中国植被覆盖季节变化和空间分布对气候的响应--多年平均结果

THE RESPONSE OF THE VEGETATION SEASONAL VARIABILITY AND ITS SPATIAL PATTERN TO CLIMATE VARIATION IN CHINA:MULTI-YEAR AVERAGE

中文关键词:  EOF方法  植被空间分布  植被季节生长变化

英文关键词:China  NDVI  Spatial pattern  Seasonal variability

中文摘要:

      文中利用1982～1993年的12a平均归一化植被指数数据,并结合同期的温度、降水数据,运用经验正交函数分解的方法(EOF)分析了中国植被覆盖变化的时空特征及其与温度、降水气候因子的定量关系,发现在多年平均意义上,在中国大尺度研究区域,归一化植被指数所表现出的植被变化时空特征具有:(1)植被的空间分布与降水空间分布更吻合,植被季节生长变化与温度的季节变化特征更近似;(2)植被与温度在季节生长变化上存在e指数关系;与降水存在幂指数关系;(3)植被季节生长与温度存在同期相关;与降水存在滞后相关,滞后时间两旬。

英文摘要:

      With the multi precipitation, and the seasonal variability of growth represented by NDVI is well correlated with the seasonal temperature variation. (2) The exponential ‘e' relationship exists between NDVI and temperature. When the temperature is lower than some threshold value, the change of NDVI is not evident. When the temperature is above the value, the NDV I increases greatly with a rategreater than the increasing rate of temperature. In the meantime, the NDVI and precipitation have a power exponent relationship. This probably is ref lected by the follow ing facts. When the precipitation does not exceed some threshold value, the NDVI increases along with the increase of precipitation; but when the precipitation reaches or exceeds the threshold value, the precipitation no longeractsas the controlling f actor of vegetation increase. (3) The seasonal growth of vegetation in China responds to the temperature synchronically, but lags a 20-day behind the precipitation on the average.