Abstract: By using the half-month averaged NDVI data of NASA/GIMMS with 8 km×8 km spatial resolution and the climatic data from 1982 to 2003, the temporal variation of mean annual and monthly NDVI in Tianjin area was studied, with its relations to precipitation and temperature analyzed. In 1982〖KG-*2〗-〖KG-*7〗2003, the mean annual NDVI in study area had a slight decreasing trend. A month-dependent inter-annual variation of NDVI was observed during growth season. The NDVI had an increasing trend in spring and autumn, being significant in October (P<005), whereas a decrease in summer, being significant in June (P<001). The mean monthly NDVI was non-linearly and positively correlated with mean monthly temperature and monthly precipitation (P<0001), indicating that the effects of temperature and precipitation on NDVI were season-dependent. There was an obvious difference in the effects of temperature and precipitation on NDVI among different months in growth season, and a lagged response of NDVI to the climate factors was observed.

Key words: Reproductive module, Flowering phenology, Abortion, Disanthus cercidifolius var.longipes