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1.
该文在查明区域水文地质条件、湖区地下水的类型、分布、埋藏条件、含水层及隔水层特征、岩性结构以及地下水的补给、径流、排泄条件的基础上,通过现场试验,确定了天然状态下湖区各含水层之间的水力联系、黄河侧渗补给量及湖区向小清河的排泄量,结合数值模拟,预测了湖区维持设计蓄水位21.5m时黄河的侧渗补给量、湖区向小清河的排泄量及湖区对周边地下水位的影响。结果表明,天然状态下,黄河侧渗补给量为748.23m~3/d,湖区向小清河排泄量大约为52.03m~3/d,黄河侧渗补给量远大于湖区向小清河的排泄量。数值模拟结果表明,湖区维持设计蓄水位21.5m时,不同水文年湖区接受的侧渗补给量均大于湖区的渗漏量,且对周围地下水位的影响不超过1.5m,因此,湖区维持设计蓄水位21.5m时可不考虑防渗措施。 相似文献
2.
研究库水位波动和降雨影响下滑坡的位移变形特征并分析其破坏机制，对了解三峡库区滑坡的演化过程具有重要意义。以奉节曾家棚滑坡为例，基于GPS地表监测位移分析了滑坡在不同特征库水位运行阶段的变化规律，结合灰色关联度模型确定了滑坡不同部位的变形在不同阶段的主要控制因素，借助GEO-Studio软件模拟了曾家棚滑坡在历史降雨和库水位波动耦合作用下的稳定性变化，并与定量分析结果进行了交叉检验。结果表明:曾家棚滑坡的运动状态随时间变化，从缓慢蠕变状态进入阶跃变形状态。平面上，中东部坡体与西部坡体相比，运动更加强烈；剖面上，前缘变形早且变形量大。曾家棚滑坡变形失稳过程为初期蓄水启动了曾家棚古滑坡，前缘首先发生变形；降雨作为中后期主控因素，和库水位波动联合作用共同诱发了滑坡多次阶跃变形，使滑坡前中后部形成贯通裂缝；最终由二十年一遇的暴雨诱发滑坡发生整体破坏。 相似文献
3.
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
4.
Digital terrain modelling using Corona and ALOS PRISM data to investigate the distal part of Imja Glacier, Khumbu Himal, Nepal 总被引：2，自引：2，他引：0
This study used Corona KH-4A and Advanced Land Observing Satellite (ALOS) PRISM images to generate digital terrain models (DTMs) of the distal part of Imja Glacier,where a few supraglacial ponds (～0.07 km 2) expanded into the large Imja Glacier Lake (Imja Tsho,～0.91 km 2) between 1964 and 2006.DTMs and subsequently derived topographical maps with contour intervals of 1 m were created from the high-resolution images (Corona in 1964 and ALOS in 2006) in the Leica Photogrammetric Suite (LPS) platform.The DTMs and topographic maps provided excellent representation of the elevation and micro-topography of the glacier surface,such as its supra-glacial ponds/lake,surface depressions,and moraine ridges,with an error of about +/-4 m (maximum).The DTMs produced from the Corona and ALOS PRISM images are suitable for use in studies of the surface change of glaciers.The topographical maps produced from the Corona data (1964) showed that part of the dead ice in the down-glacier area was even higher than the top of the lateral moraine ridges,while the glacier surface in the up-glacier area was noticeably lower than the moraine crests.This suggests more extensive melting of glacier ice in the up-glacier area before 1964.The average lowering of the glacier surface from 1964 to 2006 was 16.9 m for the dead-ice area west of the lake and 47.4 m for the glacier surface east of the lake;between 1964 and 2002,the lake surface lowered by 82.3 m.These figures represent average lowering rates of 0.4,1.1,and 2.2 m/year for the respective areas. 相似文献
5.
