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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

Change in deciduous woody vegetation, implications of increased willow (Salix spp.) growth for bird species diversity, and willow species composition in and around Yellowstone National Park's Northern range

Baril, Lisa Marie. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Andrew J. Hansen. Includes bibliographical references.
52

Características físicas do lenho em grupos fenológicos foliares de arbóreas de cerrado

Venancio, Natalia Cristina 10 October 2016 (has links)
Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2017-08-28T14:07:07Z No. of bitstreams: 1 DissNCV.pdf: 1386182 bytes, checksum: 58b2a2b04857f39a3f3fc9209b911165 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-09-06T13:29:17Z (GMT) No. of bitstreams: 1 DissNCV.pdf: 1386182 bytes, checksum: 58b2a2b04857f39a3f3fc9209b911165 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-09-06T13:29:27Z (GMT) No. of bitstreams: 1 DissNCV.pdf: 1386182 bytes, checksum: 58b2a2b04857f39a3f3fc9209b911165 (MD5) / Made available in DSpace on 2017-09-06T13:36:09Z (GMT). No. of bitstreams: 1 DissNCV.pdf: 1386182 bytes, checksum: 58b2a2b04857f39a3f3fc9209b911165 (MD5) Previous issue date: 2016-10-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Leaf phenological groups of cerrado tree species show significant differences not only concerning the maintenance of foliage throughout the year but also about reproductive phenology as the peak and duration of flowering. In addition to the vegetative and reproductive phenology, deciduous (DE) semideciduous (SD) and evergreen (EV) cerrado trees have canopy architecture and the type of branching and leaf production significantly different. Therefore, the structure and functionality of wood probably show significant differences in these three groups (DE, SD, and EV). We aimed to determine the physical characteristics of wood and their relationships in aerial and underground parts of DE, SD, and EV tree species of cerrado vegetation. Internal (density, porosity, and water storage capacity) and external (crown height and root depth) physical traits of wood were determined in species distributed in DE, SD, and EV in two stages of development: adult and in the initial growth. By sections of the trunk at the transition between aerial and underground portions, we obtained results from bark and trunk in studied leaf phenological groups. There was a significant difference between DE and EV in a functional gradient where we found SD species. This group showed similar values to DE or EV species or even significantly different from both groups depending on the analyzed trait. Thus, the species distributed in leaf phenological groups also differed significantly in internal and external physical characteristics of wood in branches, in the transition from aerial to aboveground part and underground portion. These results indicated species grouped by leaf phenology have several other physical characteristics significantly different. Therefore, leaf phenological groups of cerrado trees are, in fact, functional groups. It has been successfully used to show that leaf phenology is just one attribute among many others traits distributed in the canopy, stem, and root assembling tree species of cerrado in at least three functional groups. Therefore, regardless the phylogenetic relatedness in each foliar phenological group these species belong to a functional group. Adults DE species growing under natural conditions are taller and have branches less dense and with more imbibition capacity than EV species. Conversely, in early years of growth DE were still taller with a deeper root system but with branches, stem and roots less dense than EV species. The inversion of wood internal traits between DE-EV demonstrated that the strategies for the acquisition and use of resources changed during tree development. It resulted in adult individuals significantly different and these changes probably depended on the biomass accumulated (size) in cerrado trees. The identification of these functional groups of trees is useful for more efficient management of protected areas or for recovering degraded areas of cerrado vegetation. The functional groups of cerrado trees could be identified not only by a list of attributes significantly different but by the reliance among these traits. These relationships built up a particular syndrome in each functional group. Syndromes originated through