Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Forest fragmentation and habitat destruction are threatening many species worldwide. In addition to habitat loss, fragmentation decreases the number of species, changing the composition of communities, resulting in microclimatic changes, and also changes the tree mortality rates and increases the number of forest edges. The creation of edges causes a rapid response from the primary ecosystem, which is known as edge effect. Edge effects are many physical and biological phenomena associated with abrupt artificial limits of fragmented habitat. Understanding the responses of communities to environmental changes can be quite complex in species rich communities. Thus, some of these estimates can be based on common functional traits among different species. Lichens are especially sensitive to human impact on forest ecosystems, so it can be used as habitat quality indicators. Thus, this study aims to evaluate how the richness and composition of liquênicas species as well as their functional attributes, respond to anthropogenic edge and resulting forest within the forest fragmentation in a Atlantic Forest reminant. The study was conducted at the Refúgio de Vida Silvestre Mata do Junco (RVSMJ), in Capela, Sergipe. 617 samples were collectes, which were distributed among the areas of anthropogenic and inside edge. The identification work resulted in the identification of 102 species belonging to 40 genera and 14 families. There was a high similarity in species between anthropogenic and inside edge, showing that little has been the change in composition in the study sites. The results for species richness between edge and interior of the fragment showed a greater amount of corticicolous crostosos moss in the forest. The DAP and pH factors were directly related to the increase of species richness in the forest. It was shown that functional attributes lichen vary in anthropogenic edge and interior of forest fragments, and that these can be used as biomarkers of edge effect, since, lichens, as well as their functional features, are quite sensitive to changes environmental as those that occur in forest edges. Thus, our results showed some important trends for the understanding of edge effects on lichens, demonstrating the importance of including them in conservation strategies and contributing to their use in monitoring as indicator species of environmental change. / A fragmentação florestal e a destruição do habitat estão ameaçando muitas espécies em todo o mundo. Além da perda de habitat, a fragmentação diminui o número de espécies, alterando a composição de comunidades, causa mudanças microclimáticas, altera as taxas de mortalidade de árvores e aumenta o número de bordas florestais. A criação de bordas gera uma resposta primária rápida do ecossistema, a qual é conhecida como efeito de borda. Os efeitos de borda são diversos fenômenos físicos e biológicos associados a abruptos limites artificiais de habitat fragmentado. Entender as respostas das comunidades às modificações do ambiente pode ser bastante complexo em comunidades ricas em espécies. Assim, algumas dessas estimativas podem ser baseadas em características funcionais comuns entre diferentes espécies. Liquens são especialmente sensíveis ao impacto humano nos ecossistemas florestais. Por isso, podem ser usados como indicadores de qualidade do habitat. Desta forma, este trabalho tem como objetivo avaliar como a riqueza e composição de espécies liquênicas, assim como seus atributos funcionais, respondem à borda antrópica e interior florestal resultante da fragmentação florestal em remanescente de Mata Atlântica. O estudo foi realizado no Refúgio de Vida Silvestre Mata do Junco (RVSMJ), localizado no município de Capela, no estado de Sergipe. Foram coletadas 617 amostras de liquens corticícolas crostosos distribuídas entre as áreas de borda antrópica e interior. O trabalho de identificação permitiu o reconhecimento de 102 espécies, distribuídas em 40 gêneros e 14 famílias. Houve alta similaridade nas espécies entre borda antrópica e interior, mostrando que pouca foi a variação da composição nos ambientes estudados. Os resultados para riqueza entre borda e interior do fragmento mostraram uma maior quantidade de liquens no interior da floresta. Os fatores DAP e pH estiveram diretamente