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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.
51

Revisão taxonomica e analise cladistica do genero Dichorisandra J.C. Mikan (Commelinaceae) / Taxonomic revision and cladistic analysis of Dichorisandra

Aona, Lidyanne Yuriko Saleme 31 January 2008 (has links)
Orientador: Maria do Carmo Estanislau do Amaral / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T18:13:00Z (GMT). No. of bitstreams: 1 Aona_LidyanneYurikoSaleme_D.pdf: 61203004 bytes, checksum: a647955fc5bcfd2da8ffaf424a76fedb (MD5) Previous issue date: 2008 / Resumo: Dichorisandra é o maior gênero da subtribo Dichorisandrinae, essencialmente neotropical e caracterizado pelas anteras de deiscência poricida ou rimosa e funcionalmente poricida e sementes ariladas. São ervas perenes, eretas ou escandentes, às vezes com folhas em rosetas próximas ao solo, ocupando, principalmente, o interior de matas. A última revisão de Dichorisandra tem mais de 110 anos e o objetivo principal do presente trabalho foi elaborar a revisão taxonômica do gênero, avaliando novas coletas e espécies que foram descritas desde então. O estudo taxonômico foi realizado a partir de material depositado em herbários nacionais e internacionais e provenientes de coletas principalmente dos Estados de Minas Gerais, Rio de Janeiro, Espírito Santo e Bahia. Os 63 binômios até então publicados foram reduzidos a 30 espécies. São propostas 24 sinonimizações novas e uma nova combinação. Também estão sendo propostas 24 espécies provenientes do Brasil (a maioria delas da Bahia), Panamá, Equador, Peru e Guiana Francesa. Além da revisão taxonômica, foi realizada a análise cladística do gênero Dichorisandra a partir de caracteres morfológicos e macromoleculares (trnL-F, rsp 16 e rpl 16) visando investigar as relações de parentesco entre as espécies e reavaliar o potencial de caracteres morfológicos na identificação de espécies. As matrizes foram analisadas sob o critério de parcimônia. Os clados não são fortemente sustentados na análise de 'bootstrap¿ e a extrema variação de caracteres morfológicos encontrada dentro do gênero demonstra a dificuldade na definição de grupos monofiléticos / Abstract: The neotropical genus Dichorisandra is the largest within the subtribe Dichorisandrinae, being characterized by its poricidal anthers (sometimes opening by slits but functionally poricidal) and its arillated seeds. The plants are perennial, herbaceous, sometimes with a leaf rosette close to the ground, and live mostly within forests. The last revision of the genus dates from over 110 years ago, and the present work aims to present an up-to-date revision for the genus, evaluating a large volume of new records, including the taxa described after fhe first revision was published. The taxonomic studies were based on material held in national and international herbaria and field work focussing the particularly species rich Brazilian states of Minas Gerais, Rio de Janeiro, Espírito Santo and Bahia. The 63 published names were reduced to 30 accepted species, and 24 synonymies and a new combination are proposed. Twenty four new species from Brasil (mostly from Bahia), Panama, Ecuador, Peru and French Guiana were discovered. Apart from the taxonomic revision, a cladistic analysis of the genus was performed with basis on morphologic and macromolecular characters (trnL-F intergenic spacer, rsp 16 and rpl 16 introns) aiming to investigate the species relationships and the re-evaluation of the morphological characters used to determine the species. The matrixes obtained were analyzed under the criterium of parcimony. The clades within the genus are not strongly supported in the 'bootstrap¿ analysis, as the extreme morphological variation found amongst and within species has made it very difficult to define monophyletic groups / Doutorado / Doutor em Biologia Vegetal
52

DNA barcoding Medicinal plants of South Africa.

