[目的]研究神农架地区次生林主要原生树种与引进树种树干附生地衣多样性的差异,为该地区的地衣多样性保护和次生林管理提供理论支持.[方法]采用样线法调查神农架地区次生林7个原生树种和3个引进树种的树干附生地衣,运用EstimateS 9.1.0软件包计算各树种预期地衣丰富度,统计各树种地衣群落的物种组成和生长型组成,计算Shannon-Wiener指数(H)、Simpson指数(D)和均匀度指数(E)并评估单株、树种和种组水平的群落多样性特征,最后采用系统聚类法对10个树种的地衣群落进行聚类.[结果]10个树种树干地衣预期丰富度存在较大差异,且引进树种的预期地衣丰富度均值高于原生树种;10个树种的树种内地衣丰富度和树种间地衣丰富度变异均较大,但原生树种组和引进树种组间无差异;引进树种和原生树种树干地衣的优势种类存在明显差异,表现为小刺褐松萝、大哑铃孢、流苏茶渍和日本珊瑚枝4种地衣在原生树种上成为优势种,橄榄斑叶梅和裂树花则只在引进树种上成为优势种,引进树种中新出现了美国树花、裂树花和侯氏树花等地衣;不同生长型地衣在树种间的分布也存在一定差异;原生树种地衣群落的多样性指数具有锐齿槲栎最低而川鄂柳最高的特点,而引进树种组具有华山松>马尾松>日本落叶松树的趋势;原生树种地衣群落的多样性指数略高于引进树种组;10个树种的地衣群落可以聚成与优势地衣组成相关的3类,而3个引进树种分属其中一类.[结论]神农架地区次生林拥有较高的地衣丰富度;10个树种的树干附生地衣群落在物种丰富度、多样性、优势种组成、部分地衣的宿主偏好方面存在差异,说明该地区森林生态系统的树种多样性对于地衣多样性维持具有重要意义;华山松等用材树种的引进及其种群动态对该地区地衣多样性的潜在影响值得关注.%[Objective]Epiphytic lichens play an important role in maintaining biodiversity,nutrient and water cycle, also in indicating environmental quality in forest ecosystem. This paper investigated the divergence of epiphytic lichen diversity of introduced and native tree species in the secondary forests of Shennongjia Mountain.[Method] Three introduced tree species ( Pinus armandii,Pinus massoniana and Larix kaempferi) and seven dominant native trees species ( Salix fargesii, Salix wallichiana, Quercus aliena var. acuteserrata, Cerasus pusilliflora, Pteroceltis tatarinowii, Bothrocaryum controversum,Abies fargesii) were surveyed,then we estimated their expected lichen species richness with the software package EstimateS 9. 1. 0 . Lichen species and their growth form on each tree species were listed to analyze the difference of community composition among tree species. Shannon-Wiener (H),Simpson (D) and Evenness (E) were calculated to evaluate lichen community diversity at tree species level,as well at native group vs introduced group level. Finally,lichen community of 10 tree species were clustered with SPSS 10. 0 to demonstrate their similarity.[Result]Expected lichen species richness was significantly different among 10 tree species,and the expected species richness of introduced tree group was a little higher than that of the native tree group. Practical lichen species richness of 10 tree species varied moderately, there were no difference between native group and introduced group. Furthermore, the dominant lichen species of the introduced tree species differed significantly from those of the native tree species. Usnea luridorufa,Stereocaulon japonicum,Lecanora thysanophora,and Heterodermia diademata were domitant in the native tree species. In contrast,Ramalina minuscula,and Petrelia olivetorum were dominant in the introduced species. In addition, some lichen species such as Ramalina americana,Ramalina minuscula and Ramalina hossei were found only in introduced tree species,suggesting that some lichens prefer to certain tree species. Lichen community diversity index varied among 10 tree species. In the native tree group,Quercus aliena var. acuteserrata displayed the highest diversity,but Salix fargesii displayed the lowest diversity,while the introduced tree group displayed an order of Pinus armandii > Pinus massoniana >Larix kaempferi . Lichen community of ten tree species were clustered into three subgroups,all the introduced tree species were clustered into one subgroup.[Conclusion] We concluded that the secondary forests of Shnenongjia Mountain possessed a higher epiphytic lichen species richness,and epiphytic lichen diversity varied widely among tree species,so tree species diversity should be of special importance in maintaining diversity of epiphytic lichens in this area. Impacts of the introduced exotic tree species on lichen diversity of the secondary forests of Shennongjia Mountain,should be deeply studied in the future.
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