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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.
171

Termitofauna (Blattodea: Termitidae) associada a esp?cies arb?reas em ?rea de reserva da Ilha do Catal?o da UFRJ, RJ / Termitofauna (Blattodea:Termitidae) Associated Tree Species in Reserve Area of the UFRJ Catalan Island, RJ

Santos, Aline Barreto 15 December 2015 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-03-13T13:52:35Z No. of bitstreams: 1 2015 - Aline Barreto Santos.pdf: 883584 bytes, checksum: 8c172d2d89cd730277fc41a3b05b4e69 (MD5) / Made available in DSpace on 2017-03-13T13:52:35Z (GMT). No. of bitstreams: 1 2015 - Aline Barreto Santos.pdf: 883584 bytes, checksum: 8c172d2d89cd730277fc41a3b05b4e69 (MD5) Previous issue date: 2015-12-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The arboreal termites that are part of the Brazilian fauna attack urban areas that have expanded into areas of wild vegetation. The urban trees when not follow the proper principles of planting and management, transforms the trees into nesting sites and feeding termites. Thus, arboreal species of termites begin to assume increasing importance as pests. This study aimed to identify the species of termites associated with tree species and verify, under field conditions, if these termites exhibit preference for nesting and foraging, in the sandbank area of Catalan Island, in the municipality of Rio de Janeiro, RJ. For this, 95 were chosen randomly planting rows of trees located in this area. These lines has traveled a path of 100 m, also randomly chosen, and during that route all the trees were inspected to verify the occurrence of termites. Termites found were collected, preserved in 70% alcohol for later identification. To assess the preferred nesting, all the trees were inspected for the presence nests of N. corniger. The occurrence of termites was registered in all tree rows sampled (n = 95). Of the total of 545 inspected trees, 77% were infested by termites, identified four species distributed into two families: three native species Termitidae (Nasutitermes corniger Motschulsky, Nasutitermes jaraguae Holmgren and Microcerotermes strunckii Soerensen) and an exotic species of Rhinotermitidae (Coptotermes gestroi Wasmann). The most frequent species was N. corniger (?2 = 82.04, df = 3, p <0.001), occurring in 79% of infested trees, followed by N. jaraguae (6% of infested trees). The termite species least infested trees were found in C. gestroi (1%) and M. strunckii (1%). In general , the exotic tree species Albizia Lebeck is the most infested by termites and also exotic Leucaena leucocephala is less infested. 114 Nest establishment of N. corniger were identified, and the tree species Schinus terebinthifolius the most nidificada. So the trees of the Catalan's Island salt marsh area are infested with native and exotic termites, however, the native termite N. corniger is predominant. / Os t?rmitas arbor?colas que fazem parte da fauna brasileira atacam ?reas urbanas que expandiram sobre ?reas de vegeta??o silvestre. A arboriza??o urbana quando n?o segue os preceitos adequados de plantio e manejo, transforma as ?rvores em locais de nidifica??o e alimenta??o dos cupins. Dessa forma, esp?cies arbor?colas de cupins passam a assumir import?ncia crescente como pragas. Esse estudo objetivou identificar as esp?cies de cupins associadas a esp?cies arb?reas e verificar, em condi??es de campo, se esses t?rmitas exibem prefer?ncia para nidifica??o e forrageamento, na ?rea de restinga da Ilha do Catal?o, no munic?pio do Rio de Janeiro, RJ. Para isso, foram sorteadas aleatoriamente 95 linhas de plantio de ?rvores localizadas nessa ?rea. Nestas linhas foi percorrido um trajeto de 100 m, tamb?m escolhido aleatoriamente, e durante esse percurso todas as ?rvores foram inspecionadas para verificar a ocorr?ncia de cupins. Os cupins encontrados foram coletados, preservados em ?lcool 70% para posterior identifica??o. Para avaliar a prefer?ncia de nidifica??o, todas as ?rvores foram inspecionadas quanto a presen?a de ninhos de N. corniger. A ocorr?ncia de t?rmitas foi registrada em todas as linhas de plantio amostradas (n=95). Do total de 545 ?rvores inspecionadas, 77% estavam infestadas por cupins, sendo identificadas quatro esp?cies distribu?das em duas fam?lias: tr?s esp?cies nativas de Termitidae (Nasutitermes corniger Motschulsky, Nasutitermes jaraguae Holmgren e Microcerotermes strunckii Soerensen) e uma esp?cie ex?tica de Rhinotermitidae (Coptotermes gestroi Wasmann). A esp?cie mais frequente foi N. corniger (?2 =82,04; g.l.=3; p<0,001), ocorrendo em 79% das ?rvores infestadas, seguida por N. jaraguae (6% das ?rvores infestadas). As esp?cies de t?rmitas menos encontradas nas ?rvores infestadas foram C. gestroi (1%) e M. strunckii (1%). De maneira geral, a esp?cie arb?rea ex?tica Albizia lebeck ? a mais infestada pelos t?rmitas e a tamb?m ex?tica Leucaena leucocephala ? a menos infestada. Foram identificadas 114 nidifica??es de N. corniger, sendo a esp?cie arb?rea Schimus terebinthifolius a mais nidificada. Portanto, as ?rvores da ?rea de restinga da Ilha do Catal?o s?o infestadas por t?rmitas nativos e ex?ticos, no entanto, o t?rmita nativo N. corniger ? predominante
172

