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新疆博斯腾湖水盐变化及其影响因素探讨 总被引：11，自引：5，他引：11
在博斯腾湖水文和水化学实测资料的基础上，研究了博斯腾湖水盐的年际和年内变化。近40年来，水质年际变化经历了好→中→差→中的过程；年内变化与区内最大补给源开都河不同季节河流来水量变化以及湖周农田排盐水等因素直接相关，而湖水的矿化度与水位变化呈负相关。对湖水主要离子含量变化特点和湖区矿化度变化规律的研究表明，湖水补给源及湖水循环状况是影响湖水水质变化的主要因素。 相似文献
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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
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南四湖“三湖两河”洪水演算数值模型优化 总被引：1，自引：0，他引：1
南四湖是中国北方最大的淡水湖泊,由南阳湖、独山湖、昭阳湖和微山湖4个湖区串联而成,地形复杂,洪水易涨难消,与滨湖区涝水交换频繁,建立兼顾效率和精度的洪水演算模型复杂困难.基于1960s提出的用"三湖"和"两河"来概化模拟南四湖洪水的理念与"三湖两河"半图解法洪水演算模型,采用四阶龙格库塔法代替半图解法,改进"三湖两河"洪水演算模型,对比分析计算精度、效率和灵活性,"三湖两河"洪水演算数值解模型优于半图解法;分析了滨湖排水模数、"两河"传播历时等模型经验参数的敏感性,以及韩庄闸水位—流量关系变动对湖泊高水位的影响,据此提出了南四湖洪涝治理的若干建议.南四湖"三湖两河"洪水演算数值解模型可作为南四湖洪水管理的基础工具,因地制宜的建模思路对类似湖库具有重要参考价值. 相似文献
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“十三五”时期，长江流域水环境质量改善明显，但湖泊水质和富营养化状况改善滞后. 长江中游作为我国淡水湖泊集中分布区域之一，部分湖泊存在水环境质量恶化和富营养化加重问题. 本文以长江中游区域国家开展监测的洪湖、斧头湖、梁子湖、大通湖、洞庭湖和鄱阳湖这6个典型湖泊为研究对象，科学评价其2016—2020年水质和富营养化时空变化特征及关键驱动因素，探讨其成因及治理对策. 结果表明，“十三五”时期长江中游湖泊水质和富营养化程度存在较大差异，与2016年相比，2020年大通湖水质改善最为明显，梁子湖水质变差，总磷是影响长江中游湖泊水质类别的主要因子; 洪湖富营养程度恶化最为严重，斧头湖次之，TLI(SD)对长江中游湖泊富营养化评价贡献最大. 目前长江中游湖泊呈有机污染加重和叶绿素a浓度升高现象，洪湖、斧头湖和梁子湖主要与氮、磷营养盐浓度升高有关，而大通湖、洞庭湖和鄱阳湖受水文过程、流域纳污量和湖泊管理等非营养盐因素影响较大. 总氮和总磷仍然是影响“十三五”时期长江中游湖泊水质和富营养化的最主要驱动力，且各湖泊总氮和总磷浓度变化均具有较强正相关性，建议开展河湖氮、磷标准衔接工作，提出河湖氮、磷标准限值或考核目标，以完善河湖水环境质量标准和生态健康影响评价技术规范. 同时，建议长江中游湖泊在开展截污控源、内源控制和生态修复的同时，进一步深化流域管理，特别是对洞庭湖、鄱阳湖、梁子湖和斧头湖等跨行政区湖泊，以提高湖泊治理与修复的系统性和整体性. 相似文献
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AbstractA parametric uncertainty and sensitivity analysis of hydrodynamic processes was conducted for a large shallow freshwater lake, Lake Taihu, China. Ten commonly used parameters in five groups were considered including: air–water interface factor, water–sediment interface factor, surrounding terrain factor, turbulent diffusion parameters and turbulent intensity parameters. Latin hypercube sampling (LHS) was used for sampling the parametric combinations, which gave predictive uncertainty results directly without using surrogate models, and the impacts of different parametric distribution functions on the results were investigated. The results showed that the different parametric distribution functions (e.g. uniform, normal, lognormal and triangular) for sampling had very little impact on the uncertainty and sensitivity analysis of the lake hydrodynamic model. The air–water interface factor (wind drag coefficient) and surrounding terrain factor (wind shelter coefficient) had the greatest influence on the spatial distribution of lake hydrodynamic processes, especially in semi-closed bays and lake regions with complex topography, accounting for about 60–70% and 20%, respectively, of the uncertainty on the results. Vertically, velocity in the surface layer was also largely influenced by the two factors, followed by velocity in the bottom layer; the middle velocity had minimal impact. Likewise, the water–sediment interface factor (i.e. bottom roughness height) ranked third, contributing about 10% to the uncertainty of the hydrodynamic processes of the lake. In contrast, turbulent diffusion parameters and turbulent intensity parameters in the lake hydrodynamic model had little effect on the uncertainty of simulated results (less than 1% contribution). The findings were sufficiently significant to reduce the parameter uncertainties and calibration workload of the hydrodynamic model in large shallow lakes.
