XVI International Botanical Congess
Floristic and systematic analysis of 135 rare and endangered plant species distributing in South China's Lingnan region shows and exemplifies eight types of formation and endangerment causes, i.e., geologic, climatic, edaphic, of refuge, of natural breading, of edge effect, developed out of indigenous flora and of habitat fragmentation. Further analysis of their endemism makes three ecologic-floristic patterns recognizable, which can be described as endangerment plus regional endemism, endangerment plus local endemism, endangerment plus wide but diffused dispersal.