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青藏高原现代湖泊变化与考察初步报告 总被引：18，自引：5，他引：13
青藏高原广布的湖泊敏感地记录着气候与环境变化过程的信息．因它在地球中、低纬度地区最少受人类活动干扰,环境的演化变迁忠实地反映了纯自然过程,因此继南、北极之后,青藏高原正在成为研究全球变化的新的热点地区．青藏高原上的湖泊绝大部分为封闭湖盆,湖泊水位的变化直接记录着流域内的水量平衡变化过程．可敏感反映气候的变化．湖泊水化学性质记录了湖泊自身的演化历史,湖泊沉积物则包含着丰富的湖泊物理、化学、生物的沉积过程信息,这些过程与气候、环境演变又有着密切的关系．为了探讨湖泊沉积物和湖泊水体中的物理、化学、生物… 相似文献
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近40年青藏高原湖泊面积变化遥感分析 总被引：13，自引：7，他引：6
以MSS、TM和ETM遥感影像作为主要信息源,综合利用RS、GIS技术,提取青藏高原1970s、1990s、2000s及2010s 4个时段的湖泊面积信息,分别从区域位置、面积规模、海拔高度3方面分析其近40年来的变化趋势及变化特征,同时结合1972-2011年间青藏高原气候变化情况,初步探讨了影响青藏高原湖泊面积变化的主要原因.研究结果表明:(1)青藏高原面积大于10 km2的湖泊有417个,这些湖泊大多是面积为10~100 km2的小型湖泊,空间上集中分布在高原西部地区,海拔上集中在4500~5000 m范围内;(2)近40年青藏高原湖泊面积的变化趋势及差异性特征在整体上表现为湖泊呈加速扩张的趋势,其中2000s-2010s时段是湖泊扩张最显著的时期;在区域位置上,北部地区的湖泊变化最为剧烈;在面积规模上,小型湖泊扩张最为显著;在海拔高度上,低海拔地区湖泊扩张剧烈;(3)近40年青藏高原气候暖湿化程度明显,气候变化对湖泊面积变化影响显著;在气象要素中,降水量的变化是青藏高原湖泊面积变化的主要驱动因子. 相似文献
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西藏著名圣湖之一的当惹雍错,是藏北高原腹地内陆封闭大湖,对湖泊面积变化的长时间序列研究较少,本文通过高分辨率陆地资源卫星Landsat TM/ETM+数据源,利用遥感和地理信息系统软件,通过人工目视解译方法对1977-2014年当惹雍错湖泊面积变化进行系统分析,并结合流域临近气象站资料,流域冰川等辅助数据对其湖泊面积变化原因进行综合分析.结果表明,1977-2014年当惹雍错湖泊平均面积为835.75 km~2,1977-2014年湖泊面积总体呈上升趋势,1970s湖泊平均面积为829.15 km~2,1980s和1990s湖泊平均面积分别为827.50和826.42 km~2,2000年之后湖泊面积明显增加,2000s湖泊平均面积与1970s相比,增幅为8.04 km~2.当惹雍错湖泊空间变化特点是,位于最大河流入口处达尔果藏布的湖泊东南部扩大明显,湖泊西南部小湖1于2014年9月开始明显扩大并与当惹雍错有相连趋势;流域冰川融水是当惹雍错主要补给源,近40 a当惹雍错湖泊面积变化是在气温升高的背景下,冰川、降水量和蒸发量三者共同变化作用的结果. 相似文献
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2002年腾格里沙漠湖泊季节变化研究 总被引：2，自引：1，他引：1
以2002年的6期ETM+遥感影像作为数据源,采用面向对象的解译方法,自动提取腾格里沙漠一年内6个时期的湖泊信息,对湖泊季节变化情况进行统计,并与巴丹吉林沙漠的湖泊季节变化进行对比分析.结果表明,腾格里沙漠湖泊的季节变化显著,湖泊总数量及总面积在夏季(6月)达最大值,在冬季(12、2月)最小;两大沙漠湖泊季节变化情况不尽相同,可能与两大沙漠湖泊水的补给方式存在差异有关,腾格里沙漠湖泊水量变化更多地受近源地下水的影响,而巴丹吉林沙漠湖泊水量变化则主要受远源地下水影响. 相似文献
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近45a内蒙古浑善达克沙地湖泊群的变化 总被引：1，自引：1，他引：0
浑善达克沙地处于季风边缘区,其气候特性和人类活动决定了该地区生态系统的脆弱和环境变化的敏感性.目前,该区湖泊生态环境问题十分严重,对研究区的水资源、草原景观以及当地居民生产生活造成了严重影响.选取1969年1∶50000地形图所指示的面积≥0.01 km~2的175个湖泊为研究对象,结合1973-2013年的17期Landsat MSS/TM/ETM/OLI卫星遥感影像数据,对1969-2013年间的湖泊群变化进行了系统的研究和初步探讨.结果表明:1969年湖泊群总面积为502.04 km~2,而2013年其面积为303.42 km~2,总体呈萎缩趋势.其中面积萎缩和干涸的湖泊分别为88和85个,而面积扩张的湖泊仅有2个(人工筑坝所致).近45 a间,1970s-1980s湖泊面积波动性减少,而在1990s初期则出现持续上升状态.在1995-2011年湖泊面积总体下降,到2013年则出现微弱的扩张现象.从湖泊变化空间分布格局来看,萎缩和干涸的湖泊集中在该沙地腹地. 相似文献
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全球变化下青藏高原湖泊在地表水循环中的作用 总被引：2，自引：2，他引：0
青藏高原是地球上最重要的高海拔地区之一,对全球变化具有敏感响应.青藏高原作为"亚洲水塔",其地表水资源及其变化对高原本身及周边地区的经济社会发展具有重要的影响.然而,在气候变暖的情况下,构成高原地表水资源的各个组分,如冰川、湖泊、河流、降水等水体的相变及其转化却鲜为人知.湖泊是青藏高原地表水体相变和水循环的关键环节.湖泊面积、水位和水量对西风和印度季风的降水变化非常敏感,但湖泊面积和水量变化在不同区域和时段的响应也不尽相同.湖泊水温对气候变暖具有明显响应,湖泊水温和水下温跃层深度的变化能够对水—气的热量交换具有明显影响,从而影响了区域蒸发和降水等水循环过程.由于湖泊水量增加,高原中部色林错地区湖泊盐度自1970s以来普遍下降.根据60多个湖泊实地监测建立的遥感反演模型研究发现,2000—2019年湖泊透明度普遍升高.对不同补给类型的大湖水量平衡监测发现,影响湖泊变化的气象和水文要素具有较大差异.在目前的暖湿气候条件下,青藏高原的湖泊将会持续扩张.为了深入认识湖泊变化在青藏高原区域水循环和气候变化中的作用,需要全面了解湖泊水量赋存及连续的时间序列变化,需要深入了解湖泊理化参数变化及对湖泊大气之间热量交换的影响,需要更多来自大湖流域的综合连续观测数据. 相似文献
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近30年三江源地区湖泊变化图谱与面积变化 总被引：7，自引：2，他引：5
