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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.
21

The Effects of Changing Spring Temperatures on Fuel Use, Mass Loss, Emergence Time, and Chill Coma Recovery in Solitary Mason Bees (Osmia spp.).

Walinga, Charlotte P. January 2016 (has links)
Repeated cold exposures and warmer winter temperatures might negatively affect insects by depleting stored fuel reserves. I researched the effects of fluctuating thermal regimes on two species of solitary mason bees (Osmia albiventris and O. lignaria) by quantifying mass loss and reserves of lipids, free sugars, and glycogen after experimental temperature treatments during early spring. In a second season, I quantified mass loss, time to emergence, and time to recover from chill coma after bees had been exposed to one of two spring-time temperature regimes. I found that warmer temperatures in combination with greater temperature variability increases mass loss and the depletion of fuel reserves. Additionally, my results suggest that accelerated bee emergence helps to mitigate mass loss. Overall, these bees appear resilient in the face of changing spring temperatures. Résumé: On sait peu sur la façon dont la variabilité environnementale affecte les abeilles solitaires sauvages. Ma recherche a étudié la façon dont les régimes thermiques fluctuants affectent la vigueur de deux espèces d'abeilles solitaires (Osmia albiventris et O. lignaria) en quantifiant la perte de masse ainsi que les réserves métaboliques (lipides, sucres libres, et glycogène) des abeilles suite à des manipulations expérimentales de la température printanière. Dans une deuxième saison, j’ai quantifié la perte de masse, le temps de l'émergence et le temps pour récupérer du coma froid après que les abeilles avaient été exposées à l'un de deux régimes de températures printanières. Mes résultats indiquent que les températures plus chaudes ont tendance à augmenter la perte de masse et des réserves métaboliques lorsqu'elles sont combinées avec une plus grande variabilité. De plus, mes résultats suggèrent que ces abeilles sont résilientes face aux températures printanières changeantes.
22

Influ?ncia do comprimento do ninho-armadilha na sele??o das cavidades para nidifica??o, na mortalidade da prole e na raz?o sexual de abelhas solit?rias (Hymenoptera: Apidae)

Santos, Claudia Oliveira dos 26 March 2013 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-03-01T00:40:16Z No. of bitstreams: 1 DISSERTA??O Claudia.pdf: 581878 bytes, checksum: 64bfb898fa3dfecf415c1fe65fad5fbf (MD5) / Made available in DSpace on 2016-03-01T00:40:16Z (GMT). No. of bitstreams: 1 DISSERTA??O Claudia.pdf: 581878 bytes, checksum: 64bfb898fa3dfecf415c1fe65fad5fbf (MD5) Previous issue date: 2013-03-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aimed to investigate the acceptance of cavities with different lengths for nesting and the cavity size effects on the sex ratio and offspring mortality of solitary bees in two agricultural areas in Feira de Santana, Brazil. The samplings were carried out monthly, during 12 months, using trap-nesting (=NA) length 5, 10, 15 and 20 cm. A total of 124 nests, 591 building cells, and 479 emerging imago were sampled. There was a higher number of nesting in area I (n=86) than in area II (n=38). Centris analis Fabricius 1804, Centris tarsata Smith, 1874, and two Megachile species nested in ?rea I, being C. analis the specie with highest number of established nest (n=72, 83.7%), while other species had low nesting frequency (4%) and a higher bee richness, with six species occupying the trap-nesting. Tetrapedia diversipes Klug, 1810, established highest number of nest (n=29, 76.3%). Species used different NA size in both areas. In the area I, they nesting with higher frequency in NA with 10 cm (38%) and 15 cm (38%), while in the area II, there was cavity occupation with 20 cm (50%). Bees nested in most part of the year, except in months of autumn-winter, between April and August, when the bee nesting frequency was reduced or the activity was suspended. The natural enemies that emerged from the nests were species of Hymenoptera Coelioxoides sp, Mesocheira bicolor Fabricius, 1804, and a species of Chrysididae. The mortality rate by unknown reason in the areas I and II was 21.4% and 13.5% respectively, with higher incidence recorded to Centris analis. There was a higher mortality in smallest nests (5 cm) and there was no difference among the cavities with 10, 15, and 20 cm. / Este trabalho teve como objetivo investigar a utiliza??o de cavidades de diferentes comprimentos para confec??o de ninhos e os efeitos do tamanho da cavidade sobre a raz?o sexual e mortalidade da prole de abelhas solit?rias. O estudo foi conduzido em duas ?reas agr?colas no munic?pio de Feira de Santana, Bahia. Foram realizadas amostragens mensais durante 12 meses, usando ninhos-armadilha (NA) de comprimento 5, 10, 15 e 20 cm. Foram obtidos 124 ninhos, 591 c?lulas de cria constru?das e 479 imagos emergentes. Houve maior n?mero de nidifica??es na ?rea I (n=86) do que na ?rea II (n= 38). Centris analis Fabricius 1804, Centris tarsata Smith, 1874 e duas esp?cies de Megachile nidificaram na ?rea I, sendo C. analis a esp?cie com maior n?mero de ninhos estabelecidos (n=72, 83,7%), enquanto as outras esp?cies tiveram baixa freq??ncia de nidifica??o. A ?rea II apresentou menor freq??ncia de nidifica??o (4%) e maior riqueza de abelhas, com seis esp?cies ocupando os ninhos-armadilha. Tetrapedia diversipes Klug, 1810, estabeleceu maior n?mero de ninhos (n=29, 76,3%). As esp?cies utilizaram diferentemente os tamanhos de NA nas duas ?reas. Na ?rea I, as abelhas nidificaram com maior freq??ncia nos NA de 10 cm (38%) e de 15 cm (38%), enquanto na ?rea II houve maior ocupa??o das cavidades de 20 cm (50%). As abelhas nidificaram na maior parte do ano, com exce??o dos meses de outono-inverno, entre abril e agosto, quando a frequ?ncia de nidifica??o das abelhas foi reduzida ou a atividade foi suspensa. Os inimigos naturais que emergiram dos ninhos inclu?ram esp?cies de abelhas Coelioxoides sp, Mesocheira bicolor Fabricius, 1804 e uma esp?cie de Chrysididae. A taxa de mortalidade por causas desconhecidas nas ?reas I e II foi respectivamente 21,4% e 13,5%, com maior incid?ncia registrada em Centris analis. Houve uma maior mortalidade nos ninhos curtos (5 cm), n?o havendo diferen?a entre as cavidades de 10, 15 e 20 cm.
23