库岸滑坡体分布广泛,在库水位升降和降雨条件下极易失稳。三板溪水电站东岭信滑坡堆积体总方量2 000×104 m3,最大厚度150 m,2006年水电站蓄水后滑坡体开始出现大变形,每年雨季加剧。首先经野外地质勘察和十余年监测数据整理,探明了地质条件和变形规律;其次使用SEEP/W模块对不同库水位升降速率、2019年库水位结合实测降雨条件下的饱和-非饱和流进行模拟,并采用SLOPE/W分别计算不同时刻的稳定系数。分析认为东岭信为超深层滑坡,其变形过程深受库水位升降和降雨影响;滑坡体具有明显的滞水特征,渗流过程复杂;在库水位上升过程中稳定系数不断下降,而在库水位消落过程中稳定性逐渐增强;在库水位上升和强降雨量共同作用下稳定性下降很快,汛后10 d左右达到最低值,此时的稳定性最差。本研究可用于指导库水位升降和降雨条件下大型滑坡体稳定性评价。 相似文献
6.
LIU Wen-hui XIE Chang-wei ZHAO Lin WU Tong-hua WANG Wu ZHANG Yu-xin YANG Gui-qian ZHU Xiao-fan YUE Guang-yang 《山地科学学报》2019,(5)
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
7.
基于长时间序列MODIS数据的鄱阳湖湖面面积变化分析 总被引：1，自引：0，他引：1
湖泊是气候、水和生物地球化学循环的关键组分,遥感观测有助于获得湖泊面积变化及对环境的响应信息。本文基于长时间序列遥感观测提出了一种利用像元水淹没/陆地出露比例的湖面变化分析算法,并应用于鄱阳湖的湖面提取及变化分析。首先,用全年遥感数据合成获得当年最大湖面;然后,在此最大湖面范围内,识别出每景数据的水体和陆地状态;最后,统计一定时期内每个像元的水淹没比例,并据此分析湖泊的年际和季节变化特征。该算法的最大优势是克服了云的干扰,以及湖面快速变化造成的年际变化对比分析困难问题。算法应用于2000-2010年MODIS观测,分析结果表明,本算法检测出的湖面面积与鄱阳湖水文站水位观测资料非常一致;算法可以获得鄱阳湖湖面面积的显著季节变化信息;2000-2010年间,鄱阳湖湖面面积在丰水期未发现有规律的变化;在枯水期,2003年后湖面面积急剧减小。 相似文献
8.
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
9.
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10.
在库水位波动和降雨作用的共同影响下，库岸滑坡的变形规律往往更为复杂。以三峡库区麻柳林滑坡为例，基于野外调查、钻探编录、深部位移监测以及数值模拟等手段，分析了库水位波动和降雨作用下滑坡变形特征及演化规律。结果表明:麻柳林滑坡在粉质黏土层和块石层交界处发育一个次级滑带，目前该滑坡主要沿次级滑带运动，导致次级滑动的原因与坡体物质的差异性有关；Si(Sf)指标分析法揭示滑坡的滑带还未完全破坏，滑坡仍处于蠕变状态；根据三峡水库水位调度规律，将一个完整水文年划分为6个阶段，数值模拟结果表明滑坡在库水位缓慢下降阶段变形速率较小、在快速下降阶段和低水位阶段变形速率持续增大、在快速上升阶段和缓慢上升阶段以及高水位阶段变形速率则保持平稳。其中，降雨的直接影响和降雨导致库水位波动进而对滑坡变形造成的间接影响，使得麻柳林滑坡在低水位阶段的变形显著增加、稳定性最差，应加强该时段内滑坡的监测和预警。 相似文献
11.
（张本）（康星华）ＴＨＥＦＥＡＴＵＲＥＳＯＦＴＨＥＮＡＴＵＲＡＬＲＥＳＯＵＲＣＥＳＡＮＤＴＨＥＲＥＮＯＶＡＴＩＯＮＳＴＲＡＴＥＧＹＯＦＰＯＹＡＮＧＬＡＫＥ￥ＺｈａｎｇＢｅｎＫａｎｇＸｉｎｇｈｕａ（ＨａｉｎａｎＵｎｉｖｅｒｓｉｔｙ，Ｈａｉｋｏｕ５７００... 相似文献
12.
