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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

The three-dimensional orientation of gaps has species-dependent effects on bridging performance and gap choice of arboreal snakes

Hoefer, K. Marie 08 October 2012 (has links)
No description available.
12

Locomotion, Morphology, and Habitat use in Arboreal Squirrels (Rodentia: Sciuridea)

Essner, Richard L., Jr. January 2003 (has links)
No description available.
13

Efeito do sombreamento sobre a fotossíntese e mortalidade em espécies não arbóreas do cerrado stricto sensu. /

Marroni, Guilherme Genova de January 2019 (has links)
Orientador: Rosana Marta Kolb / Resumo: O Cerrado é considerado o segundo maior bioma brasileiro em extensão, com ampla diversidade de espécies e endemismo. Nas últimas décadas, áreas de Cerrado vêm sofrendo alterações fitofisionômicas, devido principalmente à ausência do fogo. A sua ausência tem possibilitado que áreas de cerrado stricto sensu sejam invadidas por espécies arbóreas, levando ao adensamento da vegetação, que por sua vez, reduz a riqueza de espécies não lenhosas, por diminuição da luminosidade. Assim, o presente estudo avaliou as respostas de três espécies não arbóreas típicas do cerrado stricto sensu em condições artificiais de sombreamento, a partir de observações fenológicas da mortalidade e capacidade de rebrota, além da análise de parâmetros fotossintéticos. Após 14 meses de experimento, a taxa de mortalidade foi de 43% para as plantas sombreadas, enquanto que as controles (plantas não sombreadas) tiveram uma mortalidade de 10%. As espécies avaliadas (Hyptis campestris, Cissampelos ovalifolia e Lepidaploa chamissonis), quando sombreadas, apresentaram menor ponto de saturação e de compensação luminoso e menor assimilação de carbono, demonstrando potencial de aclimatação. Contudo, plantas sombreadas estão abaixo do ponto de saturação de luz, o que junto com as rebrotas sucessivas pode ter levado ao exaurimento das suas reservas, comprometendo sua sobrevivência. Desta forma, o adensamento vegetacional pode ser um risco para a preservação de plantas não arbóreas de Cerrado. / Abstract: The Cerrado is considered the second largest Brazilian biome in extension, with wide species diversity and endemism. In the last decades, areas of Cerrado have undergone phytophysiognomic alterations, mainly due to the absence of fire. Its absence has allowed tree species to invade areas of cerrado stricto sensu, leading to the densification of vegetation, which in turn reduces the richness of non-woody species, due to the reduction of luminosity. Thus, the present study evaluated the responses of three non-arboreal species typical of cerrado stricto sensu under artificial shading conditions, based on phenological observations of mortality and resprouting capacity, as well as the analysis of photosynthetic parameters. After 14 months of experiment, the mortality rate was 43% for shaded plants, while the controls (unshaded plants) had a mortality of 10%. The evaluated species (Hyptis campestris, Cissampelos ovalifolia and Lepidaploa chamissonis), when shaded, showed lower saturation point and light compensation point and lower carbon assimilation, showing acclimatization potential. However, shaded plants are below the point of saturation of light, which along with the successive resprouts can have led to the exhaustion of their reserves, compromising their survival. In this way, vegetational densification may be a risk for the preservation of non-arboreal Cerrado plants. / Mestre
14

Efeitos da perda de habitat sobre a comunidade de aves de uma floresta estacional seca do Brasil

