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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.
1

Ecologia de Phyllomedusa tetraploidea Pombal & Haddad, 1992 e individualização por marcas naturais

Nascimento, Bruno Tayar Marinho do January 2019 (has links)
Orientador: Reginaldo José Donatelli / Resumo: Ecologia e história natural de Phyllomedusa tetraploidea (Anura: Phyllomedusidae), no interior do Estado de São Paulo, Sudeste do Brasil. Phyllomedusa tetraploidea é uma espécie arborícola típica de mata. Foi estudada durante quatro estações reprodutivas em poça temporária no interior do estado de São Paulo. Dados sobre distribuição horizontal, vertical, substrato, distância do corpo d’agua, morfometria, e desovas foram tomados. O padrão reprodutivo em escala temporal é prolongado estando associado ao aumento de temperatura durante a estação chuvosa. Houve dimorfismo sexual sendo as fêmeas maiores e mais pesadas. No uso do habitat a espécie teve preferência por vegetação arbórea, a uma altura média de 2,26 que variou de 0 a mais de5 metros sendo 45,9% dos registros a 1,1 a 2 metros. Dos indivíduos foram registrados empoleirados 36,6% (n = 95) estavam sobre o interior da poça. Seis tipos de poleiros foram utilizados sendo que 57,2% dos registros feitos em substrato arbóreo. Houve preferencia por cobertura vegetal densa. Oito ninhos foram registrados estando dispostos a uma altura média de 2,6 metros sendo a maioria confeccionado em folhas de árvores. Comportamento territorialista entre machos e eventos de predação de adultos foram observados. / Abstract: Ecology and natural history of Phyllomedusa tetraploidea (Anura: Phyllomedusidae), in the interior of the State of São Paulo, Southeastern Brazil. Phyllomedusa tetraploidea is a typical arboreal species of forest. It was studied during four breeding seasons in a temporary pond in the interior of the state of São Paulo. Data on horizontal distribution, vertical distribution, substrate, water body distance, morphometry, and spawning were taken. The reproductive pattern in time scale is prolonged being associated to the increase of temperature during the rainy season. There was sexual dimorphism with females being larger and heavier. In the habitat use the species had a preference for tree vegetation, at an average height of 2.26 m that ranged from 0 to more than 5 meters, with 45.9% of the logs being 1.1 to 2 meters. Of the individuals were recorded perched 36.6% (n = 95) were on the inside of the pond. Six types of perches were used, being 57.2% of records made on tree substrate. There was a preference for dense plant cover. Eight nests were recorded being arranged at an average height of 2.6 meters and the majority were made from leaves of trees. Territorial behavior among males and events of adult predation were observed. / Mestre
2

Aspectos biogeogrÃficos e autoecolÃgicos de encraves florestais Ãmidos no nordeste do Brasil. / Biogeographics and autoecologics aspects of humid forests enclaves, Northeastern Brazil.

