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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

Microhabitat Use by the Meadow Vole, Microtus Pennsylvanicus (Ord), on a Reclaimed Grassland

Anderson, Jason J. January 1999 (has links)
No description available.
2

Padrões espaciais e temporais de ocorrência de anuros em riachos de Mata Atlântica e sua detecção por meio de DNA ambiental / Spatial and temporal occurrence of stream frogs in the Atlantic forest and their detection through environmental DNA

Lopes, Thais Sasso 17 June 2016 (has links)
O Brasil apresenta uma das maiores diversidade de espécies de anfíbios, sendo reconhecidas em torno de 500 espécies endêmicas no país, as quais são encontradas predominantemente em área de Mata Atlântica. O monitoramento da herpetofauna e conhecimento da dinâmica espacial e temporal destas espécies são informações básicas, porém, fundamentais ao desenvolvimento de outras áreas de pesquisa e conservação. Neste trabalho reunimos informações sobre ocorrência e abundância de três espécies típicas de riacho, Cycloramphus boraceiensis, Hylodes asper e Hylodes phyllodes e testamos o uso de DNA ambiental para detecção de comunidades de anuros. As amostragens ocorreram em um transecto de 100 a 115 m em quatro riachos no Núcleo de Picinguaba, localizado no Parque Estadual da Serra do Mar, São Paulo, Brasil. Coletas de abundância e uso do habitat ocorreram mensalmente de janeiro de 2007 a dezembro de 2010 e em meses alternados em 2011. Indivíduos pós-metamórficos foram amostrados por procura visual a montante de cada riacho, verificando-se todos os locais ao longo do leito. A localidade de cada indivíduo ativo e inativo foi mapeada e o uso do ambiente foi caracterizado em relação a seis parâmetros ecológicos. As amostras de DNA ambiental foram coletadas em 16 pontos em Abril de 2015. eDNA metabarcoding foi realizado com primer universal de anfíbios para uma região do gene mitocondrial (12S). Registramos um total de 6335 observações visuais. A abundância das três espécies variou entre e ao longo dos riachos, sendo que apenas a espécie Hylodes phyllodes foi registrada no riacho 2. Houve uma sazonalidade na abundância de Cycloramphus boraceiensis e Hylodes asper, sendo ambas espécies encontradas em maior número na estação chuvosa. As três espécies foram encontradas ativas majoritariamente em rochas úmidas ou molhadas, sem musgo e sem cobertura. Indivíduos inativos de Hylodes asper e H. Phyllodes foram encontrados majoritariamente em folhas secas sem musgo e sem cobertura. Por meio da técnica de eDNA metabarcoding, detectamos nove espécies, compatíveis com a amostragem tradicional. O DNA de espécies com fases do ciclo de vida atreladas aos riachos e com maior constância na amostragem tradicional foi detectado em maior proporção. Nossos estudos demonstraram que os resultados da amostragem tradicional e de eDNA metabarcoding fornecem informações fundamentais e complementares, sendo uma combinação de ambas metodologias potencialmente útil a futuros estudos de ecologia / Brazil ranks as the country with one of the highest amphibian species diversity. Streams in the Atlantic forest of southeastern Brazil have an important availability of microenvironments and harbors a particular richness in amphibian species. Monitoring herpetofauna and knowledge on their spatial and temporal dynamics provide primary information for ecological studies, and are essential to the development of other areas such as conservation biology. In this work we gather information on the occurrence and abundance of three torrent frogs, Cycloramphus boraceiensis, Hylodes asper and Hylodes phyllodes and examine the reliability of eDNA analysis to detect anuran communities. Samplings occurred within a 95 to 115 m transect in four streams in Núcleo Picinguaba, at the Parque Estadual da Serra do Mar, São Paulo, Brazil. Individual encounter number and their habitat were monthly recorded from January 2007 to December 2010 and every two months in 2011. We searched for post-metamorphic individuals while walking upstream for 30-60 min, checking all visually accessible spots in the streambed. The location of each active and inactive individual was mapped and its habitat use was characterized in relation to five ecological parameters. We collected eDNA samples at 16 sites on April, 2015. We used eDNA metabarcoding approach with a universal amphibian primer of a mitochondrial marker (12S) to detect amphibian communities. We recorded a total of 6335 visual observations. The three species abundance varied along and between streams and only Hylodes phyllodes were found in the stream 2. Abundance of C. boraceiensis and H. asper was significantly higher in the wet seasons. The three species were found active mainly in wet rocks, without moss and without cover. Inactive individuals of Hylodes asper and H. phyllodes were found mainly in dry leaves, without moss or cover. Through eDNA metabarcoding, we detected nine species, which were consistent with traditional survey results. DNA of riparian species and species with higher constancy in traditional surveys were detected in higher proportions. Our study showed that traditional survey and DNA metabarcoding results can be complementary and both methodologies can be combined in future ecology studies
3

