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1.
以昆明地震台井水、渔塘水为研究对象,通过水质、同位素分析方法并结合水文地质、构造地质等资料,探究井水地球化学特征及意义,以及井水与渔塘水之间的水力关系。研究结果显示：昆明地震台井水、渔塘水水化学类型为HCO3—Ca型,水质受含水层和隔水层岩性控制,与2018年相比2020年井水水化学特征发生了显著变化,K+、HCO3-浓度降低,这反映了昆明地震台井—含水层渗透性有所增加;SO42-、Cl-浓度的增加则表明昆明地震台井水会受到人为干扰。研究区构造活动平稳,井水为未成熟水,演化程度较低,因含水层渗透性增强和人为干扰,自2018年7月至2020年11月昆明地震台井水—岩作用有所增强,表现为δD、δ18O富集,Mg2+浓度升高。井水补给来源为大气降水,补给区位于观测井正北的石关一带。渔塘水与昆明地震台井水间存在水力关系,在分析地表水对昆明地震台井的影响时应予以考虑,但渔塘水不是影响井水的主要因素。 相似文献
2.
分析了山溪性城市河流水环境特征及其存在的问题,提出了水安全、水环境、水景观、水文化和水经济五位一体的综合整治模式,并阐明了其综合整治的具体内容.最后以丽水市内河水环境建设工程为例,详细介绍了山溪性城市河流的防洪排涝、供水、生态用水及水质安全的保障系统、水环境保护方案、水景观和水文化建设体系及水经济开发方案,为山溪性城市水环境的综合整治提供了借鉴. 相似文献
3.
为探究太湖梅梁湾水体及沉积物中微囊藻毒素（MC-LR、MC-RR、MC-YR）含量的垂向分布特征,于2018年5月采集梅梁湾6个点位表层水、上覆水、混合水、间隙水以及柱状沉积物样品,并采用超高效液相色谱-串联质谱法分析样品中微囊藻毒素的含量.分析结果表明：水体中（表层水、上覆水、混合水以及间隙水）MC-LR、MC-RR、MC-YR的浓度范围分别为11.80~1297.14、2.50~818.40、1.80~176.00 ng/L,表层水、上覆水以及混合水中MC-LR的浓度高于MC-RR和MC-YR,MC-RR和MC-YR之间差别较小,而间隙水中MCs三种异构体浓度大小顺序为：MC-LR > MC-RR > MC-YR;垂向分布上,间隙水中MCs异构体（MC-LR、MC-RR、MC-YR）浓度均远高于表层水、上覆水以及混合水,表层水MCs异构体浓度略高于上覆水,混合水MCs异构体浓度介于表层水和上覆水之间.对沉积物的研究发现,1~10 cm表层沉积物中MC-LR、MC-RR、MC-YR含量范围分别为0.60~26.95、0~0.90、0~8.10 ng/g,且1~10 cm层中MCs三种异构体平均含量大小顺序为：MC-LR > MC-YR > MC-RR,其中MC-LR、MC-RR、MC-YR的检出率分别为100%、70%、92%;垂向分布上,MC-RR含量较低且变化不大,而MC-YR和MC-LR含量均随沉积物深度的增加先升高后降低.相关性分析结果表明,表层水和混合水中MCs与总磷浓度呈显著正相关,而与总氮浓度无显著相关性;上覆水、间隙水以及沉积物中MCs与总氮、总磷浓度均呈显著正相关. 相似文献
4.
