Shanghai, the largest city of China, is situated at the south bank of Yangtze Esture (30°42'-31°48'N, 120°52'-122°16'E).It covers an area of 6341 square kilometers.The annual average temperature and rainfall are 15.8℃ and 11 45.1mm respectively.There are 919 species of seed plants belonging to 134 families and 510 genera in Shanghai.According to the geographical distribution of spermatophytic genera, tyey may be divided into 15 types of geographical elements, which are mostly Pantropic (27.8%).Northe Temperate (21.6%) and East Asia (11.9%).The nature vegetation of Shanghai consists mainly of evergreen broadleaf forest.mixed broadleaf forest and wetland vegetation.The different types and the distribution pattern reflect the climate.characteristics of the transition area from middle subtropical to north subtropical and the trait of the natural environmemt of Shanghai, meanwhile, its current sitiuation also shows the change of the nature vegetation by human pressure.As the special ecosystem and a nature history heritage of Shanghai, forest vegetation is needed to be protected at Dajinshan Island and She Shan.The vegetation of Shanghai can be divided into two vegetation zones: the middle subtropical evergreen broadleaf forest and north subtropical mixed broadleaf forest.