Editor Z. W. Kundzewicz; Associate editor S. Grimaldi 相似文献
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Daily river inflow time series are highly valuable for water resources and water environment management of large lakes. However, the availability of continuous inflow data for large lakes is still relatively limited, especially for large lakes situated within humid plain regions with tens or even hundreds of tributaries. In this study, we choose the fifth largest freshwater Lake Chaohu in China as our study area to introduce a new approach to reconstruct historical daily inflows at ungauged subcatchments of large lakes. This approach makes use of water level, lake surface rainfall, evaporation from the lake, and catchment rainfall observations. Rainfall–runoff relationship at a reference catchment was analysed to select rainfall input and estimate run‐off coefficient firstly, and the run‐off coefficient was then transferred to ungauged subcatchments to initially estimate daily inflows. Run‐off coefficient was scaled to adjust daily inflows at ungauged subcatchments according to water balance of the lake. This approach was evaluated using sparsely measured inflows at eight subcatchments of Lake Chaohu and compared with the commonly used drainage area ratio method. Results suggest that the inflow time series reconstructed from this approach consistent well to corresponding observations, with mean R2 and Nash–Sutcliffe efficiency values of 0.69 and 0.6, respectively. This approach outperforms drainage area ratio method in terms of mean R2 and Nash–Sutcliffe efficiency values. Accuracy of this approach holds well when the number of water‐level station being used decreased from four to one. 相似文献
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Using stable isotopes 18O and 2H of lake water and biogeochemical analysis to identify factors affecting water quality in four estuarine Amazonian shallow lakes 
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下载免费PDF全文 Stable isotopes analyses of oxygen and hydrogen of lake water were used to estimate the effect of evaporation (E) on the water quality of four shallow lakes in the Amapá State coast—Amazon/Brazil. These lakes, with different size and hydrologic conditions, were sampled during the course of the 2015/2016 El‐Niño (record‐breaking warming/drought in the Amazon rainforest). Hydrometeorological and water quality parameters were simultaneously performed to the isotopic sampling. The results showed that the evaporation process and the water quality can be explained by climate season and distances from the Atlantic Ocean. Lake evaporation losses ranged from ≈0–22% during the wet season in April/2016 