Ivan Jeferson Sampaio Diogo 18 February 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A origem da vegetaÃÃo encontrada nos brejos de altitude nordestinos està associada Ãs variaÃÃes climÃticas ocorridas durante o Pleistoceno, que facilitaram a entrada de espÃcies das florestas AtlÃntica e AmazÃnica no domÃnio semiÃrido. A dispersÃo e a polinizaÃÃo sÃo atuais provas do processo evolutivo que levou ao refÃgio de determinadas espÃcies. O presente trabalho verificou o nÃmero de espÃcies das Florestas AmazÃnica e AtlÃntica, Caatinga e outros Brejos de Altitudes nordestinos presentes na composiÃÃo florÃstica da Serra de BaturitÃ, determinando as sÃndromes de dispersÃo e de polinizaÃÃo da flora do remanescente. O compartilhamento de espÃcies entre os domÃnios indica que houve condiÃÃes ambientais adequadas durante o Pleistoceno tardio para permitir o intercÃmbio entre as floras AmazÃnica e AtlÃntica, gerando ambientes de transiÃÃo ou ecÃtonos nas florestas serranas Ãmidas do Nordeste. Os preditores ambientais zoocoria e carbono orgÃnico do solo juntamente com seus processos ecolÃgicos associados determinam a distribuiÃÃo de espÃcies nos brejos de altitude e consequentemente o nicho ecolÃgico. A Serra de Baturità apresenta a maioria das espÃcies melitÃfilas e dispersas por animais, que diferem entre os componentes lenhoso e nÃo lenhoso da vegetaÃÃo, a altitude e a vertente encontrada. / The origin of vegetation found in the brejos nordestinos is linked to climatic variations that occurred during the Pleistocene, which facilitated the entry of species of Amazonian and Atlantic forests in semiarid areas. The dispersal and pollination are present evidence of the evolutionary process that led to the refuge for certain species. The present study examined the contribution of the number of species of Amazon and Atlantic Forest, Caatinga and Mountain Forests of Northeast to the floristic composition of Baturità mountain range, determining the dispersal and pollinating syndromes. The sharing of species between areas indicates the existence of adequate environmental conditions during the late Pleistocene to allow the exchange between the Amazon and Atlantic floras, creating transition environments or ecotones in moist mountain forests of the Northeast. The environmental predictors zoochory and soil organic carbon along with their associated ecological processes determine the distribution of species in the moist forests and hence the ecological niche. Baturità presents most species melittophilous and dispersed by animals, which differ between woody and non-woody components of vegetation, altitude and slope found.
3

On Small Mammal Sympatry in the Southeastern Amazon and Ecological Relationships with Brazil Nut Dispersal and Harvesting

Solorzano-Filho, Jorge Alberto 03 March 2010 (has links)
The Amazon rainforest harbors the planet's highest biodiversity among terrestrial ecosystems; however, the biology and ecology of most of its species are unknown. Niche partitioning is considered a key factor allowing species co-existence, especially for morphological similar species such as spiny rats of the genus Proechimys. I examined the extent to which habitat differentiation, species body mass, and diet could explain the community composition of small mammals at a site in the southeastern Amazon. Moreover, I radio-tagged sympatric species of Proechimys spp. and Mesomys stimulax (an arboreal spiny rat) to obtain detailed autoecology information, including habitat use and use of space. I found support for niche partitioning among species and associated small mammal species with distinct successional phases of gap dynamics. I also observed among Proechimys spp. a typical polygynous organization: females appeared to be territorial against females of any species of their genus; but male territories overlapped with those of several females. Mesomys stimulax showed evidence of monogamy and possible sociality, although sample sizes were small. To identify the importance of small mammals as seed disperser of Brazil nut seeds, I conduct experiments using a combination of fluorescent powder, seed exclosures, and track plates in forests with and without Brazil nut groves, and in forests with and without Brazil nut harvesting. Among small mammals, only Proechimys spp. removed, dispersed, and preyed upon Brazil nut seeds. Proechimys spp. sometimes scatterhoarded these seeds, and hence have the potential to play a significant role in recruiting new Brazil nut trees. I also trapped small mammals and measured forest structures on the same sites used for the seed dispersal experiment, to determine the ecological effects of Brazil nut harvest on small mammal communities; however, my results showed little evidence of changes associated with the seed exploitation. My results highlight the importance of habitat heterogeneity in structuring small mammal communities, and indicate that forest management practices that alter habitats, such as partial logging, also can be expected to alter small mammal composition and diversity. Proechimys spp. have the potential to play an important role in the ecological restoration of intensive exploited Brazil nut groves.
4

On Small Mammal Sympatry in the Southeastern Amazon and Ecological Relationships with Brazil Nut Dispersal and Harvesting

