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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.
31

Influência da composição de substrato do recife na atividade e distribuição de peixes zoobentívoros no arquipélago de Fernando de Noronha, Pernambuco / The influence of substratum composition on the activity and distribution of benthic carnivorous reef fishes of the Fernando de Noronha Archipelago

Krajewski, João Paulo 07 February 2010 (has links)
Orientadores: Fosca Pedini Pereira Leite, Sergio Ricardo Floeter / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-16T19:50:45Z (GMT). No. of bitstreams: 1 Krajewski_JoaoPaulo.pdf: 9575479 bytes, checksum: 263e857c27328008c50d4b577be61438 (MD5) Previous issue date: 2010 / Resumo: Os recifes proporcionam abrigo e alimento para diversas espécies de peixes e, portanto, pode haver uma relação entre a distribuição e comportamento de peixes recifais e a composição de substratos do recife. Fatores físicos, especialmente o hidrodinamismo e profundidade, também parecem ter grande influência sobre a distribuição e comportamento de algumas espécies de peixes recifais. No presente estudo a relação entre a distribuição e atividade de espécies de peixes, especialmente as que se alimentam de invertebrados bentônicos (zoobentivoras), e a composição de substratos do recife, hidrodinamismo e profundidade foi estudada em recifes do arquipélago de Fernando de Noronha, Pernambuco. As principais espécies zoobentivoras de Fernando de Noronha forrageiam principalmente sobre substratos compostos por algas filamentosas verdes e vermelhas e algas pardas cobertas de sedimento, e sua atividade alimentar não é distribuída proporcionalmente à abundância relativa dos diferentes substratos. Ainda, para algumas espécies, o uso de substrato pode variar entre recifes. A dieta principal dos zoobentívoros mais abundantes em Fernando de Noronha são poliquetas e crustáceos. Quatro espécies foram estudadas quanto à variação de sua atividade entre diferentes recifes. Haemulon chrysargyreum, Halichoeres radiatus, e Cephalopholis fulva em geral parecem evitar nadar na coluna d'água quando há maior batimento de ondas. Por outro lado, Thalassoma norohhanum não varia seu comportamento em função do hidrodinamismo. A presença de distúrbio no substrato também pode influenciar o comportamento dos peixes recifais de Fernando de Noronha, uma vez que experimentalmente foi demonstrado que espécies carnívoras oportunistas são atraídas por distúrbios causados no substrato não consolidado. Em geral, o hidrodinamismo é o principal fator que influencia a distribuição e comportamento de peixes recifais em Fernando de Noronha, especialmente os planctívoros e alguns herbívoros. A abundância e biomassa de peixes em geral foi maior em recifes com menor hidrodinamismo, mais fundos (>10m) e maior cobertura de corais. Os peixes zoobentívoros de Fernando de Noronha, porém, aparentam ser generalistas na escolha de substrato de forrageamento e habitat e, portanto, parece não haver relação entre sua abundância e a disponibilidade de seus principais substratos de forrageamento. / Abstract: Reefs provide shelter and food for several fish species and, thus, there may be a correlation between the abundance and behaviour of fishes and the reef bottom composition-Physical factors, such as water movement and depth, may also have a profound impact in species distribuiton and activity on reefs. Here, the possible relationship between the distribution and activity of reef fishes, mainly benthic carnivores, and reef bottom composition, water movement and depth was studied in the Fernando de Noronha Archipelago, off Northeast Brazil. The main benthic carnivorous fishes at the archipelago forage mostly on substrata composed by filamentous and brown algae covered by sediments, and the different types of substrata present on reefs were used disproportionaly to their availability. Some studied species also varied their foraging substratum selection between nearby reefs. The main items in the diet of the benthic carnivorous fishes were polychaetes and crustaceans. We also studied the local variation in the activity of four fish species, and Haemulon chrysargyreum, Halichoeres radiatus, e Cephalopholis fulva tended to avoid swimming in the water column when there was higher water movement. On the other hand, Thalassoma noronhanum did not vary its activity with diferent degres of water movement. We also recorded that the presence of substratum disturbance on soft sediments may alter the activity of opportunistic carnivorous fishes, since they were attracted by disturbance on the bottom caused experimentaly and started to forage in the area where the substratum was disturbed. In general, water movement was the main factor influencing the fish communities in Fernando de Noronha, especially of herbivorous and planktivorous fishes. Abundance and biomass of fishes in general were greater in reefs with less water movement, deeper (>10m) and whith more coral cover. The benthic carnivorous fishes of Fernando de Noronha, however, were mostly versatile in their habitat use and foraging substratum selection and its distribution seem not to be influenced by the avalability of their main foraging substratum. / Tese (doutotrado) - Universida / Ecologia / Doutor em Ecologia
32

