摘要
Extreme weather events were analyzed based on the meteorological data from the year of 1967 to 2007 for Yamaguchi, Japan. The responses from landscape trees were also investigated mainly by the analysis of image pixel and spectral reflectance, Results show that after the dry, hot and windy summer in 2007, many landscape trees in Yamaguchi City tended to respond the extreme weather events by re- ducing their leaf surface area and receiving less radiation energy. Premature leaf discoloration or defoliation appeared on some landscape tree species and leaf necrosis occurred on tip and margin of many Kousa dogwood （Comus kousa） trees at unfavorable sites. Described by image pixel analysis method, the leaf necrotic area percentage （LNAP） of sampled dogwood trees averaged 41.6% and the sampled Sasanqua camellia （Camelia sasanqua） tree also showed fewer flowers in flower season of 2007 than that in 2006. By differential analysis of partial discolored crown, it presented a logistic differential equation of crown color for sweet gum （Liquidambar styraciflua） trees. It suggested that the persistent higher temperature and lower precipitation could be injurious to the sensitive landscape trees at poor sites, even in relative humid area like Yamaguchi.
极端天气事件为 Yamaguchi 从 1967 ～ 2007 的一年基于气象学的数据被分析，日本。从风景树的回答主要被图象象素的分析也调查并且光谱反射。结果证明在在 2007 的干燥、热、多风的夏天以后， Yamaguchi 城市里的许多风景树趋于由减少他们的叶表面区域并且收到更少的放射精力回答极端天气事件。早熟的叶褪色或落叶在某风景树种类上出现了，叶坏死发生在许多 Kousa 山茱萸(角 kousa ) 的尖端和边缘上在相反的地点的树。由图象象素分析方法描述了，取样的山茱萸树的坏死的区域百分比(LNAP ) 平均的叶 41.6% 并且树也显示出的取样的 Sasanqua 山茶(Camelia sasanqua ) 在 2007 的花季节的更少花比那在 2006。由部分变色王冠的微分分析，它为香甜的口香糖(Liquidambar styraciflua ) 介绍了王冠颜色的一个逻辑微分方程树。它建议坚持的更高的温度和更低的降水能对在差的地点的敏感风景树有害，甚至在象 Yamaguchi 一样的相对潮湿的区域。
作者简介
WANG Fei （1959-）, researcher in Shandong Forestry Research Institute, China, mainly engage in the study in the filed of ecophysiology Of trees and shrubs.Corresponding author： WANG Fei; Email：wf- 126@ 126 .com
