Abstract: In this paper, the dynamic variation of the inland lakes in the Qinghai-Tibetan Plateau was investigated based on the mapping of the lakes in 4 years (1976, 1990, 2000 and 2009) and the Landsat time series images so as to reveal the spatiotemporal variation of the lakes in the plateau under climate change in recent decades. The temporal processes and spatial patterns of change of the lakes were analyzed at drainage basin scale, and the mechanism of inland lake change was discussed from the aspects of regional climate factors and recharge water sources of the lakes. The results showed that the inland lakes in the plateau were holistically in a shrinkage during the period of 1976-1990 but in an expansion during the period of 1990-2009, and the total lake area was expanded by 27.3% during the period of 1976-2009. Considering from the spatial patterns of lake change, the lakes recharged by groundwater were in a dramatic expansion or shrinkage, but those recharged by glacial melt water were stable or in a slight expansion. Recharge water sources of the endorheic basins affected strongly the lake change rate, the change of climate factors, such as precipitation, evaporation and air temperature, could be used to explain the shrinkage or expansion of the lakes. Therefore, regional climate change is the key factor causing the dramatic change of the inland lakes in the Qinghai-Tibetan plateau, and the recharge water sources could be regarded as the main factor affecting the regional difference of lake change.

Key words: inland lake, lake area, spatiotemporal variation, endorehic basin, climate change, air temperature, precipitation, Qinghai-Tibetan Plateau