以近30年的40景Landsat MSS/TM/ETM+、CBERS CCD遥感影像为数据源,采用植被指数法结合人工目视解译,分为四个时期对三江源地区湖泊进行了遥感水体检测.选取面积在15km2以上、总面积占研究区湖泊总面积的90%左右的24个湖泊作为典型湖泊,建立该地区湖泊的变化图谱,并引入湖泊萎缩强度指数对湖泊的面积变化及空间分布特征进行分析.结果表明,以第三时期(1999-2002年)为界,这24个湖泊总体上经历了先萎缩后扩张的过程,且萎缩的程度大于扩张的程度,近30年来湖泊总面积缩小了65.76km2.本文研究结论可为三江源地区对气候变化响应研究提供参考,并对区域水资源合理利用提供科学依据. 相似文献
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青藏高原湖泊古今变化的遥感分析——以达则错为例 总被引：9，自引：4，他引：5
青藏高原湖泊受人类活动干扰较少,主要受气候变化导致的冰川融化和蒸发的影响,是气候变化直观敏感的反映区。因此,研究青藏高原湖泊变化对区域以至全球气候、环境变化的研究具有深远意义。本文在遥感影像的基础上发展了综合指数计算与空间分异的现存湖迭代提取方法,对影像数据上的湖泊进行动态监测;并结合DEM数据发展了半自动化的古岸线提取方法,进而分析古湖泊的变化,二者相结合直观全面地反映出了青藏高原湖泊的古今变化情况。并以达则错湖为例进行提取,分析了其近25年以来以及大湖期以来的缩减情况 相似文献
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Heterogeneous change patterns of water level for inland lakes in High Mountain Asia derived from multi‐mission satellite altimetry 
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下载免费PDF全文 High‐altitude inland lakes in High Mountain Asia (HMA) are key indicators to climate change and variability as a result of mostly closed watersheds and minimal disturbance by human activities. However, examination of the spatial and temporal pattern of lake changes, especially for water‐level variations, is usually limited by poor accessibility of most lakes. Recently, satellite altimeters have demonstrated their potential to monitor water level changes of terrestrial water bodies including lakes and rivers. By combining multiple satellite altimetry data provided by the Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS) and Geoscience Laser Altimeter System (GLAS) instrument on the NASA Ice, Cloud and land Elevation satellite (ICESat), this study examined water level changes of typical lakes in HMA at a longer timescale (in the 1990s and 2000s) compared with earlier studies on Tibetan lakes. Cross‐evaluation of the radar altimetry data from LEGOS and laser altimetry data from ICESat/GLAS shows that they were in good agreement in depicting inter‐annual, seasonal and abrupt changes of lake level. The long‐term altimetry measurements reveal that water‐level changes of the 18 lakes showed remarkable spatial and temporal patterns that were characterized by different trends, onsets of rapid rises and magnitudes of inter‐annual variations for different lakes. During the study period, lakes in the central and northern HMA (15 lakes) showed a general growth tendency, while lakes in South Tibet (three lakes) showed significant shrinking tendency. Lakes in Central Tibet experienced rapid and stable water‐level rises around mid‐1990s followed by slowing growth rates after 2006. In contrast, the water‐level rises of lakes in the northern and north‐eastern Tibetan Plateau were characterized by abrupt increases in specific years rather than gradual growth. Meteorological data based on station observations indicate that the annual changes of water level showed strongly correlated with precipitation and evaporation but may not evidently related to the glacier melting induced by global warming. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Lide Tian Zhongfang Liu Tongliang Gong Changliang Yin Wusheng Yu Tandong Yao 《水文研究》2008,22(17):3386-3392
