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怀柔应急水源地自运行以来一直续采至今,由于连续干旱和多年的超设计规模运行,导致区内水文地质条件发生了较大变化,为保证其"应急供水"的能力,具备随时启动供水的功能,结合南水北调水源进京的机遇,从资源回补涵养和供水系统的热备运行两方面开展研究工作。在综合分析区域水文地质条件和研究多年地下水动态变化规律的基础上,利用地下水数值模型对怀柔应急水源地在不同开采条件下的回补方式和效果进行模拟,拟定了南水北调进京后区域水资源人工回补方案及应急水源地的热备运行方案,并模拟预测了水源地热备运行和地下水涵养效果,为怀柔应急水源地可持续供水提供科学依据。分析结果表明:南水北调水源进京后,怀柔应急水源地可采用夏季高峰集中供水与日常保压相结合的"集中开采"方案和日常"稳压开采"方案。 相似文献
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在唐山丰南地区进行煤田钻探施工时,由于地层裂隙发育,漏水十分严重,给钻探工作带来了许多的困难,甚至造成钻孔坍塌等事故,导致无法进行正常的生产施工。以往多用水泥、惰性材料和有机化学材料等进行堵漏,但效果欠佳。本次施工根据地层漏水的情况及特性,选用了吸水膨胀树脂进行堵漏,依据吸水膨胀树脂的高膨胀率、高强度的特点,使用了灌注法和岩心管投送法综合进行堵漏。结果表明,使用吸水膨胀树脂进行堵漏后,地层裂隙被吸水膨胀树脂完全封堵,堵塞了冲洗液的漏失通道,效果非常理想,满足了正常施工钻进的要求。 相似文献
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基于2008~2012年水质水位数据,分析水位变化下的鄱阳湖水质时空变化特征,并定量研究水位变动对水质的影响。结果表明:(1)鄱阳湖水质自2007年起呈恶化趋势,主要在水位涨落下湿地植被生物净化作用强弱转换影响下,丰水期水质好于枯水期。但有时因降雨初期非点源污染加剧,水位上升而水质下降;(2)水质沿主航道水流方向从主湖体东南部到入江水道逐渐好转,主要受乐安河、信江等入湖河流携污影响,同时受到滨湖城镇排污、采砂加剧内源污染释放等的影响;(3)星子站水位每上升1m,鄱阳湖全湖Ⅰ~Ⅲ类水比例提高6.2%。 相似文献
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针对合肥市水资源现状,分析合肥市水资源特点。结合节水型社会建设的要求,采用相应的定额,预测分析了各行业需水量和供水量,对合肥市2015和2020年的水资源供需平衡进行了二次分析。结果表明:在一次平衡方案下,到2015年,合肥市仅在95%特枯年份下缺水,缺水度为19.16%,水资源基本能满足社会经济的发展。至2020年,合肥市在不同保证率年份下均有缺水,其中,50%频率平水年份的缺水度为3.1%,75%枯水年份的缺水度为4.34%,95%特枯年份缺水度为13.09%,表明未来合肥市水资源紧缺将会成为制约社会经济发展的"瓶颈"。在二次平衡方案下,合肥市仅在2015年和2020年95%特枯年份下有少量缺水,缺水度分别为7.6%和10.21%。最后提出相应的建议,为保证合肥市经济社会、可持续地发展提供科学的依据。 相似文献
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吉尔吉斯斯坦水资源及其开发利用 总被引：3，自引：0，他引：3
吉尔吉斯斯坦共和国地处中亚中心,山地众多,山脉纵横,冰川广泛发育,水资源十分丰富,是中亚五国的"水塔",控制着中亚五国的水资源命脉.吉尔吉斯斯坦经济社会发展潜力巨大且发展意愿十分强烈,研究其水资源及开发利用对找寻妥善的中亚水资源问题解决之道具有十分积极的意义.分析介绍了吉尔吉斯斯坦自然地理以及与水资源形成有关的气候、地形地貌和冰川融雪概况,评价了吉尔吉斯斯坦水资源总量.然后在阐述吉尔吉斯斯坦独立以来至今的社会经济发展概况的基础上,分析介绍了其主要水资源开发工程与水力发电、用水量变化,并对吉尔吉斯斯坦水资源开发利用中存在的主要问题进行了深入剖析. 相似文献
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G. E. Oteze 《Environmental Geology》1981,3(4):177-184
With the limited data available, the components of the hydrologic cycle of which Nigeria's water resources form a part cannot
be adequately quantified. However, some assessment of the water “reserves” of the surface and underground water sources indicate
that there are large supplies that can be developed in Nigeria.