História natural de Centris (Paracentris) burgdorfi Friese, 1901 (Apidae, Centridini) / Natural history of Centris (Paracentris) burgdorfi Friese, 1901 (Apidae, Centridini)

Sabino, William de Oliveira 11 July 2017 (has links)
Na presente tese estudei a biologia de Centris (Paracentris) burgdorfi, uma abelha solitária de ampla distribuição no Brasil. O único local de nidificação conhecido até o momento fica em uma área de dunas, no nordeste do Brasil, à 25 km da cidade de Natal. Neste local as fêmeas nidificam exclusivamente em paleodunas à cerca de 1 km do mar. Estudei o sistema de acasalamento da espécie, onde pude constatar que a alta competição por fêmeas próxima ao ninho faz com que o macho tenha que retirar a fêmea do local para conseguir o contato genital. Nenhuma fêmea foi vista acasalando mais de uma vez e, logo após a cópula a fêmea dá início à construção do ninho. O ninho é constituído de um túnel raso com acesso às células de cria, construídas uma ao lado da outra. Avaliei o número de viagens que a fêmea faz para a coleta de óleo e pólen e o tempo despendido em cada ação dentro do ninho (deposição de pólen, óleo, ovoposição e operculação). Durante o período de construção das células as fêmeas não dormem dentro do ninho, e sim, em ramos de Krameria tomentosa, a planta utilizada como fonte de óleo no local. Buscando ampliar nosso conhecimento sobre a espécie, procurei outras populações no Brasil para que pudesse avaliar o nicho trófico. Utilizei o pólen encontrado no corpo das fêmeas para inferir sobre a dieta parcial de adultos e imaturos. Além da área de dunas, no Nordeste, encontramos C. burgdorfi no cerrado em Cavalcante, Goiás e em áreas de campo de altitude, em Ponta Grossa, Paraná. Através da análise polínica, constatei a importância de plantas do gênero Chamaecrista como fonte de pólen, sendo este um dos poucos gêneros compartilhados entre os três locais. Krameria grandiflora foi a fonte de óleo em Cavalcante e em Natal, e Angelonia integérrima, foi a fonte de óleo no Paraná. Isso revela a amplitude de nicho trófico em C. burgdorfi não apenas em relação às espécies de plantas utilizadas na dieta mas, também, quanto ao tipo de elaióforo que a fêmea consegue acessar (epitelial e tricromático). Esta plasticidade possibilita a ampla distribuição da espécie em diferentes fitofisionomias. Analisei nutricionalmente a dieta na provisão da cria de C. burgdorfi do nordeste do Brasil e de células de cria de Centris (Paracentris) pallida, coletadas no sudoeste dos Estados Unidos. Centris pallida é uma espécie de Centridini que perdeu o comportamento da coleta de óleo. Centris burgdorfi possui uma dieta mais rica em lipídeos e proteínas, sendo a dieta de C. pallida mais rica em carboidratos. A dieta mais protéica de C. burgdorfi se deve à presença de Chamaecrista já que plantas que anteras poricidas contem mais proteínas em comparação às não-poricidas, como é o caso das fontes de pólen de C. pallida (Parkinsonia e Olneya) / In the present thesis, I studied the biology of Centris (Paracentris) burgdorfi, a solitary bee of wide distribution in Brazil. The only nesting site known is in a dune area in northeastern Brazil, 25 km from the city of Natal. In this place, the females nest exclusively in petrified dunes about 1 km from the sea. I studied the mating system of the species, where I could verify that the high competition by females near the nest forces the male to carry the female to another place