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Exploration of Very High Spatial Resolution Data for Vegetation Mapping using Cartographic Ontologies: Identifying Life Forms to Mapping FormationsRodriguez-Gallegos, Hugo Benigno January 2009 (has links)
Vegetation mapping is often considered the process of identifying landscape patterns of individuals or clusters of species or life forms (LF). At the landscape scale, the larger pattern represented by individuals or clusters represents the conceptualization of "vegetation mapping" and can be used as a building block to describe an ecosystem. To represent these building blocks or LF a "common entity (CE)" concept is introduced to represent the components of Formations as described by the National Vegetation Classification (NVC) system. The NVC has established protocols to consistently represent plant communities and promote coordinated management, particularly across jurisdictional boundaries. However, it is not a universal standard and the methods of producing detailed maps of vegetation CE from very high spatial resolution (VHR) remote sensing data are important research questions.This research addressed how best to understand and represent plant cover in arid regions, the most effective methods of mapping vegetation cover using high spatial resolution data, how to assess the accuracy of these maps, and their value in establishing more standardized mapping protocols across ecosystems. Utilizing VHR products from the IKONOS and QuickBird sensors the study focused on the Coronado National Memorial and Chiricahua National Monument in Arizona and Los Ajos and Pinacate - Grand Desierto Biosphere Reserves in México. Individual CE were semi-automatically mapped incorporating spectral, textural and geostatistical variables. The results were evaluated across sensors, study sites, and input variables. In addition, multiple methods of acquiring field data for accuracy assessment were evaluated and then an evaluation was made of a semi-automatic determination of Formation based on CE.The results of the study suggest consistency across study sites using the IKONOSdata. A comparison between VHR products from the same place is feasible but sensor spectral differences may affect which derived bands would improve classification. CE classification procedures were not significantly different across sensors. The overall accuracy obtained for each Park was 59.5% for Chiricahua using QuickBird and 51.9% using IKONOS; at Pinacate 70.0% using IKONOS, and 55.9% for Ajos. Incorporating the geostatistical semi-variogram variables improved CE accuracy for some CE but not all.
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Is Mars Inhabited?Douglass, A.E. 03 1900 (has links)
No description available.
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La problématique de l'identité dans les romans de Sylvie Germain : une approche sémiotique / The issue of identity in Sylvie Germain's novels : a semiotic approachBankir, Seldag 21 December 2017 (has links)
Ce travail vise une exploration du sens autour de l’identité dans les romans de Sylvie Germain qui est une auteure importante de la littérature française contemporaine. L’univers romanesque de l’auteure interroge l’existence humaine et incite le lecteur à se poser des questions sur la vie et l’identité. En mettant en jeu la vie fictive de ses personnages, Sylvie Germain dénonce les contraintes du monde moderne et contemporaine qui provoquent les troubles de l'identité chez les gens. Les romans de notre corpus (“Chanson des Mal-aimants”, “Magnus”, “L’inaperçu”) sont traversés par cette problématique de l’identité qui marque tout le parcours des acteurs-personnages. Dans notre étude, nous nous proposons de mettre en évidence les différents aspects de la problématique identitaire dans une perspective sémiotique. En examinant le dispositif affectif, cognitif et modal des personnages romanesques, nous nous attardons sur leurs rôles et attitudes de façon à relever le changement et la permanence dans leur construction identitaire. Notre étude s’appuie notamment sur l’analyse des “formes de vie” qui déterminent les modes d’existence et de persévérance des personnages dans leur cours de vie marqué par l’incertitude et les obstacles. Notre analyse cherche à déterminer les perturbations qui affectent la construction identitaire des personnages. A travers l’analyse sémiotique qui nous permet d’étudier les différentes dimensions du discours romanesque - narrative, figurative, affective, énonciative-, nous nous proposons de saisir les éléments significatifs concernant la configuration de l’identité dans l’univers romanesque de Sylvie Germain. / This work aims to explore the meaning of identity in the novels of Sylvie Germain, who is an important author of contemporary French literature. The novelistic universe of the author que stions the human existence and encourages the reader to ask questions about life and identity. By putting into play the fictional life of her characters, Sylvie Germain denounces the constraints of the modern and contemporary world that cause identity disorders in people. The novels of our corpus ("The Song of False lovers ", "Magnus", "Hidden Lives") are met by this issue of identity that marks the whole journey of actors-characters. In our study, we propose to highlight the different aspects of the problem of identity in a semiotic perspective. By examining the affective, cognitive and modal features of the fictional characters, we focus on their roles and attitudes in order to identify change and permanence in their identity construction. Our study is based in particular on the analysis of "life forms" which determine the modes of existence and perseverance of the characters in their course of life marked by uncertainty and obstacles. Our analysis seeks to determine the disturbances that affect the identity construction of the characters. Through the semiotic analysis that allows us to study the different dimensions of the novelistic discourse-narrative, figurative, affective, enunciative-we propose to capture the significant elements concerning the configuration of identity in Sylvie Germain’s novel universe.