COMUNIDADE DE ABELHAS SOLITÁRIAS (Hymenoptera: Apidae) QUE NIDIFICAM EM NINHOS-ARMADILHA EM UMA ÁREA DE CERRADO NO PARQUE ESTADUAL DO MIRADOR, FORMOSA DA SERRA NEGRA, MARANHÃO / COMMUNITY OF SOLITARY BEES (Hymenoptera: Apidae) NESTING IN TRAP-NESTS IN AN AREA OF CERRADO IN THE PARQUE ESTADUAL DO MIRADOR, FORMOSA DA SERRA NEGRA, MARANHÃO

CARVALHO, Gracy Chrisley Alencar 13 May 2014 (has links)
Made available in DSpace on 2016-08-17T15:00:43Z (GMT). No. of bitstreams: 1 Dissertacao Gracy Chrisley Carvalho.pdf: 2155639 bytes, checksum: fdf1bfc985cd4dc0f7e767ea5d5107a7 (MD5) Previous issue date: 2014-05-13 / FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO / Knowing the diversity of solitary bees through trap-nests have sought to compose a checklist of diversity, as well as the account of the behavior and biology of the species. Few studies have been done in the state of Maranhão, which is a privileged area, as it includes within its boundaries the two major biomes. Given these few reports, the purpose of this work was to study the community of solitary bees by the method of trap nests for two years, in an area of cerrado and gallery forest, in the Parque Estadual do Mirador. Also, describe the nesting biology of Centris (Hemisiella) dichrootricha and analyze the floristic composition of the food of her offspring. The study area is located in the Parque Estadual do Mirador, municipality of Formosa Serra Negra, Maranhão. The method used was the trap-nests in wood diameters 6, 8, 10, 12, 14 and 16 mm, these were grouped in sets of 6 nests, totaling 300 nests per area. A total of 101 nests belonging was founded 11 bee species, including eight species occurred in the Gallery Forest and six in the Cerrado, and the similarity was low among habitats (SJ = 0.27). Two species were dominant in the community, Centris dichrootricha in Gallery Forest and the Centris tarsata in Cerrado. The diversity and evenness of species were higher in gallery forest than in the cerrado. The peak of the nests was founded in November (2012 and 2013) and August (2013), there were nothing correlation between the precipitation (rCE = -0.061; pCE = 0.775 and rMG = 0.194; pMG = 0.365). After 24 months of collecting the species rarefaction curve did not reach the asymptote for both habitats. Centris dichrootricha observed nesting in 29 nests in sizes 8, 10, 12 and 14mm. The species used in most resources from the Cerrado, which consisted both in the sediment to compose the cells and the pollen material and floral oil. Pollen types Byrsonima the genus of the Malpighiaceae family were the most representative in the samples. In this study five species of Centris were collected for a single study, all represented in the gallery forest. Thus, the study reveals the importance of forests as a refuge for some species of solitary bees. The biology of C. dichrootricha showed a preference for nesting in cavities with different sizes and in shady places in the Gallery Forest , also Euglossa amazonica species which hitherto had not been recorded nesting in trap-nests, especially in areas of the field was observed Cerrado. Besides these two species, the present study contributes to the expansion of the geographical distribution and Centris bicornuta e Centris terminata, these species are little studied in Brazil. / Conhecer a diversidade de abelhas solitárias através de ninhos-armadilha tem buscado compor um checklist da diversidade, assim como o relato do comportamento e da biologia das espécies. Poucos foram os estudos já realizados no Estado do Maranhão, que é uma zona privilegiada, pois incluem em seus limites os dois principais biomas brasileiros. Diante desses poucos relatos, o propósito desse trabalho foi estudar a comunidade de abelhas solitárias através do método de ninhos-armadilha durante dois anos, em uma área de Cerrado e Mata de Galeria, no Parque Estadual do Mirador. Além disso, descrever a biologia de nidificação de Centris (Hemisiella) dichrootricha e analisar a composição florística do alimento de sua prole. A área de estudo está localizada no Parque Estadual do Mirador, município de