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1.
新疆阿勒泰地区2002-2011年地表水资源变化趋势   总被引:1,自引:0,他引:1  
在RS技术支持下,应用气象数据(主要为气温、降水)、基础地理数据及2002-2011年时间序列的Landsat TM、ETM+、MODIS/Terra+Aqua MCD43A4遥感影像产品,对阿勒泰地区地表水资源时空变化特征进行了分析,探索气象因素影响下阿尔泰山冰川积雪和地表水资源之间的相互作用。结果表明:在研究时段内,阿尔泰山6月2日的冰川积雪面积呈波动增加趋势,8月21日的冰川积雪面积则呈波动减少趋势。从景观格局的特征来看,随着夏季冰雪融水量增加,水资源量总体呈上升趋势,在研究时段内水域总面积增加了57.91 km2,增加面积主要来源于湖泊和水库,2011年的湖泊和水库面积分别为1 044.33 km2和196.27 km2,比2002年分别增加了16.67 km2和101.79 km2;沼泽湿地和坑塘湿地的面积变化呈一定的起伏,2002-2011年间面积分别减少了35.91 km2和24.27 km2,湖泊和水库的破碎度较低,沼泽湿地、河流和坑塘湿地的破碎度高,表明沼泽湿地、河流和坑塘湿地对气象因素变化较敏感。  相似文献   

2.
Glacier retreat is not only a symbol of temperature and precipitation change, but a dominating factor of glacial lake changes in alpine regions, which are of wide concern for high risk of potential outburst floods. Of all types of glacial lakes, moraine-dammed lakes may be the most dangerous to local residents in mountain regions. Thus, we monitored the dynamics of 12 moraine-dammed glacial lakes from 1974 to 2014 in the Poiqu River Basin of central west Himalayas, as well as their associated glaciers with a combination of remote sensing, topographic maps and digital elevation models (DEMs). Our results indicate that all monitored moraine-dammed glacial lakes have expanded by 7.46 km2 in total while the glaciers retreated by a total of 15.29 km2 correspondingly. Meteorological analysis indicates a warming and drying trend in the Nyalam region from 1974 to 2014, which accelerated glacier retreat and then augmented the supply of moraine-dammed glacial lakes from glacier melt. Lake volume and water depth changed from 1974 to 2014 which indicates that lakes Kangxico, Galongco, and Youmojanco have a high potential for outburst floods and in urgent need for continuous monitoring or artificial excavation to release water due to the quick increase in water depths and storage capacities. Lakes Jialongco and Cirenmaco, with outburst floods in 1981 and 2002, have a high potential risk for outburst floods because of rapid lake growth and steep slope gradients surrounding them.  相似文献   

3.
In arid regions of Central Asia, cyclicity in the humidification behavior of a region shows long-term trends of changes in the water levels of closed lakes. Thus, the last 10 years saw a decrease in the water level by several meters on one of the region’s largest lakes — Hulun Nur (PRC). For water level stabilization on the PRC’s territory, a package of measures is undertaken for a partial Hailar river flow transfer (in the upper reaches of the Argun’ river) to Lake Hulun Nur. It is obvious that the lake’s water level regime will experience substantial changes. This paper discusses a variety of consequences of the river flow transfer and different water management modes, and forecasts the lake’s possible level regime, the Argun’ river discharge and the ecological consequences of measures of this kind for the Russian part of the drainage basin.  相似文献   

4.
When using rift lakes as proxies for palaeoclimate it is essential to know if water level changes are of geological or climatic origin, and whether a reinterpretation of palaeo-lake levels derived from lithostratigraphic sequences is required. The saline, endorheic Lake Beseka is located in the tectonically active Main Ethiopian Rift. Despite the aridity of the rift valley the lake's surface area quadrupled from 11.1 km2 in 1973 to 39.5 km2 in 2002. We quantify the lake growth by means of a detailed bathymetric model and high-resolution satellite time series. We analyse the potential climatic, anthropogenic, and tectonic agents of Lake Beseka's growth. Multitemporal remote sensing data and meteorological records were compared with in-situ measurements of hydrochemical parameters and water depth to address the reason for the lake level rise. Our results suggest that Lake Beseka's expansion originates from an increased discharge of the hot springs. The combined analysis of satellite data and in-situ measurements proved to be a valid tool for the quantification of lake level changes and can help to detect the causes of these variations.  相似文献   

