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全球变暖与可持续发展是当今地学研究的两大主题。青藏高原作为“地球第三极”，是地球上最高、最大和最新的独一无二的自然地域单元，近50年来其变暖幅度超过北半球同纬度其它地区。青藏高原冰川在全球气候变暖背景下如何变化，冰川水资源是增多还是减少，已成为举世瞩目的重大问题。湖泊是全球环境变化的敏感区域，是全球环境变化研究的典型地区；而内陆湖泊是湖区气候与环境变化的指示器。青藏高原湖泊处于自然状态，受人类活动影响较小，能够较真实地反映气候状况，是全球环境变化的敏感区域和全球环境变化研究的理想区域。由于青藏高原冰川与湖泊区人烟稀少，自然条件恶劣，传统方法难以理想地获取冰川和湖泊的变化数据。随着遥感技术手段的发展，遥感与地理信息系统技术为探测湖泊与冰川的变化提供了有效的手段。本文选取青藏高原北部湖盆区典型流域蓬错流域与色林错流域，利用历史地形图，数字高程模型和多时相遥感数据，对研究区域内过去30余年来冰川与湖泊的现代变化特征进行分析，得到以下主要结论：（1）1970-2006年间，蓬错流域及邻近念青唐古拉山区冰川面积不断减小，由138.57 km2减少到108.61 km2，退缩速率为0.832 km2 a-1。冰川退缩速率在不同时段内各不相同；面积较小（小于1 km2）的冰川相对退缩比例大于面积较大（大于1 km2）的冰川；东南坡的冰川退缩速率大于西北坡冰川。在同一时段内，蓬错流域的湖泊总面积持续扩大，由280.82 km2增加到323.90 km2，面积扩张速率为1.197 km2 a-1。特别是蓬错发生了极为显著的面积扩张，其于1992-2006年间面积迅速扩张30.76 km2；而其它中小湖泊则经历了面积先减小后扩张的变化过程。估算冰川融水对蓬错湖面上升的可能贡献量达到5.85 m。（2）在扎根藏布流域，1970-2007年间冰川面积不断减小，由92.47 km2减少到76.99 km2，退缩速率0.418 km2 a-1。同时期流域内主要湖泊面积持续扩大，但由于流域内四大主要湖泊均为过水湖，受地形影响其面积扩张比例和扩张大小与蓬错相比较小。（3）自1969/1970年以来，色林错流域冰川持续退缩，其中位于流域西南的申扎杰岗山区的亚大陆性冰川其相对退缩比例大于位于流域东北边缘的各拉丹冬山区的极大陆性冰川。流域内的湖泊在同时期整体上呈持续扩张的态势，流域内湖泊扩张主要发生在河流入湖口处。估算1970-2000年冰川消融损失的冰储量共计8.118 km3，对色林错湖面水位上涨的可能贡献量达到4.19 m。随着湖泊的扩张，众多湖岸湿地草场被淹没，对当地牧民生产生活带来严重的影响。（4）将冰川、湖泊的变化与邻近气象站点观测资料加以比较，无论是蓬错流域还是色林错流域，气温均呈现波动上升趋势，与全球变暖的趋势一致；两地的年降水量在波动变化中略有上升；而蒸发量则表现出波动下降的趋势。两流域内的冰川变化对气候变化，特别是气温的上升响应明显。而降水的增加、蒸发的减小所引起的水量平衡变化与温度升高所引起的冰川融水的增加共同决定了区域内湖泊面积的增长。（5）本文在对藏北高原典型冰川和湖泊现代变化的遥感研究中总结了冰川、湖泊在遥感影像上的目视解译特征以及其在遥感影像波段和波段组合指数上的特征，并尝试引入地统计学纹理，结合多指标分类树法与图谱法，建立了高原冰川与湖泊变化的遥感研究方法，并在实际工作中验证了其可行性。

Global warming and sustainable development are the two focus issues on climate change today. As the "third pole", Tibetan Plateau is believed as the trigger and pioneer area of East Asian climate change. And its warming rate has outpaced other parts of the Northern hemisphere in the same latitude. How do glaciers change under the background of global warming, and whether glacier water resources are increasing or decreasing, are becoming obviously the important problems. On the other hand, the evolution of the lakes, especially inner lakes, is the indicator of climatic and environmental changes in the Tibetan Plateau. The lakes on the Qinghai-Tibetan Plateau, a sensitive regions to global change, are free from the anthropogenic activities, thus the evolution of the lakes can reflect the natural climate change honestly. The data about glacier and lake fluctuations on the Tibetan Plateau are scarce due to the difficulty to access and harsh living condition near the glacier and lake. The new space technology as satellite remote sensing can be used as an alternative way to study lake and glacier evolution as a consequence of climate change. Based upon the aero-photo topographic maps, digital elevation models, multitemporal satellite images, the authors interpreted and analyzed the changes of glaciers and lakes of the past more than 30 years in Pengcuo lake basin and Silingco basin, which are two typical basin in the Northern Tibetan Plateau. The main results are listed in the following. (1) In the Pengcuo lake basin and nearby Nyainqentanglha Range in the past 36 years, glacier area decreased from 138.57 km2 to 108.61 km2 with a speed of 0.832 km2a-1. Glaciers in southeastern part of Nyainqentanglha shrank more than those in northwestern part, and the relative retreat speed of glaciers less than 1 km2 is bigger than those larger than 1 km2. At the same time lake area in the research region increased from 280.82 km2 to 323.90 km2 with a speed of 1.197 km2a-1. Lake expansion happened mainly in Pengcuo. During 1991-2006, Pengcuo lake expanded by 30.76 km2. And the glacier melted water has contributed about 5.85m to the rising lake level of Pengcuo. (2) In the Zhagenzangbu basin, glacier area decreased from 92.47 km2 to 76.99km2 with a speed of 0.418 km2a-1 between 1970 and 2007. At the same time the area of major lakes in the research region was increasing. (3) In the Silingco basin, glaciers retreated continuously since 1969/1970. The retreat ratio of sub-continent glaciers in Xianzajiegang Mountain is greater than the ratio of extreme-continent glaciers in Geladandong Mountain. At the same time, lakes in this region expanded continuously. And the lake expansion happened mostly around the confluence of lakes and related rivers. The estimated glacier storage loss during 1970-2000 is 8.118 km3, which might cause the water level in Silingco rising 4.19 m. Many wetland and pasture near the lakes were swallowed up by expaned lakes, which affected local residents’ lives seriousely. (4) Compared with meteorological data from nearby stations, the average annual temperature in Pengcuo basin and Silingco basin fluctuated and increased, which was in agreement with the global warming nowadays, while the annual precipitation increased and the annual evaporation decreased. Glacier changes in the two basins showed that the rising temperature is the main factor of glacier retreat. The increase of precipitation, decline of evaporation and the increased glacier runoff water caused by rising temperature are the main factors of lake expansion. (5) The spectral properties of lake and glacier are discussed and a remote sensing method on the study of glacier and lake, which combines geostatistical texture, decision tree classification and map algebra together, was constructed and tested. The results show that the method is feasible.