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专题：昆明植物所硕博研究生毕业学位论文第一作者的第一单位第一作者单位通讯作者单位资助项目：Tibetan Plateau is one of the most sensitive areas to global climate change. The response of alpine ecosystem to climate change becomes a hot topic of scientific research. Plant phenology is best indicator of climate change. It will be meaningful to look at the response of alpine ecosystem to climate change from the plant phenology point of view. However, phenology research is still very weak on the Tibetan Plateau, and the ground observations are also very limited. Therefore, study on the growing season change and relation with temperature and precipitation will be scientifically and practically meaningful.In this study, we studied the interannual change of NDVI, temperature and precipitation and their correlation. Then the growing season on the Tibetan Plateau was simulated using both the slope method and NDVI ratio method. By comparing the results with ground observation, the NDVI ratio method with certain threshold was selected. Growing season from 1982-2006 was simulated with the selected method and then the spatial and temporal distribution of growing season was analyzed. Finally, we used multi-regression to derive the relation between growing season, temperature and precipitation. Some main conclusions were drawn from this study. NDVI ratio method performs better in simulating the growing season than slope method. The final thresholds selected for simulating the start and end dates of growing season are 0.2 and 0.6, respectively. Both the mean NDVI in May and June and beginning dates of growing season of meadow and steppe shows non-linear trend from 1982 to 2006. However, the beginning dates of growing season of meadow and steppe before 2000 display significant advance trend(0.48 d yr-1 and 0.62d yr-1,respectively), but delay after 2000；the end dats of meadow shows no significant trend during 1982 and 2000,but trend of the end dats of steppe is significant(0.52 d yr-1)；the lengths of growing season of meadow and steppe become longer before 2000(0.49d yr-1 and 0.55 d yr-1,respectively), then become shorter afterwards. Relation between temperature and precipitation with beginning dates of growing season is more significant than with end dates. The significantly rising temperature in winter delay the beginning dates of growing season because of the reduction of chilling requirement. Increase of spring temperature and precipitation promotes early beginning dates of growing season. The end dates of growing season are early due to the increase of temperature in July and August, but are late when temperature in September and precipitation from May to September increases.Finally, we figure out the shortcoming of the study and recommend possible way to solve the problem and more detailed future work is required.

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