地下水人工回灌试验研究

北京市是我国以地下水为主要供水水源的大城市之一。本区属于干旱、半干旱气候区,多年平均降雨量为635毫米,丰水年份雨量最大可达1000毫米以上,枯水年份小于400毫米,多集中在七、八月份。雨量差异很大,分配极不均匀。雨量的多寡直接控制着北京地下水的丰富程度,遇到干旱年份城市供水就很紧张。从长远看,必须采取积极措施。我们分析了国内     

洛阳市浅层地温能开发利用现场回灌试验研究

浅层地温能作为一种清洁的,可再生的能源,是国家要求大力探索和发展的新能源,其开发利用在全国呈现出如火如荼的态势。河南洛阳因其厚层第四系及丰富的浅层地下水资源在水源热泵利用方面具有得天独厚的优势。根据在不同地质地貌单元进行的现场抽回灌试验,初步确定不同地区的抽灌井比例及井距,为城市浅层地温能开发利用提供依据。     

浅层地下水人工回灌应用于上海市工程性地面沉降防治的试验研究

上海地面沉降主要由过量开采地下水资源和大规模工程建设等因素共同影响,工程性地面沉降引起的地面沉降漏斗严重影响了周边地区生命线工程的建设及运营安全。通过开展试验研究,将深部承压含水层中应用成熟的地下水人工回灌技术引入浅部含水层中,但由于浅部含水层砂层结构及水动力条件与深部含水层差异较大,回灌工艺及方法也存在差异。本次试验工作中,改进了地下水人工回灌工艺流程,并通过同步地面形变监测分析了浅层地下水人工回灌对控制地面沉降的作用效果。结合上海地区实际地层特征以及各种回灌工艺的实际效果,评价了浅层地下水人工回灌技术在防治工程型地面沉降中推广应用的可行性及适用性。     

北京西郊地下水人工回灌试验研究

地下水人工回灌是建立地下水库的“联通器”,是水资源人工调蓄必不可少的手段。三年来,我们按不同水文地质单元,因地制宜,结合生产急需布置了多种形式的回灌试验点36个:有旧河道的、有平原水库的、有深井和大口井的,有砂石坑的。     

地下水人工回灌气相堵塞特征的试验研究

地下水人工回灌可以高效地利用雨季丰沛的水量来缓解地下水过量开采造成的海水入侵、泉水断流等环境水文地质问题,但回灌堵塞一直是制约人工回灌效率的关键问题。针对雨洪水回灌携带的大量气泡问题,设计室内砂柱试验模拟装置,利用曝气水进行人工回灌,定时记录试验过程中测压管读数及出流流量,利用达西定律计算各层渗透系数,研究气相堵塞的发展过程和规律。结果表明:回灌过程中由于气相堵塞导致含水层渗透系数随时间呈指数衰减,气相堵塞主要发生在介质浅表层（0~30 cm）,且随时间有向下发展的趋势,堵塞速率随深度的增加逐渐减小,在回灌过程中适时停灌进行排气有利于减小气相堵塞对回灌效率的影响。     

地下水人工回灌含水介质微生物堵塞试验研究

地下水人工回灌过程中,含水介质的堵塞除机械颗粒沉积和化学沉淀外,微生物起重要的作用。然而,目前探究回灌堵塞过程中以生物量为主要研究内容反映生物堵塞的发生,对其堵塞发生过程中微生物菌群组成结构的研究较少。采用室内一维渗流试验,开展含水介质微生物堵塞过程研究。分析含水介质渗透性、营养盐指标及胞外聚合物含量时空动态变化,利用16SrRNA高通量测序技术,深入分析微生物群落多样性和结构特征,从分子水平上揭示含水介质回灌堵塞过程中微生物群落特征及其演替规律。研究结果表明,随着回灌持续,含水介质渗透性呈现非线性降低趋势;空间上,堵塞主要发生在介质表层;时间上,各层介质渗透性依次经历稳定波动—快速下降—缓慢下降—趋于稳定4个阶段。含水介质附着细菌主要分布于26个门,65个纲,162个目,258个科,425个属,767个种。随着回灌的进行,细菌群落丰度、多样性及均匀度均呈现降低趋势。含水介质上附着细菌群落结构发生明显演替。菌群以变形菌门为优势菌门,拟杆菌门为次优势菌门;假单胞菌属(Pseudomonas)为主要优势菌属。     