Formosa da Serra Negra, Maranhão. O método empregado foi o de ninhos-armadilha de madeira nos diâmetros 6, 8, 10, 12, 14 e 16 mm, estes foram agrupados em conjuntos de 6 ninhos, totalizando 300 ninhos por área. Foi fundado um total de 101 ninhos pertencentes a 11 espécies de abelhas, das quais oito espécies ocorreram na Mata de Galeria e seis no Cerrado, sendo que a similaridade foi baixa entre os habitats (SJ = 0,27). Duas espécies foram dominantes na comunidade, Centris dichrootricha na Mata de Galeria e Centris tarsata no Cerrado. A diversidade e equitabilidade das espécies foram maiores na Mata de Galeria do que no Cerrado. O pico de fundação dos ninhos foi em novembro (2012 e 2013) e agosto (2013), não havendo correlação com a precipitação mensal (rCE = -0,061; pCE = 0,775 e rMG = 0,194; pMG = 0,365). Após 24 meses de coleta a curva de rarefação das espécies não atingiu a assíntota para ambos os habitats. Centris dichrootricha nidificou em 29 ninhos nos diâmetros 8, 10, 12 e 14mm. A espécie utilizou em maioria recursos provenientes do Cerrado, que consistia tanto no sedimento para compor as células quanto o material polínico e óleo floral. Tipos polínicos do gênero Byrsonima da família Malpighiaceae foram os mais representativos nas amostras. Nesse trabalho foram coletadas cinco espécies de Centris para um único estudo, sendo todas representadas na Mata de Galeria. Assim, o estudo revela a importância das áreas florestais como refúgio para algumas espécies de abelhas solitárias. A biologia da C. dichrootricha mostrou uma preferência por nidificar em cavidades com diâmetros variados e em locais sombreados da Mata de Galeria, também foi observada a espécie Euglossa amazonica que até então não havia sido registrada nidificando em ninhos-armadilha, principalmente em áreas de domínio do Cerrado. Além dessas duas espécies, o presente estudo contribui com a ampliação da distribuição geográfica de Centris bicornuta e Centris terminata, espécies estas que são pouco estudadas no Brasil.
24

Bees and wasps in agricultural landscapes: effects of dispersal corridors and land-use intensity at multiple spatial scales / Bienen und Wespen in Agrarlandschaften: Effekte von Ausbreitungskorridoren und Landnutzungsintensität auf verschiedenen räumlichen Skalen

Holzschuh, Andrea Alexandra Violetta 03 May 2006 (has links)
No description available.
25

Managing strawberry pollination with wild bees and honey bees: Facilitation or competition by mass-flowering resources?

Bänsch, Svenja 05 February 2019 (has links)
No description available.
26

Změny chování opylovačů v rostlinných populací o různé míře shlukovitosti / Changes in pollinator behaviour under different plant spatial aggregation

Štenc, Jakub January 2020 (has links)
Plants often occur aggregated into clusters and this spatial pattern is supposed to affect pollinator behaviour and pollen dispersal. Such pollinator reaction may influence reproductive success of zoogamous plant species both in terms of number of available mates and their genetic diversity (nearby growing plant individuals are also often closely related, especially in clonal plants). In the present thesis, I investigated the influence of plant spatial aggregation on pollinator behaviour and how this translates into pollen transfer. For that purpose, I carried three experiments. In the Experiment 1, I used potted plants placed into arrays and aggregated into four patches in order to track the pollen dispersal by means of a UV-dye pollen analogue. I manipulated distances between plants within clusters (dense × loose) and between clusters (near × far). I conducted this experiment for three plant species differing in their pollinator spectra. In the Experiment 2, I observed pollinator foraging sequences (sequences of visited plant individuals) under the same experimental design as for the first experiment, but I carried out this experiment for five plant species. In addition in one study species, Dianthus carthusianorum, I conducted the Experiment 3 to get better insight into pollination effectiveness...

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