聚宝山郊野公园乔木层优势种群生态位特征

Niche Characteristics of Dominant Tree Species in the Jubao Mountain Suburb Park in Nanjing

基于对南京聚宝山郊野公园的样地调查,以不同生境的样地作为资源位,以物种重要值作为资源位的状态指标,运用Levins和Hurlbert生态位宽度指数、Pianka生态位重叠指数和Schoener生态位相似比例指数,测定并分析乔木层13个优势种群的生态位特征。结果表明:1Levins和Hurlbert 2种生态位宽度指数测定结果差异不大,均表明朴树、黄连木和短柄枹具有较大的生态位宽度,对群落结构和功能起着决定作用;213个优势种群间生态位重叠值>0.500的仅有1对,生态位重叠的程度不大,表明各主要树种之间竞争并不激烈。主要树种间生态位相似比例<0.2000的占总对数(78对)的71.8%,生态位相似比例也较小,各主要树种对资源利用的相似程度较低。综合分析表明,聚宝山郊野公园乔木层各主要种群间竞争不激烈,关系较缓和,群落处于相对稳定的状态。

Using the sample plots in different environmental types as resource states,the important values of species as the state indexes,we analyzed Levins and Hurlbert for niche breadth,Pianka＇s niche overlap and Schoener＇s similarity of 13 dominant tree species in Jubao Mountain Suburb Park of Nanjing based on the sample plot investigation. The results showed that： 1The Levins and Hurlbert niche breadths values had few differences. Both of them suggested that Celtis sinensis,Pistacia chinensis and Quercus glandulifera var. brevipetiolata had wider niche breadth than others with Levins（ Bi） and Hurlbert（ Ba） values being 1. 671 and 0. 536,1. 552 and0. 391,1. 394 and 0. 253 respectively. These tree species all played decisive roles in the community structure and function. 2Only 1set of 13 dominant tree species had niche overlap values greater than 0. 5,the low niche overlap found in this study suggested less fierce interspecies competition in the Jubao Mountain Suburb Park. Of the 78 species pairs,71. 8% were lower than 0. 2,the low niche similarity suggested less similarity of resource utilization between the dominant tree species. Comprehensive analysis showed that the competition among dominant tree species was not fierce,representing a relativeiy stable community in Jubao Mountain Suburb Park.