Solorzano-Filho, Jorge Alberto 03 March 2010 (has links)
The Amazon rainforest harbors the planet's highest biodiversity among terrestrial ecosystems; however, the biology and ecology of most of its species are unknown. Niche partitioning is considered a key factor allowing species co-existence, especially for morphological similar species such as spiny rats of the genus Proechimys. I examined the extent to which habitat differentiation, species body mass, and diet could explain the community composition of small mammals at a site in the southeastern Amazon. Moreover, I radio-tagged sympatric species of Proechimys spp. and Mesomys stimulax (an arboreal spiny rat) to obtain detailed autoecology information, including habitat use and use of space. I found support for niche partitioning among species and associated small mammal species with distinct successional phases of gap dynamics. I also observed among Proechimys spp. a typical polygynous organization: females appeared to be territorial against females of any species of their genus; but male territories overlapped with those of several females. Mesomys stimulax showed evidence of monogamy and possible sociality, although sample sizes were small. To identify the importance of small mammals as seed disperser of Brazil nut seeds, I conduct experiments using a combination of fluorescent powder, seed exclosures, and track plates in forests with and without Brazil nut groves, and in forests with and without Brazil nut harvesting. Among small mammals, only Proechimys spp. removed, dispersed, and preyed upon Brazil nut seeds. Proechimys spp. sometimes scatterhoarded these seeds, and hence have the potential to play a significant role in recruiting new Brazil nut trees. I also trapped small mammals and measured forest structures on the same sites used for the seed dispersal experiment, to determine the ecological effects of Brazil nut harvest on small mammal communities; however, my results showed little evidence of changes associated with the seed exploitation. My results highlight the importance of habitat heterogeneity in structuring small mammal communities, and indicate that forest management practices that alter habitats, such as partial logging, also can be expected to alter small mammal composition and diversity. Proechimys spp. have the potential to play an important role in the ecological restoration of intensive exploited Brazil nut groves.
5

Aspectos biogeográficos e autoecológicos de encraves florestais úmidos no nordeste do Brasil / Biogeographics and autoecologics aspects of humid forests enclaves, Northeastern Brazil

Diogo, Ivan Jeferson Sampaio January 2013 (has links)
DIOGO, Ivan Jeferson Sampaio. Aspectos biogeográficos e autoecológicos de encraves florestais úmidos no nordeste do Brasil. 2013. 87 f. Dissertação (Mestrado em ecologia e recursos naturais)- Universidade Federal do Ceará, Fortaleza-CE, 2013. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-05-20T18:08:23Z No. of bitstreams: 1 2013_dis_ijsdiogo.pdf: 1562015 bytes, checksum: 94a9fdf4c149caf413552b026bc16f4f (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-27T20:34:15Z (GMT) No. of bitstreams: 1 2013_dis_ijsdiogo.pdf: 1562015 bytes, checksum: 94a9fdf4c149caf413552b026bc16f4f (MD5) / Made available in DSpace on 2016-05-27T20:34:15Z (GMT). No. of bitstreams: 1 2013_dis_ijsdiogo.pdf: 1562015 bytes, checksum: 94a9fdf4c149caf413552b026bc16f4f (MD5) Previous issue date: 2013 / The origin of vegetation found in the brejos nordestinos is linked to climatic variations that occurred during the Pleistocene, which facilitated the entry of species of Amazonian and Atlantic forests in semiarid areas. The dispersal and pollination are present evidence of the evolutionary process that led to the refuge for certain species. The present study examined the contribution of the number of species of Amazon and Atlantic Forest, Caatinga and Mountain Forests of Northeast to the floristic composition of Baturité mountain range, determining the dispersal and pollinating syndromes. The sharing of species between areas indicates the existence of adequate environmental conditions during the late Pleistocene to allow the exchange between the Amazon and Atlantic floras, creating transition environments or ecotones in moist mountain forests of the Northeast. The environmental predictors zoochory and soil organic carbon along with their associated ecological processes determine the distribution of species in the moist forests and hence the ecological niche. Baturité presents most species melittophilous and dispersed by animals, which differ between woody and non-woody components of vegetation, altitude and slope found. / A origem da vegetação encontrada nos brejos de altitude nordestinos está associada às variações climáticas ocorridas durante o Pleistoceno, que facilitaram a entrada de espécies das florestas Atlântica e Amazônica no domínio semiárido. A dispersão e a polinização são atuais provas do processo evolutivo que levou ao refúgio de determinadas espécies. O presente trabalho verificou o número de espécies das Florestas Amazônica e Atlântica, Caatinga e outros Brejos de Altitudes nordestinos presentes na composição florística da Serra de Baturité, determinando as síndromes de dispersão e de polinização da flora do remanescente. O compartilhamento de espécies entre os domínios indica que houve condições ambientais adequadas durante o Pleistoceno tardio para permitir o intercâmbio entre as floras Amazônica e Atlântica, gerando ambientes de transição ou ecótonos nas florestas serranas úmidas do Nordeste. Os preditores ambientais zoocoria e carbono orgânico do solo juntamente com seus processos ecológicos associados determinam a distribuição de espécies nos brejos de altitude e consequentemente o nicho ecológico. A Serra de Baturité apresenta a maioria das espécies melitófilas e dispersas por animais, que diferem entre os componentes lenhoso e não lenhoso da vegetação, a altitude e a vertente encontrada.
6

