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1.
水资源(环境)承载力的研究进展   总被引:46,自引:0,他引:46       下载免费PDF全文
概述了水资源(环境)承载力的概念、特征、量化评价方法及其总体研究的进展。强调了系统研究水资源(环境)承载力的重要现实意义。指出了当前研究中的不足,以及有待进一步研究的问题。  相似文献   

2.
生态及环境需水量研究进展与前瞻   总被引:114,自引:5,他引:114       下载免费PDF全文
论述了国内外有关生态、环境需水研究的进展情况,包括研究内容、定量计算方法及其研究成果等。在此基础上,指出目前生态、环境需水研究领域存在的主要问题,从理论和实践两个方面,提出了生态、环境需水今后需进一步研究的课题。  相似文献   

3.
突水是地下工程常遇到的主要和危害严重的工程地质现象。工程实例分析表明,地下工程中大的涌水和突水大多与地质结构面,特别是断裂有关。文中分析了断裂控制地下水赋存和运移的规律,以及可能导致突水的富水优势断裂的特征。由于断裂突水的复杂性和众多的影响因素,将地质机制分析、经验判断和定量指标与评价模型相结合是重要的,也是可行的。文中介绍了一种富水优势断裂的量化分级方法,讨论了相应的预测与防治工程对策。  相似文献   

4.
包气带中裂隙岩体含水量无法用仪器或者实验的方法获取,也无法用理论方法计算,而这部分水对生态复绿和文物保护等的影响不容忽视。为了解决这一问题,确定岩体内气液态水的质量比(α)是关键。在岩体、气态水和液态水组成的开放系统中,当系统内相对湿度达到100%,系统达到局域平衡态。根据热动力学平衡理论,此时系统内气液态水的密度和质量都相等,即液态水和气态水的质量之比为一常数。因此,为了求取α值,文章设计了室内试验,通过对有效试验数据的分析,获取计算α经验公式。试验研究表明:质量比α跟温度t呈指数函数关系;当气态水达到饱和时,液态水的质量远大于气态水的质量。此研究不仅为定量评价包气带中岩体内水汽含量提供一种计算方法,同时对探讨包气带中岩体内气液态水转化规律具有十分重要的参考价值。  相似文献   

5.
国外节水研究进展   总被引:15,自引:0,他引:15       下载免费PDF全文
对国外各行业用水特点和节水新技术、新方法、新措施及先进的政策法规作了重点介绍,并总结了国外节水方面的先进经验及存在的主要问题,指出了我国节水工作应吸取的教训及应借鉴的经验。  相似文献   

6.
This paper, firstly, shows the distribution of arsenic-contaminated groundwater in Samta village. This village, which is in Jessore district in Bangladesh, was chosen as a model village for investigating the mechanism of groundwater contamination. 90% of the tube wells in this village had arsenic concentrations above the Bangladesh standard of 0.05 mg/l. Tube wells with arsenic concentrations of over 0.50 mg/l were distributed in the southern part of the village with a belt-like shape from east to west. Secondly, groundwater distribution is discussed with respect to its flow and the high arsenic zone (As≥0.50 mg/l) agrees well with the drifting zone of the groundwater. Furthermore, arsenic-free water supply systems suitable for a small area in the village have been developed. A pond sand filter (PSF) system which purifies pond water is discussed in this paper. Prior to the construction of the PSF, the water quality in ponds was examined for arsenic levels. The inflow of drainage from the tube wells was found to be the major cause of arsenic contamination of pond water. The PSF installed in Samta is working very well and produces a good quality of treated water.  相似文献   

7.
通过对含煤地层薄层灰岩含水层长观孔、奥陶系灰岩含水层长观孔、斜风井采空区老空水的水位观测及突水水质的化验,认为告成煤矿13071工作面的突水水源主要为薄层灰岩水,斜风井老空水、奥陶系灰岩水有少量参与.其导水通道是工作面内底板存在的贯通裂隙带,通过采用以疏为主,其他为辅的治理方案,煤矿恢复了工作面的正常生产.  相似文献   

