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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Redes de interação plantas-visitantes florais e a restauração de processos ecológicos em florestas tropicais / Flower- visitor networks and the restoration of ecological processes in tropical forests

Vosgueritchian, Simone Bazarian 17 September 2010 (has links)
A restauração da Mata Atlântica tem sido considerada prioridade nas iniciativas de manutenção da biodiversidade. Adicionalmente, há consenso de que os parâmetros para avaliação da restauração ecológica devem mensurar o retorno de funções ecológicas. O estudo de interações planta-visitante floral pode ser um caminho adequado para avaliar a eficiência das práticas de restauração, visto que estas interações desempenham função crítica na dinâmica e diversidade da comunidade. Variações na diversidade de espécies de plantas e de seus visitantes florais podem alterar a freqüência de interação entre as espécies, definir a estrutura das redes de interação, determinando os níveis de generalização e especialização na comunidade. Neste contexto, a tentativa de restaurar florestas tropicais pela adição de espécies arbóreas pode ter efeitos sobre a estrutura, estabelecimento de grupos funcionais e níveis de generalização na rede de interação entre flores e visitantes florais. O objetivo principal deste trabalho é o de comparar redes de interação planta-visitante floral em florestas tropicais restauradas após 5 anos do plantio das arbóreas, florestas regeneradas naturalmente e remanescentes de floresta atlântica em uma área sob domínio da Mata Atlântica no sudeste do Brasil. Para atingir esse objetivo, essas florestas foram comparadas quanto suas diversidades estruturais e funcionais em relação aos seguintes aspectos: 1) Riqueza e atributos de história de vida (formas de vida, sistemas sexuais, modos de polinização e de dispersão); 2) redes de interação plantavisitante floral; 3) Grau de generalização e especialização das redes de interação; 4) robustez quanto à perda de espécie em redes de interação, e 5) Formação de grupos funcionais seguindo características florais e de freqüência de visitas. Para cada aspecto avaliamos a contribuição das espécies plantadas. Florestas restauradas tiveram a maior riqueza de espécies em flor, porém com menor similaridade florística com outras florestas locais. A similaridade em abundâncias relativas de arbustos e lianas com outras categorias de florestas indicou a inclusão de outras formas de vida além de árvores nas florestas restauradas. Porém, a alta abundância relativa de árvores nas florestas regeneradas naturalmente também indicou o potencial de regeneração natural em florestas 15 degradadas. A maior diversidade de modos de polinização biótica e de dispersão de sementes nas florestas restauradas veio das plantas regenerantes espontaneamente. Não houve diferenças significativas quanto às métricas de redes de interação flores e visitantes entre os tratamentos, porém houve uma tendência de maior especialização dessas interações nas florestas nativas e maior robustez à perda de espécies em florestas restauradas. Além disso, plantas regenerantes espontaneamente receberam significantemente mais visitas nas florestas regeneradas naturalmente do que em florestas restauradas, sugerindo que árvores plantadas podem estar reduzindo visitação às flores da vegetação regenerante espontânea, possivelmente competindo por visitantes florais. Em relação à diversidade funcional, 21 grupos funcionais baseados em atributos florais foram estabelecidos entre todas as espécies em flor, onde as espécies da floresta restaurada dominaram três grandes grupos e a floresta nativa apresentou representantes distribuídos equitativamente pelos grupos, sem dominância. Pólen foi a variável que mais contribui para diferenciação dos grupos. As espécies plantadas formaram grupos funcionais exclusivos nas florestas restauradas, contribuindo para uma maior diversificação em atributos funcionais florais em tais comunidades, porém não mais do que a diversificação funcional trazida pelas plantas regenerantes espontaneamente. Redes de interação entre grupos funcionais de plantas e categorias taxonômicas de visitantes reforçaram que os visitantes florais parecem não seguir fielmente grupos funcionais por atributos florais. Considerando que as florestas regeneradas naturalmente apresentaram alta abundância relativa de árvores, não apresentaram diferenças significativas quanto às