The exploitation of Nigeria's water resources is in an early stage. Despite the progress that has been made in water supply
development since the first waterworks in Nigeria was commissioned in Lagos in 1915, many Nigerians still have no access to
a modern water supply. Water shortages exist periodically in almost every major town and are present in many rural areas of
the country much of each year.
New water laws are needed, as is the definition of the powers of the different water authorities, viz., the Federal Ministry
of Water Resources, the River Basin Authorities, and the States' Water Boards. The goals of the water policy must be to make
available enough good quality water for domestic uses and to exploit enough water for the use of rapidly growing industries
and the year-round needs of agriculture, thereby lessening the adverse effect of the dry season. 相似文献
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Water in Albitic Glasses 总被引：2，自引：1，他引：2
Infrared spectroscopy has been calibrated to provide a preciseand accurate method for determining the concentrations of molecularwater and hydroxyl groups in hydrous albitic glasses. At totalwater contents less than 4 wt.%, most of the water is dissolvedas hydroxyl groups; at higher total water contents, molecularwater becomes the dominant species. For total water contentsabove 4 wt.%, the amount of water dissolved as hydroxyl groupsis nearly constant at about 2 wt.% and additional water is incorporatedas molecular water. These trends in the concentrations of theH-bearing species are similar to those observed in other silicateglasses using infrared and NMR spectroscopies. The ratio ofmolecular water to hydroxyl groups at a given total water contentis independent of the pressure and only weakly dependent onthe temperature of equilibration. Molecular water and hydroxyl group concentrations in glassesprovide constraints on the dissolution mechanisms of water insilicate liquids. Several mixing models involving homogeneousequilibria of the form H2O+O2– = 2OH– among meltspecies in albitic melts have been developed. These models canaccount for the measured species concentrations if the effectsof non-ideal behavior or mixing of polymerized units are included,or by allowing for several different anhydrous species. We used two thermodynamic models of hydrous albitic melts tocalculate phase equilibria. The first assumes that Henry's lawholds for molecular water in albitic liquids; i.e. that theactivity of molecular water in the melt is proportional to itsmole fraction as determined by infrared spectroscopy. The seconddescribes the speciation and thermodynamics of hydrous albiticmelts using the formalism of a strictly regular solution. Thesemodels can account reasonably well for the position of the vapor-saturatedsolidus of high albite and the pressure and temperature dependenceof the solubility of water in albitic melts. To the extent thatthese models are successful, our approach provides a directlink between measured species concentrations in hydrous albiticglasses and the macroscopic thermodyn amic properties of theNaAlSi3O8-H2O system. 相似文献
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Water solubility in orthopyroxene 总被引：7，自引：0，他引：7
The solubility of water in pure enstatite was measured on samples synthesized at 1,100 °C and pressures to 100 kbar. Enstatite crystals were grown under water-saturated conditions from a stoichiometric mixture of high-purity SiO2 and Mg(OH)2. Water contents were calculated from polarized FTIR spectra measured on oriented single crystals. The water solubility in orthoenstatite increases with pressure to 867ᆷ ppm H2O by weight at 75 kbar. At 100 kbar, in the stability field of high-clinoenstatite, a water solubility of 714ᆷ ppm was observed. The water solubility in enstatite at 1,100 °C can be described by the equation cH2O=AfH2O exp(-P(V/RT), where fH2O is water fugacity, A=0.0204 ppm/bar and (V=12.3 cm3/mol. The infrared spectra of the hydrous enstatite crystals show a sharp, intense band at 3,363 cm-1 and a broad, weaker band at 3,064 cm-1. Both bands are strongly polarized parallel c. Most likely, pairs of protons attached to non-bridging oxygen atoms substitute for Mg2+. In order to investigate the