阿勒泰东部山区森林生态系统树生地衣群落特征的初步研究

根据多年的研究资料并采用聚类分析方法对分布在阿勒泰东部山区森林生态系统的树生地衣群落结构进行定量研究。结果表明,分布在该地区的树生地衣种类形成了4种群落,（1）冷杉粉衣Calicium abietinum Pets＋黑盘灰衣Tephromela atra（Hundson）;（2）土星猫耳衣Leptogium saturninum（Dicks．）＋脱落网衣Lecidea elabens Fr．;（3）槽梅衣Parmelia sulcata Tayl. apud Mack＋粉树花Ramalina farnacea（L．）Ach;（4）黄红橙衣Caloplaca flavorubescens＋黑蜈蚣衣Phaeophyscia nigricans（Flk．）群落。同时对地衣群落多样性、相似性和均匀度指数进行了系统地研究。     

新疆天山西部山脉森林生态系统地衣群落结构的初步研究

 根据多年的研究资料并采用聚类分析方法对分布在天山西部山脉的地衣群落结构进行了研究。结果表明,分布在该地区的地衣种类形成了6种群落:1) 土星猫耳衣（Leptogium saturninum)＋矮石蕊(Cladonia humilis)＋兰灰蜈蚣衣（Physcia caesia）群落;2）黑穗石蕊（Cladonia amaurocr     

乌鲁木齐南部山区森林生态系统树生地衣群落结构

为了探明乌鲁木齐南部山区树生地衣种类及其群落结构特征, 应用多元分析中的主成分分析及聚类分析方法, 对分布在乌鲁木齐南部山区森林生态系统中的树生地衣植物群落进行数量分类, 并对其群落结构的物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明, 分布在乌鲁木齐南部山区的树生地衣共有39种, 隶属于5目13科26属。根据多元分析结果, 将该地区的树生地衣划分为3种类型: (1) 小茶渍(Lecanora hageni (Ach.) Ach.) + 蜈蚣衣(Physcia stellaris (L.) Nyl.) + 柳茶渍(L. saligna (Schrad.) Zahlbr.)群落; (2) 斑面蜈蚣衣(Physcia aipolia (Humb.) Furm.) + 对开蜈蚣衣(Ph. dimidiata (Arn.) Nyl.) + 喇叭石蕊(Cladonia pyxidata (L.) Hoffm.)群落; (3) 拟石黄衣(Xanthoria fallax (Hepp) Arnold.) + 丽石黄衣(X. elegans (Link.) Th. Fr.)群落。群落3的多样性指数最大, 为1.509, 其次为群落2, 其多样性指数为1.109, 群落1的多样性指数最低, 为1.088。同时, 研究发现海拔高度和树种是影响乌鲁木齐南部山区森林生态系统树生地衣结构的两个重要因素。     

天山森林生态系统树生地衣植物群落数量分类及其物种多样性的研究

地衣是由低等植物中的藻类与菌类中的真菌和兰细菌共生而成的一群特殊的植物。由于耐寒耐旱对生活中的养分要求不高,在养纷贫瘠、环境恶劣的高山寒漠、平原、戈壁和沙漠中地衣都能生长,因而广泛地分布和生长在不同的生态环境中。有关新疆地衣方面的研究报道集中在物种分类水平上,对于地衣群落结构方面的研究比较少。因此,我们应用多元分析中的主分量分析及聚类分析方法对分布在天山森林生态系统中树生地衣植物群落进行数量分类并对群落结构物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明, 在西部天山不同森林生态系统中树生地衣群落的分布与海拔高度和树种有密切的关系, 不同海拔的不同类型的森林生态系统中分布着不同种类的树生地衣植物。 根据多元分析结果和生境的综合特征,该地区的树生地衣可划分为4种类型: 1) 茎口果粉衣+金黄茶衣群丛Chaenotheca stemonea+Candellaria aurella Association; 2)叉小孢衣+裸扁枝衣+粉唇蜈蚣衣群丛Bryoria furcellata+Evernia esorediosa+Physcia tribacoides Association; 3)亚广开梅衣+槽梅衣+疑小梅衣群丛Parmelia fertilis+Parmelia sulcata+Parmeliopsis ambigua Association; 4)睫毛黑蜈蚣衣+黑蜈蚣衣群丛Phaeophyscia ciliata+Phaeophyscia nigricans Association。其群落多样性指数以亚广开梅衣+槽梅衣+疑小梅衣群丛为最高 (1.920), 叉小孢衣+裸扁枝衣+粉唇蜈蚣衣群丛为最低 (1.562)。     

