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为探究济南市玉符河人工补源对趵突泉泉域的影响,在系统分析泉域水文地质条件的基础上,采用地下水数值模拟软件GMS10.0建立了2012—2014年覆盖趵突泉泉域的地下水流数值模型,通过模型对玉符河补源实施后地下水的径流方向、影响面积以及对泉水位和西郊水源地水位的提升作用进行评估。结果表明:玉符河补源在实际渗漏量为10.52×10~4m~3/d的情况下,玉符河补源水首先沿着炒米店地堑由南向北流,然后再向东、西方向径流。补源后第177 d,补源影响范围基本抵达四大泉群,玉符河补源的最大影响范围为485.79 km~2。玉符河补源对趵突泉、黑虎泉的最大影响水位为0.06 m和0.04 m;对济南西郊水源地的水位起到明显的提升作用,最大值达到0.57m。西郊水位的抬升可以缓解地下水开采对趵突泉水位的影响,减小保泉的压力,也为将来济南百姓重新喝上优质地下水奠定了基础。 相似文献
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区内岩溶地下水的水质特征时间、空间的变化主要是岩溶水的存储、补给、循环径流、开采等条件的变化造成的。岩溶水的补给主要来源于地表水的直接补给、第四系孔隙水的越流补给、大气降水的直接补给及上游的侧向径流补给。 相似文献
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华北平原水资源合理开发利用的思路与举措 总被引：4，自引：0，他引：4
经过几十年的大量开采利用,华北平原地下水资源不仅表现为区域超采和局部严重超采,也暴露出地下水补给源严重萎缩的问题。其主要表现在中西部粗质平原的地下水易补给区,因汇流山地水库强力拦蓄,河道主体补给功能丧失,而在中东部细质平原的径流主产区,因水位埋藏浅和水质咸化,降水径流不能形成对地下水的有效补给,蒸发流失严重。以往实践强调山区水利工程建设而轻视了东部低平原区径流拦蓄利用,重视对高海拔咸水体的改造利用而忽视了对低海拔咸水体的改造利用,强化地表水库建设的重要性而忽略了地下水库的重要性。面对华北平原供水紧张的严峻形势,调整水资源开发战略势在必行,其具体思路是:以千方百计提高降水利用水平为中心,调整和改善水资源开发利用整体布局;以地下水补给调蓄为重点,大力集蓄雨洪水和改造利用浅层水,充分发挥地表水和地下水两大功能作用。其具体举措有:实施山前梯级水坝的地下水库"回灌"工程;实施中东部及滨海淡水蓄水利用工程;实施东部浅层地下水规模化改造开发利用工程。若上述措施得以实施,可使降水利用率从现状的20.65%提高到26%以上,则华北平原供水问题有望获得解决。 相似文献
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随着城市建设的不断加大,地下空间开发程度越来越深,伴随着基坑的开挖越来越深,城市的扩展不可避免地对地下水的补给、径流、排泄条件产生影响,而水文地质条件的改变又反过来影响制约人类的活动,甚至引发工程安全问题。该文以济南某建设项目为例,通过水文地质勘查、地球物理勘探、水位动态模拟、地下水取样等手段,研究分析近年来该建设项目周边地下水补径排条件的改变对区域地下水位的影响,以及水文地质条件的变化对建设项目工程的制约。结果表明,由于地下工程开挖、大气降水、保泉政策等因素影响,地下构筑物的开挖阻断了唯一的排泄通道,该建设项目周边地下水渗流场发生变化,由此造成项目区周边地下水位大幅上升,超过前期设计的抗浮设防水位,并对地下构筑物产生了破坏。研究结果对周边类似建设项目的选址及地下空间的开挖具有一定的指导意义。 相似文献
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王明远 《中国地理科学(英文版)》1993,3(4):376-380
We have made progress in medico-chemical geography as follows: the correlative law of organism with geochemical environment; the geochemico-ecological classification of chemical elements; the types of formative cause of biogeochemical provinces in China; the parabolic correlation between contents of iodine in drinking water and prevalence rate of endemic goiter; the discovery and proof of the low selenium zone in China; the successive discovery of endemic fluorosis of the types of pollution from burning coal, drinking high fluoride tea and high fluoride table salt from the year 1978; the study on chemical geography of schistosomiasis and the compilation of the Atlas of Endemic Diseases and Their Environments in the People's Republic of China. 相似文献
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随着信息社会的发展，新技术和新媒体的出现必然影响学校现代教育的发展。通过阐述发展学校电化教育的应注意的问题，探讨了解决问题的方法。 相似文献
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We used long term monitoring data to evaluate changes in abundance and species dominance of small-jellyfish (collected with zooplankton net whose bell diameter was less than 5 cm) between 1991 and 2009 in the Jiaozhou Bay, China. Zooplankton samples were vertically towed with conical plankton net from near-bottom to surface, identified microscopically, and mapped in time-space using Grapher 7.0 and Surfer 8.0. Results show that the abundance of small-jellyfish throughout the bay had been increasing during 2001-2009 on average of 15.2 ind./m 3 , almost 5 times higher than that between 1991 and 2000. The occurrence of peak abundance shifted from spring to summer after 2000, and two peaks appeared in spring and summer, respectively, after 2005. Both the abundance and the frequency of blooms of small-jellyfish increased after 2000 in the bay. In addition, the biodiversity of jellyfish has increased significantly in recent years with a change in dominant species. Several new dominant species appeared after 2000, including Rathkae octopunctata in winter, Phialidium hemisphaericum in spring, summer, and autumn, Phialucium carolinae in spring, and Pleurobrachia globosa in summer and autumn, while some previous dominant species throughout the 1990s (Eirene ceylonensis, Zanclea costata, Lovenella assimilis, and Muggiaea atlantica) were no longer dominant after 2000. The abundance of small-jellyfish was positively correlated with the density of dinoflagellates, and the abundance of zooplankton. We believe that the changes in smalljellyfish abundance and species composition were the result of eutrophication, aquaculture and coastal construction activities around the bay. Concurrently, seawater warming and salinity decrease in recent decades promoted the growth and reproduction of small-jellyfish in the bay. 相似文献
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刘希林 《中国地理科学(英文版)》1995,5(3):275-287
ＲＥＣＥＮＴＤＥＶＥＬＯＰＭＥＮＴＳＩＮＤＥＢＲＩＳＦＬＯＷＲＥＳＥＡＲＣＨＩＮＩＴＡＬＹＭａｒｃｈｉＬｏｒｅｎｚｏ；ＴｅｃｃａＰｉａＲ．（ＩｎｓｔｉｔｕｔｅｆｏｒＰｒｅｖｅｎｔｉｏｎｏｆＨｙｄｒｏｌｏｇｉｃａｌａｎｄＧｅｏｌｏｇｉｃａｌＨａｚａｒｄ... 相似文献