城市近郊构树群落主要种群种间联结及物种多样性研究

Study on the interspecific association among dominant populations and species diversity of Broussonetia papyrifera communities in suburban

为了更好地了解与利用城市边缘次生构树林,利用群落学手段,在南京仙林地区设置了20个10×10 m2样地,对该地区构树群落的种间联结关系及物种多样性进行了研究。结果表明:(1)乔木层和灌木层各自的总体关联性均成正联结;利用统计量W检验显示,灌木层总体关联性不显著,而乔木层呈显著。(2)x2检验显示,不论是乔木层或灌木层,种间显著联结的种对均较少,乔木层为4对,而灌木层为2对。(3)共同出现的高频率种对数量较少。(4)Margalef丰富度指数、Simpson指数和Shannon-Wiener指数在乔木层和灌木层的数值分别为0.308、0.638、0.649和0.676、1.548、1.870,说明群落的物种丰富度不高;乔、灌层的Pielou均匀度指数平均值仅有0.678和0.611,反映了物种的分布均匀程度不高,群落的稳定性差的特点。因此,构树群落内的大部分种对的种间联结较为松散,物种分布具有一定的独立性,群落内物种的出现与组成随机性强。

In order to know and utilize the secondary forest ofBroussonetia papyrifera distributed in suburban, 20 plots （10m× 10m） were investigated by the method of phytocoenology, and the interspecific association and species diversity were discussed. The results showed： （1） there were both positive correlations among the species-pair in tree and shrub layer, but it was just significant positive correlations among the main tree species based on the statistic test W. （2） The values of x2 test showed that there were few significant positive correlations among the species-pair, only 4 and 2 pairs in tree and shrub layer respectively. （3） The data of co-occurrence （PC） appear to provide further evidence that there were few high frequency species-pair. （4） The values of diversity index including Margalef, Simpson, and Shannon-Wiener were 0.308, 0.638, 0.649 and 0.676, 1.548, 1.870 in tree and shrub layer respectively; meanwhile, the data indicated that the richness of species was poor in the communities. The values of Pielou index were 0.678 and 0.611 in tree and shrub layer respectively, which mean that the characteristic of communities was uneven distribution and poor stability. It can finally come to the conclusion that the relationship among the species was not significant close and randomly distribution, which indicated that most of species had the characteristic of independence.