Using environmental isotopes to evaluate the renewable capacity of a typical karst groundwater system in northern China

The karst groundwater in northern China is an important source of water supply. Its capacity for self-renewal is a key factor affecting its sustainable use. The Pingyi–Feixian karst aquifer in central and southern Shandong Province is a typical karst water source, contributing 54% to the total groundwater taken from the region. In this study, 25 groups of water samples were collected from the Pingyi–Feixian karst aquifer in November 2013. The compositions of isotopes of tritium (³H), carbon-13 (¹³C), and carbon-14 (¹⁴C) were measured. As indicated by the tritium values between 7.1 and 12.2 TU, the Pingyi–Feixian karst groundwater is primarily originated from both historical atmospheric precipitation and modern precipitation. The ¹⁴C ages corrected by δ¹³C were between 146 and 5403 years. Specifically, the shallow groundwater is younger than deep groundwater. Groundwater age tends to increase along the flow path. The ages of the groundwater in recharge area were between 146 and 1348 years, while the ages of deep groundwater in flowing area were generally between 2000 and 4000 years. The ages of the groundwater in discharge area with little anthropic exploitation were larger than 4500 years, whereas these with large amounts of exploitation were less than 1500 years. The shallower the groundwater, the stronger its capacity for renewal. The renewable capacity of karst groundwater in discharge area was significantly affected by anthropic exploitation. The karst groundwater in the areas with less exploitation showed the weakest capacity, whereas that in the area with intensive exploitation was much older and had a stronger renewable capacity.     

丰沛平原区地下水开采利用现状及潜在水源地分析

通过总结丰沛平原区水文地质条件和特征,对该区地下水开采利用现状及潜在水源地进行分析,计算了华栖隆起区岩溶水可利用资源量,探讨裂隙岩溶水利用的可行性。研究表明: 丰沛平原区地下水主采层位为中上更新统孔隙含水层和新近系—下更新统孔隙含水层,已形成丰县城关—孙楼—常店和沛县—龙固2个大型超采漏斗区,总面积超过750 km²,引发了大面积地面沉降; 华栖隆起区为裂隙岩溶水的富水地段,总可采资源量为667.51万m³/a,可作为潜在水源地进一步开展地下水勘查评价工作; 裂隙岩溶水过量开采可能引发地面沉降、岩溶地面塌陷等地质灾害,后期应对裂隙岩溶水开采情况进行长期监测,合理开发利用水资源。华栖隆起区岩溶水距离城区近,水量大,水质好,开发难度小,具有可观的经济价值。     

海河流域地下水资源特征和开发利用潜力

海河流域水资源严重短缺,地下水长期超采是制约社会经济可持续发展的主要瓶颈。开展流域地下水资源及开发利用潜力研究,对支撑服务地下水超采治理、地下水资源可持续利用和生态环境保护都具有重要意义。经系统评价,海河流域天然资源量252.99×10~8m~3,生态水位约束条件下的浅层地下水开采资源量172.98×10~8m~3,可更新的深层水可利用量4.68×10~8m~3。海河流域山区地下水质量总体较好,Ⅰ～Ⅲ类水占比40.83%,平原区浅层地下水质量较差,Ⅰ～Ⅲ类水占比14.10%,深层地下水质量优于浅层地下水,Ⅰ～Ⅳ类水占比74.25%。海河流域山区地下水开采潜力总体较小,燕山和太行山北部山区,地下水资源禀赋较差,基本无开采潜力,太行中部山区地下水开采程度较高,无开采潜力或开采潜力较小,太行南部山区地下水资源禀赋良好,开采潜力较大;平原区浅层地下水在不同水文地质单元开采潜力差异较大,山前平原浅层地下水长期超采形成大范围降落漏斗,无开采潜力或潜力较小,中东部平原浅层地下水资源禀赋较差,以微咸水为主,开采潜力较小,山东省鲁北平原区浅层地下水开采程度较低,聊城—德州一带开采潜力较大;雄安新区地下水总体无开采潜力。平原区深层地下水基本无开采潜力。     

