共查询到19条相似文献，搜索用时 140 毫秒
1.
蒙新高原湖泊水质状况及变化特征 总被引：5，自引：3，他引：2
蒙新高原位于干旱/半干旱气候区,区内湖泊众多,但多为盐湖和咸水湖.近年来,由于湖泊咸化、萎缩甚至干涸的过程加快,区内多数湖泊水资源严重短缺,湖泊及其流域的生态环境遭遇巨大破坏.本文选取蒙新地区11个淡水和微咸水湖泊,通过对不同区域和不同类型的湖泊水质状况分析和对比研究,揭示蒙新地区湖泊水质现状及其变化特征与原因.结果表明,新疆地区湖泊类型多样,湖水阴、阳离子涵盖了各种水化学类型,而内蒙湖泊均为钠组-氯化物型.不同湖泊间湖水离子浓度和矿化度差异较大,湖水交换是蒙新地区湖泊水体矿化度的主要影响因素;与1988年相比,哈纳斯湖、阜康天池和赛里木湖等山地湖泊矿化度无明显变化或呈下降趋势,反映了区域气候变化特征;柴窝堡湖和红碱淖湖水矿化度快速升高,而达里诺尔水体矿化度增幅较小,其差异反映了修筑水库、地下水开采等人类活动在湖泊水环境变化中的不同作用.近50年来,乌伦古湖、博斯腾湖、吉力湖和乌梁素海水体矿化度波动升高,尤其近年来矿化度升高趋势加快,反映了流域内工农业等人类活动增强而导致入湖污染物增加以及气候干旱引起湖水浓缩两个方面所产生的叠加效应. 相似文献
2.
青海湖是青藏高原的重要组成部分,它是维系青藏高原东北部生态安全的重要水体.其沿岸地下水的排放直接影响了青海湖的水文生物地球化学过程,然而对该问题的研究仍然不充分.本研究于2014年对青海湖泉湾湖水、河水和地下水进行223Ra和224Ra活度的测定分析,并对泉湾湖水水平向和垂直向的Ra活度分布进行深入分析,最后估算并探讨了泉湾水体的停留时间和布哈河口沿岸地下水的排放通量.表层湖水、河水、地下水不同端元的水体223Ra和224Ra活度值分别为0.441和0.026 dpm/100 L、0.22和0.016 dpm/100 L以及0.061和1.30 dpm/100 L,最高值为地下水,其次湖水,河水最小;总体上泉湾湖水223Ra和224Ra活度随离岸距离增加分别由0.047到0.011 dpm/100 L和1.4到0.2 dpm/100 L的减小,垂向上Ra活度呈楔形分布,Ra活度在不同方向上的非保守性分布主要受到悬浮颗粒物解析的影响;通过水体滞留时间模型计算获得青海湖泉湾水体的平均停留时间为1.8天,进一步分析泉湾水体Ra的源汇项,应用镭同位素质量平衡模型获得泉湾布哈河口沿岸地下水排放通量为0.054～0.109 m3/(m2·d). 相似文献
3.
详细阐述了马湖的地理位置、湖盆形态、流域水系特征及湖区自然概况。从研究水资源的角度出发,实测了水下地形,并进行了湖水的水量平衡分析计算。分析湖水的理化特性,包括:水色、透明度、温度、溶解性气体、pH值、营养物质、矿化度和水型等,并根据其水资源特点,提出了开发和综合利用的措施。 相似文献
4.