阿尔泰山两河源自然保护区地面生地衣群落物种分布特征

用聚类分析和主成分分析法对阿尔泰山两河源自然保护区地面生地衣群落进行划分;根据优势地衣种类进行群落命名。应用典范对应分析法探讨了地面生地衣种类分布与环境间的关系。结果表明:阿尔泰山两河源自然保护区地面生地衣可分为以下4个群落:白腹地卷+硫石蕊+喇叭粉石蕊群落;茸珊瑚枝+长根地卷+黑瘿地卷群落;土星猫耳衣+软鹿蕊+膜地卷群落;雪岛衣+北方石蕊+绿皮地卷群落。各群落中的地面生地衣种类与盖度,在一定程度上反映了地面生地衣在阿尔泰山两河源保护区分布格局与环境的关系。典范对应分析结果表明,阿尔泰山地面生地衣群落物种分布受到土壤湿度、土壤pH、海拔高度、林冠层郁闭度和灌木层盖度等环境因素的影响,其中海拔、土壤湿度、林冠层郁闭度等对地衣物种分布的影响最大。     

乌鲁木齐南部山区朽木生地衣群落特征的初步研究

应用聚类分析方法对分布在乌鲁木齐南部山区森林生态系统中朽木生地衣群落进行了数量分类并对群落结构、物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明,乌鲁木齐南部山区的朽木生地衣共计40种,隶属于6目12科和20属,朽木生地衣形成4种群落：（1）枪石蕊＋喇叭石蕊群落;（2）亚花松萝＋茸刺褐梅＋优果小网衣群落;（3）犬地卷＋分指地卷＋裂芽地卷群落;（4）柳茶渍＋土星猫耳衣＋粉石蕊群落。群落3和群落4的相似性比较高为0.768,次为群落2和群落3的相似性为0.647;群落2的多样性最大为1.957,群落4的多样性最小为1.365。同时发现在乌鲁木齐南部山区森林生态系统中朽木生地衣群落的分布与海拔高度和朽木的种类有密切的关系,不同海拔的不同类型的森林生态系统中分布着不同种类的朽木生地衣植物。     

乌鲁木齐达坂城山区地衣生态位特征的研究

为揭示达坂城山区地衣对生境资源的利用状况及竞争程度,该研究在野外设置30个样方并调查其物种盖度数据,利用生态位宽度、生态位重叠指数及排序分析,探讨达坂城山区地衣的生态位特征及环境影响因子。结果表明:(1)达坂城山区生态位最宽的为丽黄鳞衣(Rusavskia elegans)和内卷野粮衣(Circinaria contorta),对不同环境具有较强的适应性,其他地衣物种生态位宽度较窄,对环境资源利用程度低。(2)物种间生态位重叠值整体偏低,生态位重叠值较高的物种对极少,地衣物种生态位分化程度高,物种间竞争不激烈。(3)生态位较宽的物种与多数物种之间都存在生态位重叠,但重叠值较低; 一些生态位较窄的物种与其他物种之间的生态位重叠值较高; 生态位重叠和生态位宽度之间并无直接的线性关系。(4)地衣物种沿海拔梯度分布具有差异,海拔、光照强度、湿度、风速和人为干扰是本地区地衣群落物种生态位特征差异的主导环境因子。综上所述,达坂城山区地衣物种由于生境资源的竞争占据各自独特的生态位,形成了生态位的分化,群落较为稳定,沿海拔梯度的生境条件差异是物种差异分布的重要原因。该研究可为地衣群落构建研究提供理论依据,并对该地区地衣物种的多样性和生境保护具有重要意义。     

新疆博格达山地面生地衣群落数量分类及物种多样性

根据对新疆博格达山地面生地衣群落27个样点(20 m×20 m)调查的数据,以各地衣种的盖度为指标结合双向指示种分析方法(TWINSPAN)和除趋势对应分析法(DCA)对博格达山地面生地衣群落进行数量分类并分析了群落结构特征及其多样性和相似性。采用典范对应分析法(CCA)对各群落的物种分布格局与环境因子的关系进行了探讨。结果表明,TWINSPAN分析和DCA排序将分布在博格达山的37种地面生地衣分为以下5个群丛。群丛1:膜地卷(Peltigera membranacea)+伴藓大孢蜈蚣衣(Physconia muscigena)群丛;群丛2:地卷(Peltigera rufescens)+伴藓大孢蜈蚣衣(Physconia muscigena)群丛;群丛3:裂边地卷(Peltigera degenii)+平盘软地卷(Peltigera elisabethae)群丛;群丛4:喇叭石蕊(Cladonia pyxidata)+犬地卷(Peltigera canina)群丛;群丛5:盾鳞衣(Placidium squamulosum)+缠结茸枝衣(Seirophora contortuplicata)群丛。物种多样性以群丛4最大为3.427;群丛1最小为0.672;群丛1和群丛4间的相似性最高为0.889,群丛3和群丛4相似性系数最低为0.607。CCA排序结果反映,该地区地面生地衣的分布受到森林植被郁闭度、人为干扰、光照强度的影响,而地表植被盖度和土壤pH等因素的影响不大。     