8.
Drinking water from Japan (Toyama, Kumamoto, Osaka, and Tokyo Prefecture) and France (Volvic water) was evaluated for taste and health properties using an index based on major and trace mineral content and organoleptic components. Although various reports point to calcium (Ca2+) as a key ingredient imparting good taste and magnesium (Mg2+) and sulfate (SO4 2?) as causing unpleasant taste in drinking water, recent sensory threshold experiments have indicated that other major ions and minerals directly or indirectly contribute to good taste, including potassium (K), silica (SiO2), and phosphorous (P). The present study examined major and trace constituents in water to accurately quantify water taste, flavor, and health effects in good-tasting (Volvic, Toyama, and Kumamoto water) and average-tasting water (Osaka and Tokyo water). Trace metal, volatile organic carbon, non-purgeable organic carbon and total inorganic carbon levels were evaluated as parameters influencing the sensory properties of the drinking water. All of the representative good-tasting water contained higher amounts of tasty minerals (Ca2+, K+, SiO2) and lower amounts of unsavory, rough (Mg2+ and SO4 2?), and bitter (Cl?) minerals. Stiff diagrams of the water samples indicated that good-tasting water was generally bicarbonate (HCO3 ?) type. Seasonal variations in physicochemical parameters did not change the order of abundance of cations and anions but did affect the concentration of various ions present in the water. Trace metals also affected water flavor. Mn facilitates acetaldehyde formation and Fe is associated with polyphenolic oxidation and formation of organoleptic flavor constituents. Trihalomethanes (THMs) may also cause unpleasant drinking water flavors or odors. THMs concentrations for all samples were below 5.7 μg/L, meeting the safety and taste requirements for good drinking water. The Japanese samples were compared against Volvic water, which was used as a standard for good-tasting water. Total dissolved solids concentrations were below 300 mg/L for all specimens, in compliance with World Health Organization guidelines. The results are discussed on the basis of the balance between inorganic major ions and trace minerals and THMs concentration thresholds.  相似文献   

9.
针对中国北方海湾水库间歇来水、连续取水和沉积物动态释盐的特点,建立水量与盐分耦合的数学模型,以青岛拟建的沐官岛水库为例,探讨水位变化条件下混合型海湾水库库水盐分的影响因素、超标风险与达标条件。模拟结果表明,在水库水位连续降低条件下,毫米量级的日蒸发量对库水盐分的累积效应显著。在不利水文条件下,受沉积物释盐、水分蒸发与人工取水的影响,混合型海湾水库长期存在盐分超标的风险。与水位不变时相反,水位降低时库水盐分浓度随着取水量的增大而升高;因此,当库水盐分存在超标风险时,可以通过减少日取水量实现库水盐分达标。为保障安全供水,在海湾水库设计与运营管理阶段,均需要综合考虑水量-盐分因素进行水库的日取水量调算。  相似文献   

10.
11.
Variations in the chemical composition of the surface waters near Khabarovsk are described for the period of 1896–2008. Seasonal variations in the chemical composition of the Amur and Ussuri waters are shown. The hydrochemical characteristics of the Kazakevicheva, Pryamaya, and Amurskaya passages are presented. The results obtained show that the concentrations of the main ions, as well as biogenic and organic substances, depend on the location of the maximal river runoff in the Amur basin. The impact of economic activities in the Middle Amur area on the dissolved matter content in the Amur and Ussuri rivers near Khabarovsk, as well as the distribution of these substance concentrations across the Amur River and the Amurskaya passage, is described. During the 50 years of regular observations, the mineralization of the Amur water in the winter low-water period has decreased by 1.5 times and the organic matter content has increased by 2 times.  相似文献   