Padrões espaciais e temporais de ocorrência de anuros em riachos de Mata Atlântica e sua detecção por meio de DNA ambiental / Spatial and temporal occurrence of stream frogs in the Atlantic forest and their detection through environmental DNA

Thais Sasso Lopes 17 June 2016 (has links)
O Brasil apresenta uma das maiores diversidade de espécies de anfíbios, sendo reconhecidas em torno de 500 espécies endêmicas no país, as quais são encontradas predominantemente em área de Mata Atlântica. O monitoramento da herpetofauna e conhecimento da dinâmica espacial e temporal destas espécies são informações básicas, porém, fundamentais ao desenvolvimento de outras áreas de pesquisa e conservação. Neste trabalho reunimos informações sobre ocorrência e abundância de três espécies típicas de riacho, Cycloramphus boraceiensis, Hylodes asper e Hylodes phyllodes e testamos o uso de DNA ambiental para detecção de comunidades de anuros. As amostragens ocorreram em um transecto de 100 a 115 m em quatro riachos no Núcleo de Picinguaba, localizado no Parque Estadual da Serra do Mar, São Paulo, Brasil. Coletas de abundância e uso do habitat ocorreram mensalmente de janeiro de 2007 a dezembro de 2010 e em meses alternados em 2011. Indivíduos pós-metamórficos foram amostrados por procura visual a montante de cada riacho, verificando-se todos os locais ao longo do leito. A localidade de cada indivíduo ativo e inativo foi mapeada e o uso do ambiente foi caracterizado em relação a seis parâmetros ecológicos. As amostras de DNA ambiental foram coletadas em 16 pontos em Abril de 2015. eDNA metabarcoding foi realizado com primer universal de anfíbios para uma região do gene mitocondrial (12S). Registramos um total de 6335 observações visuais. A abundância das três espécies variou entre e ao longo dos riachos, sendo que apenas a espécie Hylodes phyllodes foi registrada no riacho 2. Houve uma sazonalidade na abundância de Cycloramphus boraceiensis e Hylodes asper, sendo ambas espécies encontradas em maior número na estação chuvosa. As três espécies foram encontradas ativas majoritariamente em rochas úmidas ou molhadas, sem musgo e sem cobertura. Indivíduos inativos de Hylodes asper e H. Phyllodes foram encontrados majoritariamente em folhas secas sem musgo e sem cobertura. Por meio da técnica de eDNA metabarcoding, detectamos nove espécies, compatíveis com a amostragem tradicional. O DNA de espécies com fases do ciclo de vida atreladas aos riachos e com maior constância na amostragem tradicional foi detectado em maior proporção. Nossos estudos demonstraram que os resultados da amostragem tradicional e de eDNA metabarcoding fornecem informações fundamentais e complementares, sendo uma combinação de ambas metodologias potencialmente útil a futuros estudos de ecologia / Brazil ranks as the country with one of the highest amphibian species diversity. Streams in the Atlantic forest of southeastern Brazil have an important availability of microenvironments and harbors a particular richness in amphibian species. Monitoring herpetofauna and knowledge on their spatial and temporal dynamics provide primary information for ecological studies, and are essential to the development of other areas such as conservation biology. In this work we gather information on the occurrence and abundance of three torrent frogs, Cycloramphus boraceiensis, Hylodes asper and Hylodes phyllodes and examine the reliability of eDNA analysis to detect anuran communities. Samplings occurred within a 95 to 115 m transect in four streams in Núcleo Picinguaba, at the Parque Estadual da Serra do Mar, São Paulo, Brazil. Individual encounter number and their habitat were monthly recorded from January 2007 to December 2010 and every two months in 2011. We searched for post-metamorphic individuals while walking upstream for 30-60 min, checking all visually accessible spots in the streambed. The location of each active and inactive individual was mapped and its habitat use was characterized in relation to five ecological parameters. We collected eDNA samples at 16 sites on April, 2015. We used eDNA metabarcoding approach with a universal amphibian primer of a mitochondrial marker (12S) to detect amphibian communities. We recorded a total of 6335 visual observations. The three species abundance varied along and between streams and only Hylodes phyllodes were found in the stream 2. Abundance of C. boraceiensis and H. asper was significantly higher in the wet seasons. The three species were found active mainly in wet rocks, without moss and without cover. Inactive individuals of Hylodes asper and H. phyllodes were found mainly in dry leaves, without moss or cover. Through eDNA metabarcoding, we detected nine species, which were consistent with traditional survey results. DNA of riparian species and species with higher constancy in traditional surveys were detected in higher proportions. Our study showed that traditional survey and DNA metabarcoding results can be complementary and both methodologies can be combined in future ecology studies
4

