拉萨河流域地表径流氢氧同位素空间分布特征

为了探析径流过程中稳定同位素变化特征及其控制因子, 利用2008年拉萨河流域地表径流中δ18O和δD的监测数据以及相关气象和水文资料, 初步研究了流域δ18O和δD的空间分布特征.研究发现: (1)拉萨河流域以大气降水为主要补给来源, 且干流体现了较明显的蒸发效应; (2)河水偏正的d过量参数特征指示了冰雪融水的补给特征; (3)季风降水期间, 拉萨河流域由高程效应和水平距离所造成的δ18O递减率约为0.16‰·(100 m)-1; (4)大循环尺度下, 流域内河水呈现了明显的大陆效应.研究表明高海拔地区地表径流氧氘同位素分布特征能够有效示踪流域水文循环过程, 并提供古高度变化研究的稳定同位素证据.      

四川稻城地热资源的分布特点及温泉水的同位素地球化学特征

在分析四川稻城地区地热资源形成的地质背景的基础上，初步研究了该区地热资源分布特点和温泉水的同位素地球化学特征。结果表明，稻城县地热水的径流和排泄受构造作用的控制，断裂、断层地带地下径流多，是形成温泉的主要地区。在深大断裂发育处或断裂交汇地带，温泉往往成群出露。温泉水的同位素组成具明显的季节性效应；与大气降水季节性效应相反：夏季温泉水相对富轻同位素，冬季则明显富重同位素；反映其夏季主要受8D、δ^18O值低的高山常年积雪溶融水补给，冬季主要为8D、δ^18O值高的地下水补给。     

四川盆地卤水同位素组成及氘过量参数演化规律

运用岩石地球化原理对四川盆地卤水的同位素及氘过量参数进行分析,结果发现其具有明显的分布规律特征,盆地内以中三叠世为界同位素的显示出海、陆两大体系,海相沉积含卤层卤水中氢同位素组成均低于海水,而氧同位素则高于海水.卤水(主体)源于海水,不同时期海水的蒸发程度有所差异.由震旦系舍卤层卤水分布区向上,经寒武系、二叠系茅口组至三叠系嘉陵江组、雷口坡组,卤水的δD值随时代变新而相对富重同位素.陆相沉积含卤层卤水,源于大气降水,同位素组成落在大气降水线附近.海、陆过渡相含卤层(上三叠系须家河组)卤水,同位素组成落在海相沉积含卤层卤水与大气降水端员之间,系大气降水和蒸发海水的混合.盆地内不同时代的含卤层,卤水的氘过量参数(d值)有明显随含卤层时代变老逐步降低的趋势.三叠系雷口坡组-嘉陵江组、二叠系茅口组、寒武系及震旦系含卤层均系碳酸盐地层,水/岩作用十分强烈,同时显示出卤水的氘过量参数的变化是时间的函数.所有含卤层,凡是分布于盆地周边或处在断裂构造发育或经过长期开采卤资源的卤井,明显受到大气降水渗漏补给的影响,它们的氘过量参数(d)都有不同程度的升高,升高的程度取决于现代大气降水混入的数量.三叠系不同组含卤层的卤水,卤水d值的变化与平面分布和含卤层的埋深有一定的关联,含卤层埋深愈深,卤水的氘过量参数(d)值就愈低.     

新疆阿勒泰地区地表水体氢氧同位素组成及空间分布特征

氢氧同位素可以识别水体来源,示踪水循环,自20世纪50年代以来已被广泛应用于水文地球化学领域。已有学者开展了新疆大气降水及部分河流湖泊的稳定同位素研究,而关于阿勒泰地区大气降水之外的地表水体稳定同位素研究尚需加强。本文采用液体水激光同位素分析法开展了新疆阿勒泰地区地表河水、湖泊、山泉水、雪水、锂矿坑裂隙水五类水体的氢氧同位素组成研究。结果表明：阿勒泰地区各种类型水体氢氧同位素组成差异明显,地表河流的δ18O及δD值变化范围分别为-15.4‰~-11.5‰及-114‰~-100‰,氘过量参数（d值）变化范围为-12.4‰~12.4‰;乌伦古湖湖水的δ18O及δD值均远高于地表河流,平均值分别为-5.95‰及-78.5‰,氘过量参数远低于地表河流,均值为-30.9‰。地表河流与全球及乌鲁木齐大气降水线相比差异很大,河水除了大气降水外还受到冰川融水的补给,且在水循环过程中经历了蒸发分馏作用,地表河流之间的氢氧同位素组成差异主要受水体补给来源及蒸发程度强弱的控制。由于氢氧同位素温度效应、纬度效应等的存在,阿勒泰地区水体δD及δ18O与水温（T）、总溶解性固体（TDS）及主要离子Na+、K+、Ca2+、Cl-、SO42-摩尔浓度呈显著正相关关系,而与采样点纬度及溶解氧含量（DO）呈显著负相关关系（P < 0.05,n=32）。本研究获得的氢氧同位素组成特征为阿勒泰地区各类型水体稳定同位素研究提供了基础数据。     

