基于对山西陵川县境内野生南方红豆杉群落的样地调查,采用总体相关性VR检验、Pearson相关系数、Spearman秩相关系数和生态位测度方法,在群落尺度上对南方红豆杉群落的种间联结性和生态位特征进行了研究。结果显示:(1)南方红豆杉(Taxus chinensis(Pilger)Rehd.var.mairei(Lemee et Levl.)Cheng et L.K.Fu)、荆条(Vitex negundo L.var.heterophylla(Franch.)Rehd.)、鹅耳枥(Carpinus turczaninowii Hance)、连翘(Forsythia suspensa(Thunb.)Vahl)和三裂绣线菊(Spiraea trilobata L.)的重要值和生态位宽度较大,为群落中的建群种和优势种;(2)物种间生态位重叠指数总体偏高,种间竞争较强,尤其是南方红豆杉与其他物种之间;(3)群落总体呈显著负联结,大多数种对间呈中性关联(χ2〈3.84,P〉0.05);(4)群落中物种间的Pearson相关系数、Spearman秩相关系数与生态位重叠指数之间表现为极显著的正相关(P〈0.01),而生态位宽度与生态位重叠指数之间未表现出线性关系,即物种间的竞争关系随种间关联性的增大而增强,而与生态位宽度没有直接关系。本研究可为保护和利用本区现有野生南方红豆杉资源提供合理的理论支撑。
Based on sample investigations of Taxus chinensis( Pilger) Rehd. var. mairei( Lemee et Levl.) Cheng et L. K. Fu communities in Lingchuan County,Shanxi Province,interspecific correlation and niche characteristics were studied by overall correlation test VR,Pearson correlation index,Spearman rank correlation index,and Niche measurement. Results showed that:( 1) Taxus chinensis( Pilger) Rehd. var. mairei( Lemee et Levl.) Cheng et L.K. Fu,Vitex negundo L. var. heterophylla( Franch.) Rehd., Carpinus turczaninowii Hance, Forsythia suspensa( Thunb.) Vahl,and Spiraea trilobata L. were constructive or dominant species,and had higher importance values and broader niche breadths in the community;( 2) Higher niche overlap between species meant stronger interspecific competition,especially between Taxus chinensis var. mairei and others;( 3) Whole associations in the community showed significantly negative correlations,and most species pairs were neutrally associated;( 4) BothPearson and Spearman rank correlation indices showed significantly positive correlations with niche overlap. However,there was no direct linear correlation between niche overlap and breadth. In other words, interspecific competition was strengthened with increasing interspecific correlation,but was not directly related to niche breadth. This study provides reasonable and theoretical support for the protection and utilization of natural resources of Taxus chinensis( Pilger) Rehd. var. mairei( Lemee et Levl.) Cheng et L.K. Fu in this region.