廊坊地区浅层地热能开发前景及地下水回灌试验研究

本文在对廊坊市万庄镇的浅层地热资源量进行概算的基础上,对水源热泵在该区的推广可行性做了评价;并且通过野外场地试验,对该区地下水供给能力及回灌能力进行了研究.得出如下主要结论:(1)该区域浅层地热能储量丰富,总储量约为18075.0×10KJ,相当于标准煤616.8×104t,具备推广水源热泵的基础条件.(2)研究区浅层含水层富水性较好,水质较好、供水能力较强,满足水源热泵的运行,也利于地下水回灌,不引起水资源的浪费.(3)在不引起次生环境地质问题前提下,建议在水源热泵系统运行时单井抽水量控制在80m3/h左右,单井回灌量不超过40m3/h,采用一抽两灌的原则配置抽、灌井数量,抽水井和回灌井的井间距控制在70~80 m,这样能够使得被抽取的地下水基本得到回灌补给,也可合理的利用浅层地热资源.     

西安市的地下水人工回灌

面对西安市城市甩水供需矛盾日益突出的严重局面,本文提出在注重修建引水工程的同时,应大力开展人工回灌,以保证现有的供水能力和缓解地下水严重超采而引起的环境问题。     

太原市地下水人工回灌的初步分析

针对太原市地下水开发利用所引起的严重问题,文中提出用人工回灌解决这一问题的设想.并指出汾河泾流和汾河水库汛期弃水有1.77亿m~3,另有兰村以下的各支流洪水、及城市污水和雨水,都可作为回灌水源;作为回灌库址,西山古交区、兰村至三给地垒、三给地垒至小店约有9.12亿m~3的库容。通过拦河闸坝和打回灌孔,便可解决地下水的回灌问题.文中还对回灌涉及到的煤矿突水、水质、下游供水、河道堵塞,含水层泥沙淤积等问题,提出了见解和措施.     

北京地区地下水人工回灌简介

北京地区开展人工回灌有了近50年的历史,经历了试验和工程实施阶段。试验阶段包括深井、砂石坑、大口井回灌等试验,工程实施包括城市雨洪利用和再生水回灌利用等。     

基于地中渗透仪的入渗补给方式分析

文章通过在某均衡试验场地中的渗透仪上开展土壤水流穿透试验,分析灌溉水对地下水补给方式。试验结果表明:淹灌条件下,粉细砂扰动土中的穿透曲线为典型的单峰对称型,表明粉细砂中的土壤水通过活塞式入渗补给地下水;而亚粘土中的穿透曲线显示多峰、优先穿透、拖尾等现象,表明亚粘土中的土壤水以优势流方式补给地下水。通过对均衡场降水入渗补给的长观资料分析发现:在自然降雨条件下亚粘土中优势流明显,粉细砂中主要以活塞流为主。     

基于GIS的地下水水源地补给潜力探讨

本文提出了一种基于GIS的补给潜力分析方法.在实例研究中,通过对地形、地表物质组成、包气带岩性、植被覆盖等因子建立的专题图层的叠加分析,确定了地下水的补给潜力分区,结合研究区含水层分布特征,综合确定了水源地的靶区和开采潜力区.研究表明,利用GIS确定研究区降雨入渗补给量是一种高效、直观、可行的方法.     

