Biodiv Sci ›› 2016, Vol. 24 ›› Issue (1): 30-39.DOI: 10.17520/biods.2015207

• Orginal Article • Previous Articles     Next Articles

Responses of spatial pattern of woody plants’ basal area to topographic factors in a tropical karst seasonal rainforest in Nonggang, Guangxi, southern China

Yili Guo1,2, Bin Wang1,2, Wusheng Xiang1,2, Tao Ding1,2, Shuhua Lu1,2, Fuzhao Huang1,2, Shujun Wen1,2, Dongxing Li1,2, Yunlin He1,2, Xiankun Li1,2,*()   

  1. 1 Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin, Guangxi 541006
    2 Guangxi Youyiguan Forest Ecosystem National Research Station, Pingxiang, Guangxi 532699
  • Received:2015-07-18 Accepted:2015-11-02 Online:2016-01-20 Published:2016-06-12
  • Contact: Li Xiankun

Abstract:

Spatial patterns of aboveground biomass are important aspect of species distribution patterns, whereas the environmental heterogeneity caused by the topographical differences in the scope of local scales is the environmental basis for the formation and evolution of this pattern in natural forest systems. In this study, we examined the spatial patterns of total basal area of woody plants, to quantitatively analyze the response mechanisms of the spatial patterns of total basal area to the seven topographic factors using a generalized additive model in a fully mapped 15 ha permanent plot in a northern tropical seasonal rainforest in a karst landscape in southern China. We used the total basal area of all the individuals and each DBH class in each 20 m × 20 m quadrat as a standard to measure the value of aboveground biomass of woody plants. Results showed that the hillside had the highest total basal area but the lowest was found at the ridge of the three habitat types. The total basal area of the ridge was significantly different between the hillside and the depression. Topographic factors had definite effects on the total basal area of woody plants, with the following sequence: elevation > aspect > convexity > rock-bareness rate (RBR) > altitude above channel (ACH) > slope > topographic wetness index (TWI). All topographical factors were statistically significant with the exception of the TWI and slope showing marginally significant. The relationships between the spatial variation of total basal area of woody plants and topographic factors reflected the response mechanisms and growth strategies of woody plants in a tropical seasonal rainforest under the effects of the redistribution of soil, water and light conditions.

Key words: pattern, basal area, topographic factors, contribution rate, Nonggang Dynamics Forest Plot, tropical karst seasonal rainforest