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1.
关中盆地地下水脆弱性评价指标体系的探讨   总被引:1,自引:0,他引:1  
地下水脆弱性是近几年来出现的新概念,在分析国内外有关地下水脆弱性研究现状的基础上根据关中盆地的地貌、地质、水文地质以及环境问题,探讨了地下水脆弱性的概念,提出了关中盆地地下水脆弱性评价指标体系。  相似文献   

2.
本文在阐明关中盆地环境水文地质条件的基础上,论述了关中盆地潜水化学特征及其成因,并着重对盆地潜水化学变化的几个主要问题,诸如常规组份的升高及水化学类型的改变、潜水硬度的升高、硝酸盐的富集及微量重金属元素的污染等进行了分析。讨论了上述问题的因果及今后工作意见。  相似文献   

3.
采用参数分级评分叠加型指数法对泰安市地下水污染现状进行的评价结果显示 ,泰安地下水已遭受严重污染。地下水污染以地下水中宏量组分、NO-3 、硬度、TDS的迅速上升高以及地下水遭受人为环境物质的污染为主要标志 ;地下水污染主要受地下水系统水文地质结构、纳污河流、污水灌溉及地下水开采控制和影响 ,地下水污染是人类活动影响的结果。  相似文献   

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水资源短缺的鄂尔多斯盆地内地下水遭受硝酸盐(NO3-)污染等问题日益突出,识别盆地不同地下水流系统的NO3-分布规律及其成因,对地下水资源的合理利用与保护具有重要意义。选取鄂尔多斯盆地北部湖泊集中区白垩系地下水系统为研究对象,基于水化学和聚类-主成分分析划分地下水流系统级次,在此基础上对比分析不同级次地下水流系统中NO3-分布特征,综合水化学和环境同位素分析识别多级次地下水流系统中NO3-来源及其潜在过程。研究表明:研究区ρ(NO3-)超出地下水质量标准(GB/T 14848-2017)Ⅲ类水标准的地下水样品集中在局部-中间地下水流系统,其超标率达到28%;区域地下水流系统中ρ(NO3-)均值约为1 mg/L。研究区不同级次地下水流系统中ρ(NO3-)分布特征主要与人类活动影响程度有关,而地下水蒸发富集和反硝化衰减作用对ρ(NO3-)的影响可以忽略。其中,局部-中间地下水流系统受到人类活动产生的污染影响显著,其NO3-污染主要来源于无机铵肥和粪便污水等;区域地下水流系统可能尚未受到人类活动污染,其NO3-来源于天然有机氮矿化。   相似文献   

5.
地下水水质安全性评价是地下水资源保护的关键环节。为了阐明鲁中泰安-莱芜断陷盆地地下水水质安全性,本次研究系统评价研究区地下水水质现状、水质变化趋势和地下水污染风险,并以此为基础开展地下水污染预警分级,揭示地下水水质安全性。评价结果显示,研究区内地下水污染预警等级分为巨警、重警和中警3个级别。其中,巨警区占研究区总面积的21%,表明该区地下水水质极不安全;重警区占研究区总面积的26%,主要分布在巨警区外围约5km范围,地下水水质不安全;其他地区为中警区,占研究区总面积的53%,地下水水质临界安全。该研究可为鲁中地区泰安-莱芜断陷盆地地下水资源保护及合理开发利用提供有力支撑。  相似文献   

6.
以山东省邹城市双村岩溶水系统为研究对象,利用多年水质监测资料对主要离子含量的变化特征及分布规律进行研究比对,分析地下水开采及生活污染对地下水水化学环境的影响,有助于认识在人类生产活动影响下的水化学场时空演化,为地下水合理开发、水源保护提供参考依据。  相似文献   

7.
通过对山西大同盆地内236个孔隙水样的检测分析并与以往水样分析结果对比研究,并结合盆地地下水系统的分布与演化格局,对盆地地下水化学场及其演化问题做出初步分析。研究发现盆地孔隙水的水化学特征作为盆地孔隙水系统的重要属性,受到地形地貌、地层岩性、沉积环境、地质构造以及水文气象等多种因素的影响,其空间变化表现出极强的水平分带变化规律性。  相似文献   

8.
通过对吕梁市城市地下水污染类型及分布、地下水污染特征与分布规律、地下水污染危害程度以及地下水污染的社会影响等方面进行简要阐述,分析得出地下水污染问题的严重性。  相似文献   