Microhabitat Use by Translocated Wild Turkeys in the Mississippi Delta

McKinney, Matthew Ryan 11 May 2013 (has links)
Eastern wild turkeys (Meleagris gallapavo silvestris) were extirpated from most of the Mississippi Alluvial Valley (MAV) by 1980 by overharvest and habitat loss. Federal programs have restored areas of the MAV to hardwood forest, potentially warranting restoring wild turkeys to the MAV. As part of a pilot restoration study, I gathered data on resource use and nest sites from July 2010–August 2011. I observed intraspecific niche specialization and spatial niche separation between genders. Spatiotemporal variation in resource availability and intraspecific competition appear to be factors influencing intraspecific niche specialization. Mature hardwood forest was primary habitat selected by translocated wild turkeys. Hardwood regeneration areas were primary habitat selected by hens for nesting. Visual obstruction from 0.0 m–0.5 m was important in selecting fine-scale nest sites. Hardwood regeneration areas have dual value for restoring wild turkeys to the MAV: future mature hardwood areas; and potential nest sites.
5

Mangrove Shoreline Fish Assemblages of Oleta River State Park: Baseline Conditions in an Urban System

De Angelo, Jacquelyn Alexis 01 January 2010 (has links)
Oleta River State Park (ORSP), located in North Miami-Dade County is known as the most highly urbanized State Park in all of Florida. The present study was conducted as part of an ongoing seasonally-resolved survey of fish utilization of the mangrove shorelines of Biscayne Bay. Previous Unit Management Plans published by the Division of Recreation and Parks have lacked information concerning the park?s prominent mangrove forests along with its icthyofauna. The main purpose of this thesis was to provide a baseline characterization of the mangrove-fish assemblages and microhabitat trends of ORSP, against which future changes in and around the Park can be gauged. Fish assemblages inhabiting the mangrove shorelines were examined using a visual ?belt-transect? census method over 11 consecutive seasons. Microhabitat variables including salinity, water temperature, water depth, water clarity and distance from Baker?s Haulover Inlet were examined for possible correlations with fish metrics. Several significant differences were evident in the taxonomic richness (number of taxa per unit area) and densities of the five most abundant taxa within the shoreline habitats in terms of seasonal variation and microhabitat variable distribution along the river. Taxonomic richness was typically greater in survey sites located closer to Baker?s Haulover Inlet. Oleta River?s mangrove shoreline fish assemblages appear to reflect (1) proximity of the mangroves that they occupy to Baker?s Haulover Inlet; (2) temperature regime along the shoreline; and (3) the salinity gradient found within the river. Fish assemblage and microhabitat information collected here could serve as a ?baseline? in future investigations of the effects of further urbanization or the effects of other anthropogenic changes to Oleta River and its mangrove habitat, including possible changes to freshwater flow associated with the Comprehensive Everglades Restoration Plan.
6