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Elongation of Scots pine seedlings under blue light depletionSarala, M. (Marian) 14 September 2010 (has links)
Abstract
The elongation response of Scots pine (Pinus sylvestris L.) seedlings to the removal of blue light (400–500 nm) was studied in field experiments in northern Finland. The seedlings were grown in orange or transparent plexiglass chambers or in ambient control plots. The orange plexiglass removed the blue wavelengths from sunlight, while the others served as controls. The experiment was conducted at sub-arctic (69°N) and mid-boreal (64°N) latitudes with three- and two-year-old seedlings originating from 67°N latitude. The response to blue light depletion was also investigated at the 69°N latitude in the following plant subjects: one-year-old Scots pine seedlings of northern (67°N) and southern (62°N) provenances, deciduous Betula pubescens ssp. czerepanovii and Betula pubescens f. rubra seedlings and herbaceous Epilobium angustifolium and Glechoma hederacea plants. Additionally, diurnal change in light quality at the 69°N latitude during the summer was measured.
The elongation of Scots pine seedlings was increased by the removal of blue wavelengths. The increase was more pronounced at the 69°N latitude, while at the 64°N latitude the response was smaller or absent. This is due to increased amount of scattered growth-inhibiting blue light during the nights at the high latitude.
The removal of blue light increased stem elongation in northern origin Scots pine seedlings much more compared to the southern origin seedlings, which suggests that the northern provenance is more sensitive to blue light. Irrespective of that, southern origins also suffer from reduced elongation in the north as they migrate according to climatic change scenarios. However, it is obvious that they grow longer than local origins in the north.
Morphological variables and photosynthetic pigments confirm that the increased elongation of Scots pine seedlings under blue light depletion is not a result of etiolation or it is only a marginal factor. Also, it was neither dependent on temperature nor photosynthesis and growth resources. Instead, the increased elongation is probably a photomorphogenic regulation response of metabolism. In addition, shade intolerant Scots pine, Betula seedlings and herbaceous Epilobium angustifolium responded stronger to blue light removal compared to the more shade-tolerant herbaceous Glechoma hederacea.
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Bryophyte and macrolichen diversity of the Purdiaea nutans forest in southern Ecuador and its relationship to soil, climate and vegetation structure / Bryophyte and macrolichen diversity of the Purdiaea nutans forest in southern Ecuador and its relationship to soil, climate and vegetation structureMandl, Nicole 31 October 2007 (has links)
No description available.
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Andlighet och religiositet på Fryshuset : en inblick i en senmodern och global förändringskontext / Spirituality and religion at Fryshuset : a glimpse of a late modern and global contextKjellsdotter Rydinger, Maria January 2010 (has links)
<p>The aim of this study is to investigate the components of religion and spirituality in the specific context of "Fryshuset" – a multicultural and glocal arena. Against the backdrop of contemporary researchers such as Heelas and Woodhead and their hypothesis about the "spiritual revolution" and a "new spirituality", as well as the postmodern discussion about "the return of God", this study discusses how religious change can be understood in the context of Fryshuset.</p><p>The theoretical point of departure is taken in a hermeneutical method where Fleck´s theory about "thought-collective" and Gidden´s theory about the "duality of structure" are used in order to understand and describe the dialectical relationship between individual and social structure.</p><p>The method used in this study is qualitative. The interviews are made of six individuals representing different social projects at Fryshuset.</p><p>By analyzing the material from the field study through theories on religious change, three areas are identified:</p><ol><li>"The subjective turn"</li><li>Religion and spirituality</li><li>A Cosmopolitan interpretation of life </li></ol><p>The result of this study is that the religiosity among the interviewed can be described through Taylor’s understanding of the "subjective turn". Furthermore they are also part of a "double subjective turn" understood as an internalized subjective turn. Despite the fact that a lot of what the informants describe corresponds to Heelas and Woodheads theories of "subjective life spirituality" it is not relevant to talk about a "spiritual revolution". However, according to Beckford´s theories about religion as a "cultural resource" it can be described as a kind of new spirituality which is used in order to act and think global. The individuals use religion and spirituality as a cultural resource in their formation of a larger cosmopolitan interpretation of life.</p>
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Andlighet och religiositet på Fryshuset : en inblick i en senmodern och global förändringskontext / Spirituality and religion at Fryshuset : a glimpse of a late modern and global contextKjellsdotter Rydinger, Maria January 2010 (has links)
