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1.
A study is made of the northern spurs of the Tsagan-Daban Range in the Transbaikalia which are represented by Central-Asian and North-Asian taiga geosystems. The investigations of landscape structure were made in two key areas characterized by an alternation of mountain ranges and intermontane depressions (creek valleys).  相似文献   

2.
Results from investigating the geosystems of Cisbaikalia in its western and eastern parts (Primorskii Range and Barguzin Range, respectively) are presented. For studying three macroslopes of these mountain ranges (having an easterly aspect for the Primorskii Range and a westerly and south-easterly aspect for the Barguzin Range), the regional background and the main factors of the landscape differentiation of the study areas were analyzed. Structural features of topological geosystems are revealed, and large-scale maps of key areas are compiled (at a scale of 1:50 000). Maps of the landscape-typological structure were created on the basis of the structural-dynamic and facies analysis of landscapes. It is established that the main factors influencing the landscape diversity are the aspect and steepness of the slopes, the composition and structure of rocks, the absolute height, the amount of atmospheric precipitation, and anthropogenic impacts. It is determined that the influence of the lithomorphic factor is widespread throughout the study areas, the hydromorphic factor is also important, the cryomorphic factor occurs additionally in the goletz zone, and the xeromorphic factor is only observed on the Baikal Range and on the coastal plain in some areas of Priolkhonie. The dynamic aspect of the landscape structure and the relationships between geosystems are displayed in map legends.  相似文献   

3.
Using the glaciers of the Munku-Sardyk massif as an example, we examine the patterns of changes of glaciological landscapes as revealed through instrumental observations. We present the quantitative parameters of the dynamics of nival-glacial geosystems obtained by using state-of-the-art remote sensing and GIS analysis facilities. Interesting new features reflecting the state of geosystems are described, and particularizing geoinformation calculations and a mapping are performed for a subsequent monitoring of their state.  相似文献   

4.
Separate mountain massifs, separated by a considerable distance from one another, exhibit in their evolutionary development some similar traits. On the other hand, mountain geosystems occurring in them show differences associated with the location of the mountains, their morphological structure and climatic conditions. Global warming has been producing changes in the dynamics of mountain geosystems over the last three decades. However, the response of nival-glacial intracontinental geosystems is different from that in near-oceanic regions.  相似文献   

5.
The precise glacier boundary is a fundamental requirement for glacier inventory,the assessment of climate change and water management in remote mountain areas.However,some glaciers in mountain areas are covered by debris.The high spatial resolution images bring opportunities in mapping debris-covered glaciers.To discuss the capability of Chinese GaoFen-1 satellite lacking the short wave infrared band and thermal infrared band in mapping glaciers,this study distinguished supraglacial terrain from surrounding debris by combining GaoFen-1(GF-1)wide-field-view(WFV)images,the ratio of the thermal infrared imagery and morphometric parameters(DEM and slope)with 30 m resolution.The overall accuracy of 90.94%indicated that this method was effective for mapping supraglacial terrain in mountain areas.Comparing this result with the combination of GF-1 WFV and low-resolution morphometric parameters shows that a high-quality DEM and the thermal infrared band enhanced the accuracy of glacier mapping especially debris-covered ice in steep terrain.The user's and producer's accuracies of glacier area were also improved from 89.67%and 85.95%to 92.83%and 90.34%,respectively.GF data is recommended for mapping heavily debris-covered glaciers and will be combined with SAR data for future studies.  相似文献   

6.
Presented are the technique and results of studying the landscape structure of the north-west of Western Siberia on the basis of the Hansen mosaic dataset consisting of elements covering the entire territory of the Earth. To study this area used a synthesis of classical methods of thematic system mapping as described in the doctrine of geosystems of V. B. Sochava, and automated interpretation of remote sensing data and mapping using GIS technologies. The method of geoinformational mapping of the landscape structure with the use of MultiSpec and Quantum GIS software programs for the purpose of drawing up real-time raster landscape maps is shown. In drawing up the map and the legend, the principle of geomic system-hierarchical representation of the territory as a complex multi-level “bottom-up” structure from topological-level geosystems (groups and classes of landscape facies) to regional-level geosystems (geoms, groups and classes of geoms) was used. Compilation of operational raster landscape maps of the north-west of Western Siberia involved multilevel automated interpretation of the Hansen mosaic dataset and mapping of areas (clusters) on images with different brightness characteristics, with the landscape structure of key areas and stationary physical and geographical profiles. A characteristic of this approach also implies using a dynamic classification of geosystems based on the study of their variable states. Such an approach permits a monitoring of changes in landscape structure and its areas and the intensity of anthropogenic impacts on forest and marsh landscapes, and determination of permissible pressure on geosystems in areas with high technogenic pressure of the oil and gas complex represented by the north-west of Siberia. An automated processing of data based on a supervised classification of territorial objects allows for the elimination of inaccuracies arising in visual image interpretation. Raster landscape maps can be used both for a further generation of vector maps and as a real-time information base for purposes of environmental management and protection.  相似文献   