Spatio-temporal ecology of the yellow mongoose Cynictis penicillata in the Great Fish River Reserve (Eastern Cape, South Africa)

Mbatyoti, Owen A January 2012 (has links)
Very little is known about the spatio-temporal ecology of the yellow mongoose Cynictis penicillata, despite this small carnivore being widely distributed in the southern African subregion. Until the present study, activity patterns and daily movement distances had only been investigated over a single season, and information on home range sizes was only available from a few populations. Here, I aimed at determining the activity patterns and the space use of yellow mongooses over the different seasons of the year in the Great Fish River Reserve (Eastern Cape, South Africa). In addition, I tested some predictions related to environmental factors (variations in photoperiod, climatic conditions and food availability over the year), as well as life cycle (reproduction) and morphological and physiological characteristics (sexual dimorphism and thermoregulatory aspects associated to the possession of an elongated body). From September 2005 to August 2011, spatio-temporal data were collected through 102 continuous tracking sessions (84 during the day and 18 during the night) of 12 adult individuals (seven males and five females) fitted with motion-sensor radio-collars. Additional data were obtained through semi-continuous tracking sessions and random locations. Yellow mongooses were essentially diurnal and crepuscular. Activity levels averaged 57 percent during the day (n = 11,807 fixes) and only 11 percent at night (n = 3,623 fixes). Yellow mongooses emerged from their burrows on average (± SD) 85 ± 62 min after sunrise (range: –11 to +369 min) and returned 21 ± 84 min before sunset (range: –518 to +225 min). The duration of the daily activity period varied between 12 min and 15 h 36 min, with a mean of 9 h 28 min. Both sexes exhibited some overground activity after sunset, but this was most pronounced in males than in females. Nocturnal activity outside the activity period was generally restricted to short underground bouts of activity occurring at anytime of the night. Diurnal resting, with up to 11 bouts per activity period, occurred in 98.8 percent of activity periods. Overall, yellow mongooses were active during 68 ± 17 percent of the time spent outside the burrow. Photoperiod acted as a zeitgeber and activity was negatively affected by adverse climatic conditions (very hot or conversely low temperatures, rain, wet soil) and probably low terrestrial arthropod activity/availability. No intersexual difference in activity levels was found, although the higher body mass of males (on average 16 oercent) implies higher metabolic demands. The total home range size (MCP 100 percent ) averaged 0.55 ± 0.65 km2 (range: 0.10–2.36 km2) and the related total perimeter measured on average 2.80 ± 1.71 km (range: 1.17–7.36 km). Male home ranges were on average more than twice large than those of females, but this difference did not reach statistical significance. However, males had larger daily home ranges (0.13 ± 0.15 km2) than females (0.05 ± 0.05 km2). In addition, daily movement distances of males were longer (1.99 ± 1.07 km) than those of females (1.29 ± 0.66 km). Males also travelled at a faster speed (0.29 ± 0.13 km/h) than females (0.18 ± 0.07 km/h). Overall, sex clearly appeared to play a role in the spatial ecology of yellow mongooses, but the underlying explanation does not seem to be linked to sexual dimorphism (body mass) or reproductive activity. Whilst the role of food availability on the space use of yellow mongooses is unclear, it is likely that low temperatures negatively affect yellow mongoose movements, as they do for their activity levels.
33

Nutrient Availability Affects Flowering Rate but has Limited Influence on Morphology of the Hooded Pitcher Plant, Sarracenia minor.