Effect of Nest Structure on Microclimate and Hatching Success of Roseate Tern (Sterna dougallii) on the Islands of Penghu, Taiwan

Sung, Hsin-Yi 11 February 2009 (has links)
Appropriate microclimates are essential for the development of embryos in avian eggs. Physical demands of incubating adults would also be affected by microclimate. The breeding areas of the Roseate Tern (Sterna dougallii) overlap with intense solar radiation and the presence of tropical cyclone and they prefer nest structure with vegetation or rock walls, as these may provide concealment to the surrounding weather. The objectives of this study were to examine the effect of nest structure on the nest microclimate and hatching success. In addition to nest structures, the effect of nest materials and parental incubation behavior on microclimate were also investigated. Results showed that the average temperature of vegetation-removed nests was higher than that of the control group. Rock walls seemed to prevent moisture formed from dew and rain. Incubation behavior can prevent eggs from overheating. However, there were no differences in parental thermal behavior and hatching success between nest types. To sum up, vegetation next to the nest can prevent the eggs from overheating while parents were temporarily absent. Parental incubation can insulate the eggs from surrounding weather stresses, and compensate the negative effect of nest structure with harsh conditions.
7

Mixobiota de floresta atlântica: espécies ocorrentes em Elaeis Guineensis Jacq. (Arecaceae)

Firmino da Silva, Clebson January 2006 (has links)
Made available in DSpace on 2014-06-12T15:53:43Z (GMT). No. of bitstreams: 2 arquivo5238_1.pdf: 459864 bytes, checksum: df7c790bb8a9e7b224fd9cb0a10b359d (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / Realizou-se um estudo sobre as espécies de Myxomycetes que ocorrem em Elaeis guineensis Jacq. (dendezeiro), visando contribuir para o conhecimento sobre os representantes deste grupo que estão associados com palmeiras no Brasil. A incidência, abundância, diversidade taxonômica (espécie/gênero) dos esporocarpos em estipes, folhas, brácteas, inflorescências e frutos (vivos ou mortos) de dendezeiros foi analisada em 20 indivíduos presentes em três fragmentos de Floresta Atlântica da Reserva Ecológica do Gurjaú, Cabo de Santo Agostinho, Pernambuco (08º10 00 e 08º15 00 S; 35º02 30 e 35º05 00 WGr.). Calculou-se a abundância relacionando-se o número de espécimes do táxon e o total de espécimes obtidos, e enquadrou-se cada espécie como rara (0,5-1%), ocasional (2-4%), comum (5-7%) ou abundante (superior a 7%). Exsicatas foram depositadas no Herbário UFP. As espécies foram listadas em ordem alfabética por subclasse. Apresenta-se a distribuição conhecida para o Brasil para cada espécie e os registros para palmeiras neste país. O dendezeiro mostrou ser um excelente substrato para o desenvolvimento de mixomicetos. Todas as subclasses, cinco das seis ordens e 50% das famílias reconhecidas para este grupo foram registradas. Com este estudo, 22 espécies foram acrescentadas à lista de mixomicetos associados com dendezeiro no Brasil; destas, Ceratiomyxa sphaerosperma, Didymium anellus e Physarum gyrosum não haviam sido referidas como ocorrendo em palmeiras neste país. Nos ambientes estudados, as Physaraceae são as mais freqüentes, seguidas pelas Trichiaceae. Hemitrichia serpula, Arcyria cinerea e Physarum compressum são espécies comumente encontradas em E. guineensis, confirmando sua preferência em se associar com palmeiras. Conclui-se que a mixobiota do dendezeiro é diversificada, ocorrendo à esporulação preferencialmente em órgãos mortos
8