This study reports on the clean ice area and surface elevation changes of the Khersan and Merjikesh glaciers in the north of Iran between 1955 and 2010 based on several high to medium spatial resolution remote sensing data.The object-oriented classification technique has been applied to nine remote sensing images to estimate the debris-free areas.The satellite-based analysis revealed that the clean ice areas of Khersan and Merjikesh glaciers shrank since 2010 with an overall area decrease of about 45% and 60% respectively.It means that the dramatic proportions of 1955 glaciers surface area are covered with debris during the last five decades.Although the general trend is a clean ice area decrease,some advancement is observed over the period of 1997-2004.During 1987-1991 the maximum decrease in the clean ice area was observed.However,the clean ice area had steadily increased between 1997 and 2010.To quantify the elevation changes besides the debris-free change analysis,several Digital Elevation Models(DEMs) were extracted from aerial photo(1955),topographic map(1997),ASTER image(2002) and Worldview-2 image(2010) and after it a 3-D Coregistration and a linear relationship adjustments techniques were used to remove the systematic shifts and elevation dependent biases.Unlike the sinusoidal variation of our case studies which was inferred from planimetric analysis,the elevation change results revealed that the glacier surface lowering has occurred during 1955-2010 continuously without any thickening with the mean annual thinning of about 0.4 ± 0.04 m per year and 0.3 ± 0.026 m per year for Khersan and Merjikesh glaciers,respectively.The maximum thinning rate has been observed during 1997-2002(about 1.1 ± 0.09 per year and 0.96 ± 0.01 mper year,respectively),which was compatible partially with debris-free change analysis.The present result demonstrates that although in debris-covered glaciers clean ice area change analysis can illustrate the direction of changes(retreat or advance),due to the high uncertainty in glacier area delineation in such glaciers,it cannot reveal the actual glacier changes.Thus,both planimetric and volumetric change analyses are very critical to obtain accurate glacier variation results. 相似文献
13.
秦伯强 《中国海洋湖沼学报》1993,11(4):314-320
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
14.
STREAMFLOW CHARACTERISTICS OF THE EASTERN QINGHAI-XIZANG PLATEAU 总被引：1，自引：0，他引：1
The eastern Qinghai-Xizang (Tibet) Plateau is the headwater area for many large Asian rivers. Permafrost occurs above 4,200 m a.s.l. and glaciers occupy the summits and high valleys of the east-west trending mountain chains. Annual runoff generally increases with precipitation which is augmented southward by the rise in topography. Rainfall, snow melt, glacier melt and groundwater are the primary sources of stream flow, and the presence of permafrost enhances the flashiness of runoff response to rainfall and snowmelt events. Peak flows are concentrated between June and September. And winter is low flow season. Three types of runoff patterns may be distinguished according to their primary sources of water supply: snowmelt and rainfall, glacier melt and snowmelt, and groundwater. Large rivers generally drain more than one environments and their runoff regime reflects an integration of the various flow patterns on the plateau. 相似文献
15.