新疆博格达山岩面生地衣群落结构特征

根据对新疆博格达山岩面生地衣群落20个样点(20m×20m)调查的数据,以各地衣种的盖度为指标结合双向指示种分析方法(TWINSPAN)和除趋势对应分析法(DCA)对博格达山岩面生地衣群落进行数量分类并分析了群落结构特征及其多样性和相似性。采用典范对应分析法(CCA)对各群落的物种分布格局与环境因子的关系进行研究。结果表明,TWINSPAN分析和DCA排序将分布在博格达山的37种岩面生地衣分为以下5个群丛。群丛1:斑纹网衣(Lecidea tessellate Florke)+粉芽盾衣(Peltula euploca(Ach.)Poelt)+杜瑞氏黄梅(Xanthoparmelia durietzii Hale)群丛,有25个种,总覆盖度为30.145%,多样性为4.025;群丛2:袋衣(Hypogymnia physodes(L.)Nyl.)+白边平茶渍(Aspicilia sublaqueata(H.Magn.)J.C.Wei)+砖孢胶衣(Collema subconveniens Nyl.)群丛,有17个种,地衣总盖度为15.885%,多样性为3.196;群丛3:聚茶渍(Lecanora accumulate H.Magn.)+丽石黄衣(Xanthoria elegans(Link)Th.Fr.)+亚洲平茶渍(Aspicilia asiatica(H.Magn.)Yoshim.)群丛,有30个种,地衣总盖度为37.87%,多样性为4.357;群丛4:中华石果衣(Endocarpon sinense H.Magn.)+伴藓大孢蜈蚣衣(Physconia muscigena(Ach.)Poelt.)+垫脐鳞衣(Rhizoplaca melanophthalma(DC.)LeuckertPoelt)群丛,有24个种,地衣总盖度为30.458%,多样性为3.912;群丛5:石胶衣(Collema flaccidum(Ach.)Ach.)+短绒皮果衣(Dermatocarpon vellereum Zschacke)+绿黑地图衣(Rhizocarpon viridiatrum(Wulfen)Korber.)群丛,有18个种,地衣总盖度为19.331%,多样性为3.515。CCA排序结果反映,该地区岩面生地衣的分布与海拔高度、光照强度、岩石pH和人为干扰有关,其中影响最大的因素是海拔高度,其次为光照强度和干扰。坡向和岩石大小对地衣种类分布的影响不显著。     

Algal and Fungal Diversity in Antarctic Lichens

The composition of lichen ecosystems except mycobiont and photobiont has not been evaluated intensively. In addition, recent studies to identify algal genotypes have raised questions about the specific relationship between mycobiont and photobiont. In the current study, we analyzed algal and fungal community structures in lichen species from King George Island, Antarctica, by pyrosequencing of eukaryotic large subunit (LSU) and algal internal transcribed spacer (ITS) domains of the nuclear rRNA gene. The sequencing results of LSU and ITS regions indicated that each lichen thallus contained diverse algal species. The major algal operational taxonomic unit (OTU) defined at a 99% similarity cutoff of LSU sequences accounted for 78.7–100% of the total algal community in each sample. In several cases, the major OTUs defined by LSU sequences were represented by two closely related OTUs defined by 98% sequence similarity of ITS domain. The results of LSU sequences indicated that lichen‐associated fungi belonged to the Arthoniomycetes, Eurotiomycetes, Lecanoromycetes, Leotiomycetes, and Sordariomycetes of the Ascomycota, and Tremellomycetes and Cystobasidiomycetes of the Basidiomycota. The composition of major photobiont species and lichen‐associated fungal community were mostly related to the mycobiont species. The contribution of growth forms or substrates on composition of photobiont and lichen‐associated fungi was not evident.     