Mankga, Ledile Thabitha 24 July 2013 (has links)
M.Sc. (Botany) / The market and public demand for medicinal plants over the past few decades has increased dramatically with more than 1 000 plant species actively traded for medicinal purposes throughout South Africa. Intensive harvesting of wild material is now acknowledged as a serious threat to biodiversity in this country. Also the substitution of a valuable commodity (medicinal plant) by a cheaper alternative (other plant species), either inadvertently due to misidentification, or deliberately to cheat consumers, raises some serious concerns as these adulterants may not be as effective or may even be toxic and cause harm to consumers. To add to the problem many species are either traded as dried leaf, root, bark products, or extracts and their identification becomes problematic. Therefore, DNA barcoding can help to provide a rapid and accurate identification tool for medicinal plants. In the current study I targeted the most commonly used medicinal plants in South Africa and produced a set of barcodes for fast and easy DNA-based species identification (rbcLa & matK). I tested the efficiency of core barcodes in the identification of medicinal plants using four main analyses, in the R package Spider 1.1-1. Here the extent of specific genetic divergence, DNA barcoding gap, BLAST test, and the ability to discriminate between species were assessed. Overall, the matK region was found to be a more useful tool for the species identification of medicinal plants in South Africa.
53

Revisão taxonômica e análises filogenéticas das espécies extra-amazônicas de Goeppertia Nees, clado Breviscapus (Marantaceae) /

Saka, Mariana Naomi. January 2016 (has links)
Orientador: Julio Antonio Lombardi / Coorientador: Finn Borchsenius / Banca: Pedro Luis Rodrigues de Moraes / Banca: Fábio Pinheiro / Banca: Lívia Godinho Temponi / Banca: Rafaela Campostrini Forzza / Resumo: Este trabalho está estruturado em dois capítulos, a saber: 1. "Revisão taxonômica das espécies extra-amazônicas de Goeppertia Nees, clado Breviscapus (Marantaceae)"; e 2. "Estudos filogenéticos em Goeppertia e biogeografia do clado Breviscapus em áreas extra-amazônicas". No primeiro capítulo, é apresentada uma revisão taxonômica das espécies extra-amazônicas de Goeppertia pertencentes ao clado Breviscapus. O gênero Goeppertia compreende cerca de 250 espécies de um clado segregado do gênero Calathea. O clado Breviscapus é um grupo heterogêneo, abrigando espécies de várias seções taxonômicas e grupos morfológicos informais. A partir de excursões de campo, análise de espécimes depositados em herbários nacionais e internacionais, e revisão bibliográfica, 70 espécies de distribuição extra-amazônica foram consideradas. São apresentadas chaves de identificação para os grupos de Goeppertia e para as espécies tratadas, descrições e figuras contendo fotografias e mapas de distribuição, quando possíveis. Lectotipificações, neotipificações, sinonimizações e treze novas espécies são indicados, a serem designados ou publicados futuramente. Cerca de 40 espécies se enquadram em alguma categoria de ameaça de acordo com os critérios analisados. No segundo capítulo, foi realizada uma filogenia datada para a família Marantaceae e para o gênero Goeppertia, com enfoque nas espécies extra-amazônicas. Objetivando uma maior compreensão da história biogeográfica das espécies do clado Breviscapus, uma ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work provides a taxonomic study of the species of the family Lauraceae that occurs at Reserva Natural Vale in Linhares, ES, located at north of the State, within the Atlantic Forest biome. An analysis was conducted with all Lauraceae specimens collected in the Reserve that are housed at the herbaria CVRD and HRCB, totalizing ca. 700 exsiccatae. The research recorded 54 species, distributed in 14 genera: Aiouea (one species), Aniba (three species), Beilschmiedia (one species), Cassytha (one species), Cinnamomum (two species), Cryptocarya (three species), Endlicheria (one species), Licaria (two species), Mezilaurus (one species), Nectandra (four species), Ocotea (32 species), Persea (one species), Rhodostemonodaphne (one species) and Urbanodendron (one species). For all species, descriptions, discussions and comments about their morphology, geographic distribution, phenology, uses, and vernacular names are provided, as well as the images of their flowers and floral parts. Furthermore, an interactive key has been built for the identification of such species, by using 229 morphological characters subdivided into 598 states, which were taken from their descriptions. This key has proven to be an efficient tool for identifying either the species of the Reserve or those with a broader distribution. For a group of such complexity, importance, abundance and richness, it is desirable to have devices that facilitate the identification of species, the key being one of them / Doutor
54

