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1.
湖泊水位是评估湖泊水量变化的重要指标。本文以洪泽湖、高邮湖及洞庭湖为研究对象,利用集中度的概率密度函数方法(CPDF)来提高Jason-2测高数据精度,分析了降水量与各个湖泊水位变化的相关性,并基于实测水位数据对比评价了Jason-2测高卫星原始GDR数据和CPDF方法处理后的卫星数据的精度。结果表明:①Jason-2原始GDR数据点的分布存在疏密之分,大部分数据分布相对集中,且有一定的周期变化,但评价结果显示精度较差,故原始GDR数据不能直接用于湖泊水位监测;②CPDF方法可以极大提高测高卫星的水位数据精度,洪泽湖与高邮湖的均方根误差分别由1.92 m与1.74 m减少到了0.32 m和0.36 m,相关系数由0.28和0.04提高到了0.85和0.72。对于南北宽度较窄且日水位变化较大的湖泊(如洞庭湖),CPDF方法提高原始GDR结果的精度有限;③洞庭湖降水与水位相关性最强,高邮湖次之,而洪泽湖降水与水位成不显著的负相关,是洪泽湖水利工程对于水位的调节导致了这一结果。本研究对于利用测高卫星获得湖泊水位值,进而对湖泊进行动态监控,特别是在填补资料匮乏地区湖泊水位数据方面具有重要意义。  相似文献   

2.
The rapid shrinkage of the surface area reflects the long-term deficit water budget of Qinghai Lake. Study of the yearly hydrology and meteorology in the lake catchment basin and the hydrologic factors as well as water budget led to the conclusion that evaporation exceeding the water input resulted in the drop of lake level, thai the obvious decrease of runoff to the lake and precipitation on the catchment accelerated the falling of lake level before 1987. and that increase of about 6.7% in rainfall on the whole basin will balance the lake's water budget.  相似文献   

3.
In recent years, sedimentation conditions in Dongting Lake have varied greatly because of significant changes in runoff and sediment load in the Changjiang (Yangtze) River following the construction of Three Gorges Dam. The topography of the lake bottom has changed rapidly because of the intense exchange of water and sediment between the lake and the Changjiang River. However, time series information on lake-bottom topographic change is lacking. In this study, we introduced a method that combines remote sensing data and in situ water level data to extract a record of Dongting Lake bottom topography from 2003 to 2011. Multi-temporal lake land/water boundaries were extracted from MODIS images using the linear spectral mixture model method. The elevation of water/land boundary points were calculated using water level data and spatial interpolation techniques. Digital elevation models of Dongting Lake bottom topography in different periods were then constructed with the multiple heighted waterlines. The mean root-mean-square error of the linear spectral mixture model was 0.036, and the mean predicted error for elevation interpolation was -0.19 m. Compared with field measurement data and sediment load data, the method has proven to be most applicable. The results show that the topography of the bottom of Dongting Lake has exhibited uneven erosion and deposition in terms of time and space over the last nine years. Moreover, lake-bottom topography has undergone a slight erosion trend within this period, with 58.2% and 41.8% of the lake-bottom area being eroded and deposited, respectively.  相似文献   

4.
STUDIESONWATERSTAGEFLUCTUATIONOFYAMZHOLAKEINXIZANGLiuTianchou(刘天仇)(TibetanBureauofWaterResourceandHydrologicalSurvey,Lhasa350...  相似文献   

5.
According to scientific evidence in general, the disappearance of the Tatras tarns as a result of external geomorphological processes has been accepted since the long term analyses of lake sediments and peat bogs, geomorphological mapping, geophysical measurements(– all indirect methods). It is paradoxical that the direct cartographic evidence of such changes has not existed until now. In this paper, we evaluate shore line changes of the small mountain glacial lake in the High Tatras-Litworowy Staw lake using a multitemporal analysis of a series of historical orthophotomaps and a historical map. Over the last 100 years, the tarn has lost 46.4% of open water level area. Significant visual changes were caused by vegetation growth of Carex species(sedges) on the water's surface. The accumulation of fine sediments and dead plant residues in the tarn basin create suitable conditions for this process, all together causing the tarn to become more shallow.  相似文献   