乌鲁木齐南部山区岩面生地衣群落特征的研究

应用多元分析中的主分量分析及聚类分析方法对分布在乌鲁木齐南部山区森林生态系统中岩面生地衣群落进行数量分类并对群落结构物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明,乌鲁木齐南部山区的岩面生地衣共计49种,隶属于4目13科23属,岩面生地衣形成3种群落:(1)湿润石生地衣群落(Hygro-lichen community)定名为疣微孢衣Acarospora verruculosa+粉盘平茶渍A.alphaplaca+斑纹网衣Lecidea tessellata群落;(2)干燥石生地衣群落(Xero-lichen community)定名为多形茶渍Lecanora polytropa+破小网衣Lecideacarpathica群落;(3)高山石生地衣群落(Alpino-lichen community)定名为不等瓶口衣Verrucaria iaequalis+皮果衣Dermatocarpon miniatum群落。同时发现在乌鲁木齐南部山区森林生态系统中岩面生地衣群落的分布与海拔高度和基物的种类有密切的关系,不同海拔的不同类型的森林生态系统中分布着不同种类的岩面生地衣。     

Vertical distribution of epiphytic lichens on Quercus laurina Humb. & Bonpl. in a remnant of cloud forest in the state of Veracruz,México

In the tropics, corticolous lichen richness and cover tend to increase from the trunk base to the top of the crown of trees. In this study we calculated the total beta diversity of the lichen community along a vertical gradient on Quercus laurina in Mexican cloud forest. By comparing the richness and cover of the lichens by zone, we show that foliose and fruticose lichens are a minor component of the total lichen species richness, but have a higher cover than the crustose lichens. Five zones were identified along each phorophyte (n = 15) with a diameter at breast height >40 cm. A total of 92 species were identified. Of these, 38% were found only in a single zone, 51% were shared between the different zones and 11% occurred across all zones. Species richness and cover increased from the lowest to the highest zones of the phorophytes. Dissimilarity in species composition between the zones could be explained by species replacement. An indicator species analysis revealed that only a few species, e.g. Hypotrachyna vexans, H. cf. sublaevigata and Ramalina cf. sinaloensis prefer a particular zone. The results show that the lichen community associated with Quercus laurina phorophytes is highly diverse and suggest that species richness and cover are related to the zone and the various growth forms.     

Bole epiphytic lichens as potential indicators of environmental change in subtropical forest ecosystems in southwest China

Lichen epiphytes are applied as excellent environmental indicators worldwide. However, very little is known about epiphytic lichen communities and their response to forest dynamics in subtropical China. This paper proposes the applications of the cover, diversity, and functional traits of epiphytic lichens to assess environmental changes associated with succession in subtropical forests of southwest China. Bole lichens were sampled from 120 plots of eight representative forest types in the Ailao Mountains. Total cover, species richness, diversity and community structure of bole lichens differed significantly among forest types, and the highest cover and diversity occurred in the Populus bonatii secondary forest (PBSF). Sixty-one indicator species were associated with particular forest types and more than 50% occurred in the PBSF. Both cover and diversity of most lichen functional groups varied regularly during forest succession. Lichen pioneer species were not displaced by competitively superior species as succession proceeds and cyanolichens were more prevalent in secondary forests. The results also highlight the importance of habitat variables such as canopy openness, host diversity, forest age, tree size, the size of the largest tree, tree density, and basal area on the lichen community. Consequently, our findings support the notion that epiphytic lichens, in terms of cover, diversity, species composition and functional traits can be used as effective indicators for large-scale and long-term forest monitoring. More importantly, the narrowly lobed foliose group was the best candidate indicator of environmental conditions in this region. The combined application of lichen indicator species and functional groups seemed to be a more reliable and more powerful method for monitoring forest dynamics in subtropical montane ecosystems.     

Environmental context shapes the bacterial community structure associated to Peltigera cyanolichens growing in Tierra del Fuego,Chile

The structure of the associated bacterial community of bipartite cyanolichens of the genus Peltigera from three different environmental contexts in the Karukinka Natural Park, Tierra del Fuego, Chile, was assessed. The sampling sites represent different habitat contexts: mature native forest, young native forest and grassland. Recently it has been determined that the bacterial community associated to lichens could be highly structured according to the mycobiont or photobiont identities, to the environmental context and/or to the geographic scale. However, there are some inconsistencies in defining which of these factors would be the most significant on determining the structure of the microbial communities associated with lichens, mainly because most studies compare the bacterial communities between different lichen species and/or with different photobiont types (algae vs. cyanobacteria). In this work bipartite lichens belonging to the same genus (Peltigera) symbiotically associated with cyanobacteria (Nostoc) were analyzed by TRFLP to determine the structure of the bacterial community intimately associated with the lichen thalli and the one present in the substrate where they grow. The results indicate that the bacterial community intimately associated differs from the one of the substrate, being the former more influenced by the environmental context where the lichen grows.     