and ≈35.7% during the dry season in November/2015. As expected, the evaporation of lake water was greater during the dry season, but it was higher for lakes farther away from the Atlantic Ocean compared with more coastal lakes due to tidal preponderance and the influence of major river channels. The more inland estuarine lakes showed a lower level of salinity (0.00–0.03 ppt) compared with those closer to the Atlantic Ocean (0.01–0.08 ppt). The El Niño phenomenon, with a lower precipitation in the Amazon basin, may initiate salinization of lakes closer to the Atlantic Ocean. Furthermore, strong mean seasonal variations of evaporation (0.06 ≤ E ≤ 0.22) and other hydrologic parameters were observed (precipitation, water temperature, and water depth), with significant effects on the water quality such as salinity, dissolved oxygen, chlorophyll (p < .05). We conclude that the occurrence of the extreme climatic events can disrupt the biogeochemical and hydrological balance of these aquatic ecosystems and salinization of lakes closer to the Atlantic Ocean. 相似文献
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1860年以来博斯腾湖碳沉积过程演变 总被引：1，自引：1，他引：0
选取博斯腾湖3个不同点位岩芯，在210Pb和137Cs年代序列基础上，利用沉积物中的各理化指标，分析了该湖碳沉积的时空变化特征，结合各指标的相关性、沉积速率、C/N、同位素特征等，探讨了该湖1860年以来碳沉积环境的变化过程，为干旱区湖泊碳埋藏研究提供了依据.结果表明：1860-1910年，沉积速率相对较小，受人类活动影响较小，磁化率、中值粒径、总无机碳（TIC）较为稳定，总有机碳（TOC）含量相对较低，此时该湖有较多陆源有机质的输入；1910-1950年，湖泊西部浅水域沉积速率明显高于东部深水区，西北湖区水域有大量外源物质的输入，而湖泊初级生产力较低，内源贡献相对较小；1950-1980年，全湖TOC、TIC含量均呈现升高的趋势，尤其是西北近黄水沟水域升高最快，湖泊内源贡献在增加，陆源组分的输入相对前一阶段要少；1980-2002年，沉积速率快速升高，尤其湖泊东部水域最为明显，TOC含量均呈现升高的趋势，湖泊西部水域初级生产力要高于东部深水区，湖面蒸发较强，气候比较温暖；2002年以来，全湖沉积速率相对较高，外源有机质贡献较小.过去150年博斯腾湖沉积物碳累积速率整体上呈现出升高的趋势，尤其是近50年来快速升高，东部湖区碳累积速率比西部湖区高. 相似文献
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从沉积物特征谈太湖的演变 总被引：3，自引：5，他引：3
通过太湖湖底淤泥层中的微体古生物及其物理化学分析,在西太潮W1孔发现多门类海相化石。海相化石出现的时间约在1100—5000aB.P.之间。据此提出西太湖在全新世期间曾遭受海侵,因而支持了太湖形成于泻湖的说法,同时,还提出海水进入太湖的时间,比以往学者推测的早2000多年。 相似文献
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Humid Little Ice Age in arid central Asia documented by Bosten Lake, Xinjiang, China 总被引：15，自引：0，他引：15
J. A. Holmes 《中国科学D辑(英文版)》2006,49(12):1280-1290
Short sediment cores retrieved from Bosten Lake, the largest inland freshwater lake in China, were used to explore humidity and precipitation variations in arid central Asia during the past millennium. The chronology of the cores was established using 137Cs, 210Pb and AMS 14C dating re- sults. Multi-proxy high-resolution analysis, including pollen ratios of Artemisia and Chenopodiaceae (A/C), carbonate content and grain size, indicates that the climate during the past millennium can be divided into three stages: a dry climate between 1000―1500 AD, a humid climate during the Little Ice Age (LIA) (c. 1500―1900 AD), and a warm dry period after 1900 AD. On centennial timescales, the climate change in northwestern China during the past 1000 years is characterized by oscillations between warm-dry and cold-humid climate conditions. All the proxies changed significantly and indi- cate increased precipitation during the LIA, including increased pollen A/C ratios