The aim of this study is to investigate the components of religion and spirituality in the specific context of "Fryshuset" – a multicultural and glocal arena. Against the backdrop of contemporary researchers such as Heelas and Woodhead and their hypothesis about the "spiritual revolution" and a "new spirituality", as well as the postmodern discussion about "the return of God", this study discusses how religious change can be understood in the context of Fryshuset. The theoretical point of departure is taken in a hermeneutical method where Fleck´s theory about "thought-collective" and Gidden´s theory about the "duality of structure" are used in order to understand and describe the dialectical relationship between individual and social structure. The method used in this study is qualitative. The interviews are made of six individuals representing different social projects at Fryshuset. By analyzing the material from the field study through theories on religious change, three areas are identified: "The subjective turn" Religion and spirituality A Cosmopolitan interpretation of life The result of this study is that the religiosity among the interviewed can be described through Taylor’s understanding of the "subjective turn". Furthermore they are also part of a "double subjective turn" understood as an internalized subjective turn. Despite the fact that a lot of what the informants describe corresponds to Heelas and Woodheads theories of "subjective life spirituality" it is not relevant to talk about a "spiritual revolution". However, according to Beckford´s theories about religion as a "cultural resource" it can be described as a kind of new spirituality which is used in order to act and think global. The individuals use religion and spirituality as a cultural resource in their formation of a larger cosmopolitan interpretation of life.
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Analyse de la variabilité des traits architecturaux des formes de croissance dans les communautés végétales / Analysis of architectural traits variation in plant communitiesMillan, Mathieu 15 December 2016 (has links)
Les formes de croissance végétales ont fait l'objet de nombreuses études mais elles constituent encore aujourd'hui un ensemble mal défini et sans cesse remis en question en raison de l'incohérence et de l'hétérogénéité des méthodes employées pour les analyser. Cette imprécision a des répercussions négatives lorsque les formes de croissance sont utilisées dans l'étude des communautés végétales et de leur dynamique. Nous avons tenté de remédier partiellement à cette situation en appliquant à certaines d'entre elles la méthode d'analyse architecturale initiée par Hallé et Oldeman dont l'efficacité s'est avérée remarquable pour la compréhension des formes arborescentes.L'étude était destinée 1) à interpréter ces formes de croissance et leur variabilité à l'aide des concepts architecturaux, 2) à suivre les changements des traits architecturaux au sein d'une communauté végétale se développant sur des talus, lors d'une chronoséquence et en fonction de différents gradients environnementaux. Nos observations montrent que 1) les concepts et les traits architecturaux sont applicables aux formes de croissance herbacées, suffrutescentes, et buissonnantes, 2) l'expression de la réitération est la source principale de variation structurale des formes de croissance aussi bien à l'échelle spécifique qu'infra-spécifique, 3) la valeur des traits architecturaux change au cours de la succession au sein de la communauté : les plantes vivant sur des talus jeunes ont une unité architecturale simple et réitèrent à la base alors que celles croissant sur des talus plus anciens ont des unités architecturales complexes et réitèrent de manière acrotone.Ces résultats nous conduisent à discuter de la valeur holistique de la méthode d'analyse architecturale pour la caractérisation des formes de croissance, des processus biologiques permettant de passer d'une forme de croissance à une autre et de l'intérêt pratique de l'utilisation des traits architecturaux dans l'étude des communautés végétales. / The growth forms of plant have been studied many times but they still represent nowadays a fuzzy set, often modified because of the inconsistency and the heterogeneity of the methods used in their analysis. This lack of precision often leads to an inconsistency of the use of the growth forms as a trait in the studies of plants communities and their dynamics. We tried to remedy this situation by applying to some of them the architectural analysis initiated by Hallé and Oldeman, which has been relevant for the understanding of the tree growth form.This study aimed to 1) interpret these growth forms and their variability by means of architectural concepts, 2) study architectural traits variation within roadsides plants communities during succession and in a mowing context. Our resultats show that 1) the architectural concepts and traits are applicable to herbaceous, treelet and bush grosth forms, 2) the expression of the reiteration is the main source of structural variation of growth forms at specific and intraspecific levels and 3) that traits values are changing during succession within the communities : Plants living at early successionnal stages got a simple architectural unit and reiterate at the base of the individual while plants living at late successional stages got complex architectural unit and acrotonic reiteration.These resultats lead us to discuss the holistic value of the architectural analysis for growth forms charaterisation, of biological processes allowing for growth form variation and the interest of the use of architectural traits in plant communities studies.