7.
An analysis is made of the glaciation status of the mountains in the south of East Siberia to reveal a number of characteristics of changes in glacier systems. It is determined that the mountain systems are all experiencing a deglaciation caused by global climatic changes, while the rates of degradation have increased considerably since the late 1980s. It is established that over the last several decades the rate of thawing of glaciers has decelerated according to data for the key sites in the Kodar, Baikal’skii, Barguzin. Munku-Sardyk and Eastern-Sayan mountain ranges, which is associated with a decrease in mean annual air temperatures in 2009, 2010, 2012 and 2013 after the maximum values in 1990, 1994, 1995, 1997, 2002 and 2007. The changes recorded in the amount of solid atmospheric precipitation do not produce any definite trends in all of the mountain systems analyzed. It is determined that, given a relatively small snow accumulation, the glaciers are fed by snow avalanches and persist due to accumulation of large reserves of cold throughout long and cold winters which impede an intense ablation and promote the sustenance of glaciation. It is pointed out that the thawing of glaciers (especially cirque glaciers) involves a decrease in their thickness, whereas their area changes little.  相似文献   

8.
This investigation is concerned with the problem of recognition of glacial landforms in arid mountainous areas of Asia using satellite imagery. We examine the territory of the Mongun-Taiga mountain range located at the interface of the Russian Altai, Sayan and Mongolian Altai mountains which has been studied for many years by geographers of St. Petersburg State University. The mountain range is home to modern glaciers totaling about 20 km in area, and its climate aridity is favorable for the preservation of a large body of evidence of ancient glaciation. The theoretical basis for this effort was provided by the idea of GC, i. e. natural complexes, the morphology and structure of which is formed by modern and ancient glaciations. Using the morphological differences we identified three groups of glaciogenic complexes and assigned their formation time to MIS 4, MIS 2, and to the Late Holocene. Results from comparing data of glacio-geomorphological and paleogeographical studies on the territory of the Mongun-Taiga mountain range with corresponding satellite images were used to develop interpretation standards for different groups of GC, forming the basis for compiling the map of GC of the second and third order for the entire mountain range. Cartometric measurements were used in obtaining the main characteristics of the glaciers of the Mogun-Taiga for ten different time spans. It is found that during the MIS 4 maximum the glaciers advanced to the piedmonts, and their area exceeded the present-day area by more than a factor of 25, with the firn line depression of about 800 m. The largest areas were occupied by glaciers of southward aspects, which is accounted for by a predominance of north-westward moisture-bearing glacial streams at that time. The aspect asymmetry of glaciation persisted during the MIS 2 maximum but it had a valley character. It is established that in the Little Ice Age the area of the glaciers exceeded the present-day area by a factor of 2.4, with the firn line depression of 20 m.  相似文献   

9.
Mountain glaciers have an obvious location advantage and tourist market condition over polar and high latitude glaciers. Due to the enormous economic benefit and heritage value, some mountain glaciers will always receive higher attention from commercial media, government departments and mountain tourists in China and abroad. At present, more than 100 glaciers have been developed successfully as famous tourist destinations all over the world. However, global climate change seriously affects mountain glaciers and its surrounding environment. According to the current accelerated retreat trend, natural and cultural landscapes of some glaciers will be weakened, even disappear in the future. Climate change will also inevitably affect mountain ecosystems, and tourism routes under ice and glacier experience activities in these ecosystems. Simultaneously, the disappearance of mountain glaciers will also lead to a clear reduction of tourism and local economic benefits. Based on these reasons, this paper took Mt. Yulong Snow scenic area as an example and analyzed the retreat trend of a typical glacier. We then put forward some scientific and rational response mechanisms and adaptation models based on climate change in order to help future sustainable development of mountain glacier tourism.  相似文献   

10.
青藏高原可可西里地区现代冰川发育特征   总被引:5,自引:1,他引:5  
李世杰 《地理科学》1996,16(1):10-17
经野外考察和室内分析计算,青藏可可西里地区发育现代冰川437条,覆盖面积达1552.39km^2,冰储量为162.8349km^3,成为本区众多河湖泊水体的重要补给源泉。  相似文献   