地壳风化系统中的Sr同位素地球化学

近20年来,人们利用Rb－Sr同位素体系对地表－近地表地球化学过程、尤其是水圈－岩石圈之间化学物质的循环进行了广泛而深入的研究。大陆地壳风化物质以及地表径流的Sr同位素组成变化揭示了不同流域盆地的地质背景和风化作用的特征。古海洋的Sr同位素组成变化则是地壳和地幔演化以及不同地质历史时期壳－幔相互作用的共同结果。本文对地壳风化系统Sr同位素地球化学研究的全面而详细的综述表明,Rb－Sr同位素体系仍将是研究地壳风化、水圈－岩石圈之间化学物质循环的重要手段,根据古海水及其化学沉积物的Sr同位素记录研究壳－幔演化和地球圈层演化过程中的物质循环特征以及地表古环境变化将是本研究领域的重点。     

氢氧同位素在岩溶山区地下水循环条件研究上的应用——以贵州省镇宁地区为例

通过对贵州镇宁地区地下水调查取样,测定氢氧同位素组成,计算氘过量参数(d)表明,不同取样点δD、δ18O、d值差异明显,δD值范围为-77‰ ～-53‰,平均值-63.7‰;δ18O值变化范围为-11.1‰ ～-7.8‰,平均值-9.3‰;d值变化范围为9.4‰ ～ 12.6‰,平均值11‰.对镇宁地区地下水环境同位素...     

水体稳定同位素在青藏高原大气环流研究中的应用

水体稳定同位素作为贯穿水循环的介质,是研究大气环流过程和传输路径的有效手段。介绍了水体稳定同位素技术在青藏高原大气环流研究中的应用,聚焦典型站点降水、河水和冰芯等水体稳定同位素的季节和空间变化特征,揭示了大气环流对地表水稳定同位素高程效应的显著影响,以及大气降水对地表水的主导;引入降水稳定同位素标准判断亚洲夏季风爆发时间;通过冰芯稳定同位素揭示了厄尔尼诺—南方涛动对整个青藏高原水循环的影响及其响应机制的区域差异。在未来的研究中,将加强跟地球系统模型的结合,关注水体稳定同位素在不同时间尺度的控制因子、突变过程以及激发机制,进而量化古气候替代指标中的稳定同位素变化、从较长的时间尺度上重建影响青藏高原的水汽来源的演变历史。同时关注过量氘等具有水汽来源诊断能力的参数,研究其与大尺度环流参数的相关性,从海表温度、蒸发等陆—气相互作用分析并将高原环流过程与全球环流过程紧密结合综合分析。     

高原山地土壤冻融对径流形成的影响研究进展

亚洲主要江河的水源补给受到山地高原寒冻环境的影响,高寒山区积雪和冻土影响了江河源头的径流形成条件,是高寒环境下的具有固液两相变化的径流形成机制,在全球气候变化的大背景下对亚洲主要河流的径流变化和水资源供给具有重要作用。其中冻土的分布、发展和消融是决定该区域径流形成的一个关键环节,研究和揭示土壤冻融对径流形成的影响机制,成为研究全球气候变化和水资源安全领域的热点。要认识亚洲主要江河源头径流变化规律,预测气候变化条件下西部主要河流水资源动态,需要攻克高山(高原)地表环境要素对冻土格局的影响机制,高寒山区土壤冻融和地下水分的转化条件与阈值,冻土产汇流模型及相关参数确定方法,相关冰雪冻融—径流形成关系等关键环节。通过高寒地区冻土水文观测、土壤冻融模拟实验和基于热力学的土壤水多相转化模式的研究,将在冻土水文学的微观机制、尺度效应以及预测能力等方面获得新的认识,建立适合高寒山区的多尺度分布式流域水文模型,使寒区水文过程预测预报达到更高的水平。     

