Abstract: Guangzhou City is a rapidly urbanizing city in China, and a constructed city with holistic planning. By using the remote sensing images of 1985, 1990, 1995, 2000 and 2004,this paper studied the 20 years spatio-temporal changes of landscape pattern in Guangzhou, and analyzed the relationships between these changes and urbanization. The landscape and class-level pattern indices of whole Guangzhou City and its five districts were compared, and the results indicated that the landscape pattern in Guangzhou had an obvious spatio-temporal variation, and an increase of diversity and fractal dimension. The landscape structural complexity and fragmentation increased gradually from 1985 to 2004, and the variation intensity and tendency varied during four comparative stages 1985～1990, 1990～1995, 1995～2000, and 2000～2004. It was a rapid development period from 1985 to 1995 in Guangzhou. The represents of ten districts varied in their spatio-temporal landscape pattern, because of the different development progress and planning motive. The urbanization of Panyu was from1990 to 2000, and its natural landscape was seriously disturbed by human activities. The represents of Conghua and Zengcheng districts were of integrative disturbance, and also, the urbanization process mainly took place during 1990-2000. In the city center consisting of 8 official constructed districts, the urbanization process happened earlier. In Huadu district, the landscape change revealed the frequent and severe human disturbance.

Key words: Lathyrus sativus, ABA, ODAP, Water stress, Active oxygen