Melo, Vanicl?zia de Andrade 31 January 2013 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-04-01T22:28:22Z No. of bitstreams: 1 Disserta??o Vanicl?zia de Andrade Melo.pdf: 1015149 bytes, checksum: f174db068eeaabe1f7c9615543e4f0a6 (MD5) / Made available in DSpace on 2016-04-01T22:28:22Z (GMT). No. of bitstreams: 1 Disserta??o Vanicl?zia de Andrade Melo.pdf: 1015149 bytes, checksum: f174db068eeaabe1f7c9615543e4f0a6 (MD5) Previous issue date: 2013-01-31 / Birds are considered sensitive to human disturbance because they have a close relationship with the environmental conditions. In the caatinga, modification of habitat ocurred by a historical process of environmental deterioration as a result of unsustainable use of natural resources. Due to the extreme climatic conditions of the caatinga, it is expected that a more resilient biota survives in this vegetation under to human interventions than those in more stable environments, such as tropical rainforests. Thus, the present study aimed to investigate the effects of habitat loss on a bird community of caatinga area type seasonal dry forest in the municipality of Candiba, Bahia, Brazil, comparing avifaunas occurring in an area of remnant forest (Area I) with adjacent matrix cleared of area (Area II). Six expeditions were conducted, three in the dry season and three in the rainy season, between November 2011 and July 2012. The method of Mackinnon lists was used for recording auditory and visual species. It was recorded 138 species, 92 in the Area I and 94 in the Area II. Both areas showed a low similarity (38%) between their specific compositions, demonstrating that only a small portion of the bird community in the region occurs in both habitat types, tolerating the different states of preservation. Regarding the trophic structure, insectivorous species predominated in both areas, with emphasis on the occurrence species of more specialized habits in only Area I, indicating that they are intolerant to habitat loss. In Area II, were representative species of bird generalist habits, such as granivorous and omnivorous, they seem to benefit from the replacement of native forests by agricultural lands. Although bird species of high sensitivity and forest dependents represented the minority, such species were directly affected by habitat change, since many of them were not recorded in the cleared matrix. Thus, habitat loss is a process that leads to negative effects on the bird community of seasonal dry forest, especially in species composition, which changes as the forest vegetation is removed. / As aves s?o consideradas sens?veis a perturba??es por apresentarem uma estreita rela??o com as condi??es em que o ambiente se encontra. Na catinga, a modifica??o do habitat tem se dado por um hist?rico processo de deteriora??o ambiental, em decorr?ncia do uso insustent?vel dos seus recursos naturais. Em fun??o das condi??es clim?ticas extremas da caatinga, espera-se que nesta vegeta??o sobrevivam biotas mais resilientes a interven??es humanas do que aquelas de ambientes mais est?veis, como as florestas tropicais ?midas. Deste modo, o presente estudo objetivou investigar os efeitos da perda de h?bitat sobre uma comunidade de aves de ?rea de caatinga do tipo floresta estacional seca, no munic?pio de Candiba, Bahia, Brasil, comparando as avifaunas ocorrentes em uma ?rea de remanescente florestal (?rea I) com a da matriz desmatada adjacente (?rea II). Foram realizadas seis expedi??es, tr?s na esta??o seca e tr?s na chuvosa, entre novembro de 2011 e julho de 2012. O m?todo de listas de Mackinnon foi utilizado para o registro auditivo e visual das esp?cies. Foram listadas 138 esp?cies, sendo 92 na ?rea I e 94 na ?rea II. As duas ?reas apresentaram uma baixa similaridade (38%) entre suas composi??es espec?ficas, demonstrando que apenas uma pequena por??o da comunidade de aves da regi?o em ambos os tipos de habitat, tolerando os distintos estados de conserva??o dos mesmos. Quanto ? estrutura tr?fica, as aves inset?voras predominaram tanto na ?rea I como na ?rea II, com destaque para ocorr?ncia de esp?cies de h?bitos mais especializados somente na ?rea I, indicando que s?o intolerantes ? modifica??o de seu habitat. Na ?rea II, foram representativas as esp?cies de aves h?bitos mais generalistas, como as gran?voras e on?voras, que parecem se beneficiar da substitui??o de florestas nativas por ?reas de cultivo agr?cola. Ainda que as esp?cies de aves de alta sensibilidade e dependentes florestais representaram a minoria, tais esp?cies foram diretamente afetadas pela altera??o do habitat, uma vez que muitas delas n?o foram registradas na matriz desmatada. Deste modo, a modifica??o do habitat se mostra como um processo que acarreta em efeitos negativos sobre a comunidade de aves de caatinga arb?rea, sobretudo na composi??o das esp?cies, que ? alterada ? medida que a vegeta??o florestal ? substitu?da por ?reas agr?colas.
15

Myosin Fiber Type Distribution and Metabolic Characteristics in the Hindlimb Muscles of Sloths (Xenarthra: Pilosa)

Spainhower, Kyle B. 29 August 2018 (has links)
No description available.
16

THE EFFECTS OF PERCH DIAMETER AND INCLINE ON THE HIND LIMB MOVEMENTS OF THE ARBOREAL LIZARD, <i>ANOLIS SAGREI</i>

SPEZZANO JR., LAWRENCE CHARLES 02 September 2003 (has links)
No description available.
17

Arboreal habitat structure affects route choice by rat snakes

Hamilton, Rachel A. 09 November 2009 (has links)
No description available.
18

Contested Landscapes : social-ecological interactions between forestry and reindeer husbandry