Lichen diversity and composition in Araucaria forests and tree monocultures in southern Brazil

Tree plantations for commercial use have been replacing native ecosystems all over the world. We investigated how forest conversion to plantations of exotic and native tree species may influence lichen diversity and composition in a southern Brazilian landscape. The lichen community from the National Forest of São Francisco de Paula was studied using three stands of each of the four vegetation types: native Araucaria forest and plantations of Araucaria, Pine and Eucalyptus trees. All plantation stands were surrounded by native Araucaria forest, were of smaller size and were allowed to endure longer than commercially managed plantations. Lichen species and their cover abundance were recorded on tree trunks from 30 to 150 cm above soil level in ten host-trees that were randomly selected in each replication. Seventy-eight lichen species, from 18 genera and 9 families, were registered. Conversion of native forest to plantations of exotic tree species altered species composition by reducing the occurrence of shade tolerant lichens. Plantations of Araucaria angustifolia sustained the highest lichen diversity measured, because this is an excellent host species. These results suggest that a greater diversity of lichens can be preserved in the landscape, if plantations of the exotic Pinus and Eucalyptus genera are replaced by plantations of this native species.     

乌鲁木齐南部山区森林生态系统树生地衣群落结构

为了探明乌鲁木齐南部山区树生地衣种类及其群落结构特征,应用多元分析中的主成分分析及聚类分析方法,对分布在乌鲁木齐南部山区森林生态系统中的树生地衣植物群落进行数量分类,并对其群落结构的物种多样性、相似性和均匀度等群落参数进行了比较系统的研究。结果表明,分布在乌鲁木齐南部山区的树生地衣共有39种,隶属于5目13科26属。根据多元分析结果,将该地区的树生地衣划分为3种类型：（1）小茶渍（Lecanorahageni（Ach．）Ach．）＋蜈蚣衣（肋归ciastellaris（L．）Nyl．）＋柳茶渍（￡-。saligna（Schrad．）Zahlbr．）群落;（2）斑面蜈蚣衣（Physciaaipolia（Humb．）Furm．）＋对开蜈蚣衣（Ph．dimidiata（Arn．）Nyl．）＋喇叭石蕊（Cladoniapyxidata（L．）Hoffm．）群落：（3）拟石黄衣（Xanthoria fallax（Hepp）Arnold．）＋丽石黄衣（xelegans（Link．）Th．Fr．）群落。群落3的多样性指数最大,为1．509,其次为群落2,其多样性指数为1．109,群落1的多样性指数最低,为1．088。同时,研究发现海拔高度和树种是影响乌鲁木齐南部山区森林生态系统树生地衣结构的两个重要因素。     

Functional diversity and traits assembly patterns of lichens as indicators of successional stages in a tropical rainforest

Understanding community assembly patterns with regard to functional traits, which may be common to different species, allows us to compare ecological communities in a wider range of environmental and phytogeographic conditions. Moreover, a functional approach may facilitate the comprehension of the relation between biotic changes and ecosystem functions in complex systems such as tropical forests. Considering the lack of information in relation to the influence of environmental conditions on lichen functional traits, on lichen functional patterns in tropical forests and the potential usage of this approach in bioindication studies, this paper aims at (i) determining the functional structure of the lichen communities along the forest succession gradient, (ii) assessing the relation of lichen functional traits to this gradient and (iii) verifying the potential of using lichen functional traits as indicators of successional stages in tropical rainforests. Lichens were sampled in 24 sampling units of three successional stages (6–10; 12–20; and 40–60 years of recovering). The results corroborated our main hypothesis that the functional structure of the lichen communities responds to structural changes along a forest regeneration gradient. Growth forms (foliose, fruticose and crustose) as well as some reproductive trait states (lirella, isidia and perithecia) were the most suitable lichen traits to be used as indicators of forest succession in the southern edge of the Atlantic Rainforest. Lirella, fruticose and foliose were more related to earlier successional stages; isidia was more related to intermediate stages, while perithecia and crustose were more related to older stages. These results reinforce the ability of lichens to be used as bioindicators of forest conditions.     

