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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

Utilização de recursos tróficos por espécies neotropicais de Drosophilidae (Diptera)

Gottschalk, Marco Silva January 2008 (has links)
O estudo da interação entre os indivíduos de uma mesma espécie ou de espécies diferentes é essencial para o entendimento das dinâmicas envolvidas na manutenção das comunidades ou assembléias na natureza. Assim, o estudo das preferências alimentares das larvas dos drosofilídeos, refletidas no padrão de emergência das mesmas dos sítios de oviposição, é de suma importância, uma vez que este grupo de organismos tornou-se um excelente modelo para o estudo de padrões ecológicos. Assim, esta tese busca identificar como as larvas de espécies de Drosophilidae se relacionam na utilização dos recursos tróficos, identificando quais os principais fatores que podem estar atuando na manutenção da diversidade de espécies de suas assembléias em áreas de Mata Atlântica e urbanas de Florianópolis (SC). Realizamos coletas de frutos em onze localidades do Estado de Santa Catarina, onde montamos uma listagem das espécies vegetais hospedeiras utilizadas como sítio de oviposição e das espécies de Drosophilidae que as utilizam. Observamos que as espécies de Drosophilidae colonizam os ambientes urbanos estudados, mas há uma perda de diversidade de espécies, evidenciada pela ausência de espécies raras nestas amostras. Ainda, as espécies de Drosophilidae coletadas apresentaram um caráter generalista quanto à utilização dos recursos tróficos, onde, nas assembléias de Mata Atlântica, verificou-se a formação de grupos ecológicos funcionais. Este tipo de organização não foi observado nas assembléias urbanas, onde há uma grande sobreposição dos nichos e uma menor diversidade de espécies. Além dos frutos, foram coletados também corpos de frutificação de fungos a fim de verificarmos as espécies de Drosophilidae emergentes dos mesmos. Dentre as espécies de moscas emergentes estão as dos gêneros Drosophila, Hirtodrosophila, Mycodrosophila e Leucophenga. Cabe ressaltar que as espécies neotropicais da radiação immigrans-tripunctata (gênero Drosophila) possuem a capacidade de colonizar fungos em ambientes preservados e alterados do bioma Mata Atlântica. Em outro estudo, buscamos verificar como a limitação de recursos alimentares para as larvas de drosofilídes pode influenciar a interação competitiva entre as mesmas. Para tal, foram coletados frutos de Buchenavia tomentosa (Combretaceae) e submetidos a dois tratamentos, um deles com uma suplementação alimentar. Assim, obtivemos evidências de que há restrições alimentares ou nutricionais em recursos naturais, que aumentam a interação competitiva entre espécies da família Drosophilidae. Entretanto, estas espécies possuem diferentes respostas à esta limitação, e o aumento da competição interespecífica parece ser maior que da intraespecífica. Finalmente, foi realizada uma revisão da ocorrência das espécies de Drosophilidae no Brasil, onde foram levantadas 304 espécies coletadas em nosso território. A maioria dos registros é de espécies do gênero Drosophila, o mais bem estudado da família. Os estados mais bem amostrados até o momento são São Paulo, Rio de Janeiro, Rio Grande do Sul e Santa Catarina, além do Distrito Federal, onde há grupos de pesquisa enfocando a ecologia e taxonomia das espécies de Drosophilidae. Esta revisão auxiliou na avaliação dos objetivos anteriores, contribuindo com um panorama do conhecimento e distribuição desta moscas no Brasil. / The study of the interaction among the individuals of a same species or of different ones is essential for the understanding of the dynamics involved in the communities or assemblies maintenance in nature. Thus, the study of the alimentary preferences of the drosophilids larvae, evidenciated by their emergency pattern of the breeding sites, is of highest importance once that this group of organisms became an excellent model for the study of ecological patterns. So, this thesis aimed to identify how the larvae of the Drosophilidae species use the trophic resources, identifying the main factors that can be acting in the maintenancement of the species diversity of assemblies in areas of Atlantic Rain Forest and urbanized of Florianópolis (SC). We collected fruits in eleven locations of the State of Santa Catarina, and we listed the vegetable host species used as breeding sites and the Drosophilidae species emerged of them. We observed that the Drosophilidae species colonize the studied urban environments, but there is a loss of species diversity, evidenced by the absence of rare species in these samples. Although, the collected Drosophilidae species presented a generalist character for the use of the trophic resources, where, the formation of functional ecological groups was verified in the assemblies of Atlantic Rain Forest. This kind of organization was not observed in the urban assemblies, where there are a high niche overlap and lower species diversity. Besides fruits collections, were carried out collections of fungi bodies of fructification in order to verify their emerging Drosophilidae species. Among the emerging fly species are the ones of the Drosophila, Hirtodrosophila, Mycodrosophila and Leucophenga genera. It to be useful to emphasize that the Neotropical species of the immigrans-tripunctata radiation (Drosophila genus) have capacity to colonize mushrooms in preserved Atlantic Rain Forest and antropic environments. In another study, we search for how the limitation in trophic resources for drosophilid larvae could influence the competitive interaction among them. For such, fruits of Buchenavia tomentosa (Combretaceae) were collected and submitted to two treatments, one of them with an alimentary supply. Thereby, we obtained evidences that there are alimentary or nutritional restrictions in natural resources, which increase the competitive interaction among species of the family Drosophilidae. However, these species have different answers to this limitation, and the increase of the interspecific competition seems to be larger than of the intraspecific. Finally, a revision of the occurrence of the Drosophilidae species in Brazil was accomplished, where were found 304 species recorded in our territory. Most of the records is of species of the Drosophila genus, the best studied of the family. The better evalueted states until the moment are São Paulo, Rio de Janeiro, Rio Grande do Sul and Santa Catarina, besides Distrito Federal, where there are research groups focusing the ecology and taxonomy of the Drosophilidae species. This revision helped us in the evaluation of the previous objectives, contributing with a panorama of the knowledge and distribution of these flies in Brazil.
12

