓度增加.在白洋淀生态补水中应"先治污,后补水",以减少补水过程中污染物向淀区的运移,还应注意区域地下水位上升过程中的阳离子交换及水岩相互作用,为合理调配生态补水及改善白洋淀生态环境提供科学依据. 相似文献
229.
油气运移、聚集与地下水动力场的形成和演化密切相关,随着盆地的形成与演化,地下水动力场也有形成、发展和消亡的过程。准噶尔盆地玛湖—盆1井西复合含油气系统侏罗系现今地下水动力场具有不对称性:西北缘和陆梁隆起以北地区发育向心流,凹陷内地下水动力表现为滞流,仅在莫索湾凸起及其以南地区发育弱离心流。研究区侏罗系地下水化学分布表明在盆1井西地区曾发育离心流,结合盆地沉积演化分析,研究区侏罗系地下水出现滞流的时间应该在古近纪。 相似文献
230.