基于功能性状及系统发育的乌鲁木齐达坂城山区地衣群落构建机制

选取达坂城山区地衣群落为研究对象,在野外设置了30个样方,调查样方内地衣物种。利用分子标记构建系统发育树,检验功能性状的系统发育信号,计算地衣群落净谱系亲缘关系指数(net relatedness index,NRI)和最近种间亲缘关系指数(nearest taxon index,NTI),探讨地衣群落构建机制,结合典范对应分析(CCA)等方法探讨达坂城山区地衣群落构建的主要环境驱动因子。结果表明：达坂城山区调查发现地衣共有111种,隶属14目、25科、48属。生长形式、光生物类型、繁殖方式、繁殖结构和基物类型5种功能性状均具有显著的系统发育信号(P<0.05),具有谱系保守性。不同海拔梯度群落系统发育结构不同,在低海拔区域,环境干旱,具有干扰,谱系随机至弱发散结构,环境过滤和相似性限制共同作用于群落;在中海拔区域,湿度适中,风速低,人为干扰较弱,地衣群落的谱系结构聚集,环境过滤在群落中起主导作用;而在高海拔区域,环境湿度高,风速强,无人为干扰,群落谱系发散,相似性限制在群落中起主导作用。其中,海拔和物种丰富度呈显著正相关,风速和湿度对系统发育指数有显著影响,海拔、湿度、风速和人为干扰对部分功能性状有显著影响。海拔、湿度和风速作为主要的环境筛影响研究区地衣群落构建过程。     

Corticolous lichens as potential bioindicators of fire history: a study in the cerrado of the Distrito Federal, central Brazil

Abstract. The aim of this study was to investigate the potential use of epiphytic corticolous lichens as indicators of fire history in the cerrado (savannas) of central Brazil. Work was carried out at the Reserva Ecológica do IBGE and the Jardim Botânico de Brasilia, 33 km outside Brasilia D.F., in ten plots of cerrado denso within the ‘Fire Project’ area. Each plot was subjected to a specific prescribed burning regime, with study sites varying from a plot protected from fire for over 20 years to a plot burned every 2 years. Research was carried out in two stages: (1) a preliminary survey of plots with different fire histories, measuring variables about the lichen habitat and the lichen communities present in the habitats; (2) lichen sampling in plots with different fire histories, where collection and identification of lichen species took place. Field techniques used included plotless sampling, and identification of lichens was carried out using taxonomic keys, both in the field and in the laboratory. The results show that fire is a major determinant of epiphytic corticolous lichen communities in cerrado denso vegetation. The abundance, distribution and recolonization of lichen communities can clearly be correlated with the frequency and behaviour, in terms of homogeneity and flame heights, of the fires that have occurred in each of the plots surveyed. Particular lichen species also show differential sensitivities to fire frequency and behaviour. This study shows that responses of corticolous lichens, at both the community and species level, can be used as bioindicators of fire history in areas of cerrado denso vegetation in central Brazil.     

Contrasting functional traits maintain lichen epiphyte diversity in response to climate and autogenic succession

Aim Lichen epiphytes are important for biodiversity conservation and are also widely applied as environmental indicators. However, biogeographical and ecological knowledge underpinning lichen epiphyte conservation, and the use of lichens as indicators, is based primarily on a limited range of ‘macrolichen’ species. Wider trends in epiphyte biodiversity remain largely unexplored. This paper examines the community structure of lichen epiphytes on aspen (Populus tremula L.) in Scotland, including species across all functional groups and comprising, therefore, taxonomically difficult ‘microlichens’. Location Northern Britain (Scotland). Methods Epiphytes were sampled from 12 sites throughout Scotland and examined at two scales: between and within aspen stands. Species were classified into contrasting functional groups and ordination by detrended correspondence analysis was used to summarize community structure. Results Within aspen stands (between trees) epiphyte communities showed successional patterns related to tree age. These successional patterns changed predictably for stands aligned along a climatic gradient (between stands). Main conclusions A dual climatic–successional trend in epiphyte community structure is presented. Large‐scale trends in epiphyte diversity are explained as the local response of species with contrasting functional traits to climate and autogenic succession. Turnover of functional groups between stands is positively related to β‐diversity, and ecological limits to the frequency of contrasting functional groups are presented. Accordingly, the study and application of lichen species with similar functional traits may inadequately represent patterns of biodiversity. This prompts criticism of the currently accepted conservation strategy, i.e. (1) an emphasis in the conservation literature on ‘macrolichen’ species with similar ecologies and (2) the application of lichen indices over climatically variable geographical areas.