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1.
以安阳市平原区为例,根据水均衡原理,利用当年汛期末浅层地下水位埋深和汛期降雨量以及汛期前地下水补给量等信息,建立安阳市平原区基于数值模拟模型的枯季地下水可开采量(可供水量)实时预报模型。研究结果可为区域地下水水源评估提供参考。  相似文献   

2.
邯郸东部平原工农业用水主要靠开采浅层地下水,而地下水补给量又主要靠降雨入渗补给形成,进入80年代以来,工农业用水量日益增加,地下水超采严重,引起地下水水位大幅度下降。根据上述现象,本文通过对邯郸市东部平原区地下水观测资料分析,建立(P_年~_浅~H_末)相关的简易模型,用于解决确定合理的地下水开采量及其预测等问题。  相似文献   

3.
暴雨洪水对地下水超采缓解特征与资源增量   总被引:3,自引:1,他引:2  
针对暴雨洪水对超采区浅层地下水位不断下降趋势的缓解作用问题,以海河南系平原"96.8"暴雨洪水为例,采用时间序列异变特征和趋势分析方法,基于该区逐月地下水位动态长观资料和降水资料,通过对暴雨洪水主要区域的浅层地下水位急剧变化特征和不同时段变化趋势研究,结果表明:(1)类似"96.8"的暴雨洪水对减缓海河南系平原区浅层地下水的区域性超采趋势具有显著作用,暴雨洪水的充分补给是该平原区地下水均衡不可缺少的补给模式,"96.8"暴雨洪水对地下水资源的补给增量达每百平方公里0.69亿~1.07亿m3;(2)暴雨洪水补给地下水过程主要发生在冲洪积平原区的河道带与汇水洼地等强入渗区域,呈线状、斑块状选择性补给分布特征,具有客观的自然属性;(3)近30年以来海河南系平原区浅层地下水位不断下降,与该区地下水补给水源和补给量不断减少有一定关系。因此,保障暴雨洪水对平原区地下水系统合理补给应是有效缓解区域地下水超采状况的重要方面。  相似文献   

4.
20 0 2年 8月 ,受强热带风暴“北冕”和弱冷空气共同影响 ,北江上游主要支流武水发生了一场特大暴雨洪水 (以下简称“0 2·8”暴雨洪水 ) ,乐昌水位站出现了 91.0 5m的历史最高洪峰水位 ,比历史最高洪峰水位 (“94·6”的 90 .2 5m)高了 0 .80m。“0 2·8”暴雨总历时 7d ,流域平均降雨量 2 5 0 .6mm。流域内的造峰雨时间主要集中在 5~ 7日 3d ,降雨在空间分布上不均匀。 4~ 5日 ,墩子站有大到暴雨 ,其余站个别有中雨 ,大部分地方降雨很小。 5~ 6日 ,中游的两江口站和墩子站一带降了大暴雨 ,其中日雨量较大的是两江口站的 14 6 .0mm、墩…  相似文献   

5.
2016年7月19日安阳遭遇了罕见的特大暴雨,林州百石湾雨量站24 h降雨量达738 mm,多地雨量站24 h最大降雨量超过300 a一遇,安阳水文站出现了1950年以来有实测资料的第二大洪水。通过对安阳市67眼地下水监测井的埋深动态资料分析,"7·19"暴雨洪水后安阳地区地下水埋深抬升明显,安阳平原区地下水总蓄变量为1.51亿m3,这次降水过程对安阳市地下水的补给非常显著。  相似文献   

6.
淮北平原区降雨入渗补给量的研究   总被引:1,自引:1,他引:0  
本文从淮北平砂区降雨入涌的物理过程出发,分析了不同降雨资料系列,不同开发利用水平下,利用试验研究方法,探讨了该地区不同降雨年型的降雨入渗补给量和系数的变化趋势。并运用地下水多年逐旬调节计算模型对该区在限制水位开采埋深情况下充分开采浅层地下水时入渗补给量作了预测计算 。  相似文献   

7.
准确计算降雨入渗补给量是评价平原区地下水资源量的基础,传统的年补给系数法未考虑降雨特征、土壤墒情等因素影响,导致评价结果精度不高。本研究以河北平原下博和沧县运西两个典型小流域为例,采用动态分析法研究次降雨的入渗补给过程。结果显示以7 d为时间间隔适合作为划分次降雨的标准,次降雨量加土壤含水量(P+SW)与降雨入渗补给量(Pr)相关性最好,优于次降雨量(P)和次降雨量加前期雨量(P+Pa);动态分析法计算的降雨入渗补给量较传统降雨入渗系数法,精度提高22%~40%,且年补给系数法高估了河北平原区的年地下水补给量。本研究为河北中东部平原准确评价降雨入渗补给量提供了技术参考,对支撑区域的地下水合理开发利用及地下水超采综合治理具有较强的科学和实践意义。  相似文献   