effect of chemical impurities on water solubility in enstatite, an additional series of experiments was carried out with gels doped with Al, B, or Li as starting material. Whereas, the presence of Li and B had no detectable effect on water solubility, the addition of about 1 wt% Al2O3 increased water solubility in enstatite from 199 to 1,100 ppm at 1,100°C and 15 kbar. In the infrared spectra of these aluminous samples, additional bands occur in the range from 3,450 to 3,650 cm-1. Similar bands are also observed in natural, aluminous orthopyroxenes and are most likely caused by protons coupled with Al according to the substitution of Al3++H+ for Si4+. A series of hydrous annealing experiments on a natural, gem-quality aluminous enstatite from Tanzania yielded water solubilities generally consistent with the results from the synthetic model systems. The results presented here imply that pure enstatite has a similar storage capacity for water as olivine; however, aluminous orthopyroxenes in the mantle may dissolve much larger amounts of water comparable with the entire mass of the present hydrosphere. Moreover, the mechanism of aluminum substitution in orthopyroxenes, i.e., the distribution of Al between tetrahedral and octahedral sites, may be a potential probe of water fugacity. 相似文献
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N. Birdi 《GeoJournal》1997,41(2):181-191
The water problem in Malta reflects to a significant extent water problems in the rest of the Mediterranean region. Rising water demands have resulted in increasing levels of production. Groundwater resources have been exploited beyond their sustainable yield resulting in water shortages, and salinity levels in groundwater, and ultimately tapwater, have risen to unacceptable levels for human health, and in some cases agriculture and industry. Increasing levels of pollution, mainly from agro-chemicals, have also caused a deterioration in groundwater quality, resulting in unacceptable concentrations of nitrate compounds in tapwater for certain settlments. The competition for good quality water often leads to conflict between consumers and between consumers and the Government. To try and curb groundwater extraction and the poor quality of tapwater, the Maltese Government has resorted to large scale desalination by Reverse Osmosis. Unfortunately the nature of the distribution system is such that there is an inequity in the quantity and quality of water supplied. Certain settlements receive little or no water, usually of relatively poor quality, for long periods, while others receive large amounts, usually of the relatively good quality Reverse Osmosis water. These problems and their causes are discussed and solutions are briefly considered. 相似文献
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以用水为主体的水质水量结合水资源评价方法 总被引：14，自引：0，他引：14
针对以往水资源评价中水质、水量分开评价的不足,结合北方地区的实际,提出了一种以用水为主体的水质水量结合评价方法。 相似文献
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"四水"转化研究综述 总被引：6，自引：0，他引：6
“四水”是指大气水、地表水、土壤水和潜水,“四水”之间的相互转化关系研究,对水资源评估、供需预测、合理开发利用水资源和节水灌溉都有十分重要的意义。本文总结前人在八个8方面“四水”两两之间相互转化的研究成果．归纳了“四水”转化研究存在的问题,讨论了未来的研究重点。 相似文献
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自然界水循环中的水量平衡原理与干旱研究 总被引：1，自引：1，他引：0
概述了国际、国内干旱研究概况。指出区域多年平均降水量的多少,反映了区域中水资源对生态、经济发展承载力的大小。农业生产中把防止土壤蒸发措施叫抗旱;水利建设中拦河筑坝、引水灌溉、凿井汲水,叫兴修水利抗旱救灾。因此干旱的实质是径流消退、土壤蒸发自然衰减并达到区域内水资源对生态和经济发展的承载能力下降到某一限度或阀值的称谓,如人们感官中的小旱、大旱等。根据径流消退公式和土壤蒸发衰减曲线,参照大风、地震研究方法,输入降水、逐日蒸发观测值,即可成功实现统一干旱标准的实时旱情监测。 相似文献
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张掖市经济用水与水资源社会性稀缺 总被引：1，自引：1，他引：0
在投入产出理论的基础上,建立了价值-实物混合型的水资源投入产出模型,以张掖市为例,从各产业部门的用水特征、各产业部门间的水关系以及地区商品贸易等方面系统地分析了造成水资源稀缺的社会经济原因.结果表明:尽管张掖水资源短缺,但它却拥有一个较强耗水能力的经济体系,其经济系统运行对水资源的需求几乎是其当前可用自然形态水的两倍,远远超出其水资源供给能力,对当地有限的水资源产生了巨大的压力;各产业部门的用水特征及部门间的投入产出关系决定了张掖市经济生产对水资源产生的压力难以通过贸易的形式转移到其它富水地区,然而其贸易结构却造成每年都有相当数量的水资源随商品以虚拟水的形式流向外地,并最终导致了张掖市水资源的社会性稀缺. 相似文献
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提高水价对水资源需求的影响分析——以华北地区为例 总被引：29，自引：2，他引：27
中国已决定在3年之内把目前严重偏低的供水价格提高到保本乃至微利水平,这意味着华北地区农业供水价格将从目前的0.03元/m3左右提高到0.2元/m3～0.3元/m3,工业用自来水价格将从0.50元/m3～1.50元/m3提高到3.0元/m3～4.0元/m3,生活用水价格将从0.30元/m3～1.00元/m3提高到1.00元/m3～2.50元/m3。如此大幅度地提高水价,将对华北地区的水资源需求产生强烈的抑制作用,相对于原来预测的水资源需求量,水价提升将使水资源需求量减少25%～50%,达132～250亿m3,至少相当于“南水北调”中线和东线两项工程调往黄河以北的水量。显然,理顺水价具有很大的节水潜力。 相似文献