【作者】 张慧；

【导师】 李忠勤；

【作者基本信息】 西北师范大学 ， 地图学与地理信息系统， 2015， 硕士

【摘要】 近年来气候变化所引发的资源环境问题已日益在全球范围内受到广泛关注。冰川作为气候变化最敏感、最直接的信息载体,不仅是气候变化的重要驱动因素,而且在水资源利用、海平面上升、冰川灾害防治等方面担任着重要角色。奎屯河流域位于新疆天山北麓中部、准噶尔盆地的西南边缘,是天山北坡经济带的主要水源地。由于奎屯河属雨水与冰川融水混合补给型河流,因此加强该流域冰川变化的监测与研究对于下游地区水资源的合理利用、社会经济的可持续发展、减灾防灾等都具有重要意义。本文以天山奎屯河流域冰川为研究对象,基于RS与GIS技术,利用野外实测数据、地形图数据、遥感数据及气象数据等,对奎屯河流域冰川变化特征进行了研究。主要得到了以下结论:(1)1964~2014年奎屯河流域冰川总面积减少了约64.1 km2,面积缩减率为31.9%。除面积<0.1 km2的冰川外,面积在0.1~0.5 km2,0.5~1 km2,1~2 km2,2~5 km2,5~10 km2的冰川在面积和条数方面均有不同程度的减少,其中损失最多的是面积在5~10 km2的冰川,最少的是面积在1~2 km2的冰川,表明在气候变暖的背景下,该流域冰川普遍退缩,其中一些大冰川在退缩过程中分解成中等面积的冰川或是更小的冰川,从而使得小冰川的条数和面积均有增加。两次冰川编目期间(1964~2009年),各朝向冰川面积缩减率从高到低依次为NW、SE、SW、W、E、S、N、NE。各朝向冰川条数变化方面,只有北与东北向冰川的条数是增加的,其他各朝向均有不同程度减少,但是南向冰川变化的幅度相对较小。通过对流域冰川末端海拔的统计与分析发现,冰川末端海拔主要分布在3200~3800 m。随着冰川消融与退缩,流域冰川末端海拔整体上有一定幅度的上升。1964~2014年奎屯河流域冰川总储量减少了约4.11 km3,年均亏损约0.082 km3,亏损比例达37.2%。(2)1964~2014年哈希勒根51号冰川面积共减小了约0.32 km2,面积缩减率为21.6%,且加速退缩趋势显著。1964~2010年哈希勒根51号冰川平均厚度减薄了约10 m,年均减薄约0.22 m;冰川储量亏损了约0.024 km3。1964~2014年哈希勒根48号冰川面积共减小了约0.88 km2,面积缩减率为14.4%;储量亏损了约0.085 km3,亏损比例为18.2%。野外考察发现,近年来该冰川冰温有所上升。经对比分析发现,受冰川规模与类型的影响,哈希勒根51号冰川消融速率要高于哈希勒根48号冰川。(3)应用分形理论研究奎屯河流域冰川周长与面积之间的关系,并对其空间结构稳定性进行分析发现,1964~2014年奎屯河流域冰川空间结构稳定性趋于下降,表明未来该流域冰川可能仍将保持较高的消融速率。通过对气象资料的分析发现,气温升高造成的冰川物质亏损大于同时期降水带来的补给是该流域冰川消融的主要成因。(4)与天山其他区域的监测冰川相比,哈希勒根51号冰川消融相对较慢,分析发现造成不同区域间单条监测冰川变化差异的原因是复杂的。除了受到区域间气候环境差异的影响外,冰川规模、类型、形态特征等多个因素也对冰川消融速率有影响。对比同时段天山其他区域的相关研究,发现奎屯河流域冰川面积缩减率相对较高,且冰川面积与储量变化率均高于两次冰川编目期间天山地区的整体水平。通过对区域间气象资料的比较与分析发现,奎屯河流域年均气温相对较高,但年均降水量却相对较少,表明区域间的气候差异是造成该流域冰川消融相对较快的主要原因。此外,还受该流域平均冰川面积较小,小冰川与悬冰川数量众多等因素的影响。(5)受气温上升的影响,奎屯河流域冰川加速消融使得1987~2009年的冰川融水量增加了约0.9×108 m3,在河流多年平均径流量中所占比重上升了13.7%。可见,在气候变暖的背景下,该流域冰川融水对河流径流的调节作用有所增强。更多还原