生态补水是维持和改善白洋淀生态环境的重要途径.为研究生态补水对白洋淀水环境的影响,分别在补水前与补水后采集淀水、河水及地下水样品,分析区域地表水和地下水水化学特征.结果表明：（1）白洋淀补水前、后地表水与地下水的水化学组成中Na+为主要阳离子,补水后阴离子以HCO3-为主,淀区南部地表水电导率高;补水后地表水与地下水Ca2+、Mg2+和HCO3-浓度显著增加,水体电导率降低.（2）补水前地下水为Na-HCO3型水,地表水主要为Na-Cl·SO4及Na-Cl·HCO3类型;补水后地表水与浅层地下水向Ca·Mg-HCO3型演化,深层地下水水化学类型基本保持不变.（3）生态补水使白洋淀水位升高,淀区水面积增大,缓解了水资源短缺的问题;同时也使浅层地下水水化学组成发生改变,而深层地下水暂未受到影响.生态补水后,受稀释和混合作用的影响,水体Na+、Cl-和SO42-浓度显著下降,Ca2+、Mg2+及HCO3-浓度增加.在白洋淀生态补水中应"先治污,后补水",以减少补水过程中污染物向淀区的运移,还应注意区域地下水位上升过程中的阳离子交换及水岩相互作用,为合理调配生态补水及改善白洋淀生态环境提供科学依据. 相似文献
5.
湖泊生态水位计算新方法与应用 总被引：6，自引：4，他引：2
水位是湖泊水文情势的主要特征指标,对湖泊的水量、水质和生物的栖息地等有直接或间接的影响,被认为是湖泊生态系统健康的关键影响因素.如何确定合理的湖泊水位以保证生态系统健康成为湖泊科学研究的重要科学问题.根据湖泊天然水位情势,从天然水文变化中识别多项反映完整水位过程的指标,构建了湖泊生态水位的计算方法.从湖泊天然水位情势中提取出高、低水位的历时、发生时间和变化率等水位指数来表征其生态水位.该方法弥补了传统湖泊生态水位计算方法仅给出最小生态水位的不足,体现了湖泊生态系统健康对水位过程的要求.基于提出的生态水位计算方法和鄱阳湖都昌水位站1952-2000年共49年的日均监测数据,计算了鄱阳湖的生态水位目标值区间,以期为鄱阳湖水利工程生态调度提供决策依据. 相似文献
6.
引调水是改善平原河网地区水环境的重要方法之一,通过构建太湖流域走马塘东南片平原河网区一维水动力水质数学模型,研究不同引调水方案对区域水环境改善效果,确定引调水过程中的异质性因子.从决策目标、水质指标、空间指标3个层面综合考虑,构建环境效益与经济效益结合的多目标函数及评价体系,对引调水方案进行评估优选.结果表明:引调水流量较大时,能够在一定程度上改善区域水环境状况,规划方案下引调水5 d后,高锰酸盐指数、氨氮、总磷的平均改善率分别为30.7%、22.2%、26.4%;引调水时,区域河网中不同空间点位、不同水质指标之间的水质改善过程与效果都存在一定异质性;引调水水量、调度模式及污染源分布都会对调水后的河网区水质产生差异性影响;本研究建立的多目标评价体系较现有方法能够有效涵盖引调水中存在的异质性因子,从多个目标层面优选引调水方案,实现水量水质综合优化调控,为平原河网地区水环境长效管理与科学决策提供理论参考. 相似文献
7.
南北同枯场景下南水北调中线丹江口水库供水调度是保障水源工程有效供给、优化配置供水水源的重要课题,如何科学制定不同供水对象的供水水量、兼顾水源区及受水区用水需求、充分发挥丹江口水利枢纽的调蓄作用,是南水北调中线工程功能效益发挥的关键.以南水北调中线水源工程丹江口水库为研究对象,深入分析了中线工程通水后丹江口水库供水现状及面临的技术难题,从而提出南北同枯场景的判别标准及相应水库供水调度的方法,揭示了汉江中下游、清泉沟和南水北调中线供水对水库起始供水水位的响应机理,提出"蓄丰补枯、均衡减少"的方法是南北同枯场景下丹江口水库的供水调度方式,不同供水起始水位及供水方式情况下供水调度仿真结果表明,本文所得结论可为丹江口水库在实际运行中制定调度方案提供参考. 相似文献
8.