6.
CLIMATICTRENDINDICATEDBYVARIATIONSOFGLACIERSANDLAKESINTHETIANSHANMOUNTAINS¥HuRuji;YangChuande;MaHong;JiangFengqing(XinjiangIn...  相似文献   

7.
利用Jason-1数据监测呼伦湖水位变化   总被引:8,自引:2,他引:6  
卫星测高为内陆水域水位变化的实时和连续监测提供了一种高效的技术工具.但是这种应用受到数据点覆盖稀疏的限制。利用Jason-13年(2002-2004)GDRs测高数据作简单的数据编辑,并进行必要的地球物理改正.最后得到内蒙古地区呼伦湖水位变化的时间序列。呼伦湖地区由于近年来持续干旱,水位呈现明显的下降趋势.年平均下降约0.3~0.5m。在一般的内陆水域.水位变化主要取决于降雨量和蒸发量,所以,根据卫星测高所得的水位变化信息.可以为区域气候变化的研究提供一种全新的技术与方法。  相似文献   

8.
在全球变化背景下,湖泊水文的动态变化不仅是评估和预测气候与环境变化的重要指示剂,同时对社会可持续发展、水资源的开发与利用、生态文明建设等产生重要影响。湖泊水文的动态变化受到湖滨及湖底地形的控制,数字高程模型(DEM)成为湖泊水文研究的重要数据源。随着遥测技术的发展,高分辨率、区域/全球大尺度DEM数据的获取手段快速发展、数据源不断丰富,DEM对推动湖泊水文动态研究进展起到了关键作用。本文首先基于Web of Science平台对DEM在湖泊水文动态研究中的相关文献进行了分析,阐述了该主题现有研究在发文时间、发文数量增减态势、研究区域与热点地区、文献所涉及的DEM数据等方面的特点。接着,围绕着DEM在湖泊水文动态的研究中4个主要方向:湖泊水域变化、湖泊水位变化、湖泊水量变化、湖泊水文灾害情势,重点总结:DEM与其他遥感观测平台、实地观测及模型模拟等多源数据的融合策略,数字地形分析与水文学分析、遥感影像分析等方法的集成策略,以及DEM数据不确定性等对湖泊水文变化研究的影响。最后,本文论述了目前DEM在湖泊水文研究中存在的关键问题,并结合技术发展趋势和研究热点问题,提出了可能的解决路径和未来的研究前景。  相似文献   

9.
In this paper,we introduced parameterizations of the salinity effects(on heat capacity,thermal conductivity,freezing point and saturated vapor pressure) in a lake scheme integrated in the Weather Research and Forecasting model coupled with the Community Land Model(WRF-CLM). This was done to improve temperature simulation over and in a saline lake and to test the contributions of salinity effects on various water properties via sensitivity experiments. The modified lake scheme consists of the lake module in the CLM model,which is the land component of the WRF-CLM model. The Great Salt Lake(GSL) in the USA was selected as the study area. The simulation was performed from September 3,2001 to September 30,2002. Our results show that the modif ied WRF-CLM model that includes the lake scheme considering salinity effects can reasonably simulate temperature over and in the GSL. This model had much greater accuracy than neglecting salinity effects,particularly in a very cold event when that effect alters the freezing point. The salinity effect on saturated vapor pressure can reduce latent heat flux over the lake and make it slightly warmer. The salinity effect on heat capacity can also make lake temperature prone to changes. However,the salinity effect on thermal conductivity was found insignificant in our simulations.  相似文献   

10.
Water quality assessment of lakes is important to determine functional zones of water use. Considering the fuzziness during the partitioning process for lake water quality in an arid area, a multiplex model of fuzzy clustering with pattern recognition was developed by integrating transitive closure method, ISODATA algorithm in fuzzy clustering and fuzzy pattern recognition. The model was applied to partition the Ulansuhai Lake, a typical shallow lake in arid climate zone in the west part of Inner Mongolia, China and grade the condition of water quality divisions. The results showed that the partition well matched the real conditions of the lake, and the method has been proved accurate in the application.  相似文献   

