昆嵛山腮扁叶蜂与乔木层树种的联结性分析

Analysis of Inter-Specific Correlation of Cephalcia kunyushanica and Tree Layer Plant Species in Natural Forests in Kunyushan

【目的】明确昆嵛山腮扁叶蜂的发生与乔木层树种关联性质以及关联强度,为通过林分结构调整控制该食叶害虫提供参考。【方法】在昆嵛山林区设置的50块永久样地内进行乔木层植物调查,并基于2×2联表,应用总体方差分析、!2统计检验、Ochiai关联度指数、Dice指数、联结系数、共同出现百分率、点相关系数以及Cramer指数等指标,分别对昆嵛山腮扁叶蜂与50块样地中所有57种乔木树种种群的总体相关性、该昆虫与各树种构成的物种对之间联结性质,联结显著性以及联结强度进行测度,并计算了这些乔木植物的重要值。【结果】1)50块永久样地范围内共有7种植物为昆嵛山腮扁叶蜂的寄主,它们分别是赤松、黑松、红松、华山松、火炬松、班克松以及美加红松,其重要值之和占所有乔木树总重要值的49.1%;2)昆嵛山腮扁叶蜂与57个树种群总体存在极显著的正相关性;3)该食叶昆虫与26个物种分别构成的物种对均呈正联结关系,与另外31个物种分别构成的物种对呈负联结关系,负联结的比例高于正联结;4)该昆虫与赤松、黑松分别具有极显著(P<0.01)和显著的(P<0.05)正联结关系,与拐枣、青杨分别具有极显著(P<0.01)和显著的(P<0.05)负联结关系。【结论】筛选出昆嵛山林区范围内与昆嵛山腮扁叶蜂存在正、负联结的乔木树种各2种,为林分结构调整控制该种食叶害虫提供基础。此外,还结合野外实际观测情况,对昆嵛山林区内食叶昆虫—寄主—非寄主的分布及共存状况与原因进行分析和讨论,并对各个物种联结性联结性指数的作用和局限进行评价。由于该种食叶害虫仅出现于昆嵛山林区范围内,属于地区特有种,故而本项研究对揭示本地害虫长期以来与寄主协同互作的模式也有一定的指示意义。

【Obiective】Inter-specific association is a kind of measurement which depicts the spatial coexisting patterns of one species pair or many different species in a certain space region,and it is a statistical judgement method based on binary qualitative analysis. 【Method】Based on Square-Plot method and the 2 × 2 contingency table of species presence /absence data collected from 50 permanent plots in Kunyushan region,the VR analysis,!2-test,association coefficient,Ochiai association index,Dice association index,point correlation coefficient,Cramer index,as well as percentage cooccurrence,were used in quantitative analysis of the inter-specific correlation of Kunyushan web-spinning sawfly（ Cephalcia kunyushanica,the defoliator） occurrence and adjacent Tree layer plants of natural forests in Kunyushan region,and the importance values of those plants were also evaluated. 【Result 】 Seven species, including Pinus densiflora,P. thunbergii,P. koraiensis,P. armandii,P. taeda,P. banksiana and P. resinosa,were found to be the host of C. kunyushanica,and the summation of the importance values of the seven plants accounted for 49. 1% of the totalimportance values of all tree species. The results also indicated that there was a significant positive correlation of overall association existing among C. kunyushanica and other 57 neighboring tree species（ P 0. 01）. The result of !2-test showed positive associations for 26 species-pairs and negative associations for 31 species-pairs,and the ratio of negative pairs was higher than positive ones. Furthermore,the insect showed extremely significant positive inter-specific correlation with P. densiflora（ P 0. 01） and P. thunbergii（ P 0. 05） respectively,while negative ones were found between the insects and Hovenia acerba（ P 0. 01） and Rhus chinensis（ P 0. 05）,respectively. 【Conclusion 】According to the statistical results,we selected the four plant species mentioned above as the key species,using as future judging species of C. kunyushanica. Moreover,we discussed the reasons of spatial coexisting patterns of the specific insect herbivores-hostsnon-hosts model,and evaluated the application of each index. Given that C. kunyushanica,the specific insect herbivores,occurs only in Kunyushan region,the research would have indication to reveal the long time interaction and synergism evolution between the specialist pest and hosts.