Classification of natural forest communities of coastal British Columbia

Klinka, Karel January 2001 (has links)
Vegetation science, like any science, uses classification to organize knowledge about plants and plant communities. Classification is helpful for understanding how different plant communities relate to one another and their environments, for facilitating further studies of vegetation, and for conservation. To familiarize onself with vegetation of a large area, it is very convenient and efficient to begin with a few general units, such as plant orders rather than with many very detailed units, such as plant associations and subassociation. We offer such an approach and think that the information given in this series will be sufficient to assign any forested coastal community to one the orders or suborders. In spite of a history of vegetation studies in British Columbia, there has not yet been any attempt to develop a comprehensive hierarchical classification of plant communities for the province. As the culmination of fifty years of detailed surveys carried out by V.J. Krajina and his students, the Ecology Program Staff of the BC Forest Service, and other workers, we used tabular and multivariate analyses of 3,779 sample plots established in natural, old-growth, submontane, montane, and subalpine forest communities in coastal BC to develop a hierarchy of vegetation units according to the methods of biogeoclimatic ecosystem classification.
55

Relações filogeneticas e diversificação no complexo 'Maxillaria Madida' (Maxillariinae:Orchidaceae) / Phylogenetic relationships and diversification within the 'Maxillaria madida' complex (Maxillariinae:Orchidaceae)

Koehler, Samantha, 1975- 20 April 2007 (has links)
Orientador: Maria do Carmo Estanislau do Amaral / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T06:25:59Z (GMT). No. of bitstreams: 1 Koehler_Samantha_D.pdf: 6443365 bytes, checksum: 6a01c884fb24c1fbf015cf1b2ab4e212 (MD5) Previous issue date: 2007 / Resumo: Não informado / Abstract: Not informed. / Doutorado / Biologia Vegetal / Mestre em Biologia Vegetal
56

Eficácia de medidas de similaridade para a classificação de séries temporais associadas ao comportamento fenológico de plantas / Eficácia de medidas de similaridade para a classificação de séries temporais associadas ao comportamento fenológico de plantas