11.
天山冰川与湖泊变化所示的气候趋势   总被引:2,自引:1,他引:2  
天山山系深居亚洲大陆腹地,受中亚自然地理环境的制约,在变性西风气流的影响下,70年代至今山地冰物质平衡负值,伴随着气温的变化而增大。湖泊则是随着山区降水量的增加,其面积渐增。气温与降水的相互作用,使得整修天山山系的水资源总量趋于正常略偏多。预期这种气候趋势将会延续到下世纪初期。  相似文献   

12.
近30年来天山托木尔峰东侧分水岭处冰川变化   总被引:7,自引:4,他引:3  
利用1978年出版的航测地形图与1976年MSS影像(地形图于20世纪70年代初期测绘)、1990年landsatTM影像、2002年CBERS影像对西天山托木尔峰以东分水岭处的5条冰川近30年来的动态变化进行了研究。研究结果表明,这5条冰川在1970年代初-2002年近30年来整体上处于退缩状态,这与该地区20世纪80、90年代气温升高导致冰雪消融加速而冬季降水量基本稳定即补给来源基本不变的趋势是相符合的。这也表明,在气候变暖的趋势下,该地区冰川的补给-消融动态平衡关系被打破,冰川总体上处于退缩状态。  相似文献   

13.
One of the most glacierized areas in the European Alps, the Mont Blanc massif, illustrates how fast changes affect the cryosphere and the related morphodynamics in high mountain environments, especially since the termination of the Little Ice Age. Contrasts between the north‐west side, gentle and heavily glaciated, and the south‐east side, steep and rocky, and between local faces with varying slope angle and aspect highlight the suitability of the study site for scientific investigations. Glacier shrinkage is pronounced at low elevation but weaker than in other Alpine massifs, and supraglacial debris covers have developed over most of the glaciers, often starting in the nineteenth century. Lowering of glacier surface also affects areas of the accumulation zone. While modern glaciology has been carried out in the massif for several decades, study of the permafrost has been under development for only a few years, especially in the rock walls. Many hazards are related to glacier dynamics. Outburst flood from englacial pockets, ice avalanche from warm‐based and cold‐based glaciers, and rock slope failure due to debuttressing are generally increasing with the current decrease or even the vanishing of glaciers. Permafrost degradation is likely involved in rockfall and rock avalanche, contributing to the chains of processes resulting from the high relief of the massif. The resulting hazards could increasingly endanger population and activities of the valleys surrounding the Mont Blanc massif.  相似文献   

14.
On the basis of space-acquired images from the Landsat 7,7 satellites (1992, 2002) and the topographic map at a scale of 1:200 000 (1969), we investigated the patterns of spatio-temporal changes of glaciation of the plexus of the Turgan-Kharkhira mountains (Western Mongolia). The study ascertained the dynamics of the areas and volumes of the glaciers for 33 years as well as the changes in glacier runoff for five mountain river basins.  相似文献   

15.
Glaciers are the most important fresh-water resources in arid and semi-arid regions of western China. According to the Second Chinese Glacier Inventory (SCGI), primarily compiled from Landsat TM/ETM+ images, the Qilian Mountains had 2684 glaciers covering an area of 1597.81±70.30 km2 and an ice volume of ~84.48 km3 from 2005 to 2010. While most glaciers are small (85.66% are <1.0 km2), some larger ones (12.74% in the range 1.0–5.0 km2) cover 42.44% of the total glacier area. The Laohugou Glacier No.12 (20.42 km2) located on the north slope of the Daxue Range is the only glacier >20 km2 in the Qilian Mountains. Median glacier elevation was 4972.7 m and gradually increased from east to west. Glaciers in the Qilian Mountains are distributed in Gansu and Qinghai provinces, which have 1492 glaciers (760.96 km2) and 1192 glaciers (836.85 km2), respectively. The Shule River basin contains the most glaciers in both area and volume. However, the Heihe River, the second largest inland river in China, has the minimum average glacier area. A comparison of glaciers from the SCGI and revised glacier inventory based on topographic maps and aerial photos taken from 1956 to 1983 indicate that all glaciers have receded, which is consistent with other mountain and plateau areas in western China. In the past half-century, the area and volume of glaciers decreased by 420.81 km2 (–20.88%) and 21.63 km3 (–20.26%), respectively. Glaciers with areas <1.0 km2 decreased the most in number and area recession. Due to glacier shrinkage, glaciers below 4000 m completely disappeared. Glacier changes in the Qilian Mountains presented a clear longitudinal zonality, i.e., the glaciers rapidly shrank in the east but slowly in the central-west. The primary cause of glacier recession was warming temperatures, which was slightly mitigated with increased precipitation.  相似文献   