relacionados ao aumento de riqueza no interior da floresta. Foi demonstrado que atributos funcionais de liquens variam em relação à borda antrópica e interior de fragmentos florestais, e que estes podem ser utilizados como bioindicadores de efeito de borda, uma vez que, os liquens, assim como seus traços funcionais, são bastante sensíveis às alterações ambientais como as que acontecem em bordas florestais. Desta forma, nossos resultados mostraram algumas tendências importantes para a compreensão dos efeitos de borda sobre os liquens, demonstrando a importância de incluí-los em estratégias de conservação e contribuindo para o seu uso em monitoramento como espécies indicadoras de modificações ambientais.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The interruption of the blood supply causes a change in the cellular redox status, promotes oxidative stress, tissue damage and changes in heart function. Therefore, antioxidant compounds, such as usnic acid, can prevent these changes, since they are able to re-establish cellular redox status and preserve the tissue functions. The goal of this study was to determine whether pretreatment with inclusion complex usnic acid (UA) / β-cyclodextrin (βCD) promotes cardioprotection after ischemia and reperfusion. Initially, the characterization of inclusion complex between the AU and the βCD was performed through thermogravimetry / derivative thermogravimetry (TG / DTG), differential scanning calorimetry (DSC), spectrophotometry in the infrared (FTIR) and scanning electron microscopy (MEV). After characterization, was initiated evaluating the cardioprotective effects of the inclusion complex AU / βCD. For this, Wistar rats (250-300 g) divided into two groups: the group pretreated with 50 mg / kg / day AU / βCD and pretreated with βCD group. After the pretreatment, the heart of the animal was removed to be mounted in an isolated organ perfusion system for induction of ischemia and reperfusion and were evaluated the pressure developed in the left ventricle (LVDP), heart rate (HR) and arrhythmia severity index (ASI). Also was determined in liver and heart the amount of lactate dehydrogenase (LDH) released, the formation of malondialdehyde (MDA), the activity of superoxide dismutase (SOD) and catalase (CAT). Furthermore was verified the amount of thiol groups. The results of the physico-chemical characterization showed that UA was complexed in the cavity of βCD and may be seen in the TG weight loss in the second step, where the inclusion complex showed Δm = 19.2% while the physical mixture, Δm = 16.2%. Furthermore, it was demonstrated by SEM that the physical mixture has not interacted with βCD while the inclusion complex underwent shape change. The FTIR spectra indicated the presence of the AU in the inclusion complex in a higher proportion, in turn, the physical mixture was observed in the presence of AU lesser extent. When evaluating the cardioprotective effects of the inclusion complex AU / βCD, it was found that the pretreatment preserved LVDP (AU: 89.9% vs. 6.3 + βCD: 53.9 + 8.6%, p < 0 05) reduced the scores obtained in ASI (AU: 2.5 + 0.5 ua vs. βCD: 11.00 + 0.57 ua; p < 0.0001) and did not change the FC (AU / βCD: 78 5 + 8.6% vs βCD: 79.6 + 9.2%, p > 0.05). In biochemical assays, pretreatment reduced the amount of LDH released (AU: 0.063 + 0.026 U / L vs βCD: 0.224 + 0.036 U / L, p < 0.05) reduced the formation of MDA (AU: 5, 87 + 0.57 nmol MDA / g vs βCD: 13.02 + 1.04 nmol MDA / g, p < 0.0001), promoted the SOD activity (AU: 0.086 + 0.013 U SOD / mg protein vs. βCD: 0,050 + 0,004 U SOD / mg protein, p < 0.05) and CAT (AU: 0.054 + 0.006 ΔE / min / mg protein vs. βCD: 0.023 + 0.002 ΔE / min / mg protein; p < 0.001) and increased presence of thiol groups (AU: 97.83 + 4.23 mol / mg protein vs. βCD: 54.31 + 3.28 mol / mg protein, p < 0.0001 ). Moreover, to investigate the toxicity was not observed change in baseline levels of LDH (AU: 0.068 + 0.021 U / L vs βCD: 0.070 + 0,023U / L; p > 0.05) and MDA (AU: 8.59 + 0.27 nmol MDA / g vs βCD: 8.43 + 0.21 nmol MDA / g, p > 0.05) nor change in the SOD activity (AU: 0,025 + 0,001 U SOD / mg protein vs. βCD 0.026 + 0.001 U SOD / mg protein, p > 0.05), or CAT (AU: 0.020 + 0.004 ΔE / min / mg protein vs. βCD: 0.015 + 0.002 ΔE / min / mg protein, p > 0.05) in the liver by promoting increase of thiol