丰沛平原区地下水开采利用现状及潜在水源地分析

通过总结丰沛平原区水文地质条件和特征,对该区地下水开采利用现状及潜在水源地进行分析,计算了华栖隆起区岩溶水可利用资源量,探讨裂隙岩溶水利用的可行性。研究表明: 丰沛平原区地下水主采层位为中上更新统孔隙含水层和新近系—下更新统孔隙含水层,已形成丰县城关—孙楼—常店和沛县—龙固2个大型超采漏斗区,总面积超过750 km²,引发了大面积地面沉降; 华栖隆起区为裂隙岩溶水的富水地段,总可采资源量为667.51万m³/a,可作为潜在水源地进一步开展地下水勘查评价工作; 裂隙岩溶水过量开采可能引发地面沉降、岩溶地面塌陷等地质灾害,后期应对裂隙岩溶水开采情况进行长期监测,合理开发利用水资源。华栖隆起区岩溶水距离城区近,水量大,水质好,开发难度小,具有可观的经济价值。     

基于禀赋差异性的地下水资源可持续开发利用评价——以德阳市为例

德阳市是西南地区的缺水城市,不同区域地下水资源禀赋特征差异明显,为分析地下水资源开发利用的可持续问题,按照地下水资源禀赋的差异性构建了地下水资源可持续开发利用评价指标体系,选取了3个代表性区域进行分区评价研究,并根据研究区地下水的主导功能确定了评价结果内涵。研究结果表明:构建的评价指标体系及评价结果能够反应不同分区影响地下水可持续开发利用的关键性指标和地下水资源禀赋的差异性。研究成果有助于提高对四川盆地内的地下水功能区和地下水资源禀赋特征的认识,可为研究其可持续开发利用问题提供借鉴。     

西南岩溶山区地下水资源承载能力评价——以贵州省七星关区为例

以国家扶贫攻坚重点地区——贵州乌蒙山七星关区为例,参考"全国地质资源环境承载能力评价与监测预警"形成的评价理论和方法,结合岩溶石山区地下水资源水文地质条件及开发利用实际,探索构建岩溶石山区县域范围内地下水资源承载能力评价方法。通过系统评价七星关区地下水资源承载能力,认为该区地下水资源承载能力较大,但资源、开采强度、劣质水分布不均,降低了部分区域地下水资源承载能力。评价结果为区域国土空间规划及"三区三线"划定提供了依据。同时,该评价方法亦为岩溶地区地下水资源承载能力评价提供了借鉴。     

Numerical simulation and environmental impact prediction of karst groundwater in Sangu Spring Basin,China

The changes of development and utilization of karst groundwater in Sangu Spring Basin have made the original groundwater resource evaluation unable to meet the needs of future economic development. Based on analysis of existing data, combined with the characteristics of supplement, runoff and draining of regional karst groundwater, the Visual Modelflow software was used to build a numerical simulation model of Sangu spring Basin. The amount of karst groundwater resource and groundwater environment of the Basin were evaluated under different exploitation schemes, and the changes of karst groundwater environment in the future ten years were also predicted. The fitting error which is less than 0.5 m between the calculated value and measured value of the water level in the fitted borehole accounts for 93%. For the lithologically and structurally complex Sangu Spring Basin, the fitting effect of numerical simulation model was ideal. On the basis of the current mining amount of 111.80 million m³/a, the total redistributed exploited amount in the spring region was 61.79 million m³/a. Under the condition that the quantity of recoverable resources reached 173.59 million m³/a and under different precipitation schemes, all constraint conditions were satisfied, such as regional water level drawdown, maximum allowable water level drawdown in every simulated water source area and the flow rate of Guobi Spring. The results will provide a scientific basis for the rational development and utilization of karst groundwater in Sangu Spring Basin.     