métricas de redes de interação planta-visitantes florais com as florestas restauradas e que a regeneração natural na região estudada ocorre em grande intensidade, sugerimos que seja dada importância relevante às plantas regenerantes espontaneamente em projetos de restauração. Cabe ressaltar que avaliamos restauração após 5 anos da implantação. Assim, todas as conclusões tiradas deste estudo necessitarão ser acompanhada em estudos futuros. / Restoration of the Brazilian Atlantic Forest has been considered priority in initiatives to maintain biodiversity. Additionally, there is consensus that the parameters to evaluate restoration should address the return of ecological processes. The study of flower-visitor interactions can be a reasonable way to evaluate restoration practice, considering that these interactions have critical role in the dynamics and diversity of communities. Variations in the diversity of plant species and their flower visitors could modify frequency of interactions between species; define the structure of interaction networks, and determine generalization and specialization levels in the community as well. In this context, the attempt to restore tropical forests by planting native trees can affect the structural and functional diversity and generalization level in flower-visitor networks. The main objective of this research is to compare flower-visitor networks in 5-year-old restored forests, naturally regenerated forests and native forests in an Atlantic Forest domain in southeastern Brazil. We compared these forests in relation to: 1) Richness of species and life history traits (growth form, sexual system, biotic pollination modes and dispersal modes); 2) Flower-visitor networks; 3) Generalization and specialization levels in ecological networks; 4) Robustness to species loss in ecological networks; and 5) Functional groups by floral traits and visitation frequencies of flower visitors. We evaluated the contribution of planted species on each of these aspects. Restored forests had the highest floristic richness of species in flower, but little floristic similarity with other native local forests. Similarity in the relative abundance of shrubs and lianas among habitat categories indicated the possibility of annexation of other life forms than trees in restored forests. But the presence of high relative abundance of trees in the naturally regenerated forests also indicated the potential of natural regeneration of the degraded forests. Biotic pollination and dispersal modes tended to be more diverse in restored forests, but it comes as a result of the addition of spontaneously regenerated plants to this forest. There were no significant differences in the metrics of flower-visitor networks between forest categories, although there was a trend towards high specialization of 17 interactions between flower and visitors in native forests and high robustness of species loss in restored forests. In addition, spontaneously regenerated plants received significantly more visits in the naturally regenerated forests than in restored forests, suggesting that the planted trees may reduce the visitation to the spontaneously regenerated vegetation, possibly by competing for flower visitors. With regard to functional diversity, 21 functional groups based on floral traits were recognized when all species in flower was pooled. Species of restored forests were dispersed mainly among three groups, while species from native forests were spread among all groups with almost the same number of species per group. Pollen was the variable that most contributed for grouping species. Planted trees species formed exclusive functional groups, contributing for higher diversification of floral trait to the community. However, this diversification was not higher than provided by spontaneous regenerated plants. Interaction networks between plant functional groups and taxonomic categories of flower visitors ensured that flower visitors do not seem to follow the grouping formed by floral traits. Considering that naturally regenerated forests had high relative abundance of trees, were not different from restored forests in relation to network metrics and that natural regeneration was intense in the region, we suggest paying relevant attention to spontaneous regenerated plants in restoration projects. We would like to point out that we evaluated five-year-old restored forests and there is still need to track these forests in the future.
12