12.
黄土高原缺水的地质环境及找水环境   总被引:1,自引:0,他引:1  
文章分析了黄土高原地下水形成的地质环境,认为降水量、地形地貌、岩性构造和地下水循环是造成黄土高原产重缺水的主要因素,地层岩性和新构造运动是影响地下水富集的决定性因素。指出黄土高原基岩风化带潜水的相对富水岩组和富水地段,提出研究含水层的岩性和构造,寻找基岩风化带潜水是解决黄土高原局部地段缺水的较好途径。  相似文献   

13.
熵权法在水资源与水环境评价中的研究进展   总被引:1,自引:0,他引:1  
随着人口增长和经济社会的发展,水资源的供需矛盾日益增多,对水资源进行合理开发、高效利用、优化配置、全面节约、有效保护、综合治理是至关重要的新任务。熵权法是研究水资源可持续利用的重要方法,可以剔除指标体系中对评价结果贡献较小的指标,减少人为因素对于主观权重的影响,其计算结果真实准确,能够客观地反映水资源与水环境的现状,因此被广泛应用于水资源与水环境评价中,从而为水资源的高效利用及水环境的综合评价提供科学依据。本文对熵权法的由来及在水资源与水环境评价中的发展进程进行了探讨,重点对熵权法在水资源量、水资源承载力、水环境质量和水生态环境评价四个方面的应用进行了讨论和总结,并发现熵权法在水资源与水环境评价中有着良好的应用前景;同时,针对当前熵权法在水资源与水环境评价中存在的不足,提出了改进建议,为水资源与水环境评价的研究方向提供了新思路。除此之外,对熵权法的未来进行了展望:熵权法可与其他方法创新结合共同使用,构建合理全面的评价指标体系,在水资源利用发展趋势、时空格局演变等领域推广应用。  相似文献   

14.
The solubility of cyclooctasulfur in water and sea water at various temperatures in the range between 4 and 80 °C was determined. Cyclooctasulfur in equilibrium with rhombic sulfur reacted with hot acidic aqueous potassium cyanide to form thiocyanate anion which was measured by anion chromatography. Sulfur solubility in pure water was found to increase with temperature by more than 78 times: from 6.1 nM S8 at 4 °C to 478 nM S8 at 80 °C. The following thermodynamic values for solubilisation of S8 in water were calculated from the experimental data: K° = 3.01 ± 1.04 × 10−8, ΔGr° = 42.93 ± 0.73 kJ mol−1, ΔHr° = 47.4 ± 3.6 kJmol−1, ΔSr° = 15.0 ± 11.7 J mol−1 K−1). Solubility of cyclooctasulfur in sea water was found to be 61 ± 13% of the solubility in pure water regardless of the temperature.  相似文献   

15.
水资源可利用量计算   总被引:11,自引:0,他引:11       下载免费PDF全文
水资源可利用量是从资源利用的角度,分析流域及河流水系可被河道外消耗利用的水资源量,对流域水系水资源开发利用程度的总体控制,水资源合理配置和水资源承载能力的研究具有实际意义。从阐述水资源可利用量的基本概念入手,提出了地表水资源可利用量和水资源可利用总量的计算方法,计算了全国及水资源一级区的可利用总量,同时分析了我国水资源开发利用的程度、限度和潜力。  相似文献   

16.
北京地区的水资源   总被引:8,自引:0,他引:8  
郑桂森  吕金波 《中国地质》2001,28(4):45-48,37
北京市是中华人民共和国的首都,人均水资源占有量不足400m^3,严重制约着首都经济的发展。北京多年平均降水量626mm,地表水多年平均径流量26亿m^3/a,地下水多年平均补给量39.51亿m^3/a,地下水平均年可供水量26.33亿m^3。这些数据告诫我余,必须开源节流。  相似文献   