and pollen concen- trations, decreased carbonate content and increased grain size. The humid period during the LIA re- corded by the Bosten Lake sediments is representative of arid central Asia and is supported by nu- merous records from other sites. During the LIA, the water runoff into the Keriya River and Tarim River in the Tarim Basin increased, while the ice accumulation in the Guliya ice core increased. Additionally, the lake levels of the Aral and Caspian Sea also rose, while tree-ring analysis indicates that precipita- tion increased. We hypothesize that both the lower temperature within China and the negative anomalies of North Atlantic Oscillation (NAO) during this period may have contributed to the humid climate within this area during LIA. 相似文献
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U. Saravana Kumar Noble Jacob S. V. Navada S. M. Rao Rm. P. Nachiappan Bhishm Kumar J. S. R. Murthy 《水文研究》2001,15(3):425-439
Environmental isotopes (δ18O, δD and 3H) were used to understand the hydrodynamics of Lake Naini in the State of Uttar Pradesh, India. The data was correlated with the in situ physico‐chemical parameters, namely temperature, electrical conductivity and dissolved oxygen. The analysis of the data shows that Lake Naini is a warm monomictic lake [i.e. in a year, the lake is stratified during the summer months (March/April to October/November) and well mixed during the remaining months]. The presence of a centrally submerged ridge inhibits the mixing of deeper waters of the lake's two sub‐basins, and they exhibit differential behaviour. The rates of change of isotopic composition of hypolimnion and epilimnion waters of the lake indicate that the water retention time of the lake is very short, and the two have independent inflow components. A few groundwater inflow points to the lake are inferred along the existing fractures, fault planes and dykes. In addition to poor vertical mixing of the lake due to the temperature‐induced seasonal stratification, the lake also shows poor horizontal mixing at certain locations of the lake. The lake–groundwater system appears to be a flow‐through type. Also, a tritium and water‐balance model was developed to estimate the water retention time of well‐mixed and hydrologically steady state lakes. The model assumes a piston flow of groundwater contributing to the lake. The developed model was verified for (a) Finger Lakes, New York; (b) Lake Neusiedlersee, Austria; and (c) Blue Lake, Australia based on literature data. The predicted water retention times of the lakes were close to those reported or calculated from the hydrological parameters given in the references. On application of this model to Lake Naini, a water retention time of ～2 years and age of groundwater contributing to the lake ～14 years is obtained. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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新疆博斯腾湖水盐平衡及水环境预测 总被引：3，自引：1，他引：2