Seasonally variation of water salinity is observed worldwide, the mechanisms of water salinity are not well understood due to natural factors and anthropogenic activities. Quantification water salinity source are challenging since complex influence factors, especially in agricultural regions irrigated with multi-water sources. In the lowland area of North China Plain, transferred water, brackish shallow groundwater and fresh deep groundwater were combinative utilized to relieve prominent contradictions between regional water shortages and grain production. In this study, influence factors of surface water (canal water, pond water) and shallow groundwater salinity were identified and quantified through statistical analysis, deuterium excess, and ionic relationship. Salinity of canal water and pond water increased in dry season and decreased in rainy season, while salinity of shallow groundwater decreased in dry season after water transfer and rainy season, but increased in dry season. Evaporation and mineral dissolution were main factors for surface water salinity in dry season, with mineral dissolution was the more important one. The contribution ratio of evaporation and mineral dissolution for canal salinity were 4.4 and 49.1% in dry season after water transfer, 7.1 and 34.4% in dry season, and that for pond water salinity were 12.4 and 18.3% in dry season, respectively. Precipitation and surface runoff were main factors for surface water salinity in rainy season. The contribution of surface runoff for canal water and pond water salinity were 66.1 and 45.8%, respectively. Salinity of canal water and shallow groundwater was temporary decreased by water transfer. Domestic sewage from rural areas had larger influence than agricultural activities for salinity increase of pond water and shallow groundwater. Mineral dissolution was the main contributor for shallow groundwater salinity, with contribution ratio larger than 60% in different periods. This study demonstrated and quantified salinity source of surface water and shallow groundwater and may deepen our understanding of water management under multi-water resources utilization. 相似文献
9.
热分层对水库水质的季节性影响——以西安黑河水库为例 总被引：3，自引：1，他引：2
深水水库作为城市的重要供水水源,通常由于热量在垂向水体上的不均匀分配形成热分层.热分层会阻碍垂向上水体交换引发水质分层现象,在冬季水库发生“翻库”之后,水体混合导致水库的整体水质下降.结合热分层指数可以客观、直接地表达水库热分层的稳定程度.综合水库的气温、水体更新率和水质参数(溶解氧、pH、总磷、氨氮)的年度变化,对陕西黑河水库2008-2010年的热分层状况进行研究.研究表明:水库的热分层形成会直接恶化底部水质尤其会加速底部水体中溶解氧的消耗;热分层的年度变化主要受气温控制,但在特定时期较大的水体更新率可以在一定程度上弱化水体热分层,减缓底部水质恶化.该结果可使水库管理者在水库分层最稳定、水质恶化最严重时期以人工调节水体更新率的方式弱化热分层,为保证水质安全提供参考. 相似文献
10.
黄河水资源贫乏,水污染严重,水资源供需矛盾日益尖锐,黄河流域水资源保护面临着诸多的困难和压力.新《水法》的颁布,给黄河水资源保护带来新的机遇和挑战,依法建立法制化、社会化的流域与区域相结合的水资源保护管理体系,完善法规,建立健全执法体系,以水功能区划管理为重心,实施入河总量控制,建立和完善重大水污染事件快速反应机制,加强水质监测机制与技术创新,加强水资源保护前期和科研工作,建设水资源保护信息管理系统,采取多部门联合治污等项措施,是做好黄河流域水资源保护工作的重要前提和任务. 相似文献
11.
An ecological and hydrochemical classification elaborated by the authors is used to assess the present quality of water in the most important water objects of the Republic of Armenia. This classification allowed us to determine the degree of environmental safety of each water body by ranking the water quality, ecosystem ecological stability, and the reliability of conservation of water quality during transportation. Based on the results of the ecological and hydrochemical assessment of water quality, the water bodies that require special protection and rational exploitation are distinguished, and the priority of water protection measures is established. 相似文献
12.
太湖是流域洪水集散地、水资源调配中心,也是长三角水生态环境的晴雨表,其水位高低影响防洪、供水、水生态、水环境等系统功能,使得太湖面临统筹调度问题日益凸显。本文以太湖为主要研究对象,基于多年实测数据,采用数理统计、河网水动力模型计算,分析流域降雨、进出湖水量和水生态环境演变规律及其与太湖水位的互馈关系,综合考虑不同调度期流域防洪、供水、水生态、水环境目标及其承受风险的时空差异性,优化太湖调度水位,并在此基础上提出太湖调度功能区划图。结果表明,在设计洪水和供水条件下,通过调度水位调整,统筹调控流域水工程,前期预降太湖水位,后期适抬太湖水位,实现太湖多目标调度,可有效保障流域防洪、供水和航运安全,改善河湖生态环境,共绘美丽太湖。 相似文献
13.