Fenologia de espécies de floresta atlântica, núcleo Picinguaba, Parque Estadual da Serra do Mar, Estado de São Paulo: comparação entre estratos e influência de borda natural

Gressler, Eliana [UNESP] 30 November 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-30Bitstream added on 2014-06-13T19:40:28Z : No. of bitstreams: 1 gressler_e_dr_rcla_parcial.pdf: 306092 bytes, checksum: 46c6a22ca5b1e53423d1ecb5b439101e (MD5) / A sazonalidade na floração, frutificação e renovação foliar das plantas tropicais tem sido investigada em diferentes níveis de organização, de populações a comunidade, revalando grande diversidade fenológica como resposta à heterogeneidade ambiental das florestas tropicais... / The seasonality in flowering, fruiting and leafing of tropical plants has been investigated at different levels of organization, from populations to the community, showing great diversity of phenological responses to the environmental heterogeneity of tropical forests... (Complete abstract click electronic access below)
13

Assessing factors influencing the spatial distribution of species diversity in ground dwelling ant assemblages in lowland, wet forest of southwest Sri Lanka

Gunawardene, Nihara R January 2008 (has links)
Tropical forests of the world are fast disappearing and there is a race to understand patterns of species distribution in space and time. Studying species distributions can provide better frameworks for conservation of these ecologically important patches of floral and faunal diversity. The island of Sri Lanka is a well known harbour of unique and highly threatened biodiversity. Tropical lowland forest is remnant in the south-west of the island now mainly existing in small patches. While most are small disturbed fragments, Sinharaja Forest Reserve represents one of the largest remaining patches of this important ecosystem. As a UNESCO World Heritage Site and a Man and Biosphere Reserve, it has a dual role as a conservation area and a historically important resource forest. While the distribution of vegetation diversity has been well documented, analyses of invertebrate species distributions are lacking. This thesis investigated a key arthropod group, ground dwelling ants, in relation to environmental gradients within the forest. Cumulative results demonstrate the high diversity of the forest patch. In an area representing less than half the reserve, over 173 ground dwelling ant species were found in distinct assemblages throughout the forest. Since the forest is located upon a series of parallel ridges, ant species distribution was first analysed in terms of this small elevation change. Species richness declined over a vertical incline from 430 m to 660 m, highlighting a possible small-scale, mountain mass effect. This section of the reserve is also characterised by a patch of once-logged forest (30 years previously). A study was undertaken to investigate whether there were residual effects of selective logging on the reserve. / Significant differences between species assemblages in once-logged forest and unlogged forest add to growing evidence that selectively logged forests continue to remain distinct from unlogged forest even after decades of regeneration. Ant distribution was then analysed for their relationship with habitat heterogeneity and tree species distribution. Long-term research on tree species in the SFR has demonstrated a close relationship to habitat complexity. Ant species appear to respond more to the structural heterogeneity of the vegetation than to actual topographic variation within the forest. From a conservation perspective, maintaining the integrity of this highly diverse forest is imperative. The impact of anthropogenic land uses surrounding the forest was investigated in terms of ant assemblages along the forest edges. Significant differences were found between assemblages within the edges bordered by different matrix types. Even relatively large forest remnants can be affected by the surrounding matrix land uses and encouraging the growth of structurally similar vegetation and maintaining low disturbance along the borders should attenuate the effect of the edge. Overall, the highly heterogeneous distribution of ant assemblages within the SFR demonstrates the potential for other small patches to be harbours of further species diversity. Future research should be undertaken to assess the diversity and distribution of ant species within this region and encourage the protection of this remnant diversity.
14

Rainfall redistribution and change of water quality in tropical forest canopies : patterns and persistence