本文通过综合整理、筛选、分析焉耆盆地1960-2003年历年逐月水文、气象、水土开发、社会经济等资料,并结合遥感影像数据,应用水盐平衡模型,模拟分析该期问博斯腾湖的水盐平衡状况,并以此为基础,结合焉耆盆地近期规划设置了两个情景方案进行模拟,对博湖未来40多年的水环境做出预测分析.结果表明。尽管近年博湖年均脱盐量达30.6×104t/a,但仍然必须使盆地进入湖区的淡水量增加、盐量减少才能降低博湖的水矿化度.盆地内近期工程项目实施后(情景B),博湖大湖区水矿化度波动于0.84-1.38g/L之间,其水矿化度有望调控到1.00g/L以下.据模拟,预测期的第37年(2040年),其水矿化度才可降至1.00g/L.孔雀河水质难于恢复到原状态,但是在保证博湖水环境改善的前提下,其水矿化度可调控到0.60g/L以下.由情景B的预测分析表明,焉耆盆地近期规划实施的工程项目对博湖的水环境是有利的,博湖水环境向良性循环发展. 相似文献
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枝角类作为淡水湖泊生态系统中的初级消费者之一,对生存环境的改变极为敏感.本文分析了太湖西、中和东部等湖区的钻孔沉积物、表层沉积物以及春夏秋季活体枝角类的组成与丰度.结果表明:活体枝角类组成以象鼻溞(Bosmina spp.)为优势种,秋季枝角类属种数量最多.太湖不同生态型湖区表层沉积物枝角类组成均以象鼻溞为优势种,其中西部与中心湖区的枝角类组成与丰度较为相似,种类单一,枝角类绝对丰度高;东部湖区枝角类属种较为丰富,绝对丰度低,优势种由浮游种象鼻溞以及沿岸种圆形盘肠溞(Chydorus sphaericus sl)和西方笔纹溞(Graptoleberis testudinaria)等种属构成.百年以来,太湖枝角类组成与丰度随着营养水平增加而改变,富营养指示种(Bosmina longirostris)丰度的增加与贫营养指示种(Bosmina longispina)丰度的下降,响应了湖区生态环境的演变过程.1970s末期,太湖西部与中心湖区在进入富营养化阶段,枝角类组成单一,象鼻溞占有绝对优势,与东部湖区相比,沿岸种、底栖种稀少.东部湖区在1960s以后,枝角类属种数量增加,但丰度下降,响应了1960s以来该区域营养水平提高、沉水植被生物量增加以及沼泽化加剧的环境过程. 相似文献
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东太湖养殖渔业可持续发展的思考 总被引：13，自引：4，他引：13
东太湖是长江中下游典型草型湖泊，渔业资源丰富，水质良好，具有渔业、泄洪、供水等重要功能，作为我国最早开始网围养殖等养殖业开发的湖泊之一，在促进我国湖泊渔业的发展等方面起到了重要作用，但是养殖渔业的快速发展也带来了一定的负面影响，影响了湖泊渔业等的持续发展，本文以东太湖作为我国浅水湖泊的典型代表，在分析其主要资源及环境特征的基础上，重点分析网围养殖与环境之间的关系，剖析养殖渔业存在的主要问题，提出了相应的湖泊渔业养殖承载力资源环境模型，并就未来湖泊渔业发展提出建议。 相似文献
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《水文科学杂志》2013,58(1)
Abstract Abstract MODerate-resolution Imaging Spectroradiometer (MODIS) is a new generation remote sensing (RS) sensor and its applications in hydrology and water resources have attracted much attention. To overcome the problems of slow response in flood disaster monitoring based on traditional RS techniques in China, the Flood Disaster Monitoring and Assessing System (FDMAS), based on MODIS and a Geographic Information System (GIS), was designed and applied to Dongting Lake, Hunan Province, China. The storage curve of Dongting Lake for 1995 was obtained using 1:10 000 topographic map data and then a relationship between water level at the Chenglingji hydrological station and lake area was derived. A new relationship between water level and lake area was obtained by processing MODIS images of Dongting Lake from April 2002 to April 2003 and the influence of lake area variation on water level was analysed with the 1996 flood data. It was found that the water level reduction reached 0.64 m for the 1996 flood if the original lake area curve was replaced with the area curve of 2002. This illustrates that the flood water level has been considerably reduced as a result of the increased area of Dongting Lake since the Chinese Central Government’s ?return land to lake? policy took effect in 1998. 相似文献
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长江中下游浅水湖泊富营养化发生机制与控制途径初探 总被引：191，自引：22，他引：169
长江中下游地区是我国淡水湖泊比较集中的地区。该地区绝大多数湖泊为浅水湖泊,所有的城郊湖泊都已经富营养化,其他湖泊的营养状况均为中营养－富营养,处于富营养化的发展中,这些湖泊富营养化的原因同流域上的人类活动有很大的关系。一方面,工业,农业和城市生活污水正源源不断地向湖泊中排放。另一方面,人类通过湖泊围垦、湖岸忖砌,水产养殖等破坏自然生态环境,减少营养盐输出途径。国际上对于浅水湖泊富营养化治理的经验表明,即使流域上的外源污染排放降到历史最低点,湖泊富营养化问题依然突出,其原因与浅水湖泊底泥所造成的内源污染有关。动力作用导致底泥悬浮,,影响底泥中营养盐的释放,也影响水下光照和初级生产力。控制浅水湖泊富营养化,除了进行外源性营养盐控制之外,还必须进行湖内内源营养盐的治理。治理内源营养盐的有效途径是恢复水生植被,控制底泥动力悬浮与营养盐释放。而要进行水生植被恢复,必须进行湖泊生态系统退化机制及生态修复的实验研究。 相似文献