9.
地下水污染预警是区域地下水资源保护的重要手段。山东双村岩溶水系统是典型的鲁中南单斜构造型岩溶水系统之一,现开采量39.848万m~3/d,为特大型岩溶水源地。30余年的水质监测数据表明,岩溶水水质逐渐变差、水化学类型变复杂。在查明水文地质条件、污染源调查和长序列水质监测的基础上,构建了有针对性的地下水污染风险评价指标体系,通过全面考虑地下水水质现状、水质变化趋势和地下水污染风险等主要影响因素,采用综合指标法开展了地下水污染预警研究。研究区地下水污染预警为中警区和巨警区,地下水补径排条件、污染源分布以及含水层防污性能是主要影响因素,控制废水排污量、严格执行达标排放以及建立完善地下水水质动态监测网络是控制地下水污染的重要手段。本次构建的地下水污染风险评价指标体系较为合理,预警结果较为可信,对地下水污染预警评价具有一定的借鉴意义。  相似文献   

10.
温度是地下水的固有属性,地下水温度场和动态特征是地下水流系统的外在表现。为揭示地下水开采等人类活动影响下西北内陆盆地浅层地下水温度场特征与地下水流系统的关系,基于多点位、长序列、高精度的地下水温度监测数据,在酒泉东盆地开展了地下水温度场及动态特征研究。结果表明:酒泉东盆地浅层地下水温度9.33~20.77℃不等,平均水温为13.54℃,自地下水补给区至排泄区,沿地下水径流方向,浅层地下水温度逐渐升高;循环深度相近的不同地下水流系统对比表明,浅层地下水温度与地下水动力条件呈负相关,地表水入渗补给大、水动力条件强的水流系统地下水平均温度低,入渗补给小、水动力条件弱的地下水平均温度高;浅层地下水温度动态受自然地下水循环和地下水开采等人类活动共同影响,从山前地下水补给区到中游绿洲区再到下游排泄区,浅部地下水温度动态可划分为4种基本类型,依次分别为河流补给型、水温稳定型、开采相关型、正弦波动型。   相似文献   

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Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.  相似文献   

13.
Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.  相似文献   

14.
正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied  相似文献   

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《山地科学学报》2014,(4):I0004-I0009
<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.  相似文献   

17.
<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by  相似文献   

18.
S 《山地科学学报》2008,5(1):63-72
Livestock behaviour in the Pyrenees includes free grazing and a long resting period that provokes the accumulation of dung and urine in some places,so-called camping areas. The aims of this study were (i) to analyze any change in floral composition,and in nutritional and chemical contents of plants in a livestock camping area; and (ii) to relate the floral composition with soil chemical properties. In a linear transect,five sampling zones were established,from the centre of the camping area to the surrounding Nardus stricta-dominant pasture. The above ground plant biomass and the topsoil were sampled in each zone with 6 replicates per zone. Plant species were classified and weighed to calculate above ground biomass,nutritional and chemical contents,and Shannon diversity and evenness indices. Additionally,soils were sampled in two periods,at the beginning and at the end of grazing period. Soil available nutrients (nitrate,ammonium,phosphorus,potassium,calcium and magnesium),total nitrogen,organic carbon and pH were measured.
Plant chemical contents (protein,lignin and others) were significantly related to the proportions of grasses,legumes and other plants; so,the protein content is positively correlated with legumes plant biomass while lignin content is negatively correlated with grasses. Both plant and soil nutrients increased linearly towards the centre of the camping area. However,the relationship among plant species richness,diversity and evenness relative to its position along the studied transect was bell-shaped. From the outskirts to the centre of the camping area,plants with low nutrient demand were progressively replaced by those with medium and high nutrients demand and by pioneers.
Nardus stricta-dominant pasture has low plant diversity and plant nutrient content as well as a poor soil nutrient availability. The presence of the camping area introduced patches with more soil nutrients and new species in the large spatial scale. However at a small spatial scale,the strong soil nutrien  相似文献   

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文章概略介绍了利用卫星进行定位的原理 ;由卫星信号传播、信号接收和SA政策等引起的理论误差 ;给出了多种快速、高精度定位的工作模式和观测点选择的原则 ;列出了将WGS - 84坐标转换为我国坐标的公式及解算参数的具体方法 ,供读者在GPS工作中参考。  相似文献   

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