茂名市浅层地下水pH值偏低的原因分析

原生地质环境、工业废气 (酸雨 )、酸性工业废水及工业废渣共同造成了茂名市浅层地下水pH值偏低。     

河南省永城市浅层地下水水质污染分区

永城市浅层地下水水量丰富 ,水质良好 ,是一处理想的供水水源。本文运用模糊数学方法对该区浅层地下水水质进行了评价 ,确定了该区的环境背景值 ,并把该区分为 3个区。     

天津滨海新区浅层地下水侵蚀性分区研究

由于滨海新区地下水对基础侵蚀性较严重,故开展了此课题研究。该项目主要是利用已有地下潜水水质分析试验资料,对滨海新区基础侵蚀性分布规律进行研究。     

浅层地下水的腐蚀机理综述

引起浅层地下水病蚀的主要因素是高浓度的腐蚀性离子、溶解的气体及微生物。系统总结了水中各主要盐类,阴、阳离子、腐蚀性气体、生物细菌等,对金属及混凝土桩的腐蚀机理。为合理有效地采取保护措施提供参考。     

淮南市区浅层地下水资源的计算方法

本给出淮南市区浅层地下水的参数、补给和排泄资源的计算方法，且为制定用水方案，进行了多年均衡的计算，结果表明：浅层地下水平均每年还有６５５０万ｍ＾３资源供利用；在干旱年份里动用的储存资源，丰水年可以得到回补；浅层地下水合理位埋深应为３．５ｍ。     

黄河滩地浅层地下水开发利用研究

黄河滩地和河床下蕴藏着较丰富的浅层淡水资源 ,这个淡水资源来源于黄河渗透水 ,经过试验研究 ,初步探明了黄河滩地及河床浅层地下淡水资源的分布规律 ,揭示了这一淡水资源主要接受黄河渗透激发补给 ,评价分析了地下水资源量 ,提出了合理开发利用的取水方式和建议。     

河南省浅层地下水水化学特征研究

为了全面反映河南省地下水环境问题及其严重程度,使已有的环境地质调查成果更好地服务于国民经济建设。本文在充分收集前人环境、水文、地质资料的基础上,以重点城市居住区为研究对象,在地下水问题严重区加密取样、核查,并基于含盐量,划分了氟化物、碘化物、锰、铁以及不同水化学类型的分布范围和分布面积;同时将不同年度含盐量进行类比,找出了各地区地下水环境演化过程和污染原因,总结了原生劣质地下水的成因及存在地区;并对河南省开采运用地下水提出有效、切实可行的合理化建议。     

山东省日照市地下水环境背景值的初步研究

本文初步研究了山东省日照市地下水环境背景值的确定，形成制约因素，以及与地方病的关系，并提出开发保护意见。     

沧州市城区浅层地下水合理开发及利用研究

本文通过沧州城区浅层地下水水文地质条件分析、浅层地下水开采资源量计算及结合沧州城区的实际情况来合理确定地下水位埋深、规范成井技术、浅井与建筑物安全距离等,通过工程实例来加以论证说明井与建筑物的安全距离,为沧州城市浅层地下水合理开发利用提供了科学依据。     

谈沟谷浅层地下水的特性和地下水路堑勘察

结合铁路路堑实例浅述了山区沟谷浅层地下水在补给、径流和排泄等方面的特殊性，并阐述了针对浅层地下水特殊性而应采取的地质勘察方法，列举了由于对浅层水的特殊性认识不足给工程造成损失的实例。     

洞庭湖区堤垸景观研究

堤垸是洞庭湖区最为重要的乡土景观类型,综合了农业生产、水利调控和聚落建设。人们在湖区的淤洲上建设堤垸来控制垸区的水位,以获得生活和生产空间;数百年的堤垸开垦历史,使得洞庭湖区几乎每一寸土地都经过了设计,积累了大量的水土整合经验。从风景园林的视角出发,将堤垸看作一种空间结构和文化表达的结果,而不单纯是水利工程的产物;通过系统分析和图解的方式,探索堤垸景观的空间设计法则,推断和解读这类景观的发生机制和特征。首先,简要阐述了洞庭湖区堤垸的围垦历史,理清了堤垸的发展脉络;其次,总结了湖区堤垸的现状空间分布情况;再次,从水利、垸田和聚落3个空间层,对不同空间层、不同尺度下的堤垸空间及其嵌套式的相互关系进行了解析;最后,总结出洞庭湖区的堤垸景观具有堤垸的更新性、尺度的层级性、形态的整体性等相关特征。上述分析可以使人们对洞庭湖区的堤垸景观有一个较为全面和深刻的理解,并获得堤垸保护与转型的线索。     