Conti, José Carlos, 1966- 12 November 2013 (has links)
Orientadores: Luiz Camolesi Júnior, Ricardo da Silva Torres / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-24T02:27:51Z (GMT). No. of bitstreams: 1 Conti_JoseCarlos_M.pdf: 2108170 bytes, checksum: 16e7093192986c856bf2d3675ef2a605 (MD5) Previous issue date: 2013 / Resumo: Fenologia é o estudo de fenômenos naturais periódicos e sua relação com o clima. Nos últimos anos, tem se apresentado relevante como o indicador mais simples e confiável dos efeitos das mudanças climáticas em plantas e animais. É nesse contexto que se destaca o e-phenology, um projeto multidisciplinar envolvendo pesquisas na área de computação e fenologia. Suas principais características são: o uso de novas tecnologias de monitoramento ambiental, o fornecimento de modelos, métodos e algoritmos para apoiar o gerenciamento, a integração e a análise remota de dados de fenologia, além da criação de um protocolo para um programa de monitoramento de fenologia. Do ponto de vista da computação, as pesquisas científicas buscam modelos, ferramentas e técnicas baseadas em processamento de imagem, extraindo e indexando características de imagens associadas a diferentes tipos de vegetação, além de se concentrar no gerenciamento e mineração de dados e no processamento de séries temporais. Diante desse cenário, esse trabalho especificamente, tem como objetivo investigar a eficácia de medidas de similaridade para a classificação de séries temporais sobre fenômenos fenológicos caracterizados por vetores de características extraídos de imagens de vegetação. Os cálculos foram realizados considerando regiões de imagens de vegetação e foram considerados diferentes critérios de avaliação: espécies de planta, hora do dia e canais de cor. Os resultados obtidos oferecem algumas possibilidades de análise, porém na visão geral, a medida de distância Edit Distance with Real Penalty (ERP) apresentou o índice de acerto mais alto com 29,90%. Adicionalmente, resultados obtidos mostram que as primeiras horas do dia e no final da tarde, provavelmente devido à luminosidade, apresentam os índices de acerto mais altos para todas as visões de análise / Abstract: Phenology is the study of periodic natural phenomena and their relationship to climate. In recent years, it has gained importance as the more simple and reliable indicator of effects of climate changes on plants and animals. In this context, we emphasizes the e-phenology, a multidisciplinary research project in computer science and phenology. Its main characteristics are: The use of new technologies for environmental monitoring, providing models, methods and algorithms to support management, integration and remote analysis of data on phenology, and the creation a protocol for a program to monitoring phenology. From the computer science point of view, the e-phenology project has been dedicated to creating models, tools and techniques based on image processing algorithms, extracting and indexing image features associated with different types of vegetation, and implementing data mining algorithms for processing time series. This project has as main goal to investigate the effectiveness of similarity measures for the classification of time series associated with phenological phenomena characterized by feature vectors extracted from images. Conducted experiments considered different regions containing individuals of different species and considering different criteria such as: plant species, time of day and color channels. Obtained results show that the Edit Distance with Real Penalty (ERP) distance measure yields the highest accuracy. Additionally, the analyzes show that in the early morning and late afternoon, probably due to light conditions, it can be observed the highest accuracy rates for all views analysis / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia
57

The vegetation of Breslau Game Farm, Northern Province, South Africa

Straub, Andrea Frances 10 October 2007 (has links)
Please read the abstract (Summary)in the section 08summary of this document / Dissertation (MSc (Botany))--University of Pretoria, 2002. / Please note that Chapter 2 is removed due to sensitive information / Plant Science / MSc / Unrestricted
58

Le genre Psychotria (Rubiaceae) en Afrique occidentale et centrale: taxonomie, phylogénie et biogéographie / Genus Psychotria (Rubiaceae) in West and Central Africa: taxonomy, phylogeny and biogeography