Zimmermann, Alexander January 2009 (has links)
Motivations and research objectives: During the passage of rain water through a forest canopy two main processes take place. First, water is redistributed; and second, its chemical properties change substantially. The rain water redistribution and the brief contact with plant surfaces results in a large variability of both throughfall and its chemical composition. Since throughfall and its chemistry influence a range of physical, chemical and biological processes at or below the forest floor the understanding of throughfall variability and the prediction of throughfall patterns potentially improves the understanding of near-surface processes in forest ecosystems. This thesis comprises three main research objectives. The first objective is to determine the variability of throughfall and its chemistry, and to investigate some of the controlling factors. Second, I explored throughfall spatial patterns. Finally, I attempted to assess the temporal persistence of throughfall and its chemical composition. Research sites and methods: The thesis is based on investigations in a tropical montane rain forest in Ecuador, and lowland rain forest ecosystems in Brazil and Panama. The first two studies investigate both throughfall and throughfall chemistry following a deterministic approach. The third study investigates throughfall patterns with geostatistical methods, and hence, relies on a stochastic approach. Results and Conclusions: Throughfall is highly variable. The variability of throughfall in tropical forests seems to exceed that of many temperate forests. These differences, however, do not solely reflect ecosystem-inherent characteristics, more likely they also mirror management practices. Apart from biotic factors that influence throughfall variability, rainfall magnitude is an important control. Throughfall solute concentrations and solute deposition are even more variable than throughfall. In contrast to throughfall volumes, the variability of solute deposition shows no clear differences between tropical and temperate forests, hence, biodiversity is not a strong predictor of solute deposition heterogeneity. Many other factors control solute deposition patterns, for instance, solute concentration in rainfall and antecedent dry period. The temporal variability of the latter factors partly accounts for the low temporal persistence of solute deposition. In contrast, measurements of throughfall volume are quite stable over time. Results from the Panamanian research site indicate that wet and dry areas outlast consecutive wet seasons. At this research site, throughfall exhibited only weak or pure nugget autocorrelation structures over the studies lag distances. A close look at the geostatistical tools at hand provided evidence that throughfall datasets, in particular those of large events, require robust variogram estimation if one wants to avoid outlier removal. This finding is important because all geostatistical throughfall studies that have been published so far analyzed their data using the classical, non-robust variogram estimator. / Motivation und Zielsetzung: Wenn Regen durch ein Kronendach fällt lassen sich zwei Prozesse beobachten: das Regenwasser wird umverteilt und die chemische Qualität des Wassers verändert sich erheblich. Die Prozesse im Kronenraum resultieren in einer hohen Variabilität des Bestandsniederschlags und dessen chemischer Zusammensetzung. Bestandsniederschlag beeinflusst eine Reihe von physikalischen, chemischen und biologischen Prozessen am Waldboden. Daher können Untersuchungen zur Variabilität und zu Mustern im Bestandsniederschlag helfen, bodennahe Prozesse besser zu verstehen. Diese Dissertation behandelt hauptsächlich drei Aspekte. Erstens, die Arbeit beschäftigt sich mit der Erfassung der Variabilität im Bestandsniederschlag und dessen chemischer Zusammensetzung, zudem werden Einflussfaktoren dieser Variabilität untersucht. Des Weiteren beschäftigt sich die Arbeit mit räumlichen Mustern des Bestandsniederschlagswassers, und drittens wird die zeitliche Stabilität des Bestandsniederschlags und dessen chemischer Zusammensetzung betrachtet. Untersuchungsgebiete und Methoden: Diese Dissertation basiert auf Untersuchungen in einem tropischen Bergregenwald in Ecuador, sowie Studien in tropischen Tieflandregenwäldern in Brasilien und Panama. Die ersten zwei Studien untersuchen Bestandsniederschlag und dessen chemische Zusammensetzung mit Hilfe deterministischer Methoden. Die Arbeit in Panama nutzt geostatistische Methoden zur Beschreibung von Bestandsniederschlagsmustern und verfolgt somit einen stochastischen Ansatz. Ergebnisse und Schlussfolgerungen: Die Variabilität des Bestandsniederschlages ist hoch; das heißt, die Menge des auf den Waldboden tropfenden Wassers kann sich je nach Standort stark unterscheiden. Diese räumliche Variabilität des Bestandsniederschlags ist in tropischen Wäldern höher als in vielen gemäßigten Waldökosystemen, was nicht allein auf verschiedenen Eigenschaften der Ökosysteme zurückzuführen ist. Vielmehr erklären sich die Unterschiede auch aus verschiedenen Waldnutzungen. Abgesehen von biologischen Faktoren beeinflusst die Regenmenge die Variabilität des Bestandsniederschlags erheblich. Die chemische Zusammensetzung des Bestandsniederschlags weist eine noch höhere Variabilität als der Bestandsniederschlag selbst auf. Unterschiede zwischen tropischen und gemäßigten Wäldern lassen sich hier allerdings nicht erkennen, weshalb die hohe Diversität tropischer Ökosysteme die Heterogenität der chemischen Zusammensetzung des Bestandsniederschlags nicht ausreichend erklärt. Eine Vielzahl anderer Faktoren kontrolliert deshalb die Variabilität der Bestandsniederschlagschemie, beispielsweise die Konzentration gelöster Stoffe im Regenwasser oder die Dauer von Trockenperioden. Deren hohe temporale Variabilität ist verantwortlich für die geringe zeitliche Stabilität von Depositionsmessungen. Im Gegensatz dazu ist die temporale Persistenz von Messungen der Bestandsniederschlagsmenge hoch. Insbesondere die Ergebnisse aus Panama zeigen, dass feuchte und trockene Messpunkte über einen Zeitraum von zwei Regenzeiten fortbestehen. Die räumlichen Bestandsniederschlagsmuster im letztgenannten Untersuchungsgebiet sind schwach bzw. weisen die Struktur eines reinen Nugget-Models auf. Die geostatistische Analyse zeigt, dass vor allem die Daten großer Regenereignisse eine robuste Modellierung des Variogramms erfordern, wenn die willkürliche Entfernung von Fernpunkten in den Daten vermieden werden soll. Dieses Resultat ist insbesondere deshalb von Bedeutung, da alle bisherigen Bestandsniederschlagsstudien den klassischen, nicht-robusten Schätzer benutzen, obwohl das Auftreten von Extremwerten in Bestandsniederschlagsdaten für viele Ökosysteme zu erwarten ist.
15

