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地下水管理模型在我国实践中存在问题的讨论 总被引:4,自引:2,他引:4
文章指出我国地下水资源管理方面的成绩,同时讨论了近年来在这一领域中存在的一些倾向.作者对地下水资源进行优化管理不同于纯经济领域管理的特点,地下水管理模型建立中如何正确处理当地地下水初始流场,求解响应矩阵元素以及选择激励脉冲大小等问题,分别提出了自己的看法. 相似文献
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我国地下水开发利用状况及其分析 总被引:8,自引:0,他引:8
分析了我国地下水开采状况,通过对比地下水资源量、可开采量、实际开采量分析地下水开采情况,论述了由于地下水超采造成的生态环境问题,提出了加强地下水管理的意见和建议。 相似文献
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对我国地下水监测工作的分析 总被引:4,自引:2,他引:4
地下水监测信息是地下水合理开发、水资源管理和生态环境保护的重要基础。提出了目前地下水监测工作还较薄弱,并强调了加强地下水监测工作的必要性。阐述了我国地下水监测现状及存在的问题,对今后地下水监测、分析工作提出了建议。 相似文献
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本文针对我国北方井灌区普遍存在地下水资源不足的问题,以供水总费用最低为目标,研究建立了区域地下水、水面水联合利用的非线性规划管理模型。并将该模型在商丘管理区进行了实际应用,对当地合理开发利用地下水资源和引黄工程规划具有重要的参考价值。 相似文献
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受自然地理、气候环境和经济社会等影响,不同地区、各国之间对地下水的开发利用程度不同,对地下水的监测管理差别很大。作者在系统收集整理欧美等主要国家地下水监测管理的有关论文和成果基础上,结合多年从事地下水工作的实践与心得体会,根据我国地下水监测与管理的实际情况,就我国与欧美等主要国家在地下水监测网布设、监测技术方法、监测数据处理和信息成果应用、地下水法规管理等方面的做法进行系统的对比和分析,以期寻找差距、借鉴经验,并对如何提高和促进我国地下水监测与管理工作进行了展望。 相似文献
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地下水专业档案管理的几点思考 总被引:3,自引:0,他引:3
地下水专业档案是地下水工作者在进行地下水管理和地下水监测活动中积累的宝贵财富,是进行地下水管理和水利建设重要的参考依据,随着我国地下水资源管理的深入开展,地下水档案在此领域内所起的作用日益明显,同时在国民经济建设中也发挥着不可替代的重要作用.通过多年地下水专业档案管理的实践,从地下水专业档案的管理和利用的角度,对其内容、重要性、存在问题、管理方法等多方面做了阐述与探讨. 相似文献
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地下水开发引起的环境问题与治理 总被引:24,自引:4,他引:24
我国北方地下水超采地区,引发了地下水位持续下降、地面沉降、海(咸)水入侵和地下水质污染等问题。而在尚未或很少开发利用地下水的河水灌区,仍然存在着土壤次生盐碱化问题。治理地下水环境问题,要加强对水资源的管理,在井灌区拦蓄降雨径流及汛后河水回补地下水,在河水灌区积极开发利用浅层地下水,利用地下微咸水及经过处理的污水发展灌溉,治理污染源防治地下水污染,提高用水效率,采取农业综合节水技术,控制和减少地正点水开采量,并需跨流域调水补源。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引:4,自引:0,他引:4
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species. 相似文献
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Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozach Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003). 相似文献
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正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level 相似文献
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正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7), 相似文献
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正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci- 相似文献
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正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli- 相似文献
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正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.) 相似文献
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正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861 相似文献