Lemmons, Justin M. 01 January 2013 (has links)
Carnivorous plants perform as both producers and consumers. Botanical carnivory has evolved in sunny, moist, nutrient-poor environments, and the primary nutrient supplied by prey is proposed to be nitrogen. There is a trade-off between carnivorous and photosynthetic structures which corresponds to degree of carnivory expression and available nutrients. This study was conducted on the hooded pitcher plant, Sarracenia minor, which is a facultative wetland plant and Florida-threatened species. Sarracenia minor is considered a specialist myrmecophage and ants characterize the majority of attracted and captured prey. Ants not only provide nutritional benefit, but also protection against herbivory. A natural population of S. minor in northeast Florida was selected to test response to prey and fertilizer nitrogen in a press-experimental design. Introduced fire ants (Solenopsis invicta) and ammonium nitrate (NH4NO3) were used as prey and fertilizer nitrogen sources, respectively. Treatments included: 1) ant addition; 2) fertilizer addition; 3) ant addition/fertilizer addition; 4) no ants/no fertilizer; 5) control. Treatments were administered biweekly and morphological characteristics and herbivory were measured monthly from April-November 2012. Results indicated no significant treatment effects on plant performance and morphological characteristics, except for a significantly greater number of flowers displayed by the nutrient-deprived group (p < .005). Herbivory by Exyra semicrocea also showed a marginally significant negative effect on the tallest pitchers per ramet. Since nitrogen is primarily stored by pitchers and allocated to new growth in the following growing season, the predictive power of this study may be limited. However, increased flowering rate in the nutrient-deprived group suggests that plants were induced to flower from nutrient stress. Also, a burn at the beginning of the study likely influenced nutrient availability and plant response to experimental treatments. In conclusion, stress may have occurred from both fire and nutrients, and S. minor showed resistance and poor response to nitrogen addition.
34

Diversidade e estrutura da comunidade bacteriana associada às armadilhas da planta carnívora Utricularia gibba (Lentibulariaceae) e ao ambiente aquático. / Diversity and structure of bacterial communities associated to the traps of the carnivorous plant Utricularia gibba (Lentibulariaceae) and aquatic environment.

Almir José Ferreira 16 December 2011 (has links)
A diversidade microbiana em ambientes aquáticos e sua associação com plantas carnívoras ainda é pouco estudada. Assim, a comunidade bacteriana da planta carnívora Utricularia gibba e do seu meio aquático foi avaliada por meio do seqüenciamento em larga escala (454 Roche) de uma biblioteca do gene 16S rRNA. Os resultados indicaram que a comunidade bacteriana na água é significativamente diferente da comunidade dos utrículos. Além disso, a comunidade bacteriana da água é composta principalmente por membros dos filos Proteobacteria, Actinobacteria, Firmicutes e Verrucomicrobia, enquanto que a comunidade presente me U. gibba é composta por membros dos filos Proteobacteria, Firmicutes, Cyanobacteria e Acidobacteria. O gênero Polynucleobacter foi dominante nos dois ambientes aquáticos, mas não foi detectado no interior dos utrículos, onde Acidobacterium e Methylococcus foram os gêneros dominantes. Assim, uma comunidade bacteriana específica no interior dos utrículos deve ter sido selecionada a partir do ambiente, podendo esta atuar na degradação das presas. / The microbial diversity of aquatic environments and their association to carnivorous plants is still poor studied. Thus, the bacterial community associated to traps of Utricularia gibba and its aquatic environment was evaluated by large-scale sequencing (454 Roche) of 16S rRNA library from these environments. The results indicated the bacterial community in water is significantly different from the community of utricles. In addition, the bacterial community detected in water environment is mainly composed by Proteobacteria, Actinobacteria, Firmicutes and Verrucomicrobia, while in utricules of U. gibba the community is composed by Proteobacteria, Firmicutes, Cyanobacteria and Acidobacteria. The genus Polynucleobacter was dominant in water, but was not detected in association with the plant. Inside the plant, the genus Acidobacterium and Methylococcus were dominant, but were not detected in water samples. Thus, a specific bacterial community within the utricles should have been selected from the environment, and could play a role in prey degradation.
35

