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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.
181

Optimal Monitoring and Harvesting of a Wild Population Under Uncertainty

Hauser, Cindy Emma Unknown Date (has links)
No description available.
182

Population and behavioral ecology of water monitor lizard (Varanus salvator)

Ahmad, A. Unknown Date (has links)
No description available.
183

Optimal Monitoring and Harvesting of a Wild Population Under Uncertainty

Hauser, Cindy Emma Unknown Date (has links)
No description available.
184

Adhesion and autoaggregation of Lactobacillus reuteri and description of a new lactobacillus species with mucus binding properties /

Roos, Stefan, January 1900 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
185

Natura 2000 : kooperatives Vorgehen von Gemeinschaft und Mitgliedstaaten bei der Errichtung eines Netzes von Schutzgebieten zum Zwecke des Artenschutzes /

Wichert, Friedrich. January 2001 (has links) (PDF)
Univ., Diss.--Freiburg (Breisgau), 2001. / Literaturverz. S. [181] - 186.
186

L'horizon autobiographique du récit de voyage de Flora Tristan, Les pérégrinations d'une paria (1838)

Malenfant, Brigitte, January 1997 (has links)
Thèses (M.A.)--Université de Sherbrooke (Canada), 1997. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.
187

Zur Silphionfrage

Strantz, Else, January 1909 (has links)
Thesis (doctoral)--Universität Zürich. / Bibliography: p. [i]-xii.
188

Phoenix Four River Flora

January 2011 (has links)
abstract: ABSTRACT The Phoenix Four Rivers Flora is an inventory of all the vascular plants growing along the Salt, Gila, New and Agua Fria Rivers, and their tributaries in the Phoenix Metropolitan Area during the years of the study (2009-2011). This floristic inventory documents the plant species and habitats that exist currently in the project area, which has changed dramatically from previous times. The data gathered by the flora project thus not only documents how the current flora has been altered by urbanization, but also will provide a baseline for future ecological studies. The Phoenix Metropolitan Area is a large urbanized region in the Sonoran Desert of Central Arizona, and its rivers are important for the region for many uses including flood control, waste water management, recreation, and gravel mining. The flora of the rivers and tributaries within the project area is extremely diverse; the heterogeneity of the systems being caused by urbanization, stream modification for flood control, gravel mining, and escaped exotic species. Hydrological changes include increased runoff in some areas because of impermeable surfaces (e.g. paved streets) and decreased runoff in other areas due to flood retention basins. The landscaping trade has introduced exotic plant species that have escaped into urban washes and riparian areas. Many of these have established with native species to form novel plant associations. / Dissertation/Thesis / M.S. Plant Biology 2011
189

Florística e estrutura da vegetação em Cerrado sentido restrito no Parque Estadual de Terra Ronca, Goiás : método RAPELD