Crescimento de espécies florestais madeiráveis como subsídio para o manejo florestal na Amazônia ocidental / Growth of forest timber species as improvements to the forest management in western Amazon

Cunha, Thiago Augusto da 25 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Reliable growth data from trees are very important in the context of forest management. Tree-characteristics such as architecture and competition are associated with diameter growth. Previous studies analyzing tree growth changes have indicated that these variables can describe these effects more effectively. However, the precise role of these effects in the growth modeling of tropical trees needs to be studied further to discuss more effectively the actual forest management practices. Here, we reconstructed the periodic annual basal area increment (IPAg) of four long-lived timber species from the Amazon forest: Cedro (Cedrela odorata); Cerejeira (Amburana cearensis); Copaíba (Copaifera paupera) e Mogno (Swietenia macrophylla) aiming to explain the IPAg variation by developing a individua-tree growth model using the following potential predictors: tree size, morphometric data, competition; crown position and liana load. The model was fitted using a Gamma distribution in the context of Generalized Linear Models. The statistics criteria and residual distributions showed that growth model was adequate to adjust the observed IPAg data and revealed some dendrometric variables that were involved into the effects that lead the observed variation in IPAg, presenting a broad range of the observed data in situations were growth is complex and variable between species. Trees sampled in good site conditions - expressed as a good crown exposure to light, and therefore low competition - presented higher growth rates than trees sampled under high competition from neighboring trees. Besides, the variables Liana load, for Cedrela, the crown diameter and the Hegyi competition index was demonstrated to be highly influential predictive variable. Also, trees sampled in densities greater than 25 m2.ha-1 had their IPAg% significantly reduced. In the context of basal area increment yield by the space occupied in the forest (crown efficiency) the species presented mostly efficiency when growth in dominant position with thin and long crown (crown formal). Among the species, Cedrela odorata was the most efficient in growth. This behavior reinforces the importance of release trees to obtain better crown exposure. / Dados confiáveis de crescimento de árvores são muito importantes no contexto do manejo florestal. Características próprias da árvore como a arquitetura e a competição estão associadas diretamente com o crescimento em diâmetro e altura. Estudos anteriores indicaram que essas variáveis podem descrever a variação do incremento. No entanto, o efeito dessas variáveis na modelagem do crescimento de árvores tropicais precisa ser mais bem estudado, para discutir efetivamente as praticas de manejo florestal atuais. Portanto, nessa pesquisa reconstruiu-se o incremento periódico anual em área basal (IPAg) de quatro espécies de árvores madeiráveis de vida longa da Amazônia: Cedro (Cedrela odorata); Cerejeira (Amburana cearensis); Copaíba (Copaifera paupera) e Mogno (Swietenia macrophylla) com o objetivo de explicar a variação de IPAg, propondo um modelo de crescimento tipo de árvore individual utilizando os seguintes preditores potenciais: tamanho e morfometria da árvore; o status competitivo; a posição social e a carga de lianas na copa. O modelo foi ajustado considerando a distribuição de probabilidade Gama no contexto de Modelo Linear Generalizado. Em base a critérios estatísticos e avaliação residual, o modelo de crescimento demonstrou ser adequado para explicar a variação de IPAg e revelou variáveis dendrométricas que englobam grande parte dos efeitos que moldaram a variação observada do IPAg, apresentando boa abrangência dos dados observados em situações onde o crescimento é complexo e variado entre as espécies. As árvores quando amostradas em boas condições de sítio, expressado por boa exposição da copa à luz solar e, portanto, pouca competição, apresentaram as maiores taxas de IPAg, no período avaliado, do que aquelas encontradas sob forte competição por árvores vizinhas. Além disso, as variáveis carga de lianas na copa, para Cedrela, o diâmetro de copa e o status competitivo de Hegyi influenciaram de forma significativa o IPAg. Árvores amostradas em densidade maior do que 25 m2.ha-1 mostraram queda significativa do IPAg%. No contexto de incremento em área basal por área ocupada na floresta (eficiência da copa), todas as quatro espécies mostraram-se mais eficientes quando em melhor posição social e quando com copas estreitas e longas (formal de copa pequeno). Entre as espécies a Cedrela odorata foi a mais eficiente no crescimento, comportamento que reforça a importância da liberação das árvores o que proporcionaria melhor exposição da copa à luz solar.
7