山东淄博沣水泉域岩溶水系统模拟及水源地优化开采预测

沣水泉域岩溶水系统是淄博市及周边地区最主要的供水水源,因原有大武水源地水质严重污染,急需开辟新的水源地,故须重新开展泉域岩溶水资源评价和开采规划工作。文章在充分概化研究区水文地质概念模型的基础上,借助FeFlow软件,建立了基于等效连续介质的三维非均质各向异性岩溶水模型,并利用2016年水位动态数据对模型进行识别和验证。经模型计算可知,在2000-2015年,研究区岩溶地下水日均补给量为104.47万m3/d,排泄量为80.27万m3/d,正均衡24.20万m3/d。对原大武水源地与新增刘征水源地优化开采方案预测的结果表明,最优开采方案为:（1）保持大武水源地现状35.91万m3/d开采条件下,刘征水源地最大开采量为5.5万m3/d,刘征 -大武富水地段最大可开采量为41.41万m3/d;（2）满足刘征 -大武富水地段最大开采条件,大武水源地最大可减采至33.41万m3/d,刘征最大开采量为8万m3/d。      

两城水源地喀斯特水资源评价

两城水源地具有较丰富的喀斯特水，根据长期观测资料，充分考虑水资源的各种补给和开采条件，应用水均衡原理，对其水资源量进行定量评价，获得允许可开采量，为工农业供水提供可靠依据。     

Feasibility Analysis on Resuming Flow of Large Karst Spring in Heilongdong

Based on discussion about the features of karst groundwater resources distribution of karst water system in Heilongdong Springs and causes of spring groups cutoff and according to current karst groundwater resources and exploitation distribution conditions of coal resources, this paper put forward the measures for protecting groundwater resources, i.e. intensifying plugging of underground coal mine gushing water points, grouting in advance to reinforce the small faults and weak lower confining bed of coal seam and leave sufficient waterproof coal pillars based on adjustment of the water sources for centralized water supply and water supplying and draining and countermeasures of improving use ratio of mine water and replacement of direct exploitation to realize resuming flow of spring groups and sustainable development of groundwater resources and exploitation of coal resources     

Water-management failure under complex hydrogeological conditions in the Kolubara District, Serbia

The design of the Rovni Lake reservoir in the Kolubara District, western Serbia, is the basis for the regional water-supply system there. The design was promoted as an example of integrative and sustainable water management, with regard to the planned provision for long-term municipal water supply in the Kolubara region, as well as for the regulation of the downstream river flow. Hydrogeological analyses, however, have indicated three key issues that contest this sustainable water-management model: (1) the capability of the available groundwater sources to fully meet the drinking water demands in the region, (2) a pronounced risk of water loss from the reservoir, and (3) a pronounced risk of karst aquifer contamination. The Rovni project ignores the hydrogeological properties of a karst aquifer and thereby needlessly threatens the groundwater resource. Hence, modifications to the project are recommended in order to mitigate or eliminate the most significant construction and ecological risk factors and to improve sustainable exploitation and integrative water-resource management.     

陇东盆地西部岩溶地下水形成机制研究

陇东盆地西部处于鄂尔多斯盆地西缘逆冲推覆构造带，新元古-下古生界碳酸盐岩裸露或浅埋，构成-南北向展布的岩溶水富集带。通过运用构造控水分析、水化学同位素等方法，对岩溶裂隙水系统进行了深入的分析与讨论。指出本区岩溶水的空间分布明显受南北向逆冲推覆构造控制，储水空间以岩溶裂隙为主，构造条件是岩溶发育和岩溶水富集的主要制约因素。岩溶水化学特征具有明显的南北差异，在补给条件优越的中南部平凉-华亭地区，水化学主要由含水层岩性及其赋存条件决定。岩溶地下水以大气降水来源为主，对于埋藏型岩溶水表现为多源水混合而成。根据岩溶水的空间分布与水动力场特征及其补径排条件，全区可划分为平凉、华亭和环西3个相对独立的岩溶水系统．并以此可作为水资源评价的基础。这些认识对于深入了解西北干旱-半干旱地区岩溶水赋存及富集规律、形成与演化机理和在该区开发利用岩溶地下水资源具有重要的科学意义。     