to mate. No female was seen mating more than once and, soon after copulation, the female begins to construct the nest. The nest consists of a shallow tunnel with access to the brood cells. I evaluated the number of trips that the female made to the collection of oil and pollen and the time spent in each action within the nest (depositions of pollen, oil, oviposition and operculation). During the period of construction of the cells the females do not sleep inside the nest, but in branches of Krameria tomentosa, the plant used as source of oil. In order to increase our knowledge about the species, I searched for other populations in Brazil so that I could evaluate the trophic niche. I used pollen found in the body of females to infer about the partial diet of adults and immature. In addition to the dune area in the Northeast, I found C. burgdorfi in the tropical Savanna (Cerrado) in Cavalcante, state of Goiás and in high altitude field areas, in Ponta Grossa, state of Paraná. Through pollen analysis, I verified the importance of plants of the genus Chamaecrista as a source of pollen, being this one of the few genera shared among the three sites. Krameria grandiflora was the source of oil in Cavalcante and in the Natal, and Angelonia integerrima, was the source of oil in the Ponta Grossa. This reveals the trophic niche amplitude in C. burgdorfi not only in relation to the species of plants used in the diet, but also to the type of elaiophore that the female can access (epithelial and trichromatic). This plasticity makes possible the wide distribution of the species in different phytophysiognomies. Nutritionally I analyzed the diet in the provision of C. burgdorfi offspring from northeastern Brazil and from the breeding cells of Centris (Paracentris) pallida collected in the southwestern United States. Centris pallida is a species of Centridini that has lost the behavior of the oil-collection. Centris burgdorfi has a diet richer in lipids and proteins, and the diet of C. pallida is richer in carbohydrates. The most proteinic diet of C. burgdorfi is due to the presence of Chamaecrista, since plants with poricidal anthers contain more proteins compared to non-poricidal ones, such as C. pallida (Parkinsonia and Olneya) pollen sources
173

Processus physiques associés à l'augmentation des précipitations d'été dans le Sud-Est de l'Amérique du Sud dans un scénario de réchauffement climatique

Junquas, Clementine 27 January 2012 (has links) (PDF)
Le Sud-Est de l'Amérique du Sud (SESA) est l'une des rares régions subtropicales où les modèles climatiques du WCRP/CMIP3 projettent une augmentation significative des précipitations en été austral pour la fin du XXIème siècle, dans un scénario de réchauffement climatique. Ce signal est associé à une augmentation de la fréquence des étés identifiés comme des phases positives du mode dominant de la variabilité des précipitations dans la région, ce mode étant défini par des précipitations au-dessus (en-dessous) de la normale dans le SESA (zone de convergence d'Atlantique Sud). Cette tendance est associée à une augmentation de la température de surface de la mer (SST) dans le Pacifique équatorial. Cela est confirmé par des expériences de simulation numérique effectuées avec le système interactif two-way nesting du LMDZ4, qui montrent aussi que l'augmentation projetée des précipitations dans le SESA est associée au signal zonalement asymétrique du réchauffement des SST.
174

