关于地区间植物区系亲缘关系研究方法问题讨论

A Discussion to Methods Used in Studies on Floristic Affinities between Regional Floras in China

属的分布区类型组成(谱)中各类型所占百分比的类似性不能实质性反映各地区间植物区系的亲缘,因为亲缘关系疏远的不同分类群(属)可以有同样的分布区类型。植物属的分布区类型组成的类似性只反映了不同地区植物区系各地理成分的比例关系的类似性,并非直接的亲缘关系。地区植物区系之间的亲缘关系应是指它们的分类群的类似性,即血缘或共同起源关系,通常是由它们共有的植物科、属、种相似性系数,特别是其共特有分类群相似系数来反映的。

The distribution types of Chinese seed plants at generic level were documented by Z. Y. Wu and 15 areal-types were recognised. Following Wu＇s documentation, areal-types of regional floras from China have been broadly studied. A recent paper suggests a method, which defined floristic affinities by the similarities of composition of areal-types of compared regional floras. This method could not be accepted for defining floristic affinities between regional floras because the similarities of composition of areal-types do not necessarily correspond to floristic similarities. The same generic areal-type can be composed by different genera from different plant families. Similarities of composition of areal-types between compared regional floras do not necessarily represent their floristic similarities. Floristic affinity could be defined by resemblance coefficients of species, genera and families, especially those of endemic ones common to these regions, between the compared regional floras.