大兴迭隆起隐伏岩溶水资源评价及开采方案预测

大兴迭隆起地区隐伏岩溶地下水是北京市的重要水源,为保障水源地能持续为大兴、通州地区提供优质的城镇生活用水,需对研究区岩溶地下水进行水资源评价和开采规划预测分析。利用数值模拟法,应用GMS模拟软件对研究区岩溶水系统进行地下水流数值模拟及水位变化预测。建立的岩溶水系统模型分为5层,模拟验证期为12年9个月。由模型评价的岩溶水系统补给资源量为14 425.74×10^4m3/a,可开采资源量为14 310.52×10^4m3/a,其中岩溶含水层可开采量为2 309.36×10^4m3/a。在模型识别验证后,分4种开采方案对水源地进行开采预测,通过对典型观测孔水位过程线拟合和研究区水均衡分析可知,按2020年之前维持现状开采,2020年后停采念坛水源地,2025年后全区按可开采量进行开采的开采方案最为合理,可分批逐次实现水源地的采补平衡。     

Sustainable yield of a karst aquifer system: a case study of Jinan springs in northern China

Based on the long-term monitoring data of rainfall, groundwater levels, groundwater abstraction, spring flow rates and groundwater quality, an assessment has been undertaken of the sustainable yield of a karst aquifer system in Shandong Province, northern China, to maintain perennial outflow of the karst springs while meeting water demands. One of the fundamental indicators for sustainable yield of groundwater is identified as maximum allowable water-level drawdown. A regional three-dimensional finite-difference numerical model has been developed to optimize the schemes associated with well fields and their locations and sustainable yields, in the Jinan spring catchment and its adjacent karst groundwater catchments, with the aim of maintaining the water level higher than the allowable lowest water level of 27.5?m above sea level. Furthermore, measures necessary to move towards sustainable use of the karst groundwater are outlined, drawing on contingency plans of water-source replacement and artificial recharge, dual water supply (based in water quality), use of the spring waters themselves, and groundwater quality protection.     

Karst groundwater management by defining protection zones based on regional geological structures and groundwater flow fields

In a semiarid region, the karst aquifer generally forms a large groundwater reservoir that can play an important role in regional water supply. But because of the specific physical properties of karst aquifers, they are vulnerable to pollution and anthropogenic impacts. Karst groundwater management strategies are vital. As representative of karst springs in a semiarid area, Niangziguan Springs is located in the east of Shanxi Province, China with an annual average rate of discharge of 10.34 m³/s (1956–2003) (Y. Liang, unpublished data). The Niangziguan Spring Basin covers an area of 7,394 km² with an annual average precipitation of 535 mm (1958–2003) (Hao et al. in Carsologica Sinica 23(1):43–47, 2004). Over the past three decades, accelerated groundwater exploitation has caused water-table decline in the aquifer, reduction of the spring discharge, and deterioration of water quality. In this study, three protection zones were defined to ensure the quality and capacity of this resource. The confluence of the 11 spring systems and the discharge areas were defined as I protection zone, the recharge basin was II protection zone, and the slack water area where there is little surface recharge was the III protection zone. Management strategies for each zone were suggested and evaluated to provide a scientific foundation for sustainable utilization.     

Characterizing the interaction of groundwater and surface water in the karst aquifer of Fangshan,Beijing (China)

Correct understanding of groundwater/surface-water (GW–SW) interaction in karst systems is of greatest importance for managing the water resources. A typical karst region, Fangshan in northern China, was selected as a case study. Groundwater levels and hydrochemistry analyses, together with isotope data based on hydrogeological field investigations, were used to assess the GW–SW interaction. Chemistry data reveal that water type and the concentration of cations in the groundwater are consistent with those of the surface water. Stable isotope ratios of all samples are close to the local meteoric water line, and the ³H concentrations of surface water and groundwater samples are close to that of rainfall, so isotopes also confirm that karst groundwater is recharged by rainfall. Cross-correlation analysis reveals that rainfall leads to a rise in groundwater level with a lag time of 2 months and groundwater exploitation leads to a fall within 1 month. Spectral analysis also reveals that groundwater level, groundwater exploitation and rainfall have significantly similar response periods, indicating their possible inter-relationship. Furthermore, a multiple nonlinear regression model indicates that groundwater level can be negatively correlated with groundwater exploitation, and positively correlated with rainfall. The overall results revealed that groundwater level has a close correlation with groundwater exploitation and rainfall, and they are indicative of a close hydraulic connection and interaction between surface water and groundwater in this karst system.     

