Plant Diversity ›› 2008, Vol. 30 ›› Issue (04): 400-404.

• Articles •

### Floristic Equilibrium Point and Its Biogeographic Significance

FENG Jian-Meng1 , 2 , XU Cheng-Dong3

1. 1 College of Life Science and Chemistry , Dali University, Dali 671000 , China ; 2 Department of Ecology, College of Environmental Science, Peking University, Beijing 100871 , China; 3 Department of Biology, College of Chemistry and Life Science, Chuxiong Normal University, Chuxiong 675000 , China
• Received:2007-10-16 Online:2008-08-25 Published:2008-08-25

Abstract: The floristic equilibrium point and its biogeographic significance are important for understanding the floristic origin, distribution , and spatial patterns of plant diversity . Based on field surveys, documented data and related case studies, the relationship between altitude and latitude at floristic equilibrium points , and its biogeographic significance are examined. The results showed a floristic equilibrium point at 2 050m elevation on Mt . Yao , northeastern Yunnan, China. The elevation of the floristic equilibrium point decreases with an increase in latitude .Mean annual temperature at different floristic
equilibrium points shows high consistency around 12 . 96±0 . 28℃ , which hints that the floristic equilibrium point reflects certain energy requirements . Below the floristic equilibrium point , the majority of the flora contains tropical and subtropical elements; above that point temperate elements are dominant. According to the relationship between altitude and latitude at the floristic equilibrium point, the theoretical north-south dividing line between the vegetation in eastern China is around 36°N . According to the mean annual temperature at the floristic equilibrium point and spatial patterns of the isotherm in eastern China, the north-south boundary of vegetation is between 34 and 35°N, on the northern slope of the Qinling Mountains, which is consistent with previous case studies .

Key words: Floristic equilibrium point

CLC Number:

• Q 948