Yoshitaka Komatsu Hiroaki Kato Bo Zhu Tao Wang Fan Yang Randeep Rakwal Yuichi Onda 《山地科学学报》2018,15(4):738-751
Purple soil is highly susceptible for overland flow and surface erosion, therefore understanding surface runoff and soil erosion processes in the purple soil region are important to mitigate flooding and erosion hazards. Slope angle is an important parameter that affects the magnitude of runoff and thus surface erosion in hilly landscapes or bare land area. However, the effect of slope on runoff generation remains unclear in many different soils including Chinese purple soil. The aim of this study was to investigate the relationship between different slope gradients and surface runoff for bare-fallow purple soil, using 5 m × 1.5 m experimental plots under natural rainfall conditions. Four experimental plots(10°, 16°, 20° and 26°) were established in theYanting Agro-ecological Experimental Station of Chinese Academy of Science in central Sichuan Basin. The plot was equipped with water storage tank to monitor water level change. Field monitoring from July 1 to October 31, 2012 observed 42 rainfall events which produced surface runoff from the experimental plots. These water level changes were converted to runoff. The representative eight rainfall events were selected for further analysis, the relationship between slope and runoff coefficient were determined using ANOVA, F-test, and z-score analysis. The results indicated a strong correlation between rainfall and runoff in cumulative amount basis. The mean value of the measured runoff coefficient for four experimental plots was around 0.1. However, no statistically significant relationship was found between slope and runoff coefficient. We reviewed the relationship between slope and runoff in many previous studiesand calculated z-score to compare with our experimental results. The results of z-score analysis indicated that both positive and negative effects of slope on runoff coefficient were obtained, however a moderate gradient(16°-20° in this study) could be a threshold of runoff generation for many different soils including the Chinese purple soil. 相似文献
16.
2000-2013年青藏高原湖泊面积MODIS遥感监测分析 总被引：2，自引：0，他引：2
青藏高原上分布着大量的高原内陆湖泊群,该区域湖泊面积与区域及全球气候变化之间存在较强的耦合关系,遥感监测湖泊的分布和面积变化趋势,对分析区域自然生态环境具有重要意义。本研究将MOD09A1（地表反射率8天合成数据）进行逐月合成,提出了一种综合多种水体指数的青藏高原地区湖泊提取方法,并通过活动窗口、DEM和时间序列去噪等方法,消除山体阴影、冰雪等因素的干扰。最后,提取和合成了2000-2013年青藏高原逐年和逐月的湖泊范围,并选取色林错和卓乃湖2个典型湖泊与人工解译Landsat系列影像进行验证分析,其线性拟合度分别为0.99和0.97,从时空变化趋势上分析了青藏高原湖泊面积动态变化。结果表明：（1）2000-2013年,青藏高原地区湖泊范围整体上呈较显著的扩张趋势,湖泊总面积增加速率约为490.98 km2 a-1（R2约为0.96）;（2）1-12月份湖泊面积逐月变化率均大于0,表明青藏高原湖泊面积呈整体扩张,而非季节性扩张。除2-4月份外,其他月份增加速率均在400 km2 a-1以上（R2>0.79）,表现为稳定且持续扩张趋势。 相似文献
17.
Zelongnong Ravine, a branch ravine of Brahmaputra, is an old large glacier debris-flow ravine. Debris-flows with medium and/or
small scales occur almost every year; multiple super debris-flows have also broken out in history, and have caused destructive
disaster to local residents at the mouth of ravine and blocked Brahmaputra. The huge altitude difference and the steep slope
of the Zelongnong Ravine provide predominant energy conditions for the debris-flow. The drainage basin is located in the fast
uplifted area, where the complicated geologic structure, the cracked rock, and the frequent earthquake make the rocks experience
strong weathering, thus plenty of granular materials are available for the formation of debris-flows. Although this region
is located in the rain shadow area, the precipitation is concentrated and most is with high intensity. Also, the strong glacier
activity provides water source for debris-flow. According to literature reviews, most debris-flows in the ravine are induced
by rainstorms, and their scales are relatively small. However, when the melted water is overlaid, the large scale debris-flows
may occur. Parametric calculation such as the flow velocity and the runoff is conducted according to the monitoring data.
The result shows that large debris-flows can be aroused when the rainstorm and the melted water are combined well, but the
possibility of blocking off Brahmaputra is rare. The occurrence of the super debris-flows is closely related to the intense
glacier activity (e.g., glacier surge). They often result in destructive disasters and are hard to be prevented and cured
by engineering measures, due to the oversized scales. The hazard mitigation measures such as monitoring and prediction are
proposed. 相似文献
18.
