本文运用RS和GIS,基于航空相片、地形图和遥感影像数据分析了近50a来黑河流域冰川资源变化特征。研究表明,1950s/1970s-2003年,该流域的335条冰川总面积缩小了29.6%,平均每条冰川缩小0.10km^2,冰川末端平均后退258m,退缩比率达31.0%,且黑河干流以西的冰川面积缩小及末端退缩幅度均强于干流以东。分析认为,气温显著升高是黑河流域冰川快速萎缩的主导因素。与我国西部其它地区冰川变化相比,黑河流域冰川面积缩小幅度明显较大,且祁连山东、中、西段冰川变化存在显著的区域差异性,这是区域气候差异、冰川规模等因素综合作用的结果。
The Heihe River basin, located in the middle part of the Qilian Mountains, is the second largest inland river basin across the arid area of northwestern China, east to the headwaters of Xidahe of the Shiyang River, west bounded by the Heishan and Shulehe, and the upper reaches almost across the Hexi Corridor. Glaciers, acting as a huge alpine reservoir that regulates annual runoff, are considered a reliable water source for oasis, benefiting the sustainable development of the environment, industry, and agriculture in this region. During the past decades, glaciers in the Heihe River basin have been experienced rapid shrinking due primarily to climate change. Impacts of the glaciers shrinkage on water resources have drawn much attention. Using the image interpretation method provided by World Glacier Monitoring Service (WGMS), historical data were retrieved for comparison with remote sensing images in order to reveal changes in glaciers in the Heihe River basin during the past 50 years. To compare recent changes in the glacier areas, 5 scenes of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images with spatial resolution of 15 m for visible and near-infrared bands acquired from June to September in 2003 and 24 topographic maps (1:50 000) derived from aerial photographs acquired during 1956-1978 (18 in 1956, 1 in 1957, 3 in 1966, and 2 in 1978) by the Chinese military geodetic service were jointly used and comprehensively analyzed. It is found that from the 1950s/1970s to 2003, the total area of the investigated glaciers (335) was reduced by 29.6%, with a mean reduction of 0.10 km2 for the individual glacier. The glaciers retreated by 258 m at a rate of 31.0%. The glacier changes exhibited obvious spatial differences, indicating that the reduction rate of glaciers to the west of the mainstream of the Heihe was larger than the east. In addition, rapidly rising air temperature is likely the major factor causing the shrinkage of the glaciers in the Heihe River basin. Compa