5.
Surface sediments, water samples and environmental data from 37 lakes, ponds and streams in Israel were analysed to determine the main variables controlling ostracod species distributions. Multivariate statistical analysis revealed that the greatest amounts of variation in the distribution of the ostracod taxa among the 37 water bodies were explained by the host water δD value (12.9%), water temperature (11.0%), mean January air temperature (10.5%), electrical conductivity (9.5%), and the Mg and NO3 concentrations (7.8 and 7.1%, ion concentrations as % of the anions or cations). A supplementary data set comprising ostracod species composition and electrical conductivity readings for 24 water bodies was available from previous research and was merged with the 37 samples data set to develop an ostracod-based transfer function for the reconstruction of electrical conductivities. A weighted averaging partial least squares regression (WA-PLS) provided the best results with a relatively high coefficient of determination (r 2) between measured and inferred electrical conductivity values of 0.73, a root mean square error of prediction of 0.13 (13.4% of gradient length) and a maximum bias of 0.24 (23.9% of gradient length), as assessed by leave-one-out cross-validation based on 56 water bodies. The application of the EC transfer function onto (sub)fossil ostracod assemblages from Holocene and early to mid Pleistocene lake sediments provided EC values consistent with other proxies and demonstrated that Quaternary ostracod assemblages from subaqueous sediments can now be used to trace the hydrological history of water bodies in the Near East. A better understanding of past hydrological conditions in response to the natural climate variability is crucial in regions that face restricted water resources and rising demands in times of rapid climate and environmental change.  相似文献   

6.
Lakes in China have undergone considerable environmental changes during the past 50 years, e.g. lake level, water area changes, as did in the past several thousands years. The enhanced human activities, such as land reclamation, application of chemical fertilizer, land use and cover, irrigation and industrialization in the catchment etc., have played an im-portant role on the recent decades’ changes of these lakes, although constrained to a great extent by the natural impact. Comparative study on variations of lake volume (water level, depth and area) in the eastern and western lake regions of China during 1950–2000 indicated that, lake volume in the eastern region had approximately undergone a two-stage change, i.e. a dramatic decrease from the 1950s to 1970s, and a continuous increase between the 1980s and 1990s; while, in the western region, lake volume had been decreasing nearly all the time. Further studies on some typical lakes concluded that, climatic change was a primary factor for the variations of lake volume during the past 50 years, although human activities showed important effect.  相似文献   

7.
利用历史图件、地形图及遥感数据监测塔里木河下游诸多湖泊水域面积并分析近一百多年的变化情况。根据湖泊水域及其变化,该区湖泊在100多年内变化过程可以分为3个时间段:① 20世纪60年代以前,该区水文条件较好,19世纪末20世纪初湖泊总面积超过2000 km2;20世纪60-70年代至20世纪末,随着水利设施的陆续兴建,湖泊水域缩小,甚至某些湖泊彻底干涸;21世纪随着塔里木河流域综合治理与下游生态输水工程的实施,该区水文条件有所好转,干涸多年的一些湖泊重新形成水域,2013年湖泊水域总面积达760 km2。② 根据湖盆成因及水域变化把该区湖泊分为:河道西侧的风成湖,河道网之间及东侧的河成湖及河道末端的构造湖等三类。③ 初步总结风成湖演变过程,发现该区风成湖与河成湖在形状、深度、水质、形成时间等方面有较大差异。④ 近代人为因素对湖泊水域变化的影响高于自然因素。  相似文献   

8.
Lakes in China have undergone considerable environmental changes during the past 50 years, e.g. lake level, water area changes, as did in the past several thousands years. The enhanced human activities, such as land reclamation, application of chemical fertilizer, land use and cover, irrigation and industrialization in the catchment etc., have played an important role on the recent decades' changes of these lakes, although constrained to a great extent by the natural impact. Comparative study on variations of lake volume (water level, depth and area) in the eastern and western lake regions of China during 1950-2000 indicated that, lake volume in the eastern region had approximately undergone a two-stage change, i.e. a dramatic decrease from the 1950s to 1970s, and a continuous increase between the 1980s and 1990s; while, in the western region, lake volume had been decreasing nearly all the time. Further studies on some typical lakes concluded that, climatic change was a primary factor for the variations of lake volume during the past 50 years, although human activities showed important effect.  相似文献   