Diversity, composition and seasonality of wild bees (Hymenoptera: Apoidea) in a northern mixed-grass prairie preserve

Patenaude, Andrea M. 14 September 2007 (has links)
The objective of this study was to characterize the wild bee fauna of a managed mixed-grass prairie in southwestern Manitoba. Weekly sampling using two methods, sweep-netting and bee bowls, was conducted over two years (2005-2006) at three sites within the Yellow Quill Mixed-grass Prairie Preserve. Spatial and seasonal patterns in diversity indices, taxonomic composition and ecological composition of the bee fauna were identified and investigated in relation to sampling method, environmental conditions, and floral resource availability. A total of 7014 individual bees representing five families and 100 species were collected. Numerically, social nesters from the genera Lasioglossum and Bombus dominated, while mining species of Andrena represented the greatest species richness. Observed spatial and seasonal patterns in the abundance, diversity and composition of the bee community were strongly modified by sampling method, resource limitation in the second year and the presence of the exotic invasive plant leafy spurge (Euphorbia esula). / October 2007
175

Evaluating the Effects of Beach Nourishment on Loggerhead Sea Turtle (Caretta caretta) Nesting In Pinellas County, Florida

Leonard Ozan, Corey R. 01 January 2011 (has links)
The health of Florida's beaches are vital to the survival of loggerhead sea turtles (Caretta caretta), as nearly half of the world's loggerheads nest on the states beaches. Many of the beaches utilized by the turtles have undergone nourishment projects in hopes of combating erosion of the shoreline, protecting beachfront property, and creating more suitable beaches for tourism. Although it is argued that beach nourishment benefits sea turtles by providing more nesting habitat, the effects of the Pinellas County nourishment projects on loggerhead nesting are unknown. Beach nourishment can alter the compaction, moisture content, and temperature of the sand, all of which are variables that can affect nest site selection and the proper development of eggs. This research has four objectives: (1) to create a GIS dataset using historic loggerhead sea turtle data collected at the individual nest level along the West coast of Florida, (2) to examine the densities of loggerhead nests, the densities of false crawls (i.e. unsuccessful nesting attempts), and the nest-to-false crawl ratio on natural and nourished beaches for the 2006-2010 nesting seasons; (3) to determine the effects of beach nourishment projects on the hatchling success rates and emergence success rates; and (4) to determine areas preferred or avoided by turtles for nesting. The study found that nesting and false crawl densities significantly differed between natural and nourished beaches during three of the five nesting seasons. Nesting densities increased directly following nourishment and false crawl densities were higher in nourishment areas during every nesting season. False crawl densities were higher than statistically expected on nourished beaches and lower than expected on natural beaches. No significant differences were found between hatchling and emergence success rates between natural and nourished beaches. However, when the rates were analyzed by nesting season, the average hatching and emergence success rates were always lower on nourished beaches than on natural beaches. A hotspot analysis on nests and false crawls revealed that turtles preferred natural beaches that border nourished areas for nesting while false crawls were more evenly distributed through the study area. Although this study documents the negative effects of beach nourishment on loggerhead sea turtle nesting, nourishment projects are likely to continue because of their benefits to human populations. Further examining of the impacts that humans have on nesting and developing loggerheads will ultimately aid policy formation as we continue to manage and protect the future of the species.
176

Zur Funktion des zellulären Prion-Proteins: eine Verhaltensstudie / The function of the cellular Prion protein: a behavioral study

Greis, Catharina Marlies 21 November 2012 (has links)
No description available.
177