水是人类生存之源,而湖荡被称为地球之“肾”,是河湖水系连接的关键缓冲节点,与人类生存和发展息息相关。长三角平原水系众多,河流纵横,天然湖泊与人工沟渠遍布,平原湖荡湖水与周边地下水的水力联系较为频繁,而地下水对湖泊水均衡贡献尚不明确,对平原湖荡地下水赋存和运移规律的认识不足。本研究以苏州吴江区元荡湖为研究对象,选取氡同位素作为湖水和地下水水力交换过程的示踪剂,建立氡箱模型,揭示元荡湖不同区段与地下水的水力联系过程和补给关系,并通过水位动态验证分析湖水—地下水交互关系。枯水期元荡湖水位和氡浓度空间分布特征指示研究区内地下水向湖水排泄,其中以湖泊西侧较为明显,地下水入流补给的氡为7.137×106 Bq/d,输入量源项占比为90%,地下水流入量为4540.801 m3/d,地下水每日流入量对元荡湖水量的贡献率为2.551%。参数敏感性分析结果表明,风速与地下水222Rn活度为特别敏感参数,取值差异较大时会导致计算误差急剧增大,改善测点布置和提高模型参数精度能有效提高模型计算结果的准确性和可靠程度。借助氡同位素示踪方法,建立湖泊氡箱模型,是研究平原湖荡内地下水补、径、排特征的有效方法。本研究在一定程度上加深了对平原湖荡区域水量均衡的认识,有助于了解平原湖荡水均衡和水循环机制,为平原湖荡水资源开发利用与环境保护提供数据支撑。 相似文献
5.
天津市北塘水库水质咸化原因和防治对策 总被引：3，自引：0，他引：3
为确定天津市北塘水库作为南水北调供水调节和事故备用水库的水质安全性,于2005年7-12月,监测分析水体、底泥和库周土壤中全盐量和Cl-浓度的变化,研究水源补给、底泥释放、降雨蒸发和地下水水位变动等因素对水库水质的影响.结果表明在目前蓄潮白新河水的条件下,北塘水库水中的Cl-浓度变化幅度为302-409 mg/L,超过饮用水水源地的水质标准(GB3838-2002).库区0-100 cm底泥全盐量平均值为0.253%,Cl-含量为0.048%,分别是库周土壤的1/8和1/18.3.因此,蓄水造成水库底泥盐分的大量释放.经计算,Cl-的平均释放强度为1.3g/(m2·d).南水北调通水后,若水库保持在5.60m以上的运行水位,底泥释放虽造成Cl-浓度上升,但水质能达到供水水源地的标准.水库周边地下水的矿化度为59.63g/L,Cl-浓度为26.17 g/L,远高于水库水体的含盐量,但只要在5.60m以上水位运行,水库就不会受到高矿化度地下水的补给影响.因此,在合理调度的基础上,北塘水库作为天津市南水北调供水调节和事故备用水库是安全的. 相似文献
6.
博斯腾湖水盐动态变化(1951-2011年)及对气候变化的响应 总被引：5，自引：1，他引：4
分析了1951-2011年博斯腾湖历史水位和湖水矿化度的动态变化特征,解析了博斯腾湖水量与水质对气候变化的响应及未来变化趋势.结果表明,博斯腾湖水位在60年内经历了两个突变时期,突变时间分别为1974年和1994年,湖水矿化度也相应地呈现了三个动态变化阶段,水量与水位呈极显著负相关,但水质变化滞后于水位变化1年;流域气温呈显著增加趋势,气温升高的突变时间为1993年,与开都河出山口径流突变时间一致,但降水变化不显著;1993年前,博斯腾湖水量主要受气温和人类活动双重影响,1993年后博斯腾湖水量主要受气温的显著影响,气温主要通过改变入湖水量及湖区蒸发损耗来调控湖泊水位和水质;未来气温持续升高情景下,博斯腾湖水位将面临降低趋势,水质也将有恶化趋势.因此,为合理开发利用博斯腾湖水资源,减少水资源无效损耗,抑制水质恶化趋势,确保流域可持续发展,建议将博斯腾湖调水时间集中在5-9月,并严格控制孔雀河流域工农业用水量及工农业、生活污染源,减少污水排放量,减少周边地下水开发量. 相似文献
7.
位于阿拉善高原的巴丹吉林沙漠分布有大量盐湖.为揭示盐湖分层特征以及地下水对盐湖水体的影响,选取沙漠腹地的第二大盐湖——苏木巴润吉林,对9月份湖水的温度和电导率剖面进行了观测.结果表明,尽管所测盐湖宽深比大于90,还是存在温跃层.温跃层的矿化度(TDS)为60~160 g/L,靠近湖底的水体存在TDS低值异常区,形成化跃层,推测为地下淡水集中排泄所致.这种湖底泉在其它较浅的盐湖水体中也存在,说明深、浅层地下水对盐湖水分及盐分都有贡献.温跃层水温随深度的变化近似符合静止水体的热传导规律,并没有受到地下水排泄热量的显著影响.研究区盐湖跃层的季节性变化还有待进一步研究. 相似文献
8.