groups only (AU: 245.4 + 15.6 mmol / mg protein vs. βCD: 181.8 + 14.3 mmol / mg protein , p < 0.05). Thus, it was found that the pretreatment with the inclusion complex preserved contractile function, heart protection promoted and showed no signs of toxicity. / A interrupção do suprimento sanguíneo causa alteração do status redox celular, promove estresse oxidativo, danos teciduais e alteração da função cardíaca. Diante disso, compostos antioxidantes, como o ácido úsnico, podem prevenir essas alterações, uma vez que são capazes de reestabelecer o status redox celular e de preservar as funções teciduais. Assim, o objetivo desse estudo foi verificar se o pré-tratamento com complexo de inclusão ácido úsnico (AU)/β-ciclodextrina (βCD) promove a cardioproteção após a lesão por isquemia e reperfusão. Inicialmente, foi realizada a caracterização do complexo de inclusão entre o AU e a βCD através das técnicas de termogravimetria/termogravimetria derivada (TG/DTG), calorimetria exploratória diferencial (DSC), espectrofotometria na região do infravermelho (FTIR) e microscopia eletrônica de varredura (MEV). Após a caracterização e confirmação da formação de complexo de inclusão entre o AU e a βCD, foi iniciado a avaliação dos efeitos cardioprotetores do complexo de inclusão AU/βCD. Para tanto, foram utilizados ratos wistar (250-300 g) distribuídos em dois grupos: o grupo pré-tratado com 50 mg/kg/dia de AU/βCD e o grupo pré-tratado com βCD. Após o pré-tratamento, o coração dos animais foi removido para ser montado em sistema de perfusão de órgão isolado para a indução da lesão por isquemia e reperfusão, onde foram avaliados a pressão desenvolvida no ventrículo esquerdo (PDVE), frequência cardíaca (FC) e o índice de severidade de arritmia (ASI). Em seguida, foi determinado em fígado e coração a quantidade de lactato desidrogenase (LDH) liberada, a formação de malondialdeído (MDA), a atividade das enzimas Superóxido Dismutase (SOD) e Catalase (CAT) e verificado a quantidade de grupamentos tióis. Os resultados da caracterização físico-química demonstraram que o AU foi complexado a cavidade da βCD, podendo ser visto na TG na segunda etapa de perda de massa, onde o complexo de inclusão apresentou Δm=19,2% enquanto a mistura física, Δm=16,2%. Além disso, foi demonstrado pela MEV que a mistura física não interagiu com a βCD ao passo que o complexo de inclusão sofreu alteração de forma. Os espectros de FTIR indicaram a presença do AU no complexo de inclusão em maior proporção, por sua vez, na mistura física foi observada a presença do AU em menor proporção. Ao avaliar os efeitos cardioprotetores do complexo de inclusão AU/βCD, verificou-se que o prétratamento preservou a PDVE (AU: 89,9 + 6,3% vs βCD: 53,9 + 8,6%; p < 0,05), reduziu os escores obtidos no ASI (AU: 2,5 + 0,5 u.a. vs βCD: 11,00 + 0,57 u.a.; p < 0,0001) e não alterou a FC (AU/βCD: 78,5 + 8,6% vs βCD: 79,6 + 9,2%, p > 0,05). Nos ensaios bioquímicos, o pré-tratamento reduziu a quantidade de LDH liberada (AU: 0,063 + 0,026 U/L vs βCD: 0,224 + 0,036 U/L; p < 0,05), diminuiu a formação de MDA (AU: 5,87 + 0,57 nmol de MDA/g de tecido vs βCD: 13,02 + 1,04 nmol de MDA/g de tecido, p < 0,0001), promoveu a atividade da SOD (AU: 0,086 + 0,013 U SOD/mg de proteína vs βCD: 0,050 + 0,004 U SOD/mg de proteína; p < 0,05) e da CAT (AU: 0,054 + 0,006 ΔE/min/mg de proteína vs βCD: 0,023 + 0,002 ΔE/min/mg de proteína; p < 0,001) e aumentou a presença de grupos tióis (AU: 97,83 + 4,23 μmol/mg de proteína vs βCD: 54,31 + 3,28 μmol/mg de proteína; p < 0,0001). Ademais, ao investigar a toxicidade, não foi evidenciada alteração dos níveis basais de LDH (AU: 0,068 + 0,021 U/L vs βCD:0,070 + 0,023U/L; p > 0,05) e de MDA (AU: 8,59 + 0,27 nmol de MDA/g de tecido vs βCD: 8,43 + 0,21 nmol de MDA/g de tecido, p > 0,05) , nem alteração da atividade da SOD (AU: 0,025 + 0,001 U SOD/ mg de proteína vs βCD: 0,026 + 0,001 U SOD/mg de proteína, p > 0,05) e nem da CAT (AU: 0,020 + 0,004 ΔE/min/mg de proteína vs βCD: 0,015 + 0,002 ΔE/min/mg de proteína; p > 0,05) no tecido hepático, promovendo apenas aumento de grupamentos tióis (AU: 245,4 + 15,6 μmol/mg de proteína vs βCD: 181,8 + 14,3 μmol/mg de proteína, p < 0,05). Assim, verificou-se que o pré-tratamento com o complexo de inclusão preservou a função contrátil, promoveu cardioproteção e não mostrou sinais de toxicidade.

