皖西大别山多枝尖山区主要乔木树种种间联结特征

摘要

为探讨皖西大别山多枝尖山区植物群落中乔木树种间的相互关系,采用X2检验、联结系数(AC)和共同出现百分率(PC)对出现频率大于5%的30个主要乔木树种间的种间联结特性进行了分析.X2检验结果显示:在30个主要乔木树种组成的435个种对中,种间联结性显著(P＜0.05)或极显著(P＜0.01)的种对有23个,其中,正联结种对有15个,负联结种对有8个.AC值分析结果显示:具有明显正联结性(AC≥0.4)的种对有20个,仅占种对总数的4.6%;而具有明显负联结性(AC＜-0.6)的种对有113个,占种对总数的26.0%.PC值分析结果显示:PC值在0.6以上(PC≥0.6)的种对有22个,占种对总数的5.1%;PC值低于0.2(PC＜0.2)的种对有271个,占种对总数的62.3%.3个指标的分析结果均表明:该区域植物群落主要乔木树种间具有明显正联结性的种对较少,大多数树种的种间联结较松散;物种生态习性、群落演替阶段和人为活动等因素是造成这一特性的主要原因.%In order to explore the interrelation among arbor species in plant community of Duozhijian mountainous region of Dabieshan Mountain in West Anhui, the inter-specific association characteristics among 30 dominant arbor species with more than 5％ occurrence frequency were analyzed by X2-test,association coefficient (AC) and percentage of co-occurrence (PC). The X2-test result shows that in 435 species pairs composed of 30 dominant arbor species, there are 23 species pairs with significant (P＜0.05) or highly significant (P＜0.01) associations, in which, 15 species pairs are positive associations and 8 species pairs are negative associations. The analysis result of AC value shows that there are 20 species pairs with obviously positive associations (AC ≥ 0. 4 ), which only accounts for 4.6％ of total number of species pairs. While there are 113 species pairs with obviously negative associations (AC＜-0.6), which accounts for 26.0％ of total number of species pairs. The analysis result of PC value shows that PC value of 22 species pairs is above 0.6 (PC≥0. 6), accounting for 5.1％ of total number of species pairs. While PC value of 271 species pairs is below 0.2 (PC＜0. 2), accounting for 62.3％ of total number of species pairs. All of analysis results of three indexes indicate that the number of species pairs with obviously positive associations is a few among dominant arbor species in plant community of this region, and species association among most species is loose. And the main reasons for causing the interspecific association characteristics are ecological habits of species, community succession stage and human activity.