9.
Lakes in China have undergone considerable environmental changes during the past 50 years, e.g. lake level, water area changes, as did in the past several thousands years.The enhanced human activities, such as land reclamation, application of chemical fertilizer,land use and cover, irrigation and industrialization in the catchment etc., have played an im-portant role on the recent decades' changes of these lakes, although constrained to a great extent by the natural impact. Comparative study on variations of lake volume (water level,depth and area) in the eastern and western lake regions of China during 1950-2000 indicated that, lake volume in the eastern region had approximately undergone a two-stage change, i.e.a dramatic decrease from the 1950s to 1970s, and a continuous increase between the 1980s and 1990s; while, in the western region, lake volume had been decreasing nearly all the time.Further studies on some typical lakes concluded that, climatic change was a primary factor for the variations of lake volume during the past 50 years, although human activities showed important effect.  相似文献   

10.
The Imja Glacier Lake (Imja Tsho) (1.03 km2 in 2007) is repeatedly cited as one of the most dangerous glacial lakes in the Himalaya with a glacial lake outburst flood (GLOF) claimed to be imminent. Knowledge of lake development and its dynamics, however, is limited and forecasts of a possible outburst are not scientifically based. Nevertheless, prospects for such a catastrophe are repeatedly exaggerated, attracting alarmist mass media coverage. The paper provides an assessment of the lake expansion rates from 1956 to 2007. Stage 1 (1956–1975), slowest: coalescence of several small supra-glacial ponds; Stage 2 (1975–1978), a short period of most rapid expansion; Stage 3 (1978–1997), slow: gradual expansion of single lake; and Stage 4 (1997–2007), renewed acceleration: mainly eastward expansion into the glacier surface. The lake's water level has fallen from 5041 m to 5004 m (1964–2006). The results show that there is no immediate danger of catastrophic outburst although the dynamics of up-glacier and down-valley lake expansion, fluctuation of lake water level, and dead-ice morphology changes should be continuously and comprehensively monitored. Alarmist prognostications based solely upon rapid areal expansion are counterproductive.  相似文献   

11.
Shallow lakes in semiarid regions experience frequent water level fluctuations. Each long-lasting episode of water-level lowering leaves behind abandoned littoral forms and deposits whose identification and mapping is hampered by their smooth relief. Given the difficulty of recognising these possible relict forms using traditional geomorphological techniques, two sources of information were employed in the present work: high resolution (1:15,000) aerial photographs and a digital terrain model (DTM) generated from LiDAR data. The improved definition of surface elevation enhanced the quality of geomorphological mapping as well as the accurate delineation of subtle geoforms. The method was applied to Gallocanta Lake, a highly fluctuating shallow lake 14 km2 in area and less than 3 m deep located in a mountainous semiarid area of NE Spain. As a result, a sequence of relict coastal features (RCF) with high lateral continuity has been identified around the lakebed. These include well-preserved spits with recurved hooks, counter-spits, bays closed by barrier islands, beach ridges, deltas and cliffs. The highly precise LiDAR-derived topographic maps suggest a much greater extension of the lacustrine environment during the Late Pleistocene, reaching at least 51 km2 of water surface and about 13 m of depth above the present lake bottom. The method presented in this paper generates very detailed palaeogeographical maps that are particularly useful for reconstructing lake changes in semiarid environments as a function of climate change.  相似文献   

12.
内蒙古呼伦贝尔草原湖泊变化研究   总被引:1,自引:0,他引:1  
内蒙古呼伦贝尔地区湖泊数量多,面积大,占内蒙古湖泊总面积的58%.近年来该地区湖泊趋于萎缩,但是已有研究主要关注大型湖泊,缺乏对该地区湖泊整体,尤其是小型湖泊(<1 km2)的研究.通过利用Landsat系列(TM、ETM+、OLI)卫星数据,参照该地区湖泊图集、湖泊名录以及Google Earth高清影像,分析了19...  相似文献   

13.
近35 a来新疆干旱区湖泊变化及原因分析   总被引:3,自引:1,他引:2  
朱刚  高会军  曾光 《干旱区地理》2015,38(1):103-110
应用“3S”技术,以流域为单元,对新疆干旱区1975-2010年近35 a来湖泊的变化进行了研究。研究结果表明:湖泊总体呈数量多、规模小的特点,以天然湖泊为主,湖泊分布面积最大的流域为准噶尔内流区、分布数量最多的流域为塔里木内流区;35 a来湖泊的变化呈1975-2000年数量与面积增大、2000-2010年数量与面积减少的特征;天然湖泊与人工湖泊变化差异显著,天然湖泊数量与面积均呈先增加后减少的变化特征,而人工湖泊数量及面积均呈持续增加的变化特征;1975-2000年各流域湖泊面积均增大,2000-2010年除伊犁河内流区外,各流域湖泊面积均大幅度减小;影响新疆干旱区湖泊变化的主要气候因素是降水与气温,人类活动是流域间湖泊变化幅度与变化趋势差异的主要影响因素,也是影响天然湖泊与人工湖泊变化趋势差异的主要原因。  相似文献   