11.
湖泊富营养化是当前全球范围内最为典型且严重的水环境问题之一,但过去偏重营养盐向湖泊的点源和面源输入评价,常常忽视地表水-地下水相互作用在湖泊水质形成与演化中的作用。总结了地下水-湖水相互作用模式,重点评述了地下水排泄过程对湖泊水文与水质影响的研究进展,对比了渗流仪测量、水量平衡、氡质量平衡、温度示踪、数值模拟等量化方法的优劣性与适用性,探讨了地下水向湖泊排泄的时空变异性、地下水-湖水界面氮磷的迁移转化等难点问题的研究现状,提出该领域未来研究方向主要包括:综合运用多种技术方法,表征湖底地下水排泄的时空变异性;揭示界面水文生物地球化学过程,量化地下水向湖泊排泄氮磷负荷;评估强烈人类活动改造对地下水-湖水相互作用的影响。   相似文献   

12.
Present-day conditions of the Lake Kenon ecosystem are determined by a combination of natural and anthropogenic factors.We have estimated the effects of a complex of factors on the condition of the abiotic environment and on specific biological components in the lake ecosystem.Change in biogenic load has caused an increase in the role of phytoplankton in the general balance of organic matter during the high-water period.Charophytes are the main dominants of bottom vegetation.Anthropogenic load has caused a decrease in both fish species and fish capacity.The lake application as a water reservoir-cooler has influenced the average annual water mineralization(from 420 mg/L to 530.0 mg/L with a maximum 654 mg/L in 1993) and fluctuations in its hydrochemical composition.The present composition of the lake is sulfate-hydrocarbonate-chloride calcium-sodic-magnesium in character.SO 4 – content is twice as much as the maximum permissible concentration in fishery waters.Water drainage from an ash disposal area to the lake has caused an increase in chemical-element concentrations including the heavy metals.Hg concentration in Perca fluviatilis muscles is 0.5 μg/g dry wt.Thus,understanding directions in the ecosystem of the water reservoir-cooler under changing hydrological conditions will let us forecast the consequences of new combined heat and power plant operation.  相似文献   

13.
在建立长时间序列地下水数值模型时,根据数据精度建立前后连贯的不同模型,前后模型的模拟期可重复,不但可提高模拟效果,又可缩短模型运行时间。采用试估—校正法进行识别和检验地下水数值模型时,水文地质参数、地下水流场、地下水均衡变化和地下水水位动态变化的拟合情况要符合研究区实际的水文地质条件。用地下水数值模型评价深层地下水资源时,需考虑研究区不同区域深层地下水不同开发利用程度,开发利用程度低的区域要考虑可动用的深层地下水释水量。  相似文献   

14.
Lake monitoring by remote sensing is of significant importance to understanding the lake and ambient ecological and environmental processes. In particular, whether lake water storage variation could predict lake surfacial temperature or vice versa has long fascinated the research community, in that it would greatly benefit the monitoring missions and scientific interpretation of the lake change processes. This study attempted to remotely detect the dynamics of the Aral Sea and pursue the relationships between varying lake water storage attributes and surface water temperature by using MODIS LST(Moderate-resolution Imaging Spectroradiometer Land Surface Temperature) 8-day composite products, satellite altimeter data, and actual meteorological measurements. Their associations with lake Surface Water Temperatures(SWT) were then analyzed. Results showed the lake water surface areas and elevations of the North Aral Sea tended to increasing trend from 2001(2793.0 km~2, 13.6 m) to 2015(6997.8 km~2, 15.9 m), while those of the South Aral Sea showed a decreasing trend during 2001(20 434.6 km~2, 3.9 m) and 2015(3256.1 km~2, 0.9 m). In addition, the annual daytime and nighttime lake SWT both decreased in the North Aral Sea, while only the daytime SWT in the South Aral Sea exhibited an increase, indicating a rising deviation of diurnal temperatures in the South Aral Sea during the past 15 yr. Moreover, a lower correlation was found between variations in the daytime SWT and storage capacity in the South Aral Sea(R~2 = 0.33; P 0.05), no fair correlations were tested between lake water storage and daytime SWT in the North Aral Sea nor between lake water storage and nighttime SWT in either part of the sea. These results implied that climate change, if any at least during the research period, has no significant effects on lake dynamics over the two sectors of the Aral Sea with anthropogenic disturbances. However, climate change and human activities may overlap to explain complex consequences in the lake storage variations. Our results may provide a reference for monitoring the spatiotemporal variations of lakes, increasing understanding of the lake water storage changes in relation to the lake SWT, which may benefit the ecological management of the Aral Sea region, in the effort to face the likely threats from climate change and human activities to the region.  相似文献   