Passage, migration behavior, and autoecology of adult Pacific lamprey at Winchester Dam and within the North Umpqua River Basin, Oregon, USA

Lampman, Ralph Tatsuo 22 November 2011 (has links)
The extensive reduction in adult Pacific lamprey (Entosphenus tridentatus) counts at many hydroelectric dams in the northwestern USA signals a substantial decline in lamprey numbers across the entire region in the past 40 to 50 years. Among the many potential causes of this decline, obstruction of migration routes has likely played a substantial role. Within the North Umpqua River basin in southwest Oregon, USA, I focused on the following three research goals: 1) to describe the passage efficiency and migration routes of adult Pacific lamprey at Winchester Dam; 2) to evaluate the seasonal movement patterns of adult Pacific lamprey and their use of holding habitat at Winchester Dam in relation to temperature conditions; and 3) to portray the diversity of upstream migratory behaviors of adult Pacific lamprey and the environmental factors that influence these behaviors. This radio telemetry study was conducted between March 2009 and August 2011 with a combination of fixed stations and manual tracking. Passage efficiency was low in both years (8% and 19%, respectively), and all tagged lamprey that successfully passed the dam used routes other than the fish ladder. Lamprey that migrated early within the run and those with relatively small tags had higher passage rates and traveled further than the other groups of lamprey. Lamprey released above of the dam or those that passed the dam on their own distributed themselves widely in the upstream environment, suggesting that the dam deterred their upstream migration. Using mark-recapture data for the two years, the adult Pacific lamprey population upstream of Winchester Dam was estimated at 960 (95% C.I. [188, 4760]) in 2009 and 556 (95% C.I. [110, 2798]) in 2010, which was considerably lower than historical counts at the dam (between 14,532-46,785 in 1965-1971). Most tagged lamprey that did not pass the dam remained at the base of the dam at the end of the summer migration (63% in 2009 and 67% in 2010). Types of habitat most frequently used by lamprey downstream from the dam included the dam surface (wooden structures with crevices), interface zones between fast and slow water, and highway bridge pilings. The lamprey movement changed considerably between August and September, and the frequency of movements decreased sharply during this period. Tagged lamprey were detected using thermal refuges immediately downstream of the dam that were 0.4 to 2.8 C° colder than the mean river temperature at the dam, and this temperature differential increased as the season progressed. Lamprey may be seeking overwintering habitat associated with hyporheic exchange flows at the dam towards the end of the summer season after their display of heightened activity early in the summer. Ninety-five percent of the overall upstream migration took place during the first spring/summer period, and only small-scale upstream movements were observed during the winter and second spring/summer (4% and 1%, respectively). The rate of upstream migration (median) was the fastest during the initial migration phase and was 1.9 km/day (ranging from 0.3 to 11.0 km/day) for tagged lamprey released above Winchester Dam. During winter, 71% of the lamprey remained in the same location where they initiated holding. Multiple regression analysis indicated that the total upstream distance traveled by individual lamprey was most strongly related to presence/absence of Winchester Dam, relative tag size, and water temperature and photoperiod conditions at release. The presence of Winchester Dam, large relative tag size, and high water temperature / short photoperiod conditions at release significantly reduced upstream migration distance. / Graduation date: 2012

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