compromises among characteristics result in specific skills for acquisition, use and storage resources in every tree functional group. These skills result in similar survival strategies (reproduction, growth, and defense) and responses to environmental stresses in each of these functional groups of tree species of the cerrado vegetation. / Grupos fenológicos foliares de espécies arbóreas de cerrado apresentam diferenças significativas não só com relação à manutenção da folhagem ao longo do ano, mas também em relação à fenologia reprodutiva como o pico e a duração da floração. Além da fenologia vegetativa e reprodutiva, decíduas (DE) semidecíduas (SD) e sempre verdes (SV) arbóreas do cerrado apresentam uma arquitetura da copa e um tipo de produção de ramos e folhas significativamente diferentes. Portanto, a estrutura e a funcionalidade do lenho provavelmente também apresentam diferenças significativas nesses 3 grupos. Os objetivos desse trabalho foram determinar características físicas e suas inter-relações no lenho da parte aérea e subterrânea de espécies DE, SD e SV arbóreas do cerrado. Características físicas internas (densidade, porosidade e capacidade de armazenamento de água) e externas (altura da copa e profundidade das raízes) do lenho foram determinadas em várias espécies arbóreas DE, SD e SV adultas e na fase inicial de crescimento. Por meio da obtenção de secções transversais do tronco na altura do colo da planta determinamos também características físicas da casca e do lenho nessa região de transição da porção aérea e subterrânea nos 3 grupos fenológicos foliares. Ocorreu uma significativa diferenciação entre DE e SV para a maioria das variáveis estudadas em um provável gradiente funcional onde transitam as espécies SD. Esse grupo mostrou valores similares às DE, ou às SV ou ainda significativamente diferentes de ambos os grupos dependendo da característica analisada. As espécies distribuídas nos grupos fenológicos foliares, portanto, mostraram diferenças significativas quanto às características físicas internas e externas do lenho na parte aérea, na transição da parte aérea e na porção subterrânea. Esses resultados indicam que as espécies agrupadas por meio da fenologia foliar apresentam várias outras características físicas do lenho significativamente diferentes destacando que os grupos fenológicos foliares são, de fato, grupos funcionais. Independente da proximidade filogenética entre as espécies a fenologia foliar foi usada com sucesso para demonstrar que essa característica é apenas mais um atributo entre muitos outros distribuídos na copa, no caule e na raiz que agrupam espécies arbóreas do cerrado em ao menos 3 grupos funcionais. DE adultas crescendo em condições naturais são significativamente mais altas e apresentam um lenho nos ramos mais poroso, com maior capacidade de embebição e menor densidade que as espécies SV. Nos primeiros anos de crescimento em campo as DE também se mostraram mais altas com um sistema radicular mais profundo, mas com ramos, caule na altura do colo e raízes mais densos, menos porosos e com menor capacidade de embebição que as SV. A inversão das características internas do lenho entre os grupos funcionais nas diferentes fases do ciclo de vida demonstrou que as estratégias de aquisição e uso dos recursos são alteradas durante o desenvolvimento resultando, ao final, em adultas distribuídas em grupos funcionais significativamente diferentes. Essa inversão de características entre as fases de crescimento provavelmente depende da biomassa acumulada (tamanho) do indivíduo nas arbóreas do cerrado. A identificação desses grupos funcionais de arbóreas por meio de suas estratégias de aquisição, uso e estoque de recursos pode ser utilizada para um manejo mais eficiente de áreas protegidas ou na recuperação de áreas degradas do cerrado. Os grupos funcionais de árvores do cerrado puderam ser identificados não só por uma lista de atributos significativamente diferentes, mas por inter-relações de dependência entre esses atributos. Essas relações de dependência formam síndromes características em cada grupo funcional. As síndromes originadas por meio dos compromissos entre as características resultam em competências específicas para a aquisição, uso e estoque de recursos em cada grupo funcional. Essas competências conferem estratégias de sobrevivência (reprodução, crescimento, defesa) resultando necessariamente em respostas similares aos estresses ambientais em cada um desses grupos funcionais de espécies arbóreas do cerrado.
53