巴丹吉林沙漠湖泊水分补给机制的模拟——以苏木吉林湖区为例 总被引：1，自引：0，他引：1
巴丹吉林沙漠气候干旱,蒸发强烈,与之形成鲜明对比的是沙漠腹地湖泊群的长久不衰,目前对于湖泊水分的补给来源仍存在争议.本文以水量均衡为基础,在苏木吉林湖区开展了降水、蒸发及湖水位和地下水位的动态监测,结合已有的水文地质资料建立地下水流动三维模型,重现湖区地下水位的季节动态变化,并基于模型进行水均衡分析.结果表明:苏木吉林湖区降水入渗补给量不足以平衡湖泊蒸发量,湖泊需要深层承压水的越流补给;湖水位和地下水位均呈现正弦曲线形态,11月最低,4月达到峰值,水位变幅分别为22和18 cm;湖区地下水多年平均总补给量为11620 m3/d,其中降水和承压水越流分别约占13%和87%,降水补给量夏季高、冬季低,承压水越流补给量季节变化不明显;承压水越流补给量可能主要来源于沙漠周边山区降水,未发现明显的水量亏空需要断裂导水来弥补.研究结果为巴丹吉林沙漠地下水资源分析及合理利用提供科学依据. 相似文献
9.
民勤绿洲地下水开采时空动态模拟 总被引：7，自引：0，他引：7
地统计学方法的应用已由最初的地质学领域广泛推广到土壤学、生态学等领域, 但在地下水特征的时空模拟方面应用还较少, 结合地理信息系统(GIS), 运用地统计学方法分析了石羊河下游民勤绿洲近15年来地下水特征的时空变异规律及其与土地利用变化的关系, 并对其变化趋势进行了预测. 得到了如下结果: (1) 地下水埋深的随机变异特征随着开采强度的不断增大, 从1987年的26.32%降到了2001年的0.03%, 完全被较大尺度上的结构性变异所取代; 而矿化度一直是中尺度上的结构性变异高达99.9%. (2) Kriging插值结果表明, 民勤绿洲地下水埋深的分布一直是水质较好的绿洲南部最深厚, 从南到北随着水质变差, 埋深也变浅. 地下水矿化度在空间分布上从南到北逐渐增大; 在变化趋势上, 高矿化度等值线由北向南持续推进. (3) 民勤绿洲近15年来耕地面积增加了3.1×104 hm2, 使得分布于地下水埋深17 m以上的耕地面积净增528.3 km2, 分布于地下水埋深11 m以下的林地减少200 km2. 同样, 分布于地下水矿化度3.0 g/L以上的耕地面积净增2×104 hm2, 其中>4.5 g/L的增加了1.072×104 hm2. (4) 预测至2015年, 地下水埋深下降趋势明显, 分布于地下水埋深20 m以上的绿洲面积将净增1689.88 km2, 达整个绿洲面积的68%; 至2015年地下水矿化度高于5.0 g/L的绿洲面积将达578.15 km2, 全部集中在水质较差的绿洲湖区最北部, 部分区域甚至高达7.0 g/L以上. 相似文献
10.
11.
Coupling of groundwater and surface water at Lake Willersinnweiher: Groundwater modeling and tracer studies 总被引：1，自引：0，他引：1
Ute Wollschläger Johann Ilmberger Margot Isenbeck-Schröter Andreas M. Kreuzer Christoph von Rohden Kurt Roth Wolfgang Schäfer 《Aquatic Sciences - Research Across Boundaries》2007,69(1):138-152
12.