Diversity, composition and seasonality of wild bees (Hymenoptera: Apoidea) in a northern mixed-grass prairie preserve

Patenaude, Andrea M. 14 September 2007 (has links)
The objective of this study was to characterize the wild bee fauna of a managed mixed-grass prairie in southwestern Manitoba. Weekly sampling using two methods, sweep-netting and bee bowls, was conducted over two years (2005-2006) at three sites within the Yellow Quill Mixed-grass Prairie Preserve. Spatial and seasonal patterns in diversity indices, taxonomic composition and ecological composition of the bee fauna were identified and investigated in relation to sampling method, environmental conditions, and floral resource availability. A total of 7014 individual bees representing five families and 100 species were collected. Numerically, social nesters from the genera Lasioglossum and Bombus dominated, while mining species of Andrena represented the greatest species richness. Observed spatial and seasonal patterns in the abundance, diversity and composition of the bee community were strongly modified by sampling method, resource limitation in the second year and the presence of the exotic invasive plant leafy spurge (Euphorbia esula).
178

Diversity, composition and seasonality of wild bees (Hymenoptera: Apoidea) in a northern mixed-grass prairie preserve

Patenaude, Andrea M. 14 September 2007 (has links)
The objective of this study was to characterize the wild bee fauna of a managed mixed-grass prairie in southwestern Manitoba. Weekly sampling using two methods, sweep-netting and bee bowls, was conducted over two years (2005-2006) at three sites within the Yellow Quill Mixed-grass Prairie Preserve. Spatial and seasonal patterns in diversity indices, taxonomic composition and ecological composition of the bee fauna were identified and investigated in relation to sampling method, environmental conditions, and floral resource availability. A total of 7014 individual bees representing five families and 100 species were collected. Numerically, social nesters from the genera Lasioglossum and Bombus dominated, while mining species of Andrena represented the greatest species richness. Observed spatial and seasonal patterns in the abundance, diversity and composition of the bee community were strongly modified by sampling method, resource limitation in the second year and the presence of the exotic invasive plant leafy spurge (Euphorbia esula).
179

Diversity and ecology of arboreal ant communities in a tropical lowland forest / Diversity and ecology of arboreal ant communities in a tropical lowland forest

KLIMEŠ, Petr January 2011 (has links)
The thesis focuses on the study of arboreal ant communities in a highly diverse tropical rainforest in Papua New Guinea. In the first study of its kind, whole patches of forest were sampled extensively for ants foraging and nesting in tree trunks and canopies. An extraordinary amount of material collected from 684 felled trees and 260 bait stations in plots of primary and secondary forest was used to study the mechanisms structuring the diversity and species coexistence of this ecologically important insect group at the local scale. The first chapter addresses the question "Why are ant communities more species rich in primary than in secondary forests?" and explores the main environmental traits that influence their diversity in tropical trees. The second chapter compares the community diversity and composition and nesting preferences of ant species between both forest types. The final third chapter introduces a novel method, involving large-scale manipulation of ant communities that could serve as a template for future studies focused on complex tropical food-webs of canopy arthropods and plants. In summary, the results of the thesis highlight the importance of primary vegetation in conserving the diversity of native ant communities and the relevance of nesting microhabitats and their turnover between trees, rather than tree taxonomic diversity, for sustaining the diverse arboreal fauna in tropical forests.
180

MST e desenvolvimento local : uma experiência do assentamento Conquista na Fronteira / SC