The use of stable isotopes is a practical tool in the study of the lake water budget. This is an one way to study the hydrological cycle in the large numbers of inland lakes on the Tibetan Plateau, in which the isotope record of the sediment is believed to reflect the climatic and environmental changes. The monitoring of stable isotopes of the precipitation, river and lake waters during 2004 in the inland Yamdruk‐tso basin, southern Tibetan Plateau, reveals the lake water δ18O is over 10‰ higher than the local precipitation. This high difference indicates strong isotope enrichment due to lake water evaporation. The simulation results based on the isotope technique show that the present lake water δ18O level corresponds to an average relative humidity of around 54–58% during evaporation, which is very close to the instrumental observation. The simulation results also show that the inland lakes on the Tibetan Plateau have a strong adjustability to the isotope shift of input water δ18O. On average, the isotope component in the inland lake water is to a large extent controlled by the local relative humidity, and can also be impacted by a shift of the local precipitation isotope component. This is probably responsible for the large consistence in the isotope component in the extensive inland lakes on the Tibetan Plateau. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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在全球气候变暖和极端气候事件增加的背景下,流域水文循环过程受到的影响越来越强烈,导致湖泊水位变化表现出复杂的时空特征。而泛北极地区是地球上湖泊数量与面积分布最为集中的区域之一,该地区湖泊对气候变化响应非常敏感。因此,了解这些湖泊近期水文变化特征十分必要。本研究共搜集了36个泛北极大型湖泊(>500 km2)基于遥感或站点观测的近20年水位数据,分析其时空变化特征。本文使用线性回归模型来估算湖泊水位的变化趋势,进而利用皮尔逊相关分析了其主要水文影响变量和大气环流机制,并运用Mann-Kendall突变检验法探讨了水位突变的原因。结果表明,泛北极湖泊的水位整体上呈现不同程度上升(平均速率为0.013 m/a),有23个(64%)湖泊的水位呈上升趋势;研究湖泊中有10个通过90%统计显著性检验。其中,水位上升速率最大的湖泊是位于哈萨克斯坦的腾吉兹湖,上升速率为0.078 m/a。泛北极湖泊水位的波动主要与径流有关,有19个(53%)湖泊的水位波动与径流的增加更为相关;相比而言,位于亚洲的极地湖泊水位的上升与流域蒸发的降低显著相关,尤其是库苏古尔湖。从区域大气环流影响来看,泛北极湖泊水位变化主要与厄尔尼诺-南方涛动有关,其次是北极涛动和北大西洋涛动。本研究有助于加深对泛北极湖泊近20年水位变化规律及气候影响特征的科学理解。 相似文献
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Sensitivity of physical lake processes to climate change within a large Precambrian Shield catchment 下载免费PDF全文
下载免费PDF全文 Potential future changes in lake physical processes (e.g. stratification and freezing) can be assessed through exploring their sensitivity to climate change, and assessing the current vulnerability of different lake types to plausible changes in meteorological drivers. This study quantifies the impacts of climate change and sensitivity of lake physical processes within a large (5100 km2) Precambrian Shield catchment in south‐central Ontario. Historic regional relationships are established between climate drivers, lake morphology, and lake physical changes through generalized linear modelling (GLM), and are used to quantify likely changes in timing of ice phenology and lake stratification across 72 lakes under a range of future climate models and scenarios. In response to projections of increased temperature (ensemble mean of +3.3 °C), both earlier ice‐off and onset of summer stratification were projected, with later ice‐on and fall turnover compared to the baseline. Process sensitivity to climate change varied by lake type; shallower lakes with a smaller volume (less than 15 m deep and less than 0.05 km3) were more sensitive to processes associated with lake heating (stratification onset and ice‐off), and deeper lakes with a larger surface area (greater than 30 m deep and greater than 1000 ha) were more sensitive to processes associated with lake cooling (fall turnover and ice‐on). These results indicate that whereas small lakes are vulnerable to climate warming because of changes that occur in spring and summer, larger lakes are particularly sensitive during the fall. The findings suggest that lake morphology and associated sensitivity should be considered in the development of sustainable lake management strategies. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Differences and cause analysis of changes in lakes of different supply types in the north‐western Tibetan Plateau 下载免费PDF全文
下载免费PDF全文 Most lakes of the Tibetan Plateau were experiencing quick expansion in recent decades; a detailed study on the changes in lakes of different supply types will help to understand the cause of the changes by analysing area change of 34 lakes and water level change of eight lakes in the north‐western Tibetan Plateau. All lakes are classified into three types: non‐glacier‐fed lakes, upstream lakes and glacier‐fed lakes. The glacier‐fed lakes are separated into glacier‐fed_P1 (quick expansion region) and glacier‐fed_P2 (slow expansion region). Combining the changes in precipitation, temperature and evaporation, less precipitation may be the main reason for lake shrinkage from 1976 to 1996 and quickly increasing precipitation led to the lakes' expansion from 1996 to 2000. However, after 2000, upstream lakes remained in a stable state with slight variation, non‐glacier‐fed lakes and glacier‐fed_P2 lakes exhibited a slightly increasing rate with high precipitation and high evaporation, and glacier‐fed_P1 lakes still expanded quickly. On the basis of the assumption of same precipitation and evaporation, glacial meltwater may make an important contribution (>52%) to the increase in water storage of Bangdag Co and Meima Co. The results suggest that glacial meltwater augments the increased rate of glacier‐fed_P2 lakes and plays a much more important role in the expansion of glacier‐fed_P1 lakes compared to other lakes. 相似文献
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长江中下游典型湖泊营养盐历史变化模拟 总被引：2，自引：1，他引：1
湖泊营养盐变化在自然条件下受到气候水文因素控制,同时受到湖泊生态系统生物群落作用和反馈.作为动力机制探讨,本文试图基于水文和生态动力学方法,分别构建气候-流域水文作用于湖泊营养盐的外源模式和湖泊生物群落作用于湖泊营养盐的內源模式.针对长江中下游典型湖泊,经过控制实验和率定,发现营养盐模拟与观测数据在时间序列上达到90%百分位的正相关,因此用来模拟1640 1840 A.D.期间的营养盐演变历史.研究表明:(1)模拟的湖泊营养盐变化与沉积钻孔揭示的历史营养盐变化基本一致,沉积记录与模式模拟的7个湖泊的营养盐变化均显著相关;(2)气候因素是湖泊营养盐历史演变的主控因子,来自于湖泊生物群落的反馈作用贡献约占40%;(3)在温度和降水因子的驱动下,湖泊营养盐历史变化主要受降水控制,在极端干旱时期,60%的营养盐变化同步响应于降水变化.同时,面积在400 km2以下的湖泊营养盐对气候变化的响应比2000 km2以上的大湖更为敏感.研究结果对长江中下游湖泊营养状态的长期变化机理认识和趋势控制提供科学依据. 相似文献