Production de protéines recombinantes par des plantes carnivores génétiquement transformées : application à Drosera rotundifolia et transfert de la technologie à Nepenthes alata / Production of recombinant proteins by genetically modified carnivorous plants : application to Drosera rotundifolia and technology transfer to Nepenthes alata

Biteau, Flore 14 May 2009 (has links)
Le travail présenté porte sur le développement d’une nouvelle technologie innovante, nommée PAT Friday®, visant à produire des protéines recombinantes au sein des sécrétions extracellulaires de plantes carnivores génétiquement modifiées. Deux objectifs ont été fixés : Réaliser la preuve de concept de la technologie sur le modèle expérimental Drosera rotundifolia, en transformant la plante avec des gènes marqueurs et humains afin de mettre en évidence la présence des protéines recombinantes dans la glu ; et développer, après évaluation, la technologie sur un modèle potentiellement industrialisable, Nepenthes alata. Les résultats ont indiqué la présence des deux protéines marqueurs GFP et GUS dans les tissus et dans la glu de Drosera rotundifolia transformées. Les plantes ont également été transformées génétiquement avec les gènes humains de l’interféron gamma et du facteur intrinsèque. Les protéines recombinantes humaines ont été mises en évidence au sein des tissus végétaux. Le potentiel industriel du modèle Nepenthes alata a ensuite été étudié : 10 à 15 kg de protéines totales par hectare et par an peuvent être produits, grâce notamment à des récoltes successives non destructrices, et la possibilité de contrôler l’activité des protéases digestives naturelles. L’élaboration d’un protocole de régénération de la plante a été entreprise par embryogénèse somatique et organogénèse indirecte, en vue de sa transformation génétique. La technologie PAT Friday®, avec des étapes simplifiées d’extraction et de purification des protéines d’intérêt produites dans le liquide digestif, offre de nouvelles perspectives dans le domaine des protéines thérapeutiques produites à partir de plantes / The present work focuses on the development of a new innovating technology, called PAT Friday®, aiming at producing recombinant proteins into the extra-foliar fluid of modified carnivorous plants. Two objectives were assigned to this work : 1- to realize a proof of concept of the technology on the experimental model Drosera rotundifolia, transformed with marker and human genes, to confirm the occurence of the recombinant proteins into glu ; and 2 - to evaluate and develop, the technology on the model Nepenthes alata, more adapted to industrial scaling-up. The results indicate the presence of two marker proteins GUS and GFP inside the tissues and into the glu of modified Drosera rotundifolia plants. The same plant species has also been transformed with human gamma interferon and intrinsic factor genes. The corresponding human recombinant proteins have been detected into the plant tissues. Potential industrial scaling-up has been studied with the species Nepenthes alata. The results show a potential productivity of 10 to 15 kg of total proteins per hectare per year, thanks to non-destructive repeated harvests, and possibility to efficiently control the natural proteinase activity. The elaboration of a regeneration protocol has been undertaken through indirect organogenesis and somatic embryogenesis, with a view to transform genetically this plant. PAT Friday® technology, with simplified extraction and purification methods of the proteins of interest targeted into the liquid secretions, opens new perspectives in the field of therapeutical proteins produced in plants
36

Plant Carnivory and the Evolution of Novelty in <i>Sarracenia alata</i>

Wheeler, Gregory Lawrence 07 November 2018 (has links)
No description available.

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