基于浅层地下水回灌的基坑工程沉降防治分析与计算

采用下负荷面剑桥模型,联合渗流方程,建立土-水完全耦合平衡方程计算模型,探讨浅层地下水人工回灌在基坑工程降水过程中抑制基坑周边地面沉降的作用,并以邻近上海地铁一号线的淮海中路3号地块基坑降水为例,对基坑工程实测沉降和回弹数据进行数值拟合,理论结果与实际数据吻合。本方法对基坑工程地下水回灌防止地面沉降有一定参考指导作用。     

The impact of intensive groundwater abstraction on recharge to a shallow regional aquifer system: evidence from Bangladesh

Quantitative evaluations of the impact of groundwater abstraction on recharge are rare. Over a period (1975??007) during which groundwater abstraction increased dramatically in the Bengal Basin, changes in net groundwater recharge in Bangladesh are assessed using the water-table fluctuation method. Mean annual groundwater recharge is shown to be higher (300??00?mm) in northwestern and southwestern areas of Bangladesh than in southeastern and northeastern regions (<100?mm) where rainfall and potential recharge are greater. Net recharge in many parts of Bangladesh has increased substantially (5??5?mm/year between 1985 and 2007) in response to increased groundwater abstraction for irrigation and urban water supplies. In contrast, net recharge has slightly decreased (??.5 to ???mm/year) in areas where groundwater-fed irrigation is low (<30% of total irrigation) and where abstraction has either decreased or remained unchanged over the period of 1985??007. The spatio-temporal dynamics of recharge in Bangladesh illustrate the fundamental flaw in definitions of “safe yield??based on recharge estimated under static (non-pumping) conditions and reveal the areas where (1) further groundwater abstraction may increase actual recharge to the shallow aquifer, and (2) current groundwater abstraction for irrigation and urban water supplies is unsustainable.     

Review: Current and emerging methods for catchment-scale modelling of recharge and evapotranspiration from shallow groundwater

A review is provided of the current and emerging methods for modelling catchment-scale recharge and evapotranspiration (ET) in shallow groundwater systems. With increasing availability of data, such as remotely sensed reflectance and land-surface temperature data, it is now possible to model groundwater recharge and ET with more physically realistic complexity and greater levels of confidence. The conceptual representation of recharge and ET in groundwater models is critical in areas with shallow groundwater. The depth dependence of recharge and vegetation water-use feedback requires additional calibration to fluxes as well as heads. Explicit definition of gross recharge vs. net recharge, and groundwater ET vs. unsaturated zone ET, in preparing model inputs and reporting model results is necessary to avoid double accounting in the water balance. Methods for modelling recharge and ET include (1) use of simple surface boundary conditions for groundwater flow models, (2) coupling saturated groundwater models with one-dimensional unsaturated-zone models, and (3) more complex fully-coupled surface-unsaturated-saturated conceptualisations. Model emulation provides a means for including complex model behaviours with lower computational effort. A precise ET surface input is essential for accurate model outputs, and the model conceptualisation depends on the spatial and temporal scales under investigation. Using remote sensing information for recharge and ET inputs in model calibration or in model–data fusion is an area for future research development. Improved use of uncertainty analysis to provide probability bounds for groundwater model outputs, understanding model sensitivity and parameter dependence, and guidance for further field-data acquisition are also areas for future research.     

The influence of model structure on groundwater recharge rates in climate-change impact studies

Numerous modeling approaches are available to provide insight into the relationship between climate change and groundwater recharge. However, several aspects of how hydrological model choice and structure affect recharge predictions have not been fully explored, unlike the well-established variability of climate model chains—combination of global climate models (GCM) and regional climate models (RCM). Furthermore, the influence on predictions related to subsoil parameterization and the variability of observation data employed during calibration remain unclear. This paper compares and quantifies these different sources of uncertainty in a systematic way. The described numerical experiment is based on a heterogeneous two-dimensional reference model. Four simpler models were calibrated against the output of the reference model, and recharge predictions of both reference and simpler models were compared to evaluate the effect of model structure on climate-change impact studies. The results highlight that model simplification leads to different recharge rates under climate change, especially under extreme conditions, although the different models performed similarly under historical climate conditions. Extreme weather conditions lead to model bias in the predictions and therefore must be considered. Consequently, the chosen calibration strategy is important and, if possible, the calibration data set should include climatic extremes in order to minimise model bias introduced by the calibration. The results strongly suggest that ensembles of climate projections should be coupled with ensembles of hydrogeological models to produce credible predictions of future recharge and with the associated uncertainties.     