The level of Lake Tana, Ethiopia, fluctuates annually and seasonally following the patterns of changes in precipitation. In this study, a mass balance approach is used to estimate the hydrological balance of the lake. Water influx from four major rivers, subsurface inflow from the floodplains, precipitation, outflow from the lake constituting river discharge and evapotranspiration from the lake are analysed on monthly and annual bases. Spatial interpolation of precipitation using rain gauge data was conducted using kriging. Outflow from the lake was identified as the evaporation from the lake's surface as well as discharge at the outlet where the Blue Nile commences. Groundwater inflow is estimated using MODular three‐dimensional finite‐difference ground‐water FLOW model software that showed an aligned flow pattern to the river channels. The groundwater outflow is considered negligible based on the secondary sources that confirmed the absence of lake water geochemical mixing outside of the basin. Evaporation is estimated using Penman's, Meyer's and Thornwaite's methods to compare the mass balance and energy balance approaches. Meteorological data, satellite images and temperature perturbation simulations from Global Historical Climate Network of National Oceanographic and Atmospheric Administration are employed for estimation of evaporation input parameters. The difference of the inflow and outflow was taken as storage in depth and compared with the measured water level fluctuations. The study has shown that the monthly and annually calculated lake level replicates the observed values with root mean square error value of 0·17 and 0·15 m, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
13.
Being a large hyper‐saline water body, Lake Urmia in north‐western Iran deals with a gradual decline in its water level. Most of the studies on Lake Urmia have neglected the groundwater issue. In this study, as a direct approach, the interaction between the groundwater level and the lake water level is investigated both in time and space by analysing the groundwater data compiled from observation wells surrounding the lake. Baseflow separation is considered as an indirect approach to understand the groundwater contribution to the river network flowing into the lake. It is determined that about 70% of run‐off in the rivers draining into the lake is born in the form of baseflow. An interaction between the lake and the groundwater storage is clearly seen from the analysis to conclude that groundwater has a potential to recharge the lake. Thus, the shrinkage of water level in Lake Urmia could be expected to accelerate with the drastic use of groundwater, which will be a disaster with no return. 相似文献
14.
《水文科学杂志》2013,58(3):418-431
Abstract The water balance of the closed freshwater Lake Awassa was estimated using a spreadsheet hydrological model based on long-term monthly hydrometeorological data. The model uses monthly evaporation, river discharge and precipitation data as input. The net groundwater flux is obtained from model simulation as a residual of other water balance components. The result revealed that evaporation, precipitation, and runoff constitute 131, 106 and 83 × 106 m3 of the annual water balance of the lake, respectively. The annual net groundwater outflow from the lake to adjacent basins is 58 × 106 m3. The simulated and recorded lake levels fit well for much of the simulation period (1981–1999). However, for recent years, the simulated and recorded levels do not fit well. This may be explained in terms of the combined effects of land-use change and neotectonism, which have affected the long-term average water balance. With detailed long-term hydrogeological and meteorological data, investigation of the subsurface hydrodynamics, and including the effect of land-use change and tectonism on surface water and groundwater fluxes, the water balance model can be used efficiently for water management practice. The result of this study is expected to play a positive role in future sustainable use of water resources in the catchment. 相似文献
15.
Abstract Kanchanapally watershed covering an area of about 11 km2 in Nalgonda district, Andhra Pradesh, India is located in granitic terrain. Groundwater recharge has been estimated from a water balance model using hydrometeorological data from 1978–1994. The monthly recharge estimates obtained from the water balance model formed input for the groundwater flow model during transient model testing. The groundwater flow model has been prepared to simulate steady state groundwater conditions of 1977 using the nested squares finite difference method. The transient groundwater flow model has been tested during 1977–1994 using the estimated recharge values. The present study helped verify the usefulness of monthly recharge estimates for accounting dynamic variations in recharge as reflected in water level fluctuations in hydrographs. 相似文献
16.
《水文科学杂志》2013,58(6)
Abstract Abstract The water balance of Lake Nainital in the Kumaun Himalaya, India was previously computed using water budgeting and other indirect methods. An important data set of stable oxygen and hydrogen isotopic composition of water sources of the lake region was also presented and used to verify the annual estimates of subsurface flow/water balance. In the present study, the same data set has been used to investigate the dynamics of this lake in terms of the seasonal processes operative during the annual hydrological cycle: increased inflow during the monsoon, delayed groundwater inflow, and stratification and mixing of water. Based on the available data, a simple two-box model was used to constrain the values of exchange coefficients between the hypolimnion and epilimnion layers and to estimate evaporation and outflow components from the isotopic data. 相似文献
17.