Anatomia comparada da casca de stryphnodendron polyphyllum mart. (fabaceae) em cerrado sensu stricto e mata de galeria / Comparative bark anatomy of stryphnodendron polyphyllum mart. (fabaceae) in cerrado sensu stricto and gallery forest

Vergílio, Paula Cristina Benetton [UNESP] 23 January 2015 (has links) (PDF)
Made available in DSpace on 2015-05-14T16:53:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-23Bitstream added on 2015-05-14T16:59:15Z : No. of bitstreams: 1 000829636.pdf: 1079152 bytes, checksum: 3d6200cb153a36d501e804ecf12dc319 (MD5) / O cerrado abrange diversas fitofisionomias, dentre elas, o cerrado sensu stricto, que é uma formação savânica onde há a ocorrência de fogo e o solo é mais pobre em nutrientes, e a mata de galeria, que é uma formação florestal onde não ocorre o fogo e o solo é mais rico em nutrientes. Nós hipotetizamos que a casca das árvores do cerrado sensu stricto é mais larga (proteção ao fogo) e tem um maior grau de escleromorfia nas suas células (solo mais pobre). Para testar essas hipóteses nós comparamos populações de Stryphnodendron polyphyllum Mart. (Fabaceae) em cerrado sensu stricto e mata de galeria. Para tal, coletamos amostras de ramos de indivíduos adultos de S. polyphyllum, realizamos a extração e dosagem de fenóis totais da casca, confeccionamos lâminas permanentes e semipermanentes da casca, e analisamos os aspectos qualitativos e quantitativos da casca. Não houve variações nos aspectos qualitativos da casca entre as populações, podendo ser usados para fins taxonômicos. Já, os aspectos quantitativos apresentaram variações entre as populações. A população do cerrado sensu stricto apresentou valores maiores na largura e proporção do ritidoma e valores menores na largura e proporção do floema secundário condutor, nos diâmetros da fibra e do elemento de tubo crivado e na altura dos raios. Essas diferenças evidenciam as estratégias de cada população, sendo que a casca população do cerrado sensu stricto se caracteriza pela proteção contra fogo e pela segurança na condução de fotoassimilados; e a casca da população da mata de galeria se caracteriza pela eficiência na condução de fotoassimilados. Não encontramos diferenças nem quanto à largura da casca e nem quanto ao grau de escleromorfia nas células da casca entre as populações estudadas. / The cerrado covers various vegetation types, among them, the cerrado sensu stricto, which is a savanna types where has the fire occurrence, and it has poorer soil, and the gallery forest, which is a forest type where has not the fire occurence, and it has rich soil. We hypothesized that the cerrado sensu stricto trees has ticker bark (fire protection), and it has a higher degree of scleromorphism into its cells (poorer soil). To test these hypotheses we compared populations of Stryphnodendron polyphyllum Mart. (Fabaceae) in both cerrado sensu stricto and gallery forest. We collected branche samples of adult trees of S. polyphyllum, and we performed the extraction and quantification of total phenols from the bark, and we made permanent and semipermanent bark slides, and we analyze the qualitative and quantitative bark aspects. The qualitative bark aspects did not show any variation between both populations, and it can be used for taxonomic purposes. The quantitative aspects showed variations between both populations. The cerrado sensu stricto population showed higher values in the width and proportion of rhytidome; and lower values in the width and proportion of conducting secundary phloem, and in the fiber diameter, and in the sieve element diameter, and in rays height. These differences highlight the strategies of each population. The feature bark of cerrado sensu stricto population is the fire protection, and phloem conductivity safety. The feature bark of gallery forest population is the phloem conductivity efficiency. We do not found differences neither of width and proportion bark, nor of degree of scleromorphic into bark cells between the study populations.
54

Anatomia comparada da casca de stryphnodendron polyphyllum mart. (fabaceae) em cerrado sensu stricto e mata de galeria /