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Quelle pyrodiversité pour quelle biodiversité ? Une étude comparative multi-échelle de deux écosystèmes méditerranéens / Which pyrodiversity for what biodiversity? A multi-scale comparative study of two Mediterranean ecosystemsFaivre, Nicolas 08 July 2011 (has links)
Contexte & Objectifs. Le feu est une perturbation récurrente dans les écosystèmes méditerranéens et est souvent considéré comme une composante intrinsèque pour le fonctionnement de ces écosystèmes. Cependant, le rôle des incendies de forêt sur la biodiversité reste controversé. Ainsi, bien que la perception de cette perturbation par la communauté scientifique prenne en compte les effets négatifs et positifs, le feu reste pour une grande part de l’opinion publique une catastrophe humaine et environnementale. Mes recherches ont eu pour objectif de quantifier les effets du feu sur la biodiversité végétale dans les écosystèmes à climat méditerranéen en abordant la relation feu-biodiversité à différentes échelles et en particulier en considérant les caractéristiques spatiales et temporelles des mosaïques générées par les feux au niveau du paysage. L’étude a été dupliquée dans deux biomes méditerranéens distincts (France méditerranéenne et Sud-ouest Australien) de sorte à rechercher à travers les différences les patrons de réponse communs.Méthodologie. Généralement, les feux ont été étudiés comme des évènements singuliers dont il convenait de mesurer l’impact sur les écosystèmes. Dans cette étude, les feux ont été considérés comme une succession d’évènements formant au niveau du paysage des mosaïques en s’additionnant dans le temps et en se superposant dans l’espace. La diversité de ces mosaïques a été quantifiée et a permis de définir un nouveau paramètre, la pyrodiversité. Mes recherches proposent une méthodologie objective et adaptée à la caractérisation de la pyrodiversité à l’échelle du paysage. Les patrons de feux, compilés sur 50 ans, ont été analysés et la diversité de la végétation (habitats, espèces et traits fonctionnels) a été échantillonnée en suivant le protocole développé dans le cadre du projet Européen EBONE. En utilisant la même échelle géographique pour croiser patrons de feu et patrons de végétation, il a été possible de relier pyrodiversité et biodiversité et d’examiner cette relation simultanément au niveau de la communauté végétale (habitat) et du paysage (mosaïque d’habitats).Résultats. Cette étude démontre qu’une pyrodiversité élevée (grande variabilité des patrons spatio-temporels des feux à l’échelle du paysage) est associée à des stades de succession de végétation plus variés et de ce fait maximise la diversité des habitats au niveau du paysage. Les résultats acquis permettent de montrer que le feu exerce une influence significative, avec d’autres facteurs comme les conditions environnementales ou l’utilisation du sol, sur la composition des habitats ainsi que sur l’hétérogénéité spatiale de la mosaïque d’habitats au sein du paysage. Que l’on considère les effets du feu sur les espèces végétales ou les traits fonctionnels de ces taxons, mes travaux montrent également que la diversité des plantes vasculaires au niveau de l’habitat varie avec la fréquence des feux suivant l’hypothèse de perturbation intermédiaire. À l’échelle du paysage, la relation pyrodiversité-biodiversité vérifie l’hypothèse de perturbation hétérogène : les maxima de diversité alpha et beta ont été observés lorsque les mosaïques de feux étaient caractérisées par un niveau élevé de pyrodiversité. À l’échelle régionale, la pyrodiversité favorise la diversité des habitats (diversité gamma) jusqu’à un certain seuil. Les deux aires d’étude affichent des profils de pyrodiversité contrastés, du fait de leurs gestions opposées du feu, mais égalemet des flores très contrastées. Il en résulte des différences de résilience et résistance au feu au sein de leurs écosystèmes respectifs. Toutefois, les deux biomes méditerranéens et leur végétation présentent des convergences évidentes dans leurs réponses écologiques au gradient de pyrodiversité.ConclusionsCette étude permet de resituer le rôle du feu et sa contribution à la richesse floristique des écosystèmes méditerranéens. / Aim and Background. Fire is an integral component of Mediterranean type ecosystems and other fire-prone systems worldwide but the perception of fire as an ecological disaster remains a widely-held view among human societies. Understanding whether and to what extent fire is beneficial or detrimental to biodiversity is a current research priority for conservation management in fire-prone systems. My research has attempted to quantify the multi-scale effects of fire on various facets of vegetation diversity, including landscape diversity, taxonomic diversity and functional diversity from a landscape ecology perspective. We used two contrasted Mediterranean study cases i.e., south-eastern France and south-western Australia in order to