The crustose genus Staurothele (Verrucariaceae, Ascomycota) is a common component of the lichen flora from subneutral to alkaline silicate rocks in temperate to cold-temperate climates. Our field study in the karst system of northern Vietnam showed that it is also common on dry to humid limestone in the wet tropics. Molecular data revealed that species of Staurothele from Vietnam belong to an unnamed clade sister to the genus Endocarpon, together with the tropical Australian species Staurothele pallidopora and Staurothele diffractella, a North American species recently transferred to Endocarpon based on molecular data. The genus Willeya is here resurrected for this clade of crustose epilithic Staurothele with pale ascospores. Eight new combinations are proposed and three new species of Willeya are described from Vietnam. Sampling tropical members of a lichen family previously mostly known from temperate areas contributed significantly to improving its generic classification.

7 SUMMARY This thesis is divided into two separate portions. The first part covers my own lichen floristic exploration of the Károvské údolí locality stretching out along the southern limits of Prague near Zbraslav. The location is formed by relatively steep slopes with orientation to North and South. Natural conditions are characterised by communities of xerothermic steppes and oak groves with alder clumps and hornbeams prevailing in lower parts along the Károvský potok stream. Geologically, the parent rock consists of shale rocks of acid chemical composition. Duting my search, I recorded 116 lichen species. Among them, saxicolous and terricolous lichens characteristic of acid rock outcrops and xerotherm steppes prevail. During exploration, I found also the critically endangered (CR) species Peltigera elisabethae, endangered species (EN) Flavoparmelia caperata and representatives of the genus Verrucaria, tolerant of long-term freshwater flooding - V. cf. andesiatica, V. aquatilis and V. funckii. One of species discovered, Pertusaria flavicans, has not been recorded in the Czech Republic todate. This locality is home to a summer house resort which has expanded the list of lichens by basophilic species which inhabit anthropogenic substrata. My master thesis is the first thorough research of the lichen flora...

Epiphytic lichens are under considerable grazing pressure due to invertebrate lichenivores, mostly gastropods. Preferences of tree-climbing gastropods affect vertical distribution of lichens, their habitat preferences and whole area of distribution. Higher grazing pressure is expected on sites with basic subsoil and sufficient sources of calcium, where the abundance of gastropods is higher. Most of researches about the topic of grazing pressure were therefore conducted on such sites, although this hypothesis has never been formally tested. Epiphytic communities are also affected by pH and other properties specific to its photophyte. Nevertheless, it is not known, if the same applies for grazing gastropods and how is the grazing pressure affected by tree species. I have addressed these questions in my thesis. I set an 80-days-long field transplantation experiment in the mixed forest of Moravský kras (South Moravia, Czech Republic). Glass fiber meshes with lichen thalli were placed on sixty trunks of three tree species (Carpinus betulus - hornbeam, Abies alba - fir, Fagus sylvatica - common beech) on both calcareous (limestone) and acidic (granodiorite) sites. Abundance and diversity of gastropods were measured. Determined grazing pressure was higher than pressure detected by other authors and was...

This thesis is the culmination of a graduate research project involving a floristic survey of the lichens of the Spring Mountain National Recreation Area (SMNRA), Humboldt-Toiyabe National Forest, Nevada. The project was based on extensive collections made between 1997 and 2007 as part of an air pollution biomonitoring program and a baseline established by Larry St. Clair (BYU). The Spring Mountains are a sky island mountain range in the Mojave Desert located less than an hour northwest of Las Vegas. A floristic survey of the lichen communities in the Spring Mountains represents a major addition to our understanding of the lichen flora of the Mojave Desert, a poorly studied region in western North America. This thesis also compares the lichen flora of the SMNRA with other lichen floras of the Mojave Desert based on a literature survey of all the lichen studies conducted in the Mojave Desert. The SMNRA species list represents 58% of the 217 species in 68 genera reported for the Mojave Desert. This survey of all reported Mojave lichen species reveals several interesting interactions related to species diversity, substrate, and growth form distribution patterns. These interactions appear to be influenced by two general factors: Microhabitat conditions and available substrates – which are further defined by differences in geological substrates, occurrence and development of woody plant communities, and a combination of environmental factors – elevation, temperature, precipitation, and insolation. Drier and warmer habitats are generally dominated by crustose species with some, mostly smaller, foliose taxa in protected microhabitats usually with shaded or northern exposures. Fruticose species are generally lacking or sparse with smaller thalli when found in hot and dry habitats. All the fruticose species reported from the Mojave Desert sites were rare and had very small thalli. Many foliose and fruticose species, with larger, more complex thalli and thus greater surface area, are more susceptible to higher rates of water loss and therefore occur less frequently in extreme arid locations. The lichen communities in the Mojave Desert respond to sharp contrasts in microhabitat conditions with exposed, lower elevation sites having lower numbers of species along with more drought resistant growth forms – crustose and squamulose species. The Spring Mountains NRA, with high elevation mountains and well developed woody plant communities, accommodates a large variety of microhabitat conditions spread over a complex temperature and moisture gradient. These conditions have resulted in the highest species diversity (124 species in 48 genera) and the greatest number of foliose and corticolous species when compared with all of the other Mojave Desert lichen floras.