Vergílio, Paula Cristina Benetton, 1988. January 2015 (has links)
Orientador: Carmen Regina Marcati / Banca: Silvia Rodrigues Machado / Banca: Cliavia Carolina Fiorilo Possobom / Resumo: O cerrado abrange diversas fitofisionomias, dentre elas, o cerrado sensu stricto, que é uma formação savânica onde há a ocorrência de fogo e o solo é mais pobre em nutrientes, e a mata de galeria, que é uma formação florestal onde não ocorre o fogo e o solo é mais rico em nutrientes. Nós hipotetizamos que a casca das árvores do cerrado sensu stricto é mais larga (proteção ao fogo) e tem um maior grau de escleromorfia nas suas células (solo mais pobre). Para testar essas hipóteses nós comparamos populações de Stryphnodendron polyphyllum Mart. (Fabaceae) em cerrado sensu stricto e mata de galeria. Para tal, coletamos amostras de ramos de indivíduos adultos de S. polyphyllum, realizamos a extração e dosagem de fenóis totais da casca, confeccionamos lâminas permanentes e semipermanentes da casca, e analisamos os aspectos qualitativos e quantitativos da casca. Não houve variações nos aspectos qualitativos da casca entre as populações, podendo ser usados para fins taxonômicos. Já, os aspectos quantitativos apresentaram variações entre as populações. A população do cerrado sensu stricto apresentou valores maiores na largura e proporção do ritidoma e valores menores na largura e proporção do floema secundário condutor, nos diâmetros da fibra e do elemento de tubo crivado e na altura dos raios. Essas diferenças evidenciam as estratégias de cada população, sendo que a casca população do cerrado sensu stricto se caracteriza pela proteção contra fogo e pela segurança na condução de fotoassimilados; e a casca da população da mata de galeria se caracteriza pela eficiência na condução de fotoassimilados. Não encontramos diferenças nem quanto à largura da casca e nem quanto ao grau de escleromorfia nas células da casca entre as populações estudadas. / Abstract: The cerrado covers various vegetation types, among them, the cerrado sensu stricto, which is a savanna types where has the fire occurrence, and it has poorer soil, and the gallery forest, which is a forest type where has not the fire occurence, and it has rich soil. We hypothesized that the cerrado sensu stricto trees has ticker bark (fire protection), and it has a higher degree of scleromorphism into its cells (poorer soil). To test these hypotheses we compared populations of Stryphnodendron polyphyllum Mart. (Fabaceae) in both cerrado sensu stricto and gallery forest. We collected branche samples of adult trees of S. polyphyllum, and we performed the extraction and quantification of total phenols from the bark, and we made permanent and semipermanent bark slides, and we analyze the qualitative and quantitative bark aspects. The qualitative bark aspects did not show any variation between both populations, and it can be used for taxonomic purposes. The quantitative aspects showed variations between both populations. The cerrado sensu stricto population showed higher values in the width and proportion of rhytidome; and lower values in the width and proportion of conducting secundary phloem, and in the fiber diameter, and in the sieve element diameter, and in rays height. These differences highlight the strategies of each population. The feature bark of cerrado sensu stricto population is the fire protection, and phloem conductivity safety. The feature bark of gallery forest population is the phloem conductivity efficiency. We do not found differences neither of width and proportion bark, nor of degree of scleromorphic into bark cells between the study populations. / Mestre
55

The effects of carrier, formulation of phytocide, and time of treatment on the reactions of certain woody plants to chemical sprays

Carter, Mason C. January 1956 (has links)
no abstract provided by author / Master of Science
56

Comprehensive lists of woody plant materials for specific landscape uses in northeast Texas, including Dallas County

Fisher, George Morris. January 1959 (has links)
Call number: LD2668 .T4 1959 F53
57

Species Ranges, Richness and Replacement of Trees in the Evergreen Forests of the Western Ghats