污水提标技术在炼化污水处理中的应用

大型桥梁工程由于两岸通视困难,用传统测量方法直接布设大桥工程控制网及进行大桥施工测量非常困难,因此GPS定位技术在大型桥梁工程的施工控制网测量中应用广泛。本文详细介绍了荆岳铁路洞庭湖大桥施工控制网的测量方案及实施情况,在测量中采用了GPS定位技术来建立施工控制网,整个施工控制网的测量包括施工平面控制网测量和施工高程控制网测量。结果表明获得的平面和高程控制测量成果精度均优于二等精度,可满足工程定测和施工测量应用的需要。     

洞庭湖区新石器中晚期聚落时空分异特征及其影响因素

人类文明的发展进程与所处的环境密 不可分,探讨洞庭湖区新石器中晚期聚落时空分 异特征及影响因素有利于深入了解该时期人地 关系的演变,对史前文化遗产保护具有重要的 价值和意义。运用ArcGIS分析工具,结合因子 分析、地理探测器等方法探讨聚落时空变化规 律。得到结论：第一,新石器中晚期聚落倾向于 在地势平坦且距水较近的区域分布。气候特征 依次表现为大暖期、气温下降、气温回暖、恶化 期,聚落集中分布在年降水量1 150~1 250 mm、 等温21~23 ℃区域。三个文化时期可耕地区域主要分布在坡度0~25°,步行距离0~40 min范围内;第二,工具技艺进步为古人生产、生活及交通 提供了便利,聚落文化重心主要为大型聚落城址,且重心由洞庭湖西北向南迁移;第三,聚落选址 主要受地形因素影响,聚落规模空间分布受地形位指数和年均降水量因素的影响,并随时间变化 地形位指数因素的影响力逐渐减弱而年均降水量因素的影响力逐渐增强;第四,随着农业技术的 进步,聚落之间的社会矛盾激化,北方游牧民族南下,中原文化南迁,对长江流域社会文化发展产 生了重要的影响。     

Studies of hexavalent chromium attenuation in redox variable soils obtained from a sandy to sub-wetland groundwater environment

Laboratory experiments were conducted to characterize and quantify the capacity and kinetics of the combined effects of natural attenuation processes, such as adsorption, reduction, and precipitation, for hexavalent chromium [Cr(VI)] in a variable geochemical (i.e. fraction of organic carbon [foc], redox) environment of glaciated soils. Equilibrium attenuation terms: linear sorption (K(d)), estimated capacity, and non-linear Langmuir (K(L), Q) sorption parameters; varied over several orders of magnitude. The pseudo-first-order rate of disappearance of Cr(VI) from aqueous:soil slurries ranged from approximately 10(-5) to approximately 10(-1)/min. An operationally defined kinetic attenuation term, attenuation capacity (AC), describing the quantity of Cr(VI) disappearing from the slurries, ranged from 1.1 to approximately 12 microg Cr(VI)/g soil/7 days. The linear K(d)'s and estimated attenuation capacities were indirectly and directly related to increasing soil pH and foc, respectively. The AC values decreased and increased as a function of increasing soil pH and foc, respectively. The parameters determined in this work were used to evaluate the kinetics, capacity, and stability of chromium attenuation in the sub-wetland saturated soils in Hellerich (2004. A field, laboratory, and modeling study of natural attenuation processes affecting the fate and transport of hexavalent chromium in a redox variable groundwater environment. Ph.D. Dissertation, Department of Civil and Environmental Engineering, University of Connecticut-Storrs) using a statistical simulation framework.     

Erratum to “Effects of intensive urbanization on the intrusion of shallow groundwater into deep groundwater: Examples from Bangkok and Jakarta”

Asian megacities have severe pollution problems in both coastal and urban areas. In addition, the groundwater potential has decreased and land subsidence has occurred because of intensive groundwater pumping in urban areas. To prevent the adverse effects of urbanization on groundwater quality, it is necessary to confirm the changes in groundwater flow and contaminant transport caused by urbanization. We examined the effects of urbanization on contaminant transport in groundwater. The research areas were located around Bangkok, Thailand, and akarta, Indonesia, cities with populations of approximately 8 and 12 million, respectively. Each metropolitan city is located on a river delta and is adjacent to a bay. We measured the water level and collected water samples at boreholes at multiple depths (100 to 200 m) in 2004 and 2006 in Bangkok and Jakarta, respectively. The current hydraulic potential is below sea level in both cities because of prior excess abstraction of groundwater. As a result, the direction of groundwater flow is now downward in the coastal area. The Cl⁻ concentration and δ¹⁸O distributions in groundwater suggest that the decline in hydraulic potential has caused the intrusion of seawater and shallow groundwater into deep groundwater. Concentrations of Mn and NO3⁻-N in groundwater suggest the intrusion of these contaminants from shallow to deep aquifers with downward groundwater flow and implies an accumulation of contaminants in deep aquifers. Therefore, it is important to recognize the possibility of future contaminant transport with the discharge of deep groundwater into the sea after the recovery of groundwater potential in the coastal areas.     

