海南桉树林林下植物多样性特点的简单相关分析

Single factor correlation analysis of diversity in a Eucalyptus plantation understory on Hainan Island

通过野外样方样地调查,在比较分析海南岛年降水量、土壤含水量和土壤速效养分氮、磷、钾的基础上,寻找影响桉树Eucalyptusspp.林下植被的关键因子。单因子相关分析结果表明:木本植物Shannon-Wiener指数(H′)和Simpson指数(D)与土壤含水量、年降水量、土壤速效氮和有效磷达到了显著相关水平,但这些因子无一与草本多样性指数H′和D达显著相关水平。造成如此差异,可能由于桉树林下灌木发育阻碍了林下草本的生长,或由于桉树林下植被演替所处阶段使然。

This research was conducted to find the critical factors that influenced diversity of Eucalyptus understory vegetation. A comparative analysis of annual rainfall, soil water content, and available soil N, P, and K using the Shannon-Wiener （H′） and Simpson＇ s （D） diversity indexes from outdoor sample-plot surveying was undertaken on Hainan Island. Results of a single factor correlation analysis showed woody plants had a significant or highly significant correlation with soil moisture （H′, P = 0.002 6; D, P = 0.002 3）, annual rainfall （H′, P = 0.002; D, P=0.005）, as well as availableN （H′, P= 0.0144; D, P=0.0253） and available P（H′, P=0.0044; D, P = 0.012 0） of the soil. However, the relationship of these factors with diversity indexes H′ and D in herbaceous plants were not significantly different. This was probably due to understory shrub development that limited herbaceous growth or due to the vegetative successional stage of the understory in the Eucalyptus plantation. [Ch, 2 tab. 15 ref.]