Horstkotte, Tim January 2013 (has links)
Throughout northern Fennoscandia, reindeer husbandry is a central part in the cultural heritage of the Sámi people. In its history, Sámi culture and reindeer husbandry have undergone significant adaptations to environmental, social and political challenges. Landscape changes on the winter grazing grounds were mainly driven by resource exploitation, especially by industrialized forestry. Important grazing resources were lost, i.e. terrestrial and arboreal lichens that constitute essential key elements in the herding year. In my thesis, I explore the consequences of these transformations in Swedish boreal forests for reindeer husbandry. The multi-disciplinary approach integrates interview studies, ecological fieldwork and theoretical modeling of forest development. I emphasize the understanding of landscapes as multi-dimensional concepts with ecological, social and economic components. They interact in determining the amount of landscape fragmentation in physical or administrative ways, or in enabling reindeer herders to move between different landscape elements. These elements, e.g. forest stands of different ages, can react differently to winter weather. Thus, they enable reindeer herders to adjust their grazing grounds according to the availability of forage, mediated by snow conditions. However, forestry practices have reduced the abundance of old-growth forests, and therewith the functionality of the landscape. By comparing snow conditions in different forest types, I show that multi-layered canopies can offer a more diverse pattern of snow hardness. However, the interaction between forest characteristics with snow is strongly dependent on weather conditions, e.g. the timing and intensity of warm spells. The prevalence of single-layered forest stands therefore can lead to a reduction in snow variability and potentially restricts the availability of suitable grazing grounds for reindeer. If snow conditions hinder reindeer in foraging on terrestrial lichens, old forests formerly supplied reindeer with arboreal lichens. I show how industrial forestry has reduced the availability of this emergency forage by the reduction of old forests and increased landscape fragmentation and analyze the consequences of different management strategies on future habitat availability for arboreal lichens. By integrating these results into a model of forest management, I offer insights into consequences arising from different priorities that either favor timber production or the development of lichen-rich grazing grounds. In conclusion, I emphasize the importance of landscape diversity, as well as the ability to make use of this diversity, as a source of adaptability of reindeer husbandry to changes in grazing conditions by e.g. winter weather dynamics. A shared future of reindeer husbandry and forestry could be fostered by encouraging the social-ecological co-evolution of multiple use landscapes and the enhancement of the cultural and biological significance of the Swedish boreal forests.
19

The Foraging and Travel Patterns of White-Faced Sakis in Brownsberg Nature Park, Suriname: Preliminary Evidence for Goal-Directed Foraging Behavior

Anzelc, Avis M. 20 July 2009 (has links)
No description available.
20

Pólen, Pólis, Política: encen[ações] de um coletivo de trabalhadores-artistas / Pollen, Polis, Politics: Stagings Of A Collective Artists Workers

Curado, Gustavo Idelbrando 04 October 2012 (has links)
A presente dissertação objetiva investigar, relatar e analisar as ações culturais e artísticas promovidas pelo grupo de teatro Dolores Boca Aberta Mecatrônica De Artes. A pesquisa mostra, por meio do relato pessoal de um dos integrantes do grupo, como o coletivo organiza sua estrutura de funcionamento. Aqui são apontados conceitos estruturantes para a filosofia do grupo, como as ideias de Teatro Mutirão e Trabalhador-Artista, além de um levantamento pedagógico de como se deram a construção e apresentação da terceira encenação do grupo, Sombras Dançam Neste Incêndio - Peça Curta em Dois Atos. Dentro das análises, destaca-se a experiência da construção de um teatro feito de árvores, preparado coletivamente pelos próprios espectadores junto com os atores do grupo, o qual chamamos de Arena Arbórea. A perspectiva do trabalho do grupo Dolores Boca Aberta aponta para questões acerca de organização social, debate político, arte e resistência, agitação e propaganda e discussão de modos de produção. / This thesis aims to investigate, report and analyze the cultural or artistic activities promoted by the Dolores Boca Aberta Mecatrônica de Artes Theater Group. The research shows, through the personal report of one of the members, how the group organizes its own operating structure. Some of the structuring concepts of the group\'s philosophy are described and discussed, as well as the ideas of the Task Force theater artistic-workers and a pedagogical survey of the construction and presentation of the third production of the group, \"Shadows dance within this fire - a short play in two acts\". Within the analysis we highlight the experience of the construction of a theatrical space surrounded by trees and called Arboreal Arena, which is collectively prepared by spectators and by the actors of the group. The perspective of the group\'s work points out to questions about social organization, political debate, art and resistance, agitation and propaganda, and the discussion about the means of production.

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