祁连山古浪河流域径流组分特征

为了探究气候变暖、冰冻圈急剧萎缩背景下祁连山内陆河的水文状况,依据古浪河流域所采集的各类水体样品和相关观测数据,分析了各水体稳定同位素特征及其所指示的环境意义,并进行了径流分割。结果表明：（1）与降水相比,河水稳定同位素年际变化较小,从季节变化角度来看,河水δ¹⁸O值夏季 > 秋季 > 春季 > 冬季,反映了不同季节蒸发强度的差异。（2）泉水稳定同位素特征与河水相似,年际变化较为稳定,表明山区河水与泉水之间可能存在转换过程。（3）由于土壤水分交换、地表土壤蒸发、植被蒸腾以及土壤水和地下水之间的同位素差异,引起土壤水同位素组成的梯度差异比较明显,土壤水δ¹⁸O由地表向下经历了富集―贫化―富集的过程,d-excess变化则与之相反。（4）径流分割结果显示大气降水对古浪河流域出山径流的补给率高达76%±2.4%,冻土层上水补给为24%±2.4%。     

云贵高原湖泊沉积物碳酸盐和有机质的同位素组成及环境信息记录

云贵高原湖泊沉积物碳酸盐和有机质的同位素组成及环境信息记录＠肖保华￥中国科学院地球化学研究所高原湖泊,碳酸盐,有机质,碳同位素,地球化学记录,环境气候信息云贵高原湖泊沉积物碳酸盐和有机质的同位素组成及环境信息记录肖保华（中国科学院地球化学研究所,贵阳５５０...     

新疆焉耆盆地水环境氢氧同位素特征及其指示作用

根据焉耆盆地开都河水及其两岸地下水中的氢氧稳定同位素资料及氘过量参数(d)值,分析了焉耆盆地内不同水体的δ(D)、δ(18O)和d值的分布规律,并得到地下水的主要补给来源及其与开都河水的相互作用关系;地下水的δ(D)在-87.60‰～-61.82‰间,δ(18O)在-10.90‰～-9.73‰间;开都河水的δ(D)在-71.95‰～-58.58‰间,δ(18O)在-9.57‰～-8.64‰间。结果表明:焉耆盆地内地下水和地表水同源于山区的降水和冰雪融水,且经历了较强的蒸发作用;地下水与地表水之间的直接水力联系较弱,深层地下水主要接受开都河水在洪积扇区的入渗补给,浅层地下水主要接受河流引水灌溉入渗;不同深度地下水之间的水力联系较为密切,为统一的地下水系统。     

塔里木河流域水文特性分析

塔里木河是我国最大的内陆河,历史上是九大水系144条河流的总称.由于气候变化和人类活动影响生态环境急剧恶化,目前形成了"四源一干"的格局.根据水文气象监测资料,从50 a来流域内的降水、蒸发、径流、洪水、泥沙、水质等方面对塔里木河流域生态环境恶化的成因进行分析.     

Snowmelt runoff and groundwater discharge in Himalayan rivers: a case study of the Satluj River,NW India

The Himalayas are one of the largest cryospheric systems outside the Polar Regions, and include more than 12,000 glaciers spread over an area of about 33,000 km². The Himalayan glaciers and snow packs retreating at an accelerating rate, thereby creating an alarming situation for the huge population that resides in northwestern India and southeastern Pakistan, as they depend on surface water resources in the region and rivers emanating from the Himalayas. This work attempts to quantify the contribution of different sources such as glacial/ice/snow melt and groundwater discharge to the Satluj River using the stable isotopes based hydrograph separation method at Ropar (foot hill) and Yusufpur in plain of Punjab, India. A mass balance model of three-component mixing has been engaged using the values of δ¹⁸O and electrical conductivity of the river water, and its discharge fraction, to estimate the time-varying relative proportion of each component from July 2013 to January 2014. The proportion of glacier melt was found to peak up to ~?64% at Ropar and ~?15% at Yusufpur during the wet summer months. The fraction of groundwater discharge was found to vary between 10–20% at Ropar and 25–35% at Yusufpur (Punjab plain) over time. The observed trend of d-excess (deuterium excess) values of river water also suggests that the glaciers and snow packs at higher altitudes contain a significant fraction of snow derived from vapor originating in the Mediterranean region, driven by the mid-latitude westerlies known as western disturbances.     

