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1.
洪国华  梁会圃  王宏珍 《地下水》2005,27(5):365-366
包气带水是地球水体的重要组成部分.研究包气带水的形成及运动规律不仅对阐明地下水的形成具有重要意义,而且是实现农业节水的关键.本文在阐述包气带水特征的基础上,指出了包气带水研究方向:一是包气带中土壤水的调控研究,二是水-气二相流数值模拟研究.  相似文献   

2.
刘鲜民  王现国 《地下水》2009,31(5):79-82
包气带是地下水补给和地下水污染的主要通道,因此包气带的性质直接控制了地下水的污染化速度和程度。以洛阳市区洛河河床岩性(以砂砾石为主)以及由亚粘土、亚砂土、中细砂等介质构成的包气带为研究对象,来分析河床和包气带对污染物的自净能力,并对其天然的自净机制进行了简要的分析,结论如下:洛河河床岩性对各种污染物(NO3-除外)的净化能力均达到90%以上;亚粘土、亚砂土、中细砂等包气带介质层对重金属(Cu^2+、Pb^2+等)有很强的净化能力,而对Cl、Cr^6+净化能力则较弱,在短时间内介质中就达到饱和而失去净化能力;在环境条件相近及水文地质条件基本相同的条件下,包气带厚度与地下水的污染程度呈负相关关系;污水经过包气带发生较强的过滤、吸附、离子交换、生物化学降解等作用,能有效地去除污水中的有害物质,防止地下水污染。  相似文献   

3.
包气带—含水层地下水污染风险评估研究进展   总被引:1,自引:0,他引:1  
包气带—含水层作为地表水和地下水之间水循环和溶质迁移的重要介质,是地球科学领域中的研究热点。以包气带—含水层中地下水污染风险评估为综述对象,从包气带—含水层地下水污染现状出发,总结了包气带—含水层的污染现状、表征、渗流与溶质迁移及其影响关键参数研究等方面的进展,最后分析包气带—含水层地下水污染风险评估存在的问题及今后的研究方向,指出尤其应重点考虑基于逾渗阈值开展地下水污染风险评估研究。  相似文献   

4.
干旱区包气带土壤水分运移及其对地下水补给研究进展   总被引:2,自引:0,他引:2  
包气带是指地表到地下水之间垂直剖面中土壤孔隙没有被水充满、水分处于非饱和状态的区域,是地表水进入地下水的通道。包气带土壤水分运移过程不仅影响到地下水补给,而且与相邻景观之间存在水力联系。评述了干旱区包气带土壤水分运移模拟、地球化学示踪技术、地球物理技术在包气带土壤水分运移研究中的应用、影响包气带土壤水分运移及对地下水补给的因素、包气带水分运移对景观间水分交换的影响等方面的研究进展,提出在未来的研究中,应加强包气带土壤水分运移参数的试验观测及数据库建立、加强包气带土壤水分运移及其对地下水补给的研究,应借鉴地球关键带研究的思路,开展包气带土壤水分运移、溶质运移、地下水补给耦合研究。  相似文献   

5.
包气带增厚条件下地下水补给规律研究   总被引:1,自引:0,他引:1  
伴随人类活动影响的不断增大,地下水位持续下降,包气带厚度增大,改变了地下水的补给条件.为阐明在巨厚包气带中水分运移规律,在河北栾城实验站进行了包气带水分运移监测试验.通过对监测数据的计算和分析,揭示了大水漫灌条件下,灌溉水在包气带中湿润峰和零通量面(ZFP)的运移和形成规律,计算了灌溉水回归补给地下水的水量,并利用达西公式进行验证.试验结果客观准确地反映了在当前人类剧烈活动影响下,包气带中水分运移规律及灌溉水补给地下水的情况,同时通过对包气带水分运移情况进行监测,取得了包气带水分运移的翔实资料和灌溉参数,对于促进农业节水灌溉有重大的现实意义.  相似文献   