Longitudinal Patterns of Community Structure for Stream Fishes in a Virginia Tailwater

Hunter, Anne Katherine 15 April 2003 (has links)
I examined the abundance, composition, and distribution of 34 fishes within the first 24 km below Philpott Dam on the Smith River, a hydropeaking system in Virginia. Fish were sampled at 12 sites over 8 time periods ranging from 2000 to 2002 across April, June, and October. I evaluated spatial and temporal change in fish community characteristics. Species demonstrated persistent trends in abundance, diversity, and composition throughout the duration of the study. Fish abundance and diversity generally increased with increasing distance from the dam. Fish composition changed minimally across seasons and years, indicating consistent fish assemblages. Distributional patterns suggested a strong response to thermal gradients and presence of tributaries. I concluded that temperature and tributary location directly influence fish community patterns in the Smith River and that the patterns are persistent over space and time. I characterized spawning microhabitat use and availability, and tested transferability of spawning microhabitat criteria for Etheostoma flabellare and Nocomis leptocephalus, two of the most common species in the Smith River. E. flabellare preferentially selected small and large cobble size rocks for their spawning rock. N. leptocephalus selected areas with slower demersal and mean water column velocities in which to build their mounds. Transferability tests were conducted using spawning microhabitat criteria from the unregulated Roanoke River (Smith 1999). The logistic regression model developed for E. flabellare by Smith (1999), using information on the diameter of the spawning rock, silt, and embeddedness, transferred with most success with over half of the spawning sites and available sites correctly classified in the Smith River. / Master of Science
9

Bottlenecks and Microhabitat Preference in Invasive Wall Lizard, Podarcis muralis

Homan, Cassandra M. 18 October 2013 (has links)
No description available.
10

Head-start Juvenile and Adult Resident Eastern Box Turtles (Terrapene carolina carolina): Winter Ecology Including Microhabitat Selection, Temperature Tolerance and Philopatry

Moon, Amberly 01 January 2011 (has links)
The Eastern box turtle (Terrapene carolina carolina) is one of the most common reptiles in North America, but is soon to be threatened due to increased urbanization, disease, and the pet and food trades. In order to assist resource managers in choosing suitable sites for relocation studies, more information on the winter ecology of this species is necessary. We examined the temperature tolerance, microhabitat and degree of philopatry to hibernacula for juvenile and adult E. box turtles for two consecutive winters in Charles City Co, VA. The turtles were tracked via radio telemetry to record point locations during the active and inactive seasons. iButton data loggers were attached to each turtle to record temperature throughout winter. Vegetation data were collected and analyzed to determine if there are microhabitat differences between adult and juvenile turtles, and between occupied and random plots. Philopatry to wintering hibernacula was determined by measurements in the field and using ArcGIS. Adults had significantly higher minimum temperatures than juveniles during the first winter (P=0.027), but not during the second winter (P=0.327). Shrub and canopy cover were marginally higher for random plots than for occupied turtle hibernacula plots (P=0.066 and P=0.092, respectively); however there were no significant differences for any of the vegetation variables between adults and juveniles. Some of the turtles demonstrated site fidelity of their hibernacula. The temperature data from this study suggests that juveniles may have poorer hibernacula selection and therefore lower minimum temperatures compared with adults, but this was not seen in our second season suggesting that juvenile turtles may learn to choose better hibernacula or to dig deeper. The difference in findings for the two winters could be attributed to illness by several of the turtles the first winter, by increased maturity in the juveniles the second winter or by the significant difference in ambient temperature for the two winters (P=0.0001). Juveniles do not differ from adults in microhabitat selection, therefore resource managers may not need to plan differently for juveniles and adults in relocation studies. We also conclude that both age groups of T. c. carolina exhibit site fidelity of hibernacula.

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