16.
基于遥感与GIS的库克苏河流域冰川变化研究   总被引:5,自引:2,他引:3  
以伊犁河上游库克苏河流域冰川为例,利用1963年地形图、2004年的ASTER数字遥感影像资料及数字高程模型,通过遥感图像处理和分析提取研究区冰川范围,并在地理信息系统技术支持下分析该地区冰川的变化情况.研究表明1963-2004年库克苏河流域冰川整体变化幅度较大,冰川表现为萎缩的趋势,2004年冰川面积、冰储量比19...  相似文献   

17.
博斯腾湖流域山区地表径流对近期气候变化的响应   总被引:4,自引:0,他引:4  
近年来,在全球和区域气候变化影响下,新疆博斯腾湖主要产流区开都河出山径流呈现异常波动,引起气候变化研究的关注.鉴于产流区复杂地形和径流补给特征以及传统观测资料的不足,借助雷达、微波及可见光等多源遥感数据从山区降水、积雪和冰川等方面与出山径流变化关系进行比较来揭示径流突变原因.结果表明,产流区平均径流深与降水量关系的转变是引起出山径流异常波动直接原因;进一步的冰川变化分析显示,径流深的波动主要由冰川融水径流变化引起:20世纪80年代中期后的温度上升加速了山顶冰川消融,导致1987~2002年的径流增加和湖泊水位升高;1984~2000年间,流域山顶冰川面积消退近40%,随着分布在较低海拔,对温度升高最敏感的中小冰川的消失,冰雪消融带来的径流增加效应开始减弱;2002年后,在流域气温、降水等变化并不显著的情况下,出山径流量却急剧降低,反映了特定冰川分布条件地区在气候变暖中融水径流先升后降的现象.  相似文献   

18.
Presented are the results from investigating the cenotic structure, structural-dynamical characteristics and spatial differentiation in vegetation of taiga geosystems in the south of the Lena-Katanga plateau of the interfluves between the Lower Tunguska and Nepa rivers. The 1:75 000 map for the present status of vegetation in the key area has been compiled.  相似文献   

19.
Snow deposition and redistribution are major drivers of snow cover dynamics in mountainous terrain and contribute to the mass balance of alpine glaciers. The quantitative understanding of inhomogeneous snow distribution in mountains has recently benefited from advances in measuring technologies, such as airborne laser scanning (ALS). This contribution further advances the quantitative understanding of snow distribution by analysing the areas of maximum surface elevation changes in a mountain catchment with large and small glaciers. Using multi‐annual ALS observations, we found extreme surface elevation changes on rather thin borders along the glacier margins. While snow depth distribution patterns in less extreme terrain have presented high inter‐annual persistence, there is little persistence of those extreme glacier accumulations between winters. We therefore interpret the lack of persistence as the result of a predominance of gravity‐driven redistribution, which has an inherently higher random component because it does not occur with all conditions in all winters. In highly crevassed zones, the lidar‐derived surface elevation changes are caused by a complex interaction of ice flux divergence, the propagation of crevasses and snow accumulation. In general, the relative contribution of gravitational mass transport to glacier snow cover volume was found to decrease for glaciers larger than 5 km2 in the investigated region. We therefore suggest that extreme accumulations caused by gravitational snow transport play a significant role in the glacier mass balance of small to medium‐size glaciers and that they may be successfully parameterized by simple mass redistribution algorithms, which have been presented in the literature.  相似文献   

20.
中国西部冰川度日因子的空间变化特征   总被引:16,自引:2,他引:14  
在冰川与积雪消融研究中,度日模型应用较为广泛,该模型是基于冰雪消融与气温,尤其是正积温之间的线性关系建立的。度日因子是该模型的重要参数,反映了单位正积温产生的冰雪消融量,其空间变化特征对于不同模型模拟冰雪消融过程的精度有较大影响。 本文根据中国西部不同地区数十条冰川的短期考察和观测资料,分析了西部冰川度日因子的空间变化特征,结果表明:由于青藏高原及其周围地区独特的气候和热量条件,西部冰川度日因子具有明显的区域特征。在同一冰川上,度日因子的空间变化较为明显。从冰川类型来看,与极大陆型及亚大陆型冰川相比,海洋型冰川的度日因子较大。总体看来,西部冰川的度日因子由西北向东南逐渐增大,这与中国西部冰川的气候环境变化趋势是一致的,即在干冷的气候条件下,度日因子较小;而在暖湿的气候条件下度日因子较大。  相似文献   

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