安徽省淮北地区裂隙岩溶水安全开采潜力分析

安徽省淮北地区是水资源严重紧缺的地区。地下水资源是本区供水水源之一,其中区内的裂隙岩溶水为淮北地区的城市生活及工业用水提供了巨大支撑。通过建立人工神经网络,以相山濉溪徐楼岩溶水源地为典型区,对淮北地区裂隙岩溶水进行安全开采潜力评价。评价结果表明,淮北地区裂隙岩溶水安全开采总量为21 458.61×104m3,具有一定的开采潜力。     

GASAPF方法在徐州市裂隙岩溶水资源管理模型中的应用

本文首次将GASAPF(基于遗传算法的模拟退火罚函数方法)应用于求解条件复杂的、大面积的徐州市裂隙岩溶水资源管理模型。徐州市是以裂隙岩溶水作为主要供水水源的工业城市，针对徐州市地下水长期无节制开采和管理不善而引起的多种环境地质问题，建立了研究区裂隙岩溶水资源的管理模型，并运用GASAPF方法求解，为今后合理开采研究区裂隙岩溶地下水资源提供了科学依据。同时通过分析优化结果的合理性，进一步证明GASAPF方法适用于条件复杂的大面积地下水资源的优化管理，完善和验证了GASAPF方法的实用性。最后，根据本次研究经验指出了GASAPF方法求解复杂系统管理模型时需要注意的问题。     

黄河悬河段影响带远景水源地可采资源评价

在简要介绍河南省黄河影响带水文地质条件的基础上，运用FEFLOW软件建立了研究区三维地下水流模型，计算出地下水多年平均补给量为28．35亿m^3/年，可开采量为19．43亿m^3/年。首次选择了9个水源地的有利开采地段，并通过地下水模型评价，在新增水源地地下水允许开采量133万m^3/年的条件下，预测浅层地下水位最大降深小于20m，开采5—10年后地下水趋于稳定，新增允许开采量的62．58％来自黄河水的补给。研究表明，黄河对研究区地下水具有重要的补给作用，远景水源地地下水允许开采量是有保证的。     

韶关市地下水资源研究

韶关市位于广东省北部，地貌以中山、低山、丘陵及岩溶准平原为主。地下水有基岩裂隙水 、岩溶水及松散岩类孔隙水三大类。对其进行天然资源量、可开采资源量、可有效开采资源量、储存资源量及开采潜力评价，认为韶关市地下水资源分布极不均匀，含水量一般为贫乏—中等，局部丰富，可开采潜力为中等—大。岩溶盆地区地下水适宜采用群井开采和作为集中供水水源地。      

大型抽水试验在就城电厂水源地裂隙岩溶水资源评价中的应用

为了保证永城电厂水源地地下水资源的评价精度，对隐伏的寒武－－奥陶系灰岩裂隙岩溶水进行大型抽水试验，大型抽水试验查明了奥陶系岩裂隙岩溶含水层组的水地质条件，为精确评价该水层组水资源量提供了可靠的依据。     

焦作矿区裂隙岩溶水优势流形成机理研究

本文根据优势面分析原理对焦作矿区裂隙岩溶水优势流形成机理进行了比较系统地研究，分析了优势结构面控水特征和规律。抽水试验实例以及数值模拟结果均表明裂隙岩溶水运动存在优势流，利用综合优势判断裂隙岩溶水优势流方法实用、可行。结论对于基岩矿坑涌水量数值计算或用数值法进行裂隙岩溶水资源评价时参数正确分区具有重要的参考价值。     

广西石山地区岩溶水资源的基本特征和开发利用

根据地质、水文地质条件,把广西石山地区岩溶水资源划分为“暗河型”、“裂隙溶洞型”和“溶隙网络型”3种类型,并论述了各类岩溶水资源的基本特征和开发利用问题。提出了对岩溶水资源评价的观点。     

贵州修文县陶家龙潭水源地水文地质特征

为了研究贵州省岩溶区水源地水文地质特征,以修文县陶家龙潭水源地为研究对象,结合水文地质测绘等调查方法及岩溶地下水的发育规律,得到其地质概况及岩溶发育影响因素、边界条件等特征。划分其隔水边界条件的依据主要为:隔水边界阻水性质、边界沿线岩溶现象发育情况、地下水出露点,并以地形分水岭为依据研究其补给边界。研究表明:水源地发育区域具有独立的水文地质单元的特征;陶家龙潭水文地质单元的发育主要受岩性和裂隙构造的影响;排泄形式主要为岩溶泉和人工开采,并最终排泄于地表河流;水源地地下水水化学类型为HCO3·SO4—Ca·Mg水,适合作为饮用水源。     

北京房山岩溶水应急水源地地下水流数值模拟及预测

为分析北京房山岩溶水应急水源地的持续开采能力,在概化区域水文地质条件的基础上,建立了区域地下水流数值模型,模拟水位与实测水位拟合较好。利用验证后的模型,进行了枯水年条件下三种开采方案的预测评价。结果表明,以现状开采量持续开采至2014年末(2 332×104 m3/a),岩溶水系统处于动态平衡状态,地下水位没有明显变化;若增加一倍开采量,则地下水位下降速率为3.17m/a,泉水流量减小;开采量为7 300×104 m3/a时,地下水位下降速率增大到8.96m/a,且泉水出现断流。维持现状开采量是合理的持续开采方案。研究结果为应急水源地持续开采提供了依据。     

原阳县地下水开采及保护对策

原阳县地下水分为浅层水、中深层水和深层水,分析了三种地下水的分布情况、水质状况和存在的问题,尤其是浅层水总硬度含量超标的问题。经过计算,适合开采利用的中深层地下水允许开采量约为3万m3/d。提出了原阳县水源地开采和水资源保护的对策:建立健全水源地的保护机制,建立卫生防护带,制定水源地生产井的施工工艺,做好水源地开采监测工作等。     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

Serial discontinuities in a Rocky mountain river. I. Distribution and abundance of plecoptera

Samples were taken year-round at eleven sites along the altitudinal profile (2900-1400 m a.s.l.) of the Gunnison River, a 329 km tributary of the Colorado River, to document the distribution of the Plecoptera and to evaluate responses to hypolimnial-release dams in the headwaters and middle reaches. Twenty-two species were present, with the greatest species richness occurring in an unregulated segment upstream of the middle reach dams; average nymphal biomass over the study period (175 organisms, 395 mg dry mass m^?2) was also greatest in this segment. Only four species (58 organisms, 48 mg m^?2) were present in the tailwaters of the headwater dam and values were greatly reduced (nine species; 35 organisms, 180 mg m^?2) below the middle reach dams. The stonefly community recovered ca. 80 km downstream from the last dam (15 species; 244 organisms, 250 mg m^?2), apparently in response to natural resetting of environmental conditions corresponding to those above the middle reach dams. At the most downstream site (11) only four species (four organisms, 16 mg m^?2) were present. The observed distributional pattern is a classic serial discontinuity in response to hypolimnial stream regulation in a temperate latitude river.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.