基于同位素示踪降水在两极海冰质量平衡中的贡献

极地海冰在全球气候系统中扮演着重要角色。在全球变暖背景下,两极海冰范围呈现相反的变化趋势,即北极海冰显著减少,南极海冰则略有增加,然而目前对两极海冰不对称变化的驱动机制还存在争议。已有研究集中在海冰变化与温度的相互作用上,而对降水在海冰生消过程中所起作用则知之甚少。两极海冰的这种不对称变化可能与降水在海冰生消中起到的不同作用有关：降水在北极主要起到促进海冰消融的作用,而在南极主要起到促使海冰加积生长的作用。降水在两极海冰质量平衡中的贡献可以通过同位素示踪加以厘定,本文详细对比了同位素判别法、线性混合模型和贝叶斯混合模型等研究方法的不同特点及应用上的优劣。利用氧同位素（δ¹⁸O）和氘盈余（d-excess）建立的海冰同位素混合模型,可量化融池在北极海冰质量平衡中的贡献和雪冰在南极海冰质量平衡中的贡献。罗斯海是南极海冰增大最明显的区域,且各种起源的海冰类型齐全（冰针冰、雪冰、附加冰和小板冰）,通过三氧同位素（¹⁷O-excess）作为新的示踪同位素,可进一步量化罗斯海海冰质量平衡中四组分的贡献比,探究罗斯海海冰异常变化的生长机制。

     

Hydrochemistry and origins of mineralized waters in the Puebla aquifer system,Mexico

Significant upward movement of mineralized water takes place in the Puebla aquifer system. Preferential groundwater flow paths related to the geological structure and the lowering of the potentiometric surface are suspected to be the prime factors for this intrusion. A combined approach of geochemical and isotope analyses was used to assess the sources of salinity and processes that are controlling the changes in groundwater chemical composition in the Puebla aquifer. Geochemical and isotope data indicate that the likely source of increased solutes is mineralized water from the dissolution of evaporites of the Cretaceous age at the base of the Upper deep aquifer, which is deeper than the intakes of the shallow wells. Dedolomitization and cation exchange seems also to occur along flow paths where sulphate concentrations tend to increase. The deep regional flow paths controls the chemical stratification of groundwater in response to decreased heads through interconnecting vertical and horizontal pathways, such as in the Fosa Atlixco. The results also suggest that high sulphate concentrations originating in the Lower deep aquifer are currently affecting shallow production wells. It is concluded that hydrodynamic aspects together with hydrogeochemical characteristics need to be taken into account to correctly explain the hydrochemical evolution in the stratified aquifer.     

华北盆地地下热水的水动力条件及水化学响应

华北盆地地下热水的水文地球化学分带对水文地质动力分带有着积极的响应特征和很好的指示作用,自周边山区至华北盆地内部,自浅部向深部,地下热水的水质逐渐变差,18O漂移程度越来越大,2H过量参数d值越来越小,指示循环交替条件逐步变差。地下热水高矿化度带的分布特征说明西部、北部的太行山、燕山为华北盆地地下热水的主要补给区,鲁西南山区的补给比例相对较小。水化学的分布特征说明,在盆地平面和垂向上,存在砂岩类地下热水的向心流(渗入成因水)与离心流(沉积成因水)的水动力平衡带,反映了向心流与离心流是此消彼长的动态平衡关系。     

Uranium isotopes (234U/238U) in rivers of the Yukon Basin (Alaska and Canada) as an aid in identifying water sources, with implications for monitoring hydrologic change in arctic regions

The ability to detect hydrologic variation in large arctic river systems is of major importance in understanding and predicting effects of climate change in high-latitude environments. Monitoring uranium isotopes (²³⁴U and ²³⁸U) in river water of the Yukon River Basin of Alaska and northwestern Canada (2001?C2005) has enhanced the ability to identify water sources to rivers, as well as detect flow changes that have occurred over the 5-year study. Uranium isotopic data for the Yukon River and major tributaries (the Porcupine and Tanana rivers) identify several sources that contribute to river flow, including: deep groundwater, seasonally frozen river-valley alluvium groundwater, and high-elevation glacial melt water. The main-stem Yukon River exhibits patterns of uranium isotopic variation at several locations that reflect input from ice melt and shallow groundwater in the spring, as well as a multi-year pattern of increased variability in timing and relative amount of water supplied from higher elevations within the basin. Results of this study demonstrate both the utility of uranium isotopes in revealing sources of water in large river systems and of incorporating uranium isotope analysis in long-term monitoring of arctic river systems that attempt to assess the effects of climate change.     