14.
博斯腾湖的水环境保护与可持续利用对策   总被引:14,自引:1,他引:13  
本文通过实地调查和对1999~2001年的监测资料的分析,从水环境污染物特性、水环境质量变化、排污源分布及排污量计算等方面探讨了博斯腾湖水环境问题及其成因。提出建立博斯腾湖保护区,加大管理检查和执法力度,加强对农田排污水的控制,强化重点排污口和重点城镇生活污水的排污管理,并通过湖滨湿地生态恢复工程、增源节水工程、加速湖水循环工程等措施,保护和改善博斯腾湖水环境  相似文献   

15.
肖飞  杜耘  凌峰  吴胜军  严翼 《湿地科学》2012,10(1):8-14
分析了20世纪20年代以来长江中游四湖流域湖泊阶段性变化特征,并结合湖区土壤空间分布数据,重点探讨现代土壤空间格局与湖泊的阶段性变化是否存在关联。研究结果表明,从20世纪20年代至今,江汉平原四湖流域湖泊经历了由扩大到缩小至稳定的阶段性变化过程;通过湖泊变迁序列与湖区土壤格局的综合分析,发现四湖流域湖泊变化范围内的土壤空间分异与20世纪20年代以来湖泊变化历程具有密切关系。20世纪20年代以来,四湖流域湖泊变化范围集中分布了全流域67%以上的潜育型水稻土和沼泽型水稻土;在四湖流域自20世纪40年代起的湖泊萎缩阶段,湖泊变化时间距今愈近,相应湖泊变化范围中沼泽型水稻土和潜育型水稻土面积比例愈大,淹育型水稻土和潴育型水稻土面积比例则愈小。在湖泊变化不同时间组合所对应的空间范围中,各类型水稻土所占面积比例随时间变化而表现的规律性,在一定程度表现出人为耕作及土壤性质改良对土壤性质转变的影响作用;而根据沼泽型水稻土转变速率的空间差异性,可推测湖区脱沼泽过程与地形地貌分异相关。  相似文献   

16.
青藏高原的隆升过程是一个长期的大地构造运动演化过程,是多个陆块从冈瓦纳裂解向北漂移在不同时间与欧亚碰撞的结果,羌塘盆地是我国重要的中生代成盐盆地,具有良好的成盐成钾条件,通过前期研究中依据室内海水蒸发实验模拟结果提出的多级盆地海水迁移变质成盐成钾模式,对羌塘地区开展找钾工作具有重要的指导意义。同时摸清盐湖资源中钾、锂、镁、硼关键元素的成矿、迁移和富集规律,对后端盐湖资源的科学保护与合理开发具有重要意义。并且尝试阐明水-岩-盐系统的资源关联性和资源元素迁移的“源-汇”地球化学过程。在盐湖的探索和开放同时做好重点盐湖开发地区的生态环境影响评价是构筑青藏高原生态安全屏障的重要组成内容和刚性需求,为生态环境保护前提下的盐湖资源开发提供了重要科学依据。通过该盐湖科学数据库功能的深度开发,构建科学数据共享平台。对青藏高原盐湖科学数据进行有效的梳理和科学管理。青藏高原是我国重要的生态屏障,也是重要的盐湖分布区。本次盐湖专题科考聚焦青藏高原盐湖,经过近三年的科考工作,获得了大量一手科考数据,将继续推动二次科考成果转化,探索盐湖的绿色高质量发展途径,为建设世界级盐湖产业基地助力。  相似文献   

17.
As one of the areas with numerous lakes on the Tibetan Plateau, the Hoh Xil region plays an extremely important role in the fragile plateau eco-environment. Based on topographic maps in the 1970s and Landsat TM/ETM+ remote sensing images in the 1990s and the period from 2000 to 2011, the data of 83 lakes with an area above 10 km2 each were obtained by digitization method and artificial visual interpretation technology, and the causes for lake variations were also analyzed. Some conclusions can be drawn as follows. (1) From the 1970s to 2011, the lakes in the Hoh Xil region firstly shrank and then expanded. In particular, the area of lakes generally decreased during the 1970s–1990s. Then the lakes expanded from the 1990s to 2000 and the area was slightly higher than that in the 1970s. The area of lakes dramatically increased after 2000. (2) From 2000 to 2011, the lakes with different area ranks in the Hoh Xil region showed an overall expansion trend. Meanwhile, some regional differences were also discovered. Most of the lakes expanded and were widely distributed in the northern, central and western parts of the region. Some lakes were merged together or overflowed due to their rapid expansion. A small number of lakes with the trend of area decrease or strong fluctuation were scattered in the central and southern parts of the study area. And their variations were related to their own supply conditions or hydraulic connection with the downstream lakes or rivers. (3) The increase in precipitation was the dominant factor resulting in the expansion of lakes in the Hoh Xil region. The secondary factor was the increase in meltwater from glaciers and frozen soil due to climate warming.  相似文献   