Fiorentin, Marcos January 2006 (has links)
O presente estudo foi elaborado com a finalidade de compreender o processo de desenvolvimento local do Assentamento “Conquista na Fronteira”, bem como a sua contribuição para o Município de Dionísio Cerqueira – SC, onde se encontra localizado. Selecionou-se esta área de estudo, esse assentamento, em função do seu modelo de organização coletivo e também pelas mudanças ocorridas no espaço do Município de Dionísio Cerqueira a partir de sua instalação. Buscou-se, inicialmente, conhecer a organização interna do assentamento, sua forma de organização política, de produção e de consumo; identificar e caracterizar os fatores nucleadores que contribuíram neste processo e apontar as mudanças que aconteceram no espaço do Município. Para atingir tal objetivo, adotou-se uma metodologia qualitativa com levantamento de dados, entrevistas e depoimentos dos Assentados e pessoas do Município de Dionísio Cerqueira. Os resultados mostraram que o período de acampamento foi determinante para os Assentados construírem uma proposta de organização política, de produção e de consumo a partir do coletivo. Quanto aos fatores nucleadores que contribuíram no processo de desenvolvimento local no assentamento, podese citar o Espaço Público, a Educação, a Escola Construindo o Caminho e a questão Cultural. Esta última aponta para uma mudança na forma dos Assentados perceberem e lidarem com as suas memórias: aprendendo a olhar para o passado e assim transformá-lo em algo melhor para viver e (re)organizar o seu território. Na etapa final da pesquisa, identificaram-se as mudanças que aconteceram no espaço do Município de Dionísio Cerqueira-SC após a instalação do assentamento, fazendo um comparativo entre o que existia na área da antiga Fazenda Tracutinga com o que existe atualmente nesta área, ou seja, um assentamento de Reforma Agrária. Os resultados mostraram que o fato de se atribuir uma nova função à antiga fazenda, transformando-a em um assentamento, gerou uma série de mudanças no espaço do município, com o surgimento de novos fixos e fluxos dinamizando, assim, sua economia. Mas houve, principalmente, uma mudança cultural na vida dos seus habitantes que, na fase inicial do assentamento, eram contrários à sua instalação e, hoje, aproximadamente 80% deles são favoráveis e incentivadores de novos projetos de assentamento. A pesquisa mostrou ainda que o assentamento passou a ter influência na vida política e nos demais setores da economia do município, resgatando o chamado poder local. / The present study was elaborated with the purpose to understand the process of local development of the Nesting ““Conquista na Fronteira””, as well as its contribution for the town of Dionísio Cerqueira - SC where if it is located. This nesting was selected as study area because of its collective organization and also for the occurred changes in the space of Dionísio Cerqueira town from its installation. At first it was searched to know the organization of the nesting, the form to organize the politics, production and the internal consumption; to identify and to characterize the centralizer factors nucleadores that had contributed in this process and to point the changes that had happened in the space of the town of Dionísio Cerqueira, from the installation of the nesting. To reach such objective, a qualitative methodology with data-collecting was adopted, interviews with people from the nesting and from the town of Dionísio Cerqueira. The results show that the period of encampment was determinative for the seated ones had constructed to a proposal of organization politics, production and consumption from the collective one. As to the centralizer factors that had contributed in the process of local development in the nesting, it can be quoted the Public Space, the Education, the School “Construindo o Caminho” and the Cultural question. This last one points to a change in the form of the seated ones to perceive and deal with their memories, where the same ones had learned to look at past and then to transform it into something better to live e (to re)organize the territory. In the final stage of the research, it was identified the changes that had happened in the space of the town Dinísio Cerqueira-SC, after the installation of the nesting, making a comparative degree between what existed in the area of the old Tracutinga Farm with what exists currently in this area, or else, after the transformation of the area of the farm in an Agrarian Reformation area. The results had shown that the fact of if attributing to a new function the old farm, transforming it into a nesting, generating a series of changes in the space of the town, with the emergence of new fixtures and flows, improving, this way, the economy of the town. But, especially, there was a cultural change in the life of people from that town, that, at the beginning of the nesting were against its installation and nowadays, approximately more than 80 percent of the people from the town are favorable and encouraging the new projects of nesting. The research still showed that the nesting started to have influence in the politics life of the town, and in the other sectors of the economy of this place, rescuing the called local.

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