Page, Navendu January 2015 (has links) (PDF)
It has been more than two centuries since the latitudinal pattern of increase in taxonomic richness from poles to equator was first documented. After two centuries of research, and with more than two dozen hypotheses proposed, an understanding of the mechanisms underlying this pattern and their relative importance remains incomplete. Factors such as evolutionary history, area and latitude associated variables such as temperature, solar energy, climatic stability and seasonality are known to influence species richness by affecting geographic range size and location over ecological and evolutionary time. Understanding the forces that affect geographic range size is, therefore, integral to our understanding of latitudinal patterns in species richness. Using woody plants as a study system, my dissertation deciphers the latitudinal pattern, if any, in species richness within the evergreen forests of the Western Ghats. These wet evergreen forests form an evolutionarily distinct biogeographic zone, which has remained isolated from its counterparts. This has resulted in a high percentage of endemism among the evergreen woody plants and, therefore, the global geographic ranges of most of these plants are restricted within the boundaries of the Western Ghats. The first main objective of this dissertation is to understand the determinants of geographic range size in the evergreen woody plants of the Western Ghats. Further, the Western Ghats are characterized by a sharp climatic gradient in temperature and rainfall seasonality that is not correlated with mean annual temperature or annual rainfall. This allows a direct test of the hypotheses and predictions that are based on climatic seasonality, without the confounding effect of other climatic correlates of latitude. Therefore, the second main objective of this dissertation is to understand the mechanisms underlying latitudinal patterns in species richness of evergreen woody plants in the Western Ghats. Regional species richness is an outcome of two factors- local species richness of each location within the region and turnover in species composition among the locations, which in turn are a result of patterns in range size, range location and range overlap. To address these two objectives, I first test the effect of climatic niche of a species in determining geographic range size and then examine the effect of latitude associated climatic seasonality on range location and range overlap. Next, I link the observed pattern in range geometry to latitudinal patterns in species turnover and finally to latitudinal patterns in species richness. While the first part of my dissertation study deals with factors that generate spatial variation in species richness, the second part deals with the factors underlying spatial variation in species composition. Environmental heterogeneity and dispersal are considered the most important determinants of species turnover i.e. change in species composition. However, their relative importance in structuring in diverse plant communities within tropical regions across different scales is poorly understood. Hence, the third objective of this dissertation is to understand the processes that influence change in species composition of woody plants within the Western Ghats. Geographic range size and population size are important attributes of species rarity, which are directly linked to their extinction risk. Hence, data on distribution and population status of species can help us focus our efforts on those species that require conservation attention. This is achieved through carrying out species threat assessments based on attributes such as range and population size and then assigning then to a threat category. A majority of species endemic to the Western Ghats have not yet been assessed, largely due to lack of data on their population and distribution status. Therefore, the fourth and the final part of my dissertation explores the application of information on species range size and abundance in prioritizing species for conservation. To address these objectives, I sampled the wet evergreen forests of the Western Ghats along a series of locations distributed across its entire latitudinal gradient. Based on 156 plots, covering a latitudinal gradient of more than 1200 km and comprising of more than 20,000 occurrence locations belonging to more than 450 species of woody plants, I derived quantitative estimates of latitudinal gradients in range size, local and regional richness as well as species turnover. I used a combination of statistical and simulation approaches to discern the mechanisms underlying large-scale pattern in species ranges, richness and turnover. My dissertation is structured as follows.
58

Arboretum domácích druhů dřevin Týn nad Vltavou / Arboretum of native woody plants Týn nad Vltavou

ŠÍMA, Jaroslav January 2015 (has links)
Thesis contains a design of the arboretum of native woody plants of Czech Republic, which should be placed in the area of the Natural History Museum Semenec in Tyn nad Vltavou. Its aim is to introduce diversity of Czech trees and shrubs species. The arboretum is arranged so as to present particular vegetation zones. This indicator appears in terms of popular scientific mission of the arboretum as the most obvious and comprehensible. Special sections of arboretum are devoted to the azonal communities including those that develops in terms of marginal hydric series. Created arboretum of native woody plants of Czech Republic will serve to general public (tourists, school groups, univerzity students etc.) in the implementation of science educational programs
59

Swamp-Grown Eastern White Pine and Hemlock in Connecticut as Dendrochronological Material

Lutz, H. J. 04 1900 (has links)
No description available.
60

Tree-Ring Research in the Netherlands

Eckstein, D., Brongers, J. A., Bauch, J. January 1975 (has links)
Two independent local tree-ring chronologies of oak in the Netherlands are described. Chronology I contains recent wood, wood from mills, and paintings. This chronology begins in A.D. 1973 and goes back to 1385 and is thought to be from inland areas of the Netherlands and the adjacent German area. Chronology 11 is built up from paintings and sculptures and ranges from A.D. 1623 to 1140; the origin of the wood is presumed to be from a coastal site in the Netherlands.

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