冰川变化监测对生态灾害预防、区域水资源调控、气候变化研究等意义重大。利用冰川在雷达干涉影像上表现出失相干这一特性,选用1998年ERS 1/2与2018年 Sentinel-1A重轨单视复数SAR数据,通过相干系数取阈值的方法获取东帕米尔高原两个时期的冰川边界,以Landsat TM/OLI影像和全球陆地冰川空间监测计划发布的数据验证本文冰川边界提取的精度,从而分析冰川变化。结果表明：① 拟合研究区相干系数图上相干系数γ与对应像元个数的曲线关系,冰川区像元个数会在低相干区域积累形成一个小的波峰。曲线一阶导数变缓的点（冰川区向非冰川区过渡的转折点）即为所选阈值点,利用SAR相干系数取阈值法提取的冰川边界与光学遥感影像结合RGI6.0数据提取的验证冰川边界具有较好的一致性,SAR干涉相干系数提取冰川边界的方法是可行而有效的,ERS 1/2与Sentinel-1A提取的冰川总面积精度均在90%以上,而且SAR数据能够有效提取光学遥感影像难以识别的冰川表碛覆盖;② 1998年和2018年东帕米尔高原冰川总面积减少了318.59 km2,年平均变化速率为-15.93 km2/a,冰川退缩面积占冰川总面积的23%;③ 对大、中型规模冰川来说,表碛覆盖型冰川退缩较其他冰川明显;从坡向上来看,20年各个坡向冰川均有所退缩,其中东南坡冰川退缩最多,西坡冰川退缩最少;从海拔上来看,1998年冰川集中分布在4519~5421 m海拔区间内,2018年集中分布在4682~5320 m海拔区间内;在3325~5710 m海拔区间内冰川退缩明显,4915 m海拔附近达到退缩极大值。 相似文献
19.
INTRODUCTIONThedistingnishingc~teristicsofQinghaboe,thebiewstsalinelakeinCfuna,are:vastwaterm,higheleVation,closeddrinagbasinandattrativenaedland-scape.The~clakeleveldIDPsincethebegiwhngofthiscentwhascausedaseriesofenvironrnntalProblems(degenndionofghanggIaSSlandaIDunthelake,desertffica-tioninthebeacharea,aeOianerosionoftheeXposedlakebed,deCrainwaersuPPliesandincreaseinthewaterndnends).IncentalAsia,mostofthewell-knOWnlargelakes,includingla.kessuchasIssyk-kul(SeVaStyanvandSndmov,l… 相似文献
20.
《山地科学学报》2019,(12)
Land creation projects have been implemented in China to expand urban space in mountainous areas. In addition to the predictable settlement brought about by filling construction,varying degrees of land subsidence and engineering failures have a demonstrated relationship to groundwater level fluctuation induced by land creation engineering. In this work, we adopted a typical large-scale land creation project, Yan'an New City in Shaanxi province, West China, as our study area. Prior to conducting the main experiment,preliminary field investigation and groundwater level monitoring were conducted to determine the groundwater fluctuation trend induced by land creation engineering. Although a blind drainage system was implemented, the depth aspect of groundwater level changes after large-scale land creation still needed to be addressed. To study the degree of impact and the settlement mechanism induced by the rising groundwater level, we conducted a Water Immersion Test(WIT) in a typical land creation site for 107 days. The rising groundwater level was simulated by injecting water from the bottom of the filling foundation. During the WIT, the soil water content, surface subsidence, and internal settlement of soil at different depths were obtained. Surface subsidence development could be categorized into four stages during the water level increase. The second stage, which is defined as the point when the groundwater level rises to 10 m,marked the critical point in the process. Furthermore,it was ascertained that the local settlement in regions that were originally composed of steep slopes is larger than that in originally flat areas. In addition, ground cracks and sinkholes in the study area were inspected;and it was determined that they would become new channels that would accelerate water infiltration and exacerbate the settlement. Based on the results from our field investigation and testing, several suggestions are proposed for land creation projects to mitigate issues associated with construction-induced groundwater level rising. 相似文献