17.
We experimentally determined the maximum tension in synthetic fluid inclusions from the difference between the temperatures of homogenization (T h) and spontaneous vapor nucleation (T n). At temperatures of 100–200°C, liquid water may exist at negative pressures of up to 100–150 MPa. Owing to an increase in surface tension, the effect is even more significant in salt solutions and occurs at higher temperatures. A decrease in the linear dimension of fluid phase by an order of magnitude and, correspondingly, a three orders of magnitude decrease in volume (which is proportional to R 3) increase the maximum tension by ~25MPa. Tension in the liquid phase of water-salt systems may be higher than ~200 MPa without cavitation. Metastability of water and salt solutions in small-sized vacuoles generates stresses in the fluid-mineral system resulting in high solubilities of solid phases. An increase in volume due to coalescence of small inclusions or vanishing of metastability results in an abrupt decrease in supersaturation.  相似文献   

18.
Advancements in hydrology proceeded slowly until the late 1800's when new ventures created a surge of interest and accomplishment. Progress waned again until the middle 20th century when an International Hydrological Decade was conceived, eventually receiving wide multinational support from governmental agencies and nongovernmental institutions.Organized by UNESCO, the Decade program was launched January 1, 1965. Participation included 107 nations, six United Nations agencies, and more than a dozen international scientific organizations. The initial program emphasized scientific research, and international cooperation; the second half of the Decade, emphasized technical assistance and technology transfer, largerly through education, training and demonstration.The success of the Decade led to the establishment of the International Hydrological Program, again under the aegis of UNESCO, to continue the work of the Decade indefinitely. The five major program activities, now involving about 90 countries and several international organizations, include: the scientific program, the promotion of education and training, the enhancement of information exchange, support of technical assistance, and the enlargement of regional cooperation.A significant amount of activity related to hydrological data networks and forecasting is carried on in an Operational Hydrology Programme by the WMO, chiefly through its Commission for Hydrology.Other international governmental organizations with a strong interest in water include the UN, the UN Development Programme, the FAO, the WHO, the International Atomic Energy Agency, the UN Environment Programme, the International Standardization Organization, and developmental institutions such as the World Bank.The specialized interests of researchers outside of the governmental structure, are met through association in various scientific and technical organizations which are world wide in scope and membership.Notwithstanding a sometimes bewildering variety of organizations, there certainly exists, for any nation, group, or individual, a demonstrated mechanism for almost any conceivable form of international cooperation in hydrology and water resources.Dr. Heindl, L.A., formerly US Geological Survey, died on October 18, 1978 (see In Memoriam at the end of the paper) before he could finish the final version. His colleagues, James R. Jones, Robert M. Beall and Ennio V. Giusti, Office of International Hydrology, US Geological Survey, Reston, VA. 22092, USA, kindly prepared the paper for publication and wrote In Memoriam. Approved for publication by the Director, US Geological Survey.  相似文献   

19.
Metalloporphyrins have been found in black trona water, a solution of sodium salts of organic acids occurring naturally in the Green River Formation of Wyoming. The porphyrins consist largely of nickel deoxophylloerythrin, a C-33 acid, and two lower methylene homologues, C-32 and C-31 acids, and possibly structural isomers of these. The C-32 acid is noticeably more abundant than either the C-33 or C-31 acids. Minor amounts of nickel etioporphyrins also are present. These porphyrins are believed to have been derived from the chlorophyll α synthesized by algae that inhabited Eocene Lake Gosiute. The transformations to porphyrins occurred under the influence of high pH, a reducing environment, and geological time.  相似文献   

20.
利用地下水库蓄水是吉林省新的有效治水途径   总被引:2,自引:0,他引:2  
杜汉学  常国纯 《吉林地质》2000,19(2):88-94,99
利用地下水库蓄水是治水的一个有效的效途径。这项工作在我国属于起步阶段,在吉林省是一个空白。本文阐述了地下水库的基本概念、蓄水原理、基础条件、国内外现状,论述了吉林省利用地下水库蓄水的基础条件和巨大的蓄水效益远景。建议建设地下水库蓄水示范工程,推广利用地下水库蓄水,以缓解吉林省水资源严重缺乏的局面,并能大大提高水利化程度 。  相似文献   

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