Ecology and biogeography of the limestone vegetation in southern Yuynnan, SW China / Zhu Hua.

Título equivalente em chinês

The forest on limestone in southern Yunnan, tropical southwest China, were inventoried and plotted. Three main vegetation types and pertaining to six formations, as well as nine communities, were recognized and described in detail with enumeration of forest profile and species composition. Physiognomy and species area ratios were analyzed. Species diversity was discussed with Shannon - Wiener indexes for each forest formations. Floristic composition was enumerated and biogeographical affinity was discussed too. The limestone forests were characterized by phanerophytes, which make up c. 78% of total species, and the leaf - size class of mesophylls, which make up 75% of total tree species. Comparison between the limestone seasonal rain forests and the ones on non - limestone reveals that the limestone seasonal rain forests has lower species diversity index value per unit area but higher community diversity than the rain forest on non - limestone. Ecological species groups were discerned based on field observation, of which the species exclusive to the limestone make up 10% and the preferents make up c. 12% of the total limestone flora. From these limestone forests, 1394 vascular plants species belonging to 640 genera and 153 families were recorded. Based on the study of their distributions, twelve geographic elements at the generic level and nine at the specific level were recognized. About 90% of the genera and more than 90% of the species were tropical; furthermore, 35% of the genera and 65% of the species have tropical Asian affinities. In a comparison with some regional floras from southern China and tropical Asia, it was revealed that the limestone flora has closer affinity to tropical floras. The flora is thus tropical and part of the tropical Asian flora at its northern margin.