Comprehensive studies on the spatial distribution, water quality, recharge source, and hydrochemical evolution of regional groundwater form the foundation of rational utilization of groundwater resources. In this study, we investigated the water levels, hydrochemistry, and stable isotope composition of groundwater in the vicinity of the Qinghai Lake in China to reveal its recharge sources, hydrochemical evolution, and water quality. The level of groundwater relative to the level of water in the Qinghai Lake ranged from −1.27 to 122.91 m, indicating most of the groundwater to be flowing into the lake. The local evaporation line (LEL) of groundwater was simulated as δ2H = 6.08 δ18O-3.01. The groundwater surrounding the Qinghai Lake was primarily recharged through local precipitation at different altitudes. The hydrochemical type of most of the groundwater samples was Ca-Mg-HCO3; the hydrochemistry was primarily controlled by carbonate dissolution during runoff. At several locations, the ionic concentrations in groundwater exceeded the current drinking water standards making it unsuitable for drinking. The main source of nitrate in groundwater surrounding the Qinghai Lake was animal feces and sewage, suggesting that groundwater pollution should be mitigated in areas practicing animal husbandry in the Qinghai-Tibet Plateau, regardless of industrial and urbanization rates being relatively low in the region. The scientific planning, engineering, and management of livestock manure and wastewater discharge from animal husbandry practices is a crucial and is urgently required in the Tibetan Plateau. 相似文献
18.
通过对现代乌伦古湖附近出露的古湖相沉积剖面的AMS~(14)C测年,粒度、总有机碳、总有机氮以及碳酸盐等环境代用指标的分析及其与全新世钻孔沉积记录的对比研究,结果发现:乌伦古湖在MIS-3晚期的33600-22500 cal a BP以及冰后期至早中全新世的16500-6500 cal a BP期间,维持着湖相沉积环境,湖面约比现在湖面高40 m.33600-22500 cal a BP的MIS-3晚期,气候相对温暖,乌伦古湖呈现高湖面特征,湖泊沉积物来源以流水搬运为主;22500-16500 cal a BP的末次冰期冰盛期,气候寒冷干燥,湖泊沉积物来源以风力搬运为主;16500-6500 cal a BP的冰后期以及早、中全新世期间,气候回暖,湖泊沉积物主要来源于河流径流作用.6500-5500 cal a BP,受高温干旱事件的影响,湖面收缩、水位剧降,除沉积中心外的其它钻孔位置出现沉积中断.5500 cal a BP后气候转冷变湿,湖泊重新恢复到现在的状态.乌伦古湖MIS-3晚期以来的古湖相沉积环境变化及其反映的古气候万年尺度上的干湿变化与周边区域气候环境变化记录有很好的一致性,响应了区域环境变化和全球气候突变事件.季风和西风的强度消长变化及其引起的环流条件改变以及温度变化引起的蒸发效应可能是区域气候环境变化的主要原因.这一古湖相沉积记录的研究可为MIS-3晚期以来北疆地区的古湖泊演化以及长时间尺度上西风和季风环流相互关系及其影响区的气候环境演化提供地质证据. 相似文献
19.
基于水平衡模型的呼伦湖湖泊水量变化 总被引：2，自引：2，他引：0
针对北方寒旱区呼伦湖水位下降、水面萎缩的现象,根据气候特征,利用月水量平衡模型探究湖泊水文过程并揭示其变化规律.在此基础上,利用不同气候条件下各水平衡项对于湖泊水位的影响程度确定水位升降的直接原因.基于1963-1980年间水位的实测数据,根据水量平衡原理及其他辅助计算判断出湖泊与周边区域存在着地下水的交换,且具有一定的规律性,即历年11月至次年3月期间的累积降雪融化渗入土壤中形成浅层径流补给湖泊,而7、8月份湖泊补给周边草原.基于以上规律,根据周边坡面汇流、地下水与湖泊交换量的年内变化特征,利用水平衡方程式推算湖泊1981-2008年逐月水位变化,并与其他研究成果比较,吻合度较高.不同气候条件下,径流量对于湖泊水位的影响程度最为突出,是水位变化的主控因子. 相似文献