| Climatic change characteristic by global warming has posed a great threaten to terrestrial ecosystem and sustainable development of human society. Vegetation change and its relation with environment are major concerns in global change. Transect investigation based on stations and spatially analysis could help us to detect influences of global change in different scales. Based on the biweekly dataset of NOAA/AVHRR NDVI (Normalized Difference Vegetation Index) and climatic data of China with 752 standard stations for 1982-2006, we studied the dynamic characteristics of climatic factors and vegetation activities in NSTEC using tendency test, relative, numerical simulation and model, and we also studied the effects of climatic change to sensitive index, such as vegetation phenology events (greep up, dormancy, etc.) and NDVI as spectral index as an indicator of vegetation activity. Then,12 main vegetation types in NSTEC were selected and their responses to temperature and precipitation were also analyzed using statistical models. We mainly focused on (1) Spatial grid metrological data were interpolated using software Anusplin (Ver.4.1; Australian National University, Center for Resources and Environmental Studies, Canberra, Australia). SMK test was used to analyze the trend of climate factors in both transect and biome scales. (2) NDVI of main vegetation types along the North-South Transect of Eastern China (NSTEC) were extracted using remote sensing software ENVI (ver4.3, RSI). A smooth-splin method was used to simulate and develop smooth phonological curves which were used to determine timing of main phenological events by the first derivative method. (3) Least square were used to calculate the relationship between climatic factors and NDVI in both transect and vegetation type scales.The results are:(1) Temperature increased extensively in china, especially in the middle of NSTEC where temperature increased 0.06℃per year from 1958 to 2006. But the increasing rate of temperature from 1982 to 2006 was higher than it was from 1958 to 1981, which reach to 0.25℃per year in the mid of NSTEC. Precipitation decreased in the north but increased in the south of NSTEC. Increase rate of temperature has been more and more rapidly from the last 20 years which led to drought in north but flood in south. Precipitation in northeast China and middle of Yangzi River decreased about 5～35%(3～18mm·a-1) and increased about 10～25% (4-10 mm·a-1) in southern China.Significantly increases of annual temperature were detected in regions of all vegetation type except TCTCF, and the trend was most significant in TDBF. Temperature increased in early spring, early autumn and summer which range from March to September. More than five-month warmings had been found in TCF, TDS, TG, TGS, SDBF and STCF, in comparison, there were only 1-2 months warming in TCTCF and TMS.Decreases trend of annual precipitation were found in TCTCF, TMF, TDS, TMS and TG, while monthly precipitation decreased mainly in March (TCF, TG and STCF) and September (TMF, TDBF, TDS, TMS, STG and SEBF) in temperate area.(2) Earlier onsets of green-up were found in Temperate Coniferous Forest (TCF,0.56 d·a-1), Temperate Grassland (TG,0.66 d·a-1), Subtropical and Tropical Coniferous Forest (STCF, 0.46 d·a-1), Subtropical Deciduous Broadleaf Forest (SDBF,0.58 d·a-1), Subtropical and Tropical Grassland (STG,0.89 d·a-1). Delays of dormancy were found in Temperate and Cold Temperate Coniferous Forest (TCTCF,0.32 d·a-1), Subtropical Deciduous Broadleaf Forest (SDBF,0.80 d·a-1) and Temperate Deciduous Forest (TDF,0.18 d·a-1). Prolonged growing season lengths (GSL) were also found in most vegetation types in the transect; however, these differed in their onsets dates of green-up or dormancy. Prolonged GSL in TCF (0.77 d·a-1) was caused by earlier onset of green-up, prolonged GSL in TCTCF (0.38 d·a-1) and TDBF (0.36 d·a-1) were caused by delays of dormancy and prolonged of GSL in TG (0.76 d·a-1), STCF (0.83 d·a-1), SDBF (1.4 d·a-1) and STG (1.3 d·a-1) were due to both advances of green-up and delays of dormancy. Correlations among precipitation, temperature and NDVI were analyzed to further explore the causes of phenological variation. The result showed that temperature has greater influence on variations of phonological events than precipitation. Heat gradient along NSTEC caused a phonological events gradient, i.e., a time sequence of cold temperate zone> temperate zone> subtropical zone in the onset dates of green-up and subtropical zone> temperate zone> cold temperate zone in the onset dates of dormancy and growing season lengths.(3) The increase in NDVI corresponded to an increase in temperature on the national scale, while regional variations in NDVI appeared to be related to precipitation. The NDVI trend showed a large spatial heterogeneity, possibly associated with changes in regional climate, land use and vegetation type. NDVI trend was control by temperature and precpipitation in transect scale. In biome scale, annual NDVI of TDF corresponded to temperature while TGS and STCF corresponded to both temperature and precipitation, and no significant relation were detected between NDVI and climatic factors in other type of vegetation which corresponded to variations of water and heat within the year.NDVI were most significantly related to the temperature during the preceding 4 months. Time lag of NDVI responses to temperature gradually decreased from January to April. NDVI showed a stronger correlation to temperature than precipitation in most vegetations, while vegetations in temperate and cold temperate zones showed a more closely correlation to precipitation than vegetations in tropical and subtropical zones. The responses of vegetation to precipitation were evident in TCF, TDS, TGS and TG, and it also showed a longer lag in the precipitation than in temperature.Responses of vegetation along NSTEC to global change showed regional heterogeneity with a main way of dynamics in growing season and activity, namely, variations of phonological events and trends of NDVI.
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