distinguish from their differences common ecological patterns.Methods. Fires and their effects on vegetation are normally studied as single and localized events. Here, we considered landscape-scale fire mosaics resulting from the compilation of fire events that occurred among time and space in a given landscape. The diversity of those fire mosaics has been quantified and permitted to define a new parameter i.e., pyrodiversity. This research proposes a conceptual and practical methodology for the objective characterization of pyrodiversity based on the comparison of two Mediterranean environments: south-west of Western Australia and southern France. Fire patterns were analyzed retrospectively over a 50-year period while vegetation, habitats and species diversity were quantified at the landscape scale using a monitoring protocol developed within the EBONE EU-project. Using the same geographical scale for fire and vegetation patterns permitted to cross the information on biodiversity and pyrodiversity. The relationship between pyrodiversity and biodiversity was examined at the community level (i.e., habitat) and landscape level (mosaic of habitats) with considering successively habitat diversity, taxonomic diversity and functional diversity.ResultsThis study provides evidence that high pyrodiversity (i.e., spatio-temporal diversity of fire patterns) is associated to various successional trajectories of vegetation and thereby maximizes the diversity of habitats at landscape scale. The results indicate that fire significantly contributes with environmental factors and land management to determine the composition of habitats across a landscape and spatial heterogeneity of landscape mosaics. Whether considering the effects of a single fire event on plant species or on plant functional traits, I found that plant diversity varies with fire frequency according to the intermediate disturbance hypothesis at the habitat level. At the landscape level, the pyrodiversity-biodiversity relationship verified the heterogeneous disturbance hypothesis i.e., maxima of alpha and beta diversity are associated to fire mosaics of high spatiotemporal heterogeneity. At the regional scale, pyrodiversity enhances habitat diversity (gamma diversity) within the landscape until a certain threshold. The two studies areas display contrasting profiles of pyrodiversity due to their different fire management strategies but also exhibit taxonomically unrelated floras. Hence, the two Mediterranean biomes were characterized by different ecosystem resilience and resistance to fire. Despite these differences, the two Mediterranean biomes show convergence trends in their ecological response to the gradient of pyrodiversity.Conclusion. This study tackled the Pyrodiversity-Biodiversity paradigm and demonstrated that Mediterranean-type ecosystems need pyrodiversity to maintain the variety of habitats and species at both habitat and landscape levels. Fire effects on vegetation cannot be interpreted directly from a local perspective with considering a single fire event.
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Vegetação rupestre associada á floresta estacional no sul do BrasilRocha, Fernando Souza January 2009 (has links)
Formações rupestres representam centros de diversidade taxonômica e funcional associadas a condições ambientais extremas. São também sítios para colonização por espécies florestais, normalmente associada a mecanismos de facilitação. A distribuição das espécies, determinada por seu nicho e por mecanismos neutros, resulta na variação da composição entre comunidades (diversidade beta). Neste trabalho pretendemos avaliar se a vegetação rupestre apresenta-se, taxonômica e funcionalmente, distinta da matriz florestal regional, analisar possíveis interações positivas entre espécies associadas ao avanço da floresta sobre a vegetação rupestre e determinar como a composição de espécies arbóreas no gradiente floresta-afloramento rochoso é limitada por dinâmicas neutras, de nicho ou ambas ao longo da ontogenia. Estudamos a vegetação sobre afloramentos basálticos no Parque Estadual do Turvo, sul do Brasil. A flora das comunidades rupestres foi estudada a campo durante dois anos. As espécies foram classificadas em formas de vida com base na literatura e observação no campo. Para avaliarmos a ocorrência de facilitação e os padrões de diversidade beta arbórea amostramos comunidades de espécies arbóreas em três ecótonos de floresta/afloramento rochoso. Em cada sítio estabelecemos 60 parcelas de 1.5 x 1.5 m ao longo do gradiente. As parcelas foram descritas pela cobertura de Bromelia balansae Mez e pela composição de espécies, separadas em quatro classes de tamanho, representando as diferentes fases ontogenéticas dos indivíduos. Avaliamos diferenças taxonômicas e funcionais entre a vegetação rupestre e a flora regional através de testes de qui-quadrado e os efeitos dos diferentes fatores através de testes de aleatorização uni e