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东亚－北美间断分布区的木本植物种类，初步统计共有３４科４９属９７５种，其中东亚地区７３０种，占总数的７５％，北美地区２４５种，占２５％，说明东亚种数远多于北美，估计本间断分布区中属的总数为全世界诸多洲际间断分布中极为丰富的类群。东亚－北美间断分布区有如此众多属存在的原因有三，一是地质变迁，二是气候变化，三是地史悠久。东亚－北美间断分布区中约有１８个属的现代分布中心在东亚，６个属在北美。东亚与北美主要有两个植物气候型，大陆西岸气候型（地中海气候型）的属不多，在东亚引种成功率不大，大陆东岸气候型的较多，在东亚引种成功率较高
The species of woody plants in the intermittent distribution area of East Asia to North America are preliminary classified into 34 families, 49 genera and 975 species, of which 730 species in East Asia accounted for 75% of the total, and 245 species in North America accounted for 25%, indicating that the species in East Asia far exceeded North America, it is estimated that the total number of genera in this disjunct distribution is extremely rich in many intercontinental discontinuities throughout the world. There are three reasons why there are so many existing distribution gaps in East Asia and North America. First, geological changes, second, climate change, and third, long history. There are about 18 modern distribution centers in East Asia-North America intermittent distribution in East Asia and 6 in North America. There are mainly two plant climate types in East Asia and North America. There are not many climate types in the western coast of the continent (Mediterranean climate type), small success rates in East Asia, more climatic types on the east coast of the continent, and a higher success rate of introduction in East Asia