Teixeira, Ana Magalhães Cordeiro 10 September 2015 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Biologia, Departamento de Botânica, Programa de Pós-Graduação em Botânica, 2015. / Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2016-01-27T16:49:58Z No. of bitstreams: 1 2015_AnaMagalhãesCordeiroTeixeira.pdf: 4745136 bytes, checksum: 37983bd1c3a9166d2be2602854386eea (MD5) / Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2016-01-27T19:52:02Z (GMT) No. of bitstreams: 1 2015_AnaMagalhãesCordeiroTeixeira.pdf: 4745136 bytes, checksum: 37983bd1c3a9166d2be2602854386eea (MD5) / Made available in DSpace on 2016-01-27T19:52:02Z (GMT). No. of bitstreams: 1 2015_AnaMagalhãesCordeiroTeixeira.pdf: 4745136 bytes, checksum: 37983bd1c3a9166d2be2602854386eea (MD5) / Este estudo teve como objetivo caracterizar a flora e a estrutura do Cerrado sentido restrito sobre Neossolo Quartzarênico no Parque Estadual de Terra Ronca - PETeR, localizado na região nordeste do estado de Goiás. Pretendeu-se, também, avaliar o método RAPELD utilizado para amostrar a vegetação arbustivo-arbórea em Cerrado sentido restrito. No capítulo 1, a flora foi amostrada a partir de três transecções de 5 Km. Registramos 222 espécies, sendo que nove representam novas ocorrências para o estado de Goiás e duas para o bioma Cerrado. Dentre as espécies registradas, 28% são endêmicas do Cerrado e 72% são compartilhadas com outros domínios fitogeográficos. O maior compartilhamento ocorreu com a Caatinga, o que demonstra o aspecto transicional com este domínio. A elevada similaridade florística com os cerrados da Bahia e do norte de Minas Gerais confirmam a afinidade da flora do PETeR com a província fitogeográfica norte-nordeste. No capítulo 2, a estrutura da vegetação arbustivo-arbórea foi analisada em duas classes de tamanho distintas - a classe 1 inclui indivíduos com diâmetro entre 2 e 5 cm e foi amostrada em oito parcelas de 4 x 250 m; a classe 2 engloba os indivíduos com diâmetro maior que 5 cm e foi amostrada em oito parcelas de 20 x 250 m. A partir da comparação da flora e dos parâmetros estruturais entre as classes sugerimos que pode haver redução no número de espécies que compõe a classe 2. Os valores de densidade (403 ind.ha-1), área basal (5,31 m2.ha-1), riqueza (43) e diversidade (2,80) registrados na classe 2 foram os mais baixos quando comparados com outras áreas de Cerrado sentido restrito sobre Neossolo Quartzarênico. Esses resultados associados à análise da ocorrência de fogo na área de estudo, nos últimos 20 anos, nos permite sugerir que a vegetação lenhosa está sendo negativamente influenciada pela elevada frequencia de incêndios. Nesse sentido, ressaltamos que o controle e o manejo do fogo devem ser priorizados nas ações de manejo do PETeR a fim de garantir a conservação da flora nativa. Por fim, no capítulo 3, a comparação do protocolo de amostragem do método RAPELD (MR) com o protocolo do método de parcelas permanentes (MPP), subsidiou a avaliação do desempenho do MR aplicado à vegetação arbustivo-arbórea em Cerrado sentido restrito. Além disso, avaliamos o impacto da redução de 50% do esforço amostral sobre as estimativas dos parâmetros fitossociológicos, de riqueza e diversidade de espécies, obtidas por meio do MR. A utilização do MPP resultou em estimativas dos parâmetros estruturais semelhantes ao MR. Além disso, o MPP foi mais eficiente para estimar a riqueza e a diversidade de espécies e apresentou menor tempo de execução. Dessa forma, se o propósito do levantamento é conhecer a composição de espécies, a riqueza, a diversidade e a estrutura da vegetação, recomendamos a adoção do MPP. Por outro lado, se a pesquisa tem como objetivo analisar a interação da flora com outros grupos taxonômicos, o MR deve ser utilizado, pois possibilita o levantamento de dados de táxons distintos utilizando a mesma estrutura de amostragem. A redução de 50% do esforço amostral na amostragem do MR não alterou significativamente as estimativas dos parâmetros florísticos e estruturais da vegetação. Portanto, o esforço amostral do MR deve se reduzido pela metade a fim de otimizar a relação custo-benefício deste método de amostragem. / This study aimed to characterize structure and flora of Cerrado sensu stricto in Terra Ronca State Park – PETeR. The aim was also to evaluate the RAPELD method used to sample shrub and tree vegetation in Cerrado sensu stricto. PETeR is located in northeastern of Goiás state, on Tocantins River basin. In chaptear 1, flora was sampled based on three 5 Km transects. We recorded 222 species, nine represent new records for Goiás state and two for the Cerrado biome. Among the recorded species, 28% are endemic to Cerrado and 72% are shared with other phytogeographic domains. The highest share occurred with Caatinga, showing the transitional aspect with this domain. The high floristic similarity with Cerrados from Bahia and north of Minas Gerais confirmed the affinity of PETeR flora with north-northeast phytogeographic province. In chapter 2, the structure of shrub-tree vegetation was analyzed in two different size classes - class 1 includes individuals with diameter between 2 and 5 cm and was sampled in eight plots of 4 x 250 m; class 2 comprises individuals with diameter above 5 cm and was sampled in eight plots of 20 x 250 m. By comparing flora and structural parameters between classes, we suggest that there will probably happens a reduction in number of species from class 2. Density (403 ind.ha-1), basal area (5.31 m2.ha-1), richness (43) and diversity (2.80) values registered in class 2 were the lowest when compared to other areas of Cerrado sensu stricto on Quartzipsamment. These results associated with fire occurrence analysis in study area, on last 20 years, allow us to suggest that woody vegetation is being negatively influenced by the high frequency of fires. Thus, we emphasize that the control and fire management must have priority in PETeR management actions in order to ensure the conservation of native flora. In chapter 3 the evaluation of RAPELD method (MR) applied to sample shrub and tree vegetation in Cerrado sensu stricto was carried out by comparing the sampling protocol of MR with permanent plots protocol (MPP), proposed by Cerrado and Pantanal Permanent Plots Network. We assess the efficiency of these methods for estimating phytosociological parameters, floristic composition, richness and diversity of species in community. In addition, we evaluated the 50% reduction of sampling effort on estimates obtained using the MR. The use of MPP resulted in structural parameters similar to MR. In addition, the MPP was more efficient to estimate richness and diversity of species and had lower running cost. Thus, if the purpose of the survey is to know species composition, richness, diversity and vegetation structure, we recommend the adoption of MPP. On the other hand, if the aim of the research is to analyze the flora interaction with other taxonomic groups, the MR should be used, because it allows the survey of distinct taxa using the same sampling frame. The 50% reduction of sampling effort in MR didn’t significantly change the floristic and structural parameters estimates. Therefore, the MR sample effort should be halved in order to optimize the cost-benefit ratio of this sampling method.
190

Conserving the biodiversity of Kuwait through DNA barcoding the flora

Abdullah, Mansour Taleb January 2017 (has links)
Biodiversity across the globe is threatened. Rapid surveying and monitoring techniques are required to understand the origin of the threats to biodiversity and to enable conservation actions to be undertaken. Kuwait is an arid desert country with a small flora of only 402 species. This flora is endangered by environmental factors, overgrazing, and human activities. DNA barcoding the flora and using Next Generation Sequencing (NGS) technologies allowed us to identify plants to species level, conduct a molecular taxonomic revision, and distinguish plant diversity found in soil environmental DNA samples. After investigating the discriminatory power of five commonly used DNA markers from plastid (matK, rbcL, trnH-psbA, trnL) and a nuclear genome (ITS2) on four largest genera of the flora using phylogenetics reconstruction tree based methods, two barcoding markers (rbcL and ITS2) were assigned to build a DNA reference library of the flora. Furthermore, the DNA reference library was tested to identify the plant diversity found below-ground level and comparing it with that above-ground, using environmental soil samples collected from both species rich and poor habitats in Kuwait by applying high-throughput sequencing methods. The DNA database provided in this study could be used as a reference library for the identification process and contribute towards the future of molecular taxonomy, biodiversity and ecological research in Kuwait.

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