地热井的观测规范要求尽可能将水温传感器放置在井下深处, 一般放置深度应当大于100 m, 小于200 m。 然而, 近几年的观测结果表明, 水温传感器的放置深度对水温动态特征的影响较大。 在多数观测井中, 同井水温与水位的时值动态、 潮汐效应、 同震响应及震后阶变等动态特征的相关性或一致性, 多与水温传感器的放置深度有关。 本文主要探讨了传感器放置深度对水温动态特征的影响, 水温传感器放置在观测含水层中, 都受井—含水层间水流运动的影响, 会造成水温动态随井水位变化而变化; 当放置在观测含水层下部时, 水温动态则不受井水位变化的影响, 多表现为动态相对稳定。 其原因是水温动态的形成受水热动力学与地热动力学两种不同机制的控制, 此外, 井—含水层系统的条件也会产生影响。 相似文献
14.
自2000年庐江地震台数字化水位、水温观测以来,在多次大地震中水位、水温均有明显的同震效应,四川汶川8．0级地震、日本本州9．0级地震引起汤池1号井水位、水温的同震特征。动水位同震效应表现为脉冲变化,震后水位逐渐升高;水温表现为阶跃下降,震后水温缓慢恢复到正常状态。 相似文献
15.
非点源污染对太湖上游西苕溪流域水环境的影响 总被引：14，自引：3，他引：11
水资源短缺是全球性关注的问题,水质恶化更加剧了这一问题的严重性,定量研究水质变化及其影响凶素可为治理水环境提供基础依据．与实测数据及综合污染指数的对比表明,水质指数能够合理反映水质的变化程度和时空变化趋势．利用西苕溪流域1996-2000年水质监测数据的研究结果如下：西苕溪流域水质的空间变化趋势是自上游至下游逐渐恶化,时间变化的总体趋势是逐年转好;点污染源得到有效控制年份(1999年)的水质指数比以前年份(1996-1998年)有所提高但幅度不大,说明非点源污染是影响西苕溪流域水质的重要因素;流域水污染的主要形式是氮、磷污染,其主要非点源是农田、经济竹林和城镇径流及居民生活污水等． 相似文献
16.
As vegetation usually excludes salt during water uptake, transpiration will increase the salinity of the residual water. If the source water is sea water, then the residual water may become highly saline. In the unconfined coastal aquifer of the tropical Burdekin River delta, northeastern Australia, areas of highly saline ground water with chloride concentrations up to almost three times that of sea water occur up to 15 km from the present coastline, and are attributed to transpiration by mangrove vegetation during periods of high sea level. Radiogenic ((14)C) carbon isotope analyses indicate that ground water with chloride concentrations between 15,000 and 35,000 mg/L is mostly between 4000 and 6000 years old, at which time sea level was 2 to 3 m higher than present. Stable isotope analyses of oxygen-18 and deuterium show no evidence for evaporative enrichment of this water. Oxygen-18, deuterium, and stable (delta(13)C) carbon isotope analyses of ground water and soil water point to a recharge environment beneath the mangrove forests during this postglacial sea level high stand. During that period, transpiration of the mangrove forests would have led to high chloride concentrations in the residual ground water, without inducing isotopic fractionation. Due to the higher density, this hypersaline water moved downward through the aquifer by gravity and has formed lenses of highly saline ground water at the bottom of the unconfined aquifer. 相似文献
17.
《Limnologica》2015
Water level fluctuations due to reservoir operations often cause spatial and temporal differences in water chemistry, which in turn can have considerable biological effects. Nonetheless, few studies have investigated the effects of fluctuating water levels on water quality and benthic macroinvertebrates in reservoirs in tropical countries, and none in the Philippine archipelago. We investigated the littoral zone of a Philippine reservoir subject to strong water level fluctuations and determined whether (i) water quality and macroinvertebrate community health is reduced when water levels are low, (ii) water quality declines with increasing water depth regardless of the overall water level, and (iii) water quality and community health decrease more strongly with water depth during low water level periods. Our study included five sites and four depths at each site, with three collections each during high and low water levels. Low water levels may have negatively affected four water quality and 10 biological metrics, whereas depth may have negatively affected two water quality and five biological metrics. Significant overall water levels by depth interactions were detected for four common taxa but none for water physicochemistry. Our findings show that tropical reservoirs may experience reduced water quality at low water levels, which can affect their biodiversity and potentially their ecological functioning. 相似文献
18.