Tableau d'honneur de la Faculté des études supérieures et postdoctorales / Dans la Réserve de Parc National du Canada de l'Archipel-de-Mingan (RPNCAM), Québec, un important verdissement des landes à lichens est observé depuis 1967 et serait surtout lié à l’établissement d'espèces arbustives telles que la camarine noire (Empetrum nigrum L.) et le bouleau nain (Betula pumila L.). L’analyse de photos aériennes de l’archipel (1967, 1988 et 2009) suggère que le recul des landes à lichens serait hétérogène à l’échelle locale, certaines landes à lichens montrant un recul rapide et d'autres se maintenant dans le temps. L’objectif de notre étude était de déterminer quels sont les paramètres locaux (sols, exposition, etc.) favorisant le recul des landes à lichens à la RPNAM. Pour suivre l'évolution du recul, des cartes du couvert lichénique de sept îles de la RPNCAM ont été produites par classification supervisée par pixel à partir de photos aériennes. Les résultats démontrent un recul des landes à lichens de 71% entre 1967 et 2009, bien que majoritairement observé entre 1967 et 1988 (50%). À partir de modèles écologiques construits avec des caractéristiques locales, nous avons pu déterminer que l’épaisseur de la couche de sol organique est une variable d’importance pour expliquer le recul survenu (AICcWt = 0.44). Cependant, les facteurs locaux favorisant le recul ainsi que les patrons de colonisation par les plantes vasculaires diffèrent selon la période considérée (1967-1988 et 1988-2009). En effet, l’épaisseur de sol organique semble importante pour expliquer le recul observé durant la première période seulement, durant laquelle de grandes étendues de landes à lichens ont été colonisées par un front d’avancée d’espèces vasculaires. Cette étude nous permet donc d’enrichir notre compréhension des changements de communautés végétales en milieu nordique. / In the Mingan Archipelago National Park Reserve (MANPR) of Québec, Canada, an important greening has been observed at the expense of terricolous lichens since 1967. This phenomenon occurring in lichen heaths is most likely linked to the encroachment of shrubs like the black crowberry (Empetrum nigrum L.) and the dwarf birch (Betula pumila L.). Aerial photos of the Mingan archipelago acquired in 1967, 1988 and 2009 reveal a retreat that appears heterogeneous at a local scale, with some lichen heaths decreasing rapidly in extent and others appearing stable over time. Our aim was to determine which local-scale characteristics (substrate, aspect, etc.) promote the retreat of the lichen heaths on the islands. Using supervised classification on the aerial photos, vegetation maps of seven islands of the MANPR have been generated to track the plant communities’ changes and quantify the retreat in lichen cover. Maps results show an average decrease of 71% between 1967 and 2009, with the majority of the retreat observed between 1967 and 1988 (50%). Models built with local characteristics suggest that the soil organic layer (SOL) thickness is important to explain the retreat (AICcWt = 0.44). However, explanative factors and vascular plant colonization patterns differ depending on the time interval studied (1967-1988 and 1988-2009). In fact, SOL thickness seems only important to explain the lichen heath retreat observed during the first time period, during which extensive lichen heaths areas were colonized by an advancing front of vascular plants. This study extends our comprehension of northern ecosystems dynamics.

La présence des bancs d'emprunts, utilisés comme sablières et gravières lors de la construction de routes dans la forêt boréale, est problématique. Les facteurs influençant la colonisation naturelle des plantes dans ces milieux ont d'abord été étudiés. Les résultats indiquent que la physicochimie et l'humidité du sol ont la plus grande influence. De plus, les bryophytes et les lichens sont les principaux colonisateurs primaires des bancs d'emprunt. Nous avons donc émis l'hypothèse que l'introduction de ces plantes invasculaires pourrait accélérer la végétalisation des bancs d'emprunt. Trois expériences de restauration à l'aide de bryophytes et de lichens ont été mises en place. Les résultats de ces expériences montrent que l'établissement des bryophytes et des lichens à partir de fragments est possible en une saison de croissance. L'ajout d'un paillis de paille a eu un effet négatif sur leur établissement.

