Abstract:

The Xiaojinhe basin is located in Boluo County,Guangdong,at 23°10'-23°20' N and 114°18'-114°28'E.The floristic origin of the basin is old and the flora is rich in relic and ancient types.There are 978 species of wild vascular plants belonging to 172 families and 532 genera in the area.2 new species and 1 new variety have been found,and 3 Spedes are new fecords to Guangdong.The characteristic families of the flora are Theaceae,Fagaceae,Moraceae,Rutaceae and Lauraceae ect.,Most of them are of tropical-subtropical distribution.There are 173 tropical genera and 169 tropical-subtropical senera in the flora,accounting for 35.2% and 34.4% of the genus total in the basin,respectively.Geographical elements of the flora are complex and varied.They may be divided into 14types and 13 subtypes,in which Pantropic element (32.7%) is the largest part of the flora,tropic element ranges the second,and Asia element (17.8%) and the old world tropic element (11.4%) the third Compared with 5 neighbouring florae,the Xiaojinhe flora is related closely with those of Gutian and Heishiding,and is aloof from those of Ganshiling and tonggang.The result of polar ordination method shows that the florae of the Xiaojinhe,Gutian and Heishiding belong to the same type.

Key words: Flora, Polar, ordination, xiaojinhe, Boluo, Guangdong