Impact of transferred water on the hydrochemistry and water quality of surface water and groundwater in Baiyangdian Lake,North China

The hydrochemical composition of surface water and groundwater is a key parameter for understanding the evolution of water and its quality.In particular, little is known about the impact of transferred water on surface water and groundwater.In this study, Baiyangdian Lake was selected as a typical area for extensive groundwater exploration and surface water transfer in the North China Plain.Surface water and groundwater samples were sampled in dry/wet seasons and then analyzed before/after the water transfer, respectively.Generally, surface water and groundwater are extensively hydrologically connected based on hydrochemical evidence.It was found that the hydrochemical composition of the shallow groundwater is affected by the surface water and that the water quality of the deep groundwater is stable.However, inter-aquifer recharge processes from the shallow groundwater to the deep groundwater existed in the anthropogenic region impacted with high nitrate-ion concentrations.Also, the hydrochemical composition of the surface water and groundwater was dominated by rock-weathering and evaporation-precipitation processes.Due to the existence of the deep vadose zone in the alluvial fan, Na~+was exchanged into soil matrices during the leakage of the surface water.In addition, the transferred water resulted in surface water with good quality, and it also played as an important recharge source to groundwater.As the most important water resource for irrigation and drinking, deep groundwater should be paid more attention in the alluvial fan with frequent water transfer and extensive groundwater exploration.     

北极巴罗地区海冰消融初期表面特征及光谱反射率观测研究

北极海冰消融初期,上覆积雪急剧消融,融池开始形成,海冰表面物理特征异常复杂。由于观测资料缺乏,对这一时期海冰变化的研究仍存在较大不确定性。利用2015年5月份在巴罗Elson Lagoon海域观测的海冰表面物理特征和光谱反射率数据,分析了巴罗地区海冰消融初期表面积雪、裸冰和融池反射率特性及其影响因素。结果表明：消融初期,海冰表面异质性强,积雪、裸冰和融池相间分布。在积雪覆盖的区域,积雪对海冰光谱反射率起决定性作用,观测到不同雪深（3~23 cm）的反射率变化在0.53~0.85之间,平均反射率为0.76且反射率与雪深呈正相关。在表面积雪厚度相同的情况下,积雪底层含水量越大,表层反射率越小。观测还显示,在融池形成的区域,海冰的反射率急剧降低,融池初形成时反射率为0.206,略低于裸冰（0.216）。随着融池的发展,当其深度达到10 cm时,反射率仅为0.04,与开阔海域海水接近。     

Quantification and characterization of the dynamics of spring and stream water systems in the Berchtesgaden Alps with a long-term stable isotope dataset

The understanding of alpine groundwater dynamics and the interactions with surface stream water is crucial for water resources research and management in mountain regions. In order to characterize local spring and stream water systems, samples at 8 springs, 5 stream gauges and bulk samples of precipitation at 4 sites were regularly collected between January 2012 and January 2016 in the Berchtesgaden Alps for stable water isotope analysis. The sampled hydro-systems are characterized by very different dynamics of the stable isotope signatures. To quantify those differences, we analyzed the stable isotope time series and calculated mean transit times (MTT) and young water fractions (YWF) of the sampled systems. Based on the data analysis, two groups of spring systems could be identified: one group with relatively short MTT (and high YWF) and another group with long MTT (and low YWF). The MTT and the YWF of the sampled streams were intermediate, respectively. The reaction of the sampled spring and stream systems to precipitation input was studied by lag time analysis. The average lag times revealed the influence of snow and ice melt for the hydrology in the study region. It was not possible to determine the recharge elevation of the spring and stream systems due to a lack of altitude effect in the precipitation data. For two catchments, the influence of the spring water stable isotopic composition on the streamflow was shown, highlighting the importance of the spring water for the river network in the study area.