Impact of water transfer on interaction between surface water and groundwater in the lowland area of North China Plain 总被引：1，自引：0，他引：1 
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下载免费PDF全文 The contradiction between the freshwater shortage and the large demand of freshwater by irrigation was the key point in cultivated lowland area of North China Plain. Water transfer project brings fresh water from water resource‐rich area to water shortage area, which can in turn change the hydrological cycle in this region. Major ions and stable isotopes were used to study the temporal variations of interaction between surface water and groundwater in a hydrological year after a water transfer event in November 2014. Irrigation canal received transferred Yellow River, with 2.9% loss by evaporation during water transfer process. The effect of transferred water on shallow groundwater decreased with increasing distance from the irrigation canal. Pit pond without water transfer receives groundwater discharge. During dry season after water transfer event, shallow groundwater near the irrigation canal was recharged by lateral seepage and deep percolation of irrigation, whereas shallow groundwater far from irrigation canal was recharged by deep percolation of deep groundwater irrigation. Canal water lost by evaporation was 2.7–17.4%. Influence of water transfer gradually disappeared until March as the water usage of agricultural irrigation increased. In the dry season, groundwater discharged to irrigation canal and pond; 2.2–31.6% canal water and 11.3–20.0% pond water were lost by evaporation. In the rainy season (June to September), surface water was fed mainly by precipitation and surface run‐off, whereas groundwater was recharged by infiltration of precipitation. The two‐end member mix model showed that the mixing ratio of precipitation in pond and irrigation canal were 73–83.4% (except one pond with 28.1%) and 77.3–99.9%, respectively. Transferred water and precipitation were the important recharge sources for shallow groundwater, which decreased groundwater salinity in cultivated lowland area of North China Plain. With the temporary and spatial limitation of water transfer effects, increased water transfer amounts and frequency may be an effective way of mitigating regional water shortage. In addition, reducing the evaporation of surface water is also an important way to increase the utilization of transfer water. 相似文献
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Caroline A. Canham Clément Duvert Leah S. Beesley Michael M. Douglas Samantha A. Setterfield Fiona L. Freestone Steven Clohessy Robyn C. Loomes 《水文研究》2021,35(5):e14180
Riparian trees play a critical role in the ecological function of rivers, yet are threatened by anthropogenic change to the hydrological cycle. Identifying the sources of water used by riparian trees can inform sustainable water policy. We used isotopic analysis complemented by measurements of plant water relations to assess water sources for riparian trees at two sites with contrasting hydrogeological processes; one with an alluvial aquifer overlaying an aquitard, and one where fault-induced preferential pathways in the aquitard allowed the flow of deeper, older groundwater from a regional aquifer to the alluvium. At both sites, plant water potential, stomatal conductance, and plant water isotope composition in the xylem sap of riparian trees were collected from two landscape positions, the riverbank and floodplain. We used a Bayesian mixing model (MixSIAR) to assess differences in the proportion of water sources for sites and landscape positions. We found that xylem water isotope values differed between the two sites in line with their hydrogeological characteristics, with trees at the regional aquifer site using water sourced from the regional groundwater and trees at the site with only an alluvial aquifer present using a mixture of water sources, with no dominant source identified. Higher plant predawn water potential values at the regional site indicated greater water availability and support the inference that plants were using more groundwater at the regional site compared to the alluvial site. Trees closer to the river had higher isotope values, indicative of surficial water sources i.e. shallow soil water and river water. Our findings show that the water sources used by riparian trees reflect local hydrogeology and resource availability. Water managers should identify and protect plant water sources to ensure maintenance of riparian trees. 相似文献