18.
Inland lakes and alpine glaciers are important water resources on the Tibetan Plateau. Understanding their variation is crucial for accurate evaluation and prediction of changes in water supply and for retrieval and analysis of climatic information. Data from previous research on 35 alpine lakes on the Tibetan Plateau were used to investigate changes in lake water level and area. In terms of temporal changes, the area of the 35 alpine lakes could be divided into five groups: rising, falling-rising, rising-falling, fluctuating, and falling. In terms of spatial changes, the area of alpine lakes in the Himalayan Mountains, the Karakoram Mountains, and the Qaidam Basin tended to decrease; the area of lakes in the Naqu region and the Kunlun Mountains increased; and the area of lakes in the Hoh Xil region and Qilian Mountains fluctuated. Changes in lake water level and area were correlated with regional changes in climate. Reasons for changes in these lakes on the Tibetan Plateau were analyzed, including precipitation and evaporation from meteorological data, glacier meltwater from the Chinese glacier inventories. Several key problems, e.g. challenges of monitoring water balance, limitations to glacial area detection, uncertainties in detecting lake water-level variations and variable region boundaries of lake change types on the Tibetan Plateau were discussed. This research has most indicative significance to regional climate change.  相似文献   

19.
冰湖的界定与分类体系——面向冰湖编目和冰湖灾害研究   总被引:4,自引:0,他引:4  
姚晓军  刘时银  韩磊  孙美平 《地理学报》2017,72(7):1173-1183
冰川湖泊(简称冰湖)不仅是高山区重要的水资源,而且是许多冰川灾害的孕育者和发源地,在冰冻圈科学、气候变化和山地灾害研究中具有重要地位。本文系统讨论了现有冰湖定义及存在的问题,从冰湖编目和冰湖灾害研究视角提出冰湖的定义,指出现有冰湖研究主要是基于“以现代冰川融水为主要补给源或在冰碛垄洼地内积水形成的天然水体”这一冰湖定义的。同时,从冰湖形成机理、地貌形态和空间分布位置将冰湖划分为冰川侵蚀湖(冰斗湖、冰川槽谷湖和其他冰川侵蚀湖)、冰碛阻塞湖(终碛阻塞湖、侧碛阻塞湖、冰碛垄热融湖)、冰川阻塞湖(冰川前进阻塞湖和其他冰川阻塞湖)、冰面湖、冰下(内)湖和其他冰川湖6大类及8个亚类,并给出各冰湖类型相应的遥感判识指标和定量指标,以期建立具有普适性和可操作性的冰湖分类体系。  相似文献   

20.
Inland lakes and alpine glaciers are important water resources on the Tibetan Plateau. Understanding their variation is crucial for accurate evaluation and prediction of changes in water supply and for retrieval and analysis of climatic information. Data from previous research on 35 alpine lakes on the Tibetan Plateau were used to investigate changes in lake water level and area. In terms of temporal changes, the area of the 35 alpine lakes could be divided into five groups: rising, falling-rising, rising-falling, fluctuating, and falling. In terms of spatial changes, the area of alpine lakes in the Himalayan Mountains, the Karakoram Mountains, and the Qaidam Basin tended to decrease; the area of lakes in the Naqu region and the Kunlun Mountains increased; and the area of lakes in the Hoh Xil region and Qilian Mountains fluctuated. Changes in lake water level and area were correlated with regional changes in climate. Reasons for changes in these lakes on the Tibetan Plateau were analyzed, including precipitation and evaporation from meteorological data, glacier meltwater from the Chinese glacier inventories. Several key problems, e.g. challenges of monitoring water balance, limitations to glacial area detection, uncertainties in detecting lake water-level variations and variable region boundaries of lake change types on the Tibetan Plateau were discussed. This research has most indicative significance to regional climate change.  相似文献   

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