Effects of human activities and urbanization on groundwater environments: an example from the aquifer system of Tokyo and the surrounding area

The Kanto plain that is the largest depositional plain in Japan has the largest urbanized area called Tokyo Metropolitan Area. This plain has experienced extensive groundwater withdrawals for water resources and human induced disasters such as land subsidence in the process of urbanization. Japanese national government and local governments have monitored groundwater levels and settlement of ground surface for about half a century. These data are useful not only for the prevention of these disasters but for the evaluation of the change of groundwater flow beneath the urbanized area. However, few hydrological and hydrogeological studies about the change of groundwater flow in this plain have been conducted until now except for several studies which were limited in areal extent. In this paper, changes of the distribution of hydraulic heads in the central part of this plain are discussed using the long-term groundwater level observation data to evaluate the change of groundwater flow. The temporal changes in the distribution of hydraulic heads in a major confined aquifer (the second aquifer) and the areal extent of the urbanized area for approximately 50 years can be summarized as follows. In the latter half of the 1950s, urban area was limited in the southern region of the study area and hydraulic head gradually declined from the northwest to the southeast in the study area. After the 1960s, urban area extended toward the north and groundwater in the northern part was largely abstracted until the 1980s. As a result, hydraulic heads in this area markedly declined. On the other hand, hydraulic heads in the southern part began to rise because of the restriction of groundwater withdrawals. In recent years, low hydraulic head area has been formed from the northern region to the central region. These results suggest that the groundwater flow which was affected by urbanization (groundwater withdrawals) has continued to change over several decades, even after the regulation of withdrawals, and hence, the continued monitoring of the groundwater environment is important for the sustainable use of groundwater resources.     

洞庭湖区农村既有住宅节能改造措施

根据洞庭湖区气候条件,结合湖区农村建筑能耗现状与农民经济水平,研究了适合湖区当前农村住宅施工技术与经济条件的门窗及屋顶的节能改造措施。     

洞庭鱼龙，江豚清涟—洞庭湖博物馆方案创作构思

洞庭湖博物馆设计以“洞庭鱼龙，江豚清涟”为主题，以融入当地湿地环境，亲近洞庭生态资源作为设计的出发点，以期塑造“洞庭天下水，鱼龙天下馆”之梦想。总体布局遵循“虚实相生，内外一体”的思想 ；建筑造型寓意“江豚清涟”，以形表意，融于自然；设计整合规划、建筑、景观、室内空间，采取适宜技术手段，生态绿色，融入自然。建成后将成为洞庭湖中似鱼似岛、似帆似山的地景式生态湿地博物馆。     

Removal of chlorophenols from groundwater by chitosan sorption

The equilibrium and kinetics of chlorophenol (CP) sorption by chitosan, poly D-glucosamine, were studied under simulated groundwater conditions. Lower temperature, from 25 degrees C to 15 degrees C and then 5 degrees C, markedly decreased the adsorption rates by a factor of 30-53% and 7-22%. Comparison between two types of chitosan, flakes and highly swollen beads, demonstrated that the maximum pentachlorophenol (PCP) uptake capacities in Langmuir and Freundlich models depend on the specific surface area of the particle. Low temperature (5 degrees C) significantly increased the PCP uptake capacity in comparison to higher temperatures (15 degrees C and 25 degrees C). PCP uptake capacity was halved at pH levels higher than 6.5, and NaCl concentrations greater than 1% blocked PCP sorption almost completely. Of five kinds of chlorophenols, i.e. 2,4,6-trichlorophenol (2,4,6-TCP), 3,4-dichlorophenol (3,4-DCP), 2,3-dichlorophenol (2,3-DCP), 2,6-dichlorophenol (2,6-DCP), 3-monochlorophenol (3-MCP), TCP had the maximum sorption efficiency on flake-type chitosan, followed by DCPs, and finally MCP (the three kinds of DCP, with the same elemental compositions, achieved similar sorption performances).     

Groundwater contamination from well points -- an experience from the Norwegian groundwater monitoring network

Until 2005 the observation wells of the Norwegian Groundwater Monitoring Network in Quaternary aquifers were equipped with metal well points with brass lining. A laboratory leaching test using a new well point demonstrated that the well point material (galvanized iron pipe), the brass lining and the solder used to fix the lining could cause substantial contamination of the collected well water with a long list of chemical elements (Sn, Zn, Pb, Sb, Cd, Fe, Cu, Mn and Al), depending on well capacity, contact time water/well point and pH. Because groundwater chemistry is receiving increased attention in groundwater monitoring all wells were equipped with high density polyethylene (HDPE) points during the years 2004-2005. The HDPE points did not return any values above detection in a similar leaching test, with some minor values of Zn being the only exception.