multivariados. Registramos 111 espécies, das quais 43 de ocorrência restrita aos afloramentos, distribuídas em 54 famílias botânicas. O espectro de formas de vida teve grande frequência de caméfitos (29.7%), nanofanerófitos (17.1%) e geófitos (15.3%). Entre as espécies de ocorrência restrita, geófitos (32.6%), caméfitos (25.6%) e nanofanerófitos (20.9%) como foram as mais frequentes. Testes de 2 indicaram diferenças significativas nas frequências de famílias e de formas de vida entre os ambientes. Nossos resultados indicaram uma associação positiva entre a cobertura de bromélias e a riqueza e a abundância de plântulas de espécies arbóreas. Aparentemente, maiores coberturas por B. balansae fornecem proteção contra a herbivoria, indistintamente, e amenização das severas condições ambientais, favorecendo o estabelecimento de espécies pioneiras da floresta. Os testes multivariados indicaram efeito significativo do fator sítio sobre a diversidade beta, em todas as classes de tamanho, e do fator gradiente somente para duas classes de tamanho analisadas. A vegetação rupestre apresentou uma flora distinta, florística e funcionalmente, com uma grande similaridade a outras formações rupestres neotropicais, mas com expressivo número de espécies arbóreas. Plântulas destas espécies, aparentemente, beneficiam-se da presença de B. balansae, o que pode levar à redução gradual da vegetação rupestre neste mosaico floresta/afloramentos. Entender como as comunidades arbóreas têm sua distribuição determinada por limitações de dispersão e de nicho pode levar a uma melhor compreensão dos processos que geram e mantêm a diversidade. / Rocky outcrops are centers of taxonomic and functional diversity with extreme environmental conditions. They also are sites for colonization by forestry species, usually related to facilitation mechanisms. The species distribution set by niche and neutrals mechanisms results in the variation of composition among communities (beta diversity). The goals of this work are evaluate if rocky outcrops are taxonomically and functionally different from the surrounding forest, study the possible positive interactions among species related to the advance of the forest over the rupestrian vegetation and determine how the composition of arboreal species in the interface forest/rocky outcrop is limited by neutral, niche or both dynamics along the ontogeny. We studied the vegetation of basaltic rocky outcrops at the Turvo State Park, south Brazil. The flora from rupestrian communities was analyzed at field during two years. Species were classified into life forms based on literature and field observations. To evaluate the patterns of arboreal beta diversity and the occurrence of facilitation between plants we sampled arboreal species in three forest/rocky outcrop ecotones. In each rocky outcrop we established 60 plots of 1.5 x 1.5 m along the forest-rocky outcrop ecotone. We described each plot in terms of Bromelia balansae Mez cover and the composition of tree species, separated into four size classes, representing different ontogenetic stages of individuals. The taxonomic and functional differences between the rupestrian vegetation and regional flora were analyzed with the chi-square test and the effects of different factors were analyzed with randomization tests uni-and multivariate. We registered 111 species, 43 of which restricted to the rocky outcrops, distributed in 54 botanic families. The life form spectrum showed a high proportion of chamaephytes (29.7%), nanophanerophytes (17.1%) and geophytes (15.3%). The flora restricted to rocky outcrops showed more frequently geophytes (32.6%), chamaephytes (25.6%) and nanophanerophytes (20.9%). Chi-square tests indicated significant differences in frequencies among environments, for both families and life forms. Our results showed that the coverage of bromeliads is positively correlated to the richness and abundance of seedlings of arboreal species. It seems that higher cover by B. balansae gives protection against herbivory indistinctively, and also reduces the effects of severe environmental conditions, allowing the settlement of forest pioneers species. Multivariate tests showed significant effect of the site factor on the beta diversity in all classes of size and significant effect of the gradient factor only on two size classes evaluated. The rupestrian vegetation is distinct floristically and functionally, showing high floristic similarity with other neotropical rupestrian formations, but has high number of arboreal species. Seedlings of arboreal species seem to have benefit from the presence of B. balansae, which can cause a gradual reduction of the rupestrian vegetation in the forest and rocky outcrop mosaic. Understanding how the distribution of arboreal communities is determined by limitations of dispersal and niche can improve the comprehension of the dynamics that generate and maintain diversity.
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