Biodiv Sci ›› 2007, Vol. 15 ›› Issue (4): 408-418.DOI: 10.1360/biodiv.060307

• 论文 • Previous Articles     Next Articles

Altitudinal pattern of vascular plant species richness based on equal-area belts in Mt. Helan

Yuan Zhu1, Yuan Jiang1*, Quanru Liu2, Min Xiong3, Muyi Kang1   

  1. 1 College of Resources Science and Technology, Beijing Normal University; China Ecological Assessment Research Center at Beijing Normal University; State Key Laboratory of Earth Surface Processes and Resource Ecology (Beijing Normal University), Beijing 100875
    2 College of Life Science, Beijing Normal University, Beijing 100875
    3 Department of Ecotourism, Southwest Forestry College, Kunming 650224
  • Received:2006-12-06 Revised:2007-04-06 Online:2007-07-20 Published:2007-07-20

Abstract: Altitudinal pattern of plant species richness along an elevational gradient has often been studied by dividing the mountains into equal-elevation belts. However, comparisons of species richness among different belts with different areas is not appropriate. Based on a Digital Elevation Model (DEM) and Geographic In-formational System (GIS), we divided Mt. Helan (1,300–3,500 m) into several equal-area belts along an alti-tudinal gradient, and compared the plant species richness among them. The results were as followed: (1) The altitudinal pattern of species richness in Mt. Helan showed a unimodal shape, peaking around 2,000 m alti-tude. (2) The slope heterogeneity was the primary variable to explain the altitudinal pattern of species rich-ness. High values of slope heterogeneity could reflect the complex topographic features and diversified habi-tats within a belt, implying a favorable condition for more species to coexist. (3) The unimodal pattern of species richness might result from a combined effect of evolutionary history of vegetation, climates, topog-raphic features, ecotone, and the mid-domain effect. (4) Compared with equal-elevation belts, equal-area belts could directly eliminate the influence of area upon species richness, leading to a more reliable analyticresult, especially when the species data were accurate at all altitudinal ranges.