| As the highest-altitude region of the world, Tibetan Plateau is a unique geographical unit, due to its unique geographical features; the research about landscape in this region is very weak and is very imbalance in extent. Nowadays, as the rapid development of science and technology, Remote Sensing and Geography Information System have offered the main data sources and technological means for studying global changes, and it is also an important advanced and convenience way to landforms study especially for the difficult areas even though the using of this means has constrained now by a number of factors. In addition in the annual report of the United Nations Environment Program, it has pointed out that the Tibetan Plateau is the region in the mid-latitude regions of the world where the modern glaciers most developed, and the retreating of glaciers in Tibetan Plateau and its surrounding areas has been referred especially. Lake is a natural complex, and connected the comprehensive effects of the atmosphere, biosphere, soil and terrestrial water. Its formation and vanish, expansion, contraction and correlative evolution of ecological environment all caused by the world's, regional and Local tectonic and climatic events together. So the study about changes of glaciers and lakes in a typical basin and their response to climate change is indispensable in global change research, and by which the models of glacier changes in response to climate change and regional water balance can be established, the analysis about effect of glaciers'changes to water in western China also can be made. So this study has great theoretical and practical significance in comprehensive assessment of climate change, revealment of global climate change, and forecasting climate change.Taking the Mapam Yumco Basin of Xizang autonomous region as a case and on the basis of RS and GIS technology, the paper extracted the thematic information of the glacier landforms, then analyzed the changes in glacier and lake and compared the differences between the continental glacier region and marine glacier region. This study is supported by the"Talent Project"and Innovation Project (KZCX3-SW-339) of Chinese Academy of Sciences, National Basic Research Program of China (2005CB422004), National Natural Science Foundation of China (40401054) .The main contents and results of research are as following:1. Using the techniques of RS and GIS, the paper analyzed and drew the maps of basic elements and types of landforms in the Mapam Yumco Basin. The morphological-genetic classification of landforms in Mapam Yumco Basin have been made, and the geomorphologic structure map of the region been drew according to the combinational characteristics of relief fluctuations, altitude, formation, forms, slope and aspect.2. For this study we used topographic maps of 1:50000 scales published in 1974, the landsat TM data of 1990, the landsat ETM+ data of 1999 and ASTER data of 2003 on Mapam Yumco Basin. For the data analysis, a flow chart of processing steps was developed. The steps include scanning historical maps and downloading the images, reunifying same coordinate system, coregistration, orthorectification, co-registration, mosaic, and digitizing the glacier and lake outlines. To generate"the time and space complex graph form 1974 to2003 on Mapam Yumco Basin"we used the means of Geographic Information Tupu. Based on this, we analyzed the changes in glacier and lake during the 30 years.3. The glaciers in Mapam Yumco Basin were retreating since 1974.The retreated area of glaciers from 1974 to 2003 is about 7.27 km2 , or 6.77% of the total area, the average retreat rate is 0.24 km2 a-1. It proves that the glacier's melt rate on sunny side is faster, and the small glaciers which have steeper slope have greater melt.4. The change of lakes area was obvious during 30 year and showed a trend of reduction early and increase later. Many small lakes disappeared. The rate of lake shrinkage were changing smaller and smaller constantly, even from 1999 to 2003 it showed an tendency of extending in area of lakes. But generally speaking, the change in lakes area from 1974 to 2003 was characterized by reducing, and the retreated area was 37.58 km2, or 4.81% of the total area, the average retreated rate is 1.25 km2 a-1. 5. From 1974 to 2003, The annual average temperature of Mapam Yumco Basin showed a trend of fluctuant rising, especially the average temperature in cool-season increased significantly, which was consistent with the global warming trends; the precipitation took on fluctuant downward trend ; the annual evaporation presented slow downward trend.6. In this basin, the main factors caused glaciers'retreat are the changes of temperature and precipitation; the changes of precipitation, evaporation and glaciers'melt dominated the lakes'area.7. Using the same information sources and technique, the paper studied the situation of glaciers and lakes in Ran Wuco Basin in where marine glaciers developed. Then an analysis of contrasting the changes of glacier and lake in the Mapam Yumco Basin in where the continental glaciers developed with the situation of Ran Wuco Basin has been made. The contrast result shows that the continental glaciers have slower rate of ablation, slower movement velocity, and higher altitude of the glacier's tip.
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