8.
李燕红 《人民黄河》2007,29(11):25-26
对雨洪法计算设计洪水的适用面积进行了分析,认为:影响雨洪法适用面积的主要因素是设计暴雨形成的产流面积;检验设计暴雨是否能形成全面产流是能否使用雨洪法的唯一标准。常遇洪水的计算,必须在设计暴雨确定后以产流面积进行检验。根据山西省控制流域面积在1000 km2以下的水文站、形成全面产流的600余站次洪水最小面平均降雨量资料,绘制了饱和与非饱和2种产流方式的全面产流检验曲线,可供相关地区采用雨洪法计算设计洪水时参考。  相似文献   

9.
一、2016年防汛抗旱工作取得全面胜利 2016年,我省平均降雨量784毫米,较多年均值偏多1成多.汛期出现了9次较大降雨过程,其中3次特大暴雨过程,信阳、新乡、安阳等地先后发生较大洪涝灾害.去年的雨情、水情和灾情呈现出以下三个特点:一是降雨强度大,局地超极值.6月30日至7月1日,暴雨中心位于信阳市淮南山区,累计最大点雨量360毫米,24小时降雨量超过50年一遇;7月8日至10日,暴雨中心位于新乡市,降雨量频率超100年一遇,累计最大点雨量461毫米,超历史极值;7月18日至21日,暴雨中心位于安阳市林州、安阳一带,累计最大点雨量达738毫米,降雨量频率达到1000年一遇.二是洪水过程强,河库压力大.受强降雨影响,淮干及部分支流先后出现5次洪水过程,共产主义渠、卫河出现2次洪水过程.淮河干流王家坝、支流潢河、竹竿河出现超警洪水过程,卫河支流安阳河安阳水文站出现超保证洪水;南海、彰武水库水位超历史最高水位,双泉水库水位超设计水位2.26米.三是灾害区域广,局部损失重.全省汛期因洪涝受灾人口220.2万人,死亡28人,失踪9人,农作物受灾面积146.8千公顷,安阳河发生3处堤防溃口险情,崔家桥滞洪区自然进洪运用,广润坡滞洪区内涝严重,南水北调排水工程出现4次险情,京九铁路新县段中断1次.新乡、安阳、鹤壁市城区及辉县市、原阳县县城发生严重内涝,部分村庄进水.灾害造成直接经济损失约106.3亿元.  相似文献   

10.
为了及时准确评估安阳市洪水灾害风险,构建了安阳市洪水灾害风险评价指标体系及安阳市洪水灾害风险等级云模型。同时,利用熵权法和模糊变换法得到安阳市各县区的洪水灾害风险等级评价表,并绘制出安阳市洪水灾害风险评价地区分布图。以安阳市"7·19"特大暴雨进行验证,检验了指标选取的合理性及结果的准确性。研究结果表明:林州市和安阳县存在高风险洪水灾害等级,因为两地依靠太行山脉,受地形地势影响,降雨尤其集中,洪水灾害发生的可能性极高;且两地人口密度较高,洪水灾害容易造成较大的损失。  相似文献   

11.
Call for Papers     
正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.  相似文献   

12.
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。  相似文献   

13.
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.  相似文献   

14.
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。  相似文献   

15.
The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L?1, the median total phosphorus was 0.29 mg L?1 and the median total nitrogen was 1.56 mg L?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.  相似文献   

16.
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).  相似文献   

17.
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.  相似文献   

18.
Carbon dioxide (CO2) and methane (CH4) diffusive emissions were measured during two field surveys in Queensland and Tasmania, Australia, using the floating chamber method. Bubbling and degassing emissions in 2010 were estimated in Koombooloomba Dam reservoir using only inverted funnels and gas concentrations, respectively. A total of 14 reservoirs and 16 rivers and lakes were sampled from 2006 to 2010. Spatial variation was substantial within each water body, as well as between them. The main drivers of diffusive emission variation were physiographic region and climate, with a clear demarcation being observed between diffusive emissions from tropical Queensland and temperate Tasmania, and between the humid West Coast Range (Tasmania) and dry Central Plateau (Tasmania). Higher CO2 and CH4 diffusive emissions were observed during the dry season, when long water residence times would promote organic matter degradation. Estimated total gross emissions, including diffusive, bubbling and degassing emissions, for Koombooloomba Dam reservoir were about 1.5 × 106 t CO2eq km2 per year, or 24 × 106 t CO2eq per year. This corresponds to a plant emission factor of 3.18 kg CO2eq MWh?1. Using an estimate of terrestrial emissions derived from literature data for the Tully River catchment area, rough estimated net emissions from the catchment area are about 44 kt CO2eq per year, or 5.83 kg CO2eq MWh?1, which is in the lower range of the studied reservoirs.  相似文献   

19.
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。  相似文献   

20.
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.  相似文献   

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