15.
以1972、1989、1996、2006、2017年5个不同时段的Landsat MSS/TM/ETM+/OLI遥感影像数据、数字高程模型(DEM)数据和气象数据为数据源,通过计算机自动提取与人工目视解译相结合的方法获取南阿尔泰山中部地区各时段的冰湖信息,利用GIS空间分析方法对该地区的冰湖面积进行统计,并分析研究区冰湖在不同规模、不同坡度、不同海拔状态下的时空变化特征。结果表明:①近45年来南阿尔泰山中部地区的冰湖面积呈"先减后增"趋势。1972-1996年研究区的冰湖面积从411.14 km2减少至400.83 km2,共减少了10.31 km2,减少速率为0.43 km2/a。从1996-2017年冰湖面积增加了15.42 km2;增长率为0.514 km2/a。②研究区冰湖分布主要集中在海拔低于2 200 m、坡度小于25°的区域,不同海拔区间和不同坡度区间的冰湖面积均呈"先减后增"趋势。③结合气温、降水、冰川面积以及冰储量变化数据分析发现,南阿尔泰山中部地区冰湖对气候变化具有明显的响应。温度、降水量及冰川融水是影响冰湖面积变化的主要因素;且这三者之间存在一种平衡关系,即温度升高冰川消融速度加快,从而对冰湖的收支平衡产生直接影响。当冰湖的补给量(即冰川融水和降水量之和)大于由温度升高引起的蒸发量时,冰湖面积会呈增长趋势;反之亦然。1970-1980年整个阿勒泰地区年代际降水量减少了19.28 mm,温度上升了0.25℃,因此1972-1989年研究区冰湖的蒸发水量大于补给水量,导致该时段冰湖面积呈退缩态势。1989-1996年该区降水量增加了19.67%,温度升高了0.62℃,但是增加的降水量却无法弥补由温度升高引起的冰湖蒸发量,因此1989-1996年研究区冰湖面积仍处于退缩状态。1996-2017年由于温度和降水量大幅增加导致冰湖面积呈不断增长趋势。   相似文献   

16.
The evolution of the inland lakes in arid and semi-arid zones is accorded with the climatic fluctuation. The humid climate is in harmony with the higher water level and greater lake water quantity budget while arid climate is in correspondence with the lower water level and little water budget. Based on the analysis of the lake fluctuation and lake budget change, with the aid of the data of geom'orphology, palynology, sedimentology and chronology, It is found that the climate experienced a warm and humid period during 7000-3500 yr. B. P. and showed a drying and warming trend in the last century in the Central Asia.  相似文献   