【Abstract】 Resources and environment problems caused by global climate change have drawn widespread attention in the global scope increasingly. As the most sensitive and direct carrier of the information on climate change, glacier is not only an important driving factor of climate change, but also play an important role in the utilization of water resources, sea level rise, glacial disaster prevention and so on. Kuytun River Basin is located in the north slope of the central Tianshan Mountains, the southwest margin of Junggar Basin, which is the main water source of the northern slope of Tianshan economic belt. Due to the Kuytun River is mainly supplied by glacial meltwater and precipitation, so strengthen glacier change monitoring and study is of great significance to the sustainable utilization of water resources, development of social economy, reduction and prevention of natural calamity and so on in the downstream area.Glaciers in Kuytun River Basin of Tianshan Mountains were chosen as research object, based on the GIS and RS technology, the variation characteristics of glaciers were analyzed,using field measured data, topographic data, remote sensing data, meteorological data, etc. The main results are as follows:(1) The total area of the glaciers in Kuytun River Basin reduced by 64.1 km2 from 1964 to 2014. The ratio of reduction was about 31.9%. In addition to the glaciers whose area<0.1 km2, the number and area of the glaciers whose area was 0.1~0.5 km2,0.5~1 km2,1~2 km2,2~5 km2 and 5~10 km2 have reduced all in different degree. The glaciers whose area was 5~10 km2 lost most, area was 1~2 km2 lost least, which indicated that glaciers has shrunk generally in the context of climate warming, and some large glaciers decomposed into medium or smaller glaciers, making the number and area of small glaciers increased.During the investigation of First Glacier Inventory and Second Glacier Inventory of China, the rate of area reduction in different aspect from high to low was NW, SE, SW, W, E, S, N and NE from 1964 to 2009. The number of the glaciers only in the north and northeast aspect was increased, the other aspects were all decreased in different degree, but the glaciers in the South aspect changed slightly. Through the statistics of the glacier terminal elevation, the terminus of glaciers in Kuytun River Basin was mainly distributed in the elevation of 3200~3800 m. With the melting and retreat of glaciers, glacier terminal elevation rose on the whole. The total ice volume of the glaciers in Kuytun River Basin reduced by 4.11 km3 with annual loss of 0.082 km3, and the ratio of loss was about 37.2% from 1964 to 2014.(2) The area of Haxilegen Glacier No. 51 totally reduced by 0.32 km2, the ratio of reduction was 21.6% from 1964 to 2014, showing obviously accelerated melting trend. The average ice-thickness of Haxilegen Glacier No.51 thinned about 10 m with annual reduction of 0.22 m; ice volume decreased by 0.024 km3, the ratio of loss was 14.4% during the years of 1964~2010. From 1964 to 2014, the area of Haxilegen Glacier No. 48 totally reduced by 0.88 km2, the ratio of reduction was 14.4%; ice volume decreased by 0.085 km3, and the ratio of loss was 18.2%. And the fieldwork found that its ice temperature has increased in recent years. By comparison, the ablation rate of Haxilegen Glacier No.51 was higher than Haxilegen Glacier No.48, influenced by type and volume of the glacier under the same background of climate warming.(3) In order to study the relationship between glacier area and perimeter, fractal theory was applied. And based on the stability analysis on spatial structure of the glaciers in Kuytun River Basin, we found that the spatial structure stability of glaciers tended to decline in 50 years, showing that its ablation rate was likely to remain high in future. According to the analysis of meteorological data, the glacial mass loss caused by temperature rise was greater than the recharge from precipitation was the main reason of glacier retreat.(4) Compared with the other monitoring glaciers in Tianshan Mountains, the ablation of Haxilegen Glacier No. 51 was relatively slow. After the analysis found that the causes of regional differences in the variation characteristics of single monitoring glacier was complex. In addition to the affection from regional differences in climate and environment, the volume, type, shape characteristics of glaciers and other factors also have impacts on the ablation. Compared with the related studies in other areas of Tianshan Mountains, we found that Kuytun River Basin belonged to the zone in which the ablation of glaciers was relatively fast, and the rate of area and volume change were both higher than the whole level of Tianshan Mountains.Through the comparison of meteorological data found that the annual average temperature in Kuytun River Basin was relatively high, but the average annual precipitation was relatively less. Therefore the regional difference in climate change was also the main reason for the relative fast ablation of the glaciers in Kuytun River Basin. Besides, its average area of the glaciers was smaller, below the average of Tianshan Mountains, and small and hanging glacier existed numerously also had impacts on it.(5) Affected by rising temperatures, the glacier ablation in the Kuytun River Basin making its glacial meltwater increased by about 0.9×108 m3 during the years of 1987~2009, and its proportion in the annual average runoff rose 13.7%. Therefore, under the background of climate warming, the regulation of glacial meltwater on runoff has been enhanced.更多还原