皖南岭南山地种子植物区系分析

A Preliminary Floristic Study of Spermatophyta from Lingnan Mountain Region,Southern Anhui

岭南山地地处江南古陆北缘,是皖南山区种子植物区系成分较为丰富的地区之一。该区计有种子植物136科,553属,1185种(包括种下分类等级)。植物区系起源古老,具典型的中亚热带性质;其中以温带区系成分为多,但也有丰富的南方热带成分,表现为南北过渡之性质。有些南方热带成分还以岭南山地及其北缘附近为分布北界。因此,在区系区划上,本区应与30°N 附近以北的皖南其它区域区别开来。在植被区划上,宜将30°N 附近一线作为划分皖南境内中亚热带常绿阔叶林与北亚热带常绿阔叶——落叶阔叶混交林之分界线。

Lingnan mountain region,with the longitude ranging from 118°07′ to 118°13′E and the latitude from 29°23′to 29°28′,is l(?)ated in the south end of southern Anhui.Geologically,it is close to the north edge of the Jian- gnan ancient landmass.Its flora is relatively rich,with 1,185 species of 553 genera among 136 families.Of which are primtive and archaic compositions which imply that this region has an ancient history in floristic origin.Some tr- opical elements of Magnolia,Euchresta,Michelia,Microtropis,Uncaria,Ela- eocarpus and Lasianthus etc.have their north boundary of geographical distrib- ution within this region.A few species even extend to the line near 30°N.In addition,the typical subtropical evergreen broadleaf forest south of this line, consisting of Castanopsis,Cinnamomum,Schima,Michelia,Dalbergia,Terust- roemia and Ilex etc.,is seldom seen or not so typical,if there is any,on the other side.Therefore,it can be concluded preliminarily that the line dividing central and north subtropical zones in southern Anhui should be drawn near 30°N.This is also supported by the quantitative annyses of flcristic similar- ity.Although Lingnan Mt.region is located in the north edge of central sub- tropical zone,its flora is not only rather rich in tropical elements but also characteristic of floristic transition from tropical to temperate elements