17.
Zonag, Kusai, Hedin Noel and Yanhu Lakes are independent inland lakes in the Hoh Xil region on the Qinghai-Tibet Plateau. In September2011, Zonag Lake burst after the water level had increased for many years. Floods flowed through Kusai and Hedin Noel Lakes into Yanhu Lake; since then, the four small endorheic catchments merged into one larger catchment. This hydrological process caused the rapid shrinkage of Zonag Lake and continuous expansion of Yanhu Lake. In this study,based on satellite images, meteorological data and field investigations, we examined the dynamic changes in the four lakes and analyzed the influencing factors. The results showed that before 2011, the trends in the four lake areas were similar and displayed several stages. The change in the area of Zonag Lake corresponded well to the change in annual precipitation(AP), but the magnitude of the change was less than that of a non-glacier-fed lake. Although increased precipitation was the dominant factor that caused Zonag Lake to expand, increased glacier melting and permafrost thawing due to climate warming also had significant effects. After the 2011 outburst of Zonag Lake, due to the increasing AP and accelerating glacier melting, the increases in water volume of the three lakes were absorbed by Yanhu Lake, and Yanhu Lake expanded considerably. According to the rapid growth rates in water level and lake area, Yanhu Lake is likely to burst in 1-2 years.  相似文献   

18.
东平湖新湖分区运用的探讨   总被引:3,自引:0,他引:3       下载免费PDF全文
东平湖新湖区面积、库容较大,但多数情况下分滞洪水量较小.而分滞一次洪水最小损失达25亿元以上,易造成小水大灾.东平湖新、老湖二级运用已有成功经验.依据新湖的运用水位、淹没损失分析,结合南水北调输水工程,提出新湖分区运用的基本设想;国民经济评价证明,新湖分区运用是可行的.  相似文献   

19.
Extreme seasonal water level fluctuations characterize natural floodplain lakes in monsoon regions, which are crucial for ensuring lake water security, including flood prevention water supply and health of aquatic ecosystem. In order to achieve this goal, we established a hydrological regime assessment method based on a set of hydrological indicators for lakes with heavy seasonal water level fluctuations. The results suggest that time-sensitive hydrological indicators and specific time scales for various water security aspects must be considered. We discovered that it is more practical and meaningful to combine the water level classification derived from statistical analyses with characteristic hydrological values linked to water security. The case study of Poyang Lake results show that there are no discernable trends of Poyang Lake water regime status over the last 35 years, and the two periods of poor status are in accordance with climate variation in the lake basin area. Scholars and policy makers should focus on both floods and droughts, which are the main water security problems for Poyang Lake. It is hoped that this multi-scale and multi-element hydrological regime assessment method will provide new guidelines and methods for other international scholars of river and lake water assessment.  相似文献   

20.
浮游植物物候能够反映浮游植物的生长变化与湖泊生态系统的变化,水温、营养盐浓度等因素对物候有重要影响。太湖富营养化程度较高,水温的影响作用日趋显著,物候与水温关系的研究对理解、控制和改善太湖生态系统具有重要意义。本研究利用2003—2018年MODIS遥感数据计算浮游植物物候指标和湖泊水表温度(Temperature of Water Surface,LSWT),通过分析太湖浮游植物物候时空变化特点探究了不同区域的物候特征,并结合LSWT揭示了浮游植物物候对LSWT变化的响应关系。结果表明:① 不同浮游植物物候指标具有不同空间分布特点,水华发生次数、峰值叶绿素a(Chla)浓度和水华总持续时间呈现由西部沿岸向湖心区递减的趋势;浮游植物生长开始时间和峰值Chla发生时间分布复杂但在沿岸区域相对较早;② 太湖可被划分为4种具有不同物候特征的区域,Ⅰ类区域主要位于贡湖湾、东部沿岸以及太湖中部开阔水域,该区Chla浓度范围为50~60 μg/L,且波动平缓,水华发生次数最少、开始最晚、持续时间最短;Ⅱ类区域主要分布于太湖西部沿岸,Chla浓度范围为50~90 μg/L且变化剧烈,该区水华发生次数最多、开始最早、持续时间最长;Ⅲ和Ⅳ类属于过渡区域,前者主要分布于梅梁湾、竺山湾及入湾口,后者主要位于南部沿岸以及太湖中部;③ 浮游植物物候对LSWT变化的响应受营养水平影响,当营养水平较高时,浮游植物的生长受LSWT的促进作用显著,LSWT年际变化的升高趋势对浮游植生长物候提前、生物量增加的影响明显,反之,则LSWT变化对浮游植物生长的影响减弱。  相似文献   

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