Les peuplements lichéniques sont très sensibles aux perturbations et au développement d’un couvert végétal vasculaire, étant incapables de rivaliser pour l’accès à la lumière et aux nutriments du sol. Cette étude s’intéresse à l’évolution de la lande à lichens de l’île Nue dans la Réserve de Parc National du Canada de l’Archipel-de-Mingan, soit dans un contexte insulaire méridional et en présence de perturbations par les goélands argentés. L’analyse de photographies aériennes a permis de mesurer un recul de 85,5 % de la superficie occupée par le lichen de 1967 à 2009. Les espèces responsables de ce recul sont principalement des arbustes (~63 %, Rhododendron groenlandicum et Empetrum nigrum) et des herbacées (~35 %, Rubus idaeus et Chamerion angustifolium). Ce recul de la lande à lichens ne semble pas associé aux récents changements climatiques puisqu'il était plus important entre 1967-1988 qu'entre 1988-2009, soit avant qu’un léger réchauffement soit observé dans la région. De plus, le faible couvert lichénique mesuré autour des sites perturbés par les goélands indique que les perturbations sont probablement survenues après le remplacement du lichen par des espèces vasculaires, ce qui suggère que ces perturbations ne sont pas responsables du recul observé. Les perturbations par les goélands semblent toutefois favoriser le développement d’un couvert herbacé. Outre la perte au niveau des espèces lichéniques, aucun effet négatif du développement d'un couvert végétal vasculaire sur la diversité, la richesse spécifique et l’abondance des groupes fonctionnels n'a été observé. Nos résultats ne permettent donc pas de déterminer la cause du recul de la lande à lichens. Un changement des conditions édaphiques, suite à l’accumulation de matière organique depuis l’émergence des îles, et la dégradation progressive du pergélisol pourraient être responsable du changement de végétation observé, bien que des études soient nécessaires pour vérifier ces hypothèses. / Because they are unable to compete for light and soil nutrients, lichens are sensitive to disturbance and to the development of a vascular plant cover. As such, the objective of this study was to better understand changes in the dynamics of lichen barrens found on île Nue in the Mingan Archipelago National Park Reserve of Canada, where recent increase in vascular plant cover was observed. Specifically, we aimed to evaluate the role of recent climate warming and herring gull disturbance on the lichen barrens’ recession on this island. Aerial photo analysis showed that the area occupied by lichen barrens declined by 85.5 % from 1967 to 2009, and that it was associated with an advance of vascular plants. The vascular plant species involved in this phenomenon were mainly shrubs (~63 %, Rhododendron groenlandicum and Empetrum nigrum) and herbaceous species (~35 %, Rubus idaeus and Chamerion angustifolium). This decline of the lichen barrens does not seem to be associated with recent climate change as it occurred mainly between 1967 and 1988, a period during which temperatures were relatively stable. Furthermore, the low lichen cover measured around sites disturbed by herring gulls indicates that the disturbances probably occurred after the lichen was replaced by vascular plants, which suggests that these disturbances were not responsible for the observed decline. However, herring gull disturbances seem to favour the development of an herbaceous cover. Besides the loss of lichen species, no negative effects of a vascular plant cover development was observed on the diversity, species richness nor abundance of functional groups. Our results do not allow us to identify the cause of the lichen narrends retreat. A change in soil condition caused by oraganic mater accumulation after the island emergence and permafrost degradation could be implicated, but still need to be investigate.

No / (137)Cs concentrations in ten species of foliose lichens collected within Tsukuba-city in August 2013 ranged from 1.7 to 35 kBq/kg. The relationships between (137)Cs in two dominant species, Dirinaria applanata and Physcia orientalis, and the air dose rate (muSv/h) at the sampling sites were investigated. (137)Cs in P. orientalis measured about 1 year after the Fukushima nuclear accident was correlated (r(2) = 0.80) more closely with the air dose rate than those measured after about 2 years (r(2) = 0.65), possibly demonstrating its continued value as a biomonitor to reflect ambient fall-out levels. In contrast, those of Dirinaria applanata were not correlated with the air dose rate in either year.