Systematics of the Forcipomyiinae (Diptera: Ceratopogonidae) with ecology of certain Quebec forms.

Chan, Kai-Lok. January 1965 (has links)
Most people know the ceratopogonid midges as "no-see-ums" and "sandflies" and have encountered them while on a fishing trip or on a holiday to the seaside, countryside or to mountain regions. The annoyance they give from their bites invariably engenders an abrupt fall in morale and produces an instant strong desire to be elsewhere. As Kettle (1962) has put it, "one midge is an entomological curiosity, a thousand ean be hell!" The term "sandfly" is inappropriate for these insects as it leads to a confusion of the group with the true sandfly Phlebotomus (Psyohodidae) and certain blackflies (Simuliidae). [...]
13

The influence of light on diapause in Euxesta notata (Wiedemann). The dependence of diapause response on bands of visible radiation and on bands of infrared radiation used to extend the photoperiod.

Griswold, Alexander Grant. January 1971 (has links)
No description available.
14

A contribution to the biology of Simulium (Diptera)

Wu, Yi-fang, January 1900 (has links)
Thesis (Ph. D.)--University of Michigan, 1928. / Cover title. "Reprinted from Papers of the Michigan Academy of Science, Arts and Letters, vol. XIII, 1930. Published 1931." "Literature cited": p. 597-599.
15

The biology and taxonomy of Wisconsin black flies (Diptera: Simuliidae)

Anderson, John Richard, January 1960 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 143-150).
16

The ecology, life-histories and systematics of the Tendipedid (Chironomid) midges of the vicinity of Madison, Wisconsin

Cooke, Herman Glenn, January 1962 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 84-85).
17

Biology of Hippelates eye gnats (Diptera: Chloropidae) in Wisconsin

Al-Mulla-Hummadi, Mustafa K. January 1962 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1962. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 117-122).
18

The biology and taxonomy of Wisconsin Tabanidae

Roberts, Richard Harris, January 1956 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Abstracted in Dissertation abstracts, v. 16 (1956) no. 10, p. 1970. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 179-182).
19

Chaoborus flavicans (Meigen) (Diptera, Chaoboridae) : an autecological study /

Parma, Sikke. January 1971 (has links)
Thesis--Groningen. / Includes bibliographical references (p. 125-128).
20

Contributions to the autecology and ecosystematics of immature ceratopogonidae (Diptera), with emphasis on the tribes heteromyiini and sphaeromiini in the middle atlantic United States /

Knausenberger, Walter Ingolf, January 1986 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1986. / Vita. Abstract. Includes bibliographical references (leaves 508-545). Also available via the Internet.

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