Analyzing temporal and spatial variation in evergreen needleleaf forest phenology using remote sensing data

利用MODIS卫星资料，分析了北海道大雪山东部和卡努马近郊万年青针叶林物候的时空变化。从GRVI（绿色红色植被指数）数据的时间变化和Logistic模型拟合，物候过渡日期（开始变绿，成熟，衰老和休眠）检测。结果表明，卡努马郊区12年（2001-2012年）的绿化起始值平均为DOY 92，大雪山东部为DOY 130。两个研究区的生育期相差约100天。在两个研究区，绿化开始与春季温度呈负相关。

This study analyzed temporal and spatial variation in evergreen needleleaf forest phenology in eastern Taisetsu Mountain, Hokkaido and in the suburbs of Kanuma, Tochigi, using the MODIS satellite data. From temporal variations in GRVI (Green red vegetation index) data and logistic model fits, phenological transition dates (onset of greenup, maturity, senescence and dormancy) were detected. Results show that mean value of greenup onset for 12 years (the year 2001-2012) in the suburbs of Kanuma was DOY 92, and that in eastern Taisetsu Mountain was DOY 130. Difference in growing periods between two study areas was 100 days approximately. Negative relationships were found between the greenup onset and spring temperature in two study areas.