Changes in cloudiness over tropical land during the last decades and its link to global climate change

Arias, Paola Andrea 19 November 2008 (has links)
Tropical forests play a key role in determining the global carbon-climate feedback in the 21st century. Changes in rainforest growth and mortality rates, especially in the deep and least perturbed forest areas, have been consistently observed across global tropics in recent decades. Understanding the underlying causes of these changes, especially their links to the global climate change, is especially important in determining the future of the tropical rainforests in the 21st century. Previous studies have mostly focused on the potential influences from elevated atmospheric CO2 and increasing surface temperature. Because the rainforests in wet tropical region are often light limited, we explore whether cloudiness have changed, and if so, whether it is consistent with what is expected from changes in forest growth rate.
16

Characterization of forest tree seed quality with near infrared spectroscopy and multivariate analysis /

Tigabu, Mulualem, January 2003 (has links) (PDF)
Diss. (sammanfattning). Umeå : Sveriges lantbruksuniv., 2003. / Härtill 7 uppsatser.
17

Land use dynamics, tree diversity and local perception of dry forest decline in southern Burkina Faso, West Africa /

Paré, Souleymane, January 2008 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2008. / Härtill 4 uppsatser.
18

Fenologia de espécies de floresta atlântica, núcleo Picinguaba, Parque Estadual da Serra do Mar, Estado de São Paulo : comparação entre estratos e influência de borda natural /

Gressler, Eliana. January 2010 (has links)
Orientador: Leonor Patricia Cerdeira Morellato / Banca: Marco Aurelio Pizo Ferreira / Banca: Maria Rosângela Sigrist / Banca: Marcia Cristina Mendes Marques / Banca: Luciano Elsinor Lopes / Resumo: A sazonalidade na floração, frutificação e renovação foliar das plantas tropicais tem sido investigada em diferentes níveis de organização, de populações a comunidade, revalando grande diversidade fenológica como resposta à heterogeneidade ambiental das florestas tropicais... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The seasonality in flowering, fruiting and leafing of tropical plants has been investigated at different levels of organization, from populations to the community, showing great diversity of phenological responses to the environmental heterogeneity of tropical forests... (Complete abstract click electronic access below) / Doutor
19

Dinâmica da sucessão liquênica : padrões estruturais e funcionais como indicadores de regeneração florestal

