Global warming caused a dryer and warmer climate in the hinterland of the Qinghai-Tibet Plateau.Does it cause any responses from the plants ecology,and how?Based on field works and statistical data collected in 2002 and 2003,we basically concluded warming trend of the climate is the major reason for the succession devolution of alpine plants in the central part of the plateau.In the study area,it is specially causing a devolution from alpine Kobresia meadow to Alpine Stipa steppe at a rate of 14.2km/10a.Accordingly,the total biomass of the area is declining.With contrast to some relative researches,we basically concluded a dryer and warmer climate should take the responsibility for vegetation devolution accompanied with biomass decline in the area.Changes of the surface vegetation will be the negative factors influencing the capability of the environment self-adjustment and the development of the local economy.