Spatial and temporal variation of groundwater recharge in shallow aquifer in the Thepkasattri of Phuket,Thailand

Whether groundwater resources can be sustainably utilized is largely determined and characterized by hydrogeological parameters.Estimating the groundwater recharge is one of the essential parameters for managing water resources and protecting water resources from contamination.This study researched the spatial and temporal variation of groundwater recharge in the Thepkasattri sub-district through integrating chloride mass balance(CMB)and water table fluctuation(WTF)methods.The chloride content of representative rainfall and groundwater samples was analyzed.Besides,WTF method was adopted from groundwater level data from 2012 to 2015.According to the CMB method,the mean recharge was estimated to be 1172 mm per year,accounting for 47%of the annual rainfall.Moreover,the estimated recharge from the WTF method took 26%of annual rainfall in 2015.The recharge was underestimated according to the WTF method,because of the uncertainty in specific yield estimates and the number of representative wells in the study area.Moreover,the correlation between rainfall and water table fluctuation data indicated the positive linear relationship between two parameters.The spatial recharge prediction indicated that recharge was higher(1200-1400 mm/yr)in the eastern and western catchment,while that in the central floodplains was between 800 mm/yr and 1100 mm/yr.In addition,low recharge value between 450 mm/yr and 800 mm/yr was observed in the south-west part of Thepkasattri.The spatial variation of recharge partly reflects the influences of land use and land cover of the study area.     

不同降水及灌溉条件下的地下水入渗补给规律

天然降水和人工灌溉是华北平原浅层地下水的主要补给来源。长期过量开采地下水导致华北平原地下水位持续下降,详细分析降水变化规律及灌溉制度的影响有利于深入认识补给及正确评价入渗补给量,对合理开发利用地下水资源具有重要意义。基于实测资料,用HYDRUS软件建立一维变饱和流数值模拟模型,模拟分析了衡水地区近60年在天然降水条件下的垂向入渗补给规律,以及在年周期内灌溉活动对于入渗补给规律的影响。结果表明:研究区多年平均降水入渗补给量为66.6 mm/a;枯水年份降水入渗补给量为30 mm/a,丰水年入渗补给量为120~150 mm/a;年补给量与年降水量具有显著的正相关性;入渗补给系数与降水强度呈负相关关系;入渗补给量随灌溉量的增加而增加,实验条件下小麦底墒水与玉米灌溉对应入渗补给系数较大,实际灌溉中应基于当年降水情况及土壤墒情确定合理的灌水定额。     

基于小波分析的趵突泉地下水补给范围探讨

为查明济南趵突泉地下水补给范围以及市区、西郊对趵突泉的补给范围所占比例,选取2010—2020年趵突泉泉域20个地下水长期监测点的岩溶水位数据,采用交叉小波变换的方法对地下水位与降水量的时滞进行分析,并结合泉水的功能分区对趵突泉地下水补给范围进行探讨,计算市区、西郊对趵突泉的补给范围所占比例。结果表明：（1）随着地下水径流长度的增加,地下水位对降水时滞呈现增大的趋势,从78.58 d增大至129.22 d,济南西郊的时滞变化梯度大于济南市区;（2）玉符河下游地下水补给范围大,径流路径长,河流沿线地下水位对降水量的时滞大于两侧;刘长山−郎茂山−万灵山一带地下水径流路径较短,岩溶富水性较差,地下水位对降水量的时滞小于两侧;济南市区与西郊地下水存在水力联系;（3）选取趵突泉水位与降水量的时滞等值线为趵突泉补给范围的北边界,东边界为东坞断裂,西边界为马山断裂,南边界为地表分水岭,趵突泉的补给范围为1 390.54 km²。（4）济南西郊对趵突泉的补给范围为1 133.09 km²,市区对趵突泉的补给范围为257.45 km²,西郊和市区对趵突泉的补给范围面积比值为4.4∶1。