Koch, Natália Mossmann January 2012 (has links)
A estrutura e a dinâmica da vegetação de uma floresta refletem a complexa interação entre eventos de distúrbios e processos de regeneração que atuam em múltiplas escalas temporais e espaciais. Compreender como esses processos ocorrem é de extrema importância para a conservação e o manejo das florestas. Os liquens são organismos sensíveis às mudanças ambientais, e constituem boas alternativas para o entendimento das alterações que ocorrem na floresta durante o processo de sucessão. O acesso a essas alterações pode ser feito tanto a partir da composição e riqueza de espécies dos liquens, como de atributos funcionais comuns entre diferentes espécies, abordagem que permite comparar comunidades com biogeografias distintas. Frente a isso, esta dissertação tem como objetivos principais (i) determinar os padrões estruturais da sucessão liquênica, quanto a composição, cobertura e riqueza de espécies, ao longo do gradiente de sucessão florestal, (ii) verificar a influência do ambiente e do espaço na variação das comunidades de liquens e as relações entre características ambientais dos estágios sucessionais com a composição e a taxa de substituição de espécies, (iii) determinar os padrões de organização funcional das comunidades de liquens durante a regeneração da floresta, (iv) verificar a diversidade funcional dessas comunidades e (v) verificar a possibilidade da utilização de atributos funcionais de liquens como indicadores dos estágios de sucessão florestal. Um total de 188 táxons de liquens foram amostrados em 24 unidades amostrais, divididas em três estágios de sucessão (6-10; 12-20; e 40-60 anos de regeneração após o abandono). Os resultados corroboram a hipótese principal de que as comunidades de liquens se modificam tanto estrutural quanto funcionalmente, conforme a estrutura da floresta se altera ao longo do gradiente de sucessão. Há mudanças na composição, riqueza de espécies e quanto aos atributos funcionais, estes últimos relacionados ao tipo morfológico e a algumas estruturas reprodutivas. Além disso, os resultados indicam menor turnover de espécies dentro das unidades amostrais dos estágios avançados, uma taxa maior de diversidade beta entre unidades mais distintas ao longo do gradiente de sucessão florestal e maior explicação do ambiente na variação da composição. Comunidades de liquens em florestas tropicais respondem, portanto, às modificações resultantes da sucessão ecológica, e podem servir como uma ferramenta na caracterização de áreas em estágios de regeneração e/ou conservação distintos. Esses resultados reforçam a importância dos liquens como bioindicadores das condições florestais. / Vegetation structure and dynamics in a forest reflect the complex interaction between disturbance events and regeneration processes which may act in several scales, such as temporal and spatial. In order to improve forest conservation and management, it is extremely important to comprehend how these processes occur in nature. Lichens, which are sensitive to environmental changes, are good alternatives for the understanding of forest changes due to forest succession. These changes may be acessed from lichen composition and lichen species richness, as well as from lichen functional traits, which makes possible to compare communities with distinct biogeography. Therefore, this Master’s Thesis has as main objectives to (i) determine structural patterns of lichen succession, based on composition, cover and species richness along the forest succession gradient, (ii) verify environmental and spatial influence in lichen community variation and the relation among successional stages environmental characteristics with composition and species turnover rate, (iii) determine patterns of functional organization of lichen communities during forest regeneration, (iv) verify the functional diversity of these communities and (v) verify the possibilty of using lichens functional traits as indicators of forest succession stages. A total of 188 lichen taxa were sampled in 24 sampling sites, which were split into three succession stages (from 6-10; 12-20; and 40-60 years of regeneration after being abandoned). Results confirm the main hypothesis that lichen communities change as forest structure changes along the successional gradient, regarding their structure and also functionally. There are changes in composition, species richness and functional traits, these traits related to lichen growing forms and to some reproductive structures. Besides, results also indicate less species turnover in older sampling sites, a greater beta diversity rate among more distinct sampling sites along forest succession gradient and a higher environmental explanation in composition variation. Lichen communities in tropical forests are therefore showing changes due to forest succession and may be used as another tool in characterizing areas in distinct stages of regeneration and/or conservation. These results also reinforce the importance of using lichens as bioindicators of forest conditions.
20

Dinâmica da sucessão liquênica : padrões estruturais e funcionais como indicadores de regeneração florestal