6.
当前在开发利用地下水的同时,包气带水分的赋存与运移问题及其对地下水的形成与补给作用,引起了人们的关注。大家知道,饱和带与包气带是地下水同一连续系统中的两个部分,二者不可分割。包气带中水分下渗,其数量与速率决定了地下水的储量与动态,反之,地下水的变化影响着包气带水分剖面及其运移条件。尤其是黄土地区特定的自然地理条件下,  相似文献   

7.
毛乌素沙地植被与地下水关系   总被引:5,自引:0,他引:5  
以植被的种群和盖度、地下水埋深、包气带含水率、地下水矿化度和包气带含盐量等指标,研究毛乌素沙漠腹地地区植被与地下水的关系,确立了研究区优势植被沙蒿(Artemisia)、沙柳(Salix psammophila)和苔草(Carex)的适生地下水埋深、包气带含水率、地下水矿化度和包气带含盐量。研究表明:地下水埋深、包气带含水量对植被种群影响非常敏感,而地下水矿化度和包气带含盐量则为不敏感指标。另外,地下水埋深对以地下水为水分来源的植被盖度较为敏感,而总盖度为不敏感指标。  相似文献   

8.
浅析包气带土壤水分势能   总被引:1,自引:0,他引:1  
陈建锋 《地下水》1998,20(1):33-34,16
研究大气水、地表水、土壤水、地下水四水转化过程,直接关系到国民经济的发展,是开发利用水资源必不可少的一步。包气带土壤水分运动是这一过程中尤为重要的一个环节。阐明包气带土壤水分运动规律,土壤水分入渗、蒸发机理,确定入渗、蒸发量及其影响最大深度,其中起决定性作用的是土水势。本文对包气带土壤水分势能动态规律及其影响因素,从以下三方面加以分析。  相似文献   

9.
包气带在干旱半干旱地区地下水补给研究中的应用   总被引:3,自引:0,他引:3  
在干旱半干旱地区,包气带的溶质和同位素剖面不但可以提供较长时间尺度上的地下水补给信息,而且记录了过去气候变化与环境变化信息。本文基于学科组近10年的研究成果,以鄂尔多斯盆地为例(包括南部的黄土高原和北部的沙漠高原),将包气带和饱和带结合起来,利用多种环境示踪技术,提升了包气带在干旱半干旱地区地下水研究中的潜力,并将其应用到地下水补给历史重建、地下水补给机制确定、植被变化对地下水补给影响评价和地下水污染物全过程示踪中。研究表明,由于在干旱半干旱地区,包气带较厚且补给量有限,地下水和现今的浅表水文过程未达到水力平衡,如在沙漠高原西部,近2 500 a降水尚储存在包气带13 m以浅,地下水是4 000 a以前补给的,其水化学特征与浅部包气带水差异巨大;而在黄土高原,补给量较大,但包气带巨厚,年降水仍需要几十到上百年时间入渗到地下水(但并不意味着没有补给,其土壤水在包气带中平均入渗速率为0.1~0.3 m·a-1),包气带浅部溶质含量较深部和地下水中的高;典型黄土塬区的地下水均不含氚,地下水年龄在几百到上万年。黄土内部层状均匀的土壤质地特征和相对较老的地下水年龄揭示的均匀活塞流入渗是黄土塬区浅层地下水补给的主要方式。黄土高原退耕还林还草和沙漠区植被恢复导致地下水补给呈现不同程度的减少,反映在包气带上表现为溶质含量的增加,可用于定量化确定地下水补给量的变化。本文强化了包气带在干旱半干旱地区地下水补给研究中的作用,在未来地下水资源评价、地下水污染全过程刻画中应得到重视。  相似文献   

10.
地下水污染研究中要讨论的问题很多。本文的主要内容是介绍关于地下水污染含义的各种观点,并提出作者的看法;综合归纳包气带中污染物的各种水文地球化学作用,并介绍监测包气带污染物迁移的各种方法;最后讨论地下水资源区域防护及局部防护的问题,并提出含水层防污性能的分类及地下水供水水源地防护带确定方法。  相似文献   

11.
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   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
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   

14.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

16.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

18.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of  相似文献   

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