西南岩溶山区地下水资源评价方法对比研究——以寨底地下河流域为例

西南岩溶山区地下水资源丰富,查清地下水资源量是科学管理水资源的基础,岩溶山区地下水资源量的评价方法多样,计算过程不同,进而评价结果也存在差异。本文选择寨底地下河流域为研究对象,采用四种不同的评价方法（总排泄量法、基流分割法、径流模数法、数值模型法）对流域地下水资源量进行评价,分析各方法的评价机理和流程,研究其主要影响因素,并对其适用性进行讨论。结果显示:针对西南岩溶石山地区,基流分割法简单快捷,适用于枯季地下水资源量评价,在雨季地下水资源量评价中存在一定不足;总排泄量法的评价结果较为准确,但资料获取难度大,且成本较高;数值模拟法运算高效,但需要大量的前期调查研究数据资料;径流模数法操作性较强,对岩溶山区具有较强的适用性,但参数的选择存在一定的不确定性,对评价结果影响较大。确定计算参数是水资源评价中的关键步骤,通过实测流量反推和灰色聚类法,可提高参数精度和计算效率。      

兰村泉域地下水污染原因及可持续开发利用对策研究

为确保兰村泉域地下水资源的可持续开发利用,在现场踏勘及有关资料分析的基础上,对泉域地下水污染原因进行了研究。结果表明,兰村泉域地下水污染与以下因素有关:(1)污染物入渗;(2)地下水开采;(3)水环境化学条件变化;(4)部分地区地下水原生本底值异常。提出了泉域地下水可持续开发利用对策。研究成果为兰村泉域地下水资源保护与管理提供科学依据。     

基于水文地质条件分析的岩溶水源地保护区划分

以邢台百泉岩溶水系统为例,分析了邢台百泉岩溶水系统的地下水流场受人类活动影响的演变特征,并采用数值模拟法预测了超采条件下水源地未来十年流场的变化。首次发现了泉域矿山疏排水形成了“沙河人工分水岭”并迅速北移的现象,标志百泉泉域地下水资源恶化严重,提出了在复杂岩溶水文地质条件下,采用以计算流程的方法划分保护区造成保护区浪费和碳酸盐岩裸露补给区没有保护的问题。在兼顾水质保护和水资源量可持续利用的前提下,分析了水源地上覆地层的防护能力和碳酸盐岩裸露补给区矿山疏排水对水源地的影响,将碳酸盐岩裸露补给区划分为二级保护区,突破了传统的“二级保护区包裹一级保护区”的模式,以较小的保护区面积有效地保证水源地的水质安全和可持续利用。      

Comprehensive analysis and quantitative evaluation of the influencing factors of karst collapse in groundwater exploitation area of Shiliquan of Zaozhuang, China

Karst collapse is a type of complicated environmental and geological hazard that can be caused by many factors: natural factors, such as rainfall, and human activities, such as overpumping of groundwater. Therefore, it is important to make a comprehensive analysis and evaluation on karst collapse risks and impacts of the influencing factors of karst collapse. However, how these factors affect karst collapse is still a problem, which has not yet been well solved. Taking the karst collapse in groundwater exploitation area of Shiliquan of Zaozhuang, China, as the example, and based on the comprehensive analysis of the formation rule and mechanism of karst collapse in this area, this paper mainly employs Quantification Theory to make a quantitative analysis and evaluation of various influencing factors of karst collapse in the groundwater exploitation area of Shiliquan of Zaozhuang. It thereby determines the impact of different influencing factors on karst collapse strength, and identifies the dominant and minor factors that affect the karst collapse. It also provides some criteria for the prevention of karst collapse and protection of karst water resources and environment.