Koch, Natália Mossmann January 2012 (has links)
A estrutura e a dinâmica da vegetação de uma floresta refletem a complexa interação entre eventos de distúrbios e processos de regeneração que atuam em múltiplas escalas temporais e espaciais. Compreender como esses processos ocorrem é de extrema importância para a conservação e o manejo das florestas. Os liquens são organismos sensíveis às mudanças ambientais, e constituem boas alternativas para o entendimento das alterações que ocorrem na floresta durante o processo de sucessão. O acesso a essas alterações pode ser feito tanto a partir da composição e riqueza de espécies dos liquens, como de atributos funcionais comuns entre diferentes espécies, abordagem que permite comparar comunidades com biogeografias distintas. Frente a isso, esta dissertação tem como objetivos principais (i) determinar os padrões estruturais da sucessão liquênica, quanto a composição, cobertura e riqueza de espécies, ao longo do gradiente de sucessão florestal, (ii) verificar a influência do ambiente e do espaço na variação das comunidades de liquens e as relações entre características ambientais dos estágios sucessionais com a composição e a taxa de substituição de espécies, (iii) determinar os padrões de organização funcional das comunidades de liquens durante a regeneração da floresta, (iv) verificar a diversidade funcional dessas comunidades e (v) verificar a possibilidade da utilização de atributos funcionais de liquens como indicadores dos estágios de sucessão florestal. Um total de 188 táxons de liquens foram amostrados em 24 unidades amostrais, divididas em três estágios de sucessão (6-10; 12-20; e 40-60 anos de regeneração após o abandono). Os resultados corroboram a hipótese principal de que as comunidades de liquens se modificam tanto estrutural quanto funcionalmente, conforme a estrutura da floresta se altera ao longo do gradiente de sucessão. Há mudanças na composição, riqueza de espécies e quanto aos atributos funcionais, estes últimos relacionados ao tipo morfológico e a algumas estruturas reprodutivas. Além disso, os resultados indicam menor turnover de espécies dentro das unidades amostrais dos estágios avançados, uma taxa maior de diversidade beta entre unidades mais distintas ao longo do gradiente de sucessão florestal e maior explicação do ambiente na variação da composição. Comunidades de liquens em florestas tropicais respondem, portanto, às modificações resultantes da sucessão ecológica, e podem servir como uma ferramenta na caracterização de áreas em estágios de regeneração e/ou conservação distintos. Esses resultados reforçam a importância dos liquens como bioindicadores das condições florestais. / Vegetation structure and dynamics in a forest reflect the complex interaction between disturbance events and regeneration processes which may act in several scales, such as temporal and spatial. In order to improve forest conservation and management, it is extremely important to comprehend how these processes occur in nature. Lichens, which are sensitive to environmental changes, are good alternatives for the understanding of forest changes due to forest succession. These changes may be acessed from lichen composition and lichen species richness, as well as from lichen functional traits, which makes possible to compare communities with distinct biogeography. Therefore, this Master’s Thesis has as main objectives to (i) determine structural patterns of lichen succession, based on composition, cover and species richness along the forest succession gradient, (ii) verify environmental and spatial influence in lichen community variation and the relation among successional stages environmental characteristics with composition and species turnover rate, (iii) determine patterns of functional organization of lichen communities during forest regeneration, (iv) verify the functional diversity of these communities and (v) verify the possibilty of using lichens functional traits as indicators of forest succession stages. A total of 188 lichen taxa were sampled in 24 sampling sites, which were split into three succession stages (from 6-10; 12-20; and 40-60 years of regeneration after being abandoned). Results confirm the main hypothesis that lichen communities change as forest structure changes along the successional gradient, regarding their structure and also functionally. There are changes in composition, species richness and functional traits, these traits related to lichen growing forms and to some reproductive structures. Besides, results also indicate less species turnover in older sampling sites, a greater beta diversity rate among more distinct sampling sites along forest succession gradient and a higher environmental explanation in composition variation. Lichen communities in tropical forests are therefore showing changes due to forest succession and may be used as another tool in characterizing areas in distinct stages of regeneration and/or conservation. These results also reinforce the importance of using lichens as bioindicators of forest conditions.

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