Lachenaud, Olivier 11 September 2013 (has links)
Le genre Psychotria est le plus vaste de la famille des Rubiaceae, avec plusieurs centaines d’espèces répandues dans toutes les régions tropicales humides. Les Psychotria sont principalement des arbustes (quelques-uns sont lianescents, herbacés ou arborescents) et entrent souvent pour une part importante dans la composition des sous-bois tropicaux. Certains montrent des adaptations remarquables comme la symbiose bactérienne foliaire ou l’accumulation d’humus. En raison de sa taille et des difficultés d’identifications, ce genre reste mal connu, notamment en Afrique occidentale et centrale où il n’a fait l’objet d’aucun travail d’ensemble depuis les années 1960.<p>Le présent travail a pour objectifs :1) la révision taxonomique du genre Psychotria pour l’Afrique occidentale et centrale; 2) une étude phylogénétique du genre, visant à reconstituer son évolution et améliorer la classification infragénérique ;et 3) une étude biogéographique régionale de ce groupe, afin de définir des centres de diversité et d'endémisme.<p>Notre travail de taxonomie, fondé sur l’examen des spécimens d’herbier et sur des missions de terrain au Cameroun et au Gabon, nous a conduit à reconnaître l’existence de 232 espèces en Afrique occidentale et centrale, ce qui fait de Psychotria le plus vaste genre de plantes dans cette région. Parmi ces espèces, 78 sont nouvelles.<p>Nos travaux phylogénétiques, basés sur l’étude de deux marqueurs nucléaires (ITS et ETS) et quatre chloroplastiques (rps16, trnG, matK et rbcLa), montrent que la classification de Petit (1964, 1966) est largement à revoir. Il apparaît notamment que les deux sous-genres (Psychotria et Tetramerae) reconnus en Afrique, et fondés sur la présence ou l’absence de nodules bactériens foliaires, ne sont pas monophylétiques, certaines espèces ayant secondairement perdu leurs nodules. Nos résultats soutiennent également le rattachement du genre monospécifique Peripeplus à Psychotria.<p>Le genre Psychotria montre une diversité remarquable, associée à un taux d’endémisme élevé, dans le domaine bas-guinéen (Cameroun et Gabon principalement) où plusieurs centres d’endémisme ont été identifiés. Ceux-ci sont localisés non seulement dans les massifs montagneux de l’intérieur, dont la flore particulière est bien connue, mais également dans les régions littorales. L’Afrique de l’ouest, moins diversifiée, montre cependant un fort endémisme localisé principalement dans deux centres, l’un situé au Liberia et dans l’ouest de la Côte d’Ivoire, l’autre vers la frontière Côte d’Ivoire/Ghana. Le bassin du Congo, comparable en diversité à l’Afrique de l’Ouest, est relativement pauvre en endémiques.<p>Ces résultats suggèrent que les forêts du Cameroun et du Gabon auraient relativement bien résisté aux périodes sèches passées, et remettent notamment en question l’hypothèse d’une disparition des forêts littorales du golfe de Guinée au cours du Pleistocène./Psychotria is the largest genus in the Rubiaceae family, with several hundred species in wet tropical areas worldwide. Psychotria spp. are mostly shrubs (a few being lianas, creepers or trees) and are often an important component of the undergrowth in tropical rainforests. Some show remarkable adaptations such as leaf bacterial symbiosis or litter gathering. Due to its size and identification problems, Psychotria remains a little-known genus, especially in West and Central Africa, where no major work has been done on this group since the 1960s.<p>The aims of the present work are: 1) a taxonomic revision of Psychotria in West and Central Africa; 2) a phylogenetic study of the genus, in order to trace its evolution and improve the infrageneric classification; and 3) a regional biogeographic study of the genus, to define centers of diversity and endemism.<p>Our taxonomical work, based on the study of herbarium specimens and field expeditions in Gabon and Cameroon, led us to recognise 232 species of Psychotria in West and Central Africa. Psychotria is therefore the largest plant genus in this area. Among these species, 78 are new.<p>Our phylogenetic work, based on two nuclear markers (ITS and ETS) and four chloroplastic markers (rps16, trnG, matK, rbcLa), shows that Petit’s (1964, 1966) infrageneric classification is in need of revision. In particular, we show that the two subgenera present in Africa (subg. Tetramerae and subg. Psychotria), which are defined by the presence or absence of leaf bacterial nodules, are not monophyletic: a secondary loss of the bacterial nodules has occured in some species. Our results also support the merging of the monospecific genus Peripeplus into Psychotria.<p>The genus Psychotria shows a remarkable diversity and a high level and endemism in the Lower Guinea domain (particularly Cameroon and Gabon) where several centers of endemism are identified. These are located not only in the inland hill ranges, which are well known for their particular flora, but also in littoral areas. West Africa is less diverse but also shows a high level of endemism, which concerns mostly two areas, one in Liberia and western Côte d’Ivoire and the other around the Côte d’Ivoire/Ghana border. The Congo basin, comparable in diversity to West Africa, has relatively few endemic species.<p>These results suggest that the rainforests of Cameroon and Gabon resisted relatively well during historical drier periods. They do not support the hypothesis of a disappearance of the Gulf of Guinea littoral forests during the Pleistocene.<p><p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

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