• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • Tagged with
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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

Avifauna em fragmentos de Mata Atl?ntica, Pira?, RJ / Avifauna in Atlantic Rainforest fragments, Pira?, RJ

SILVA, Tatiane Lima da 02 March 2018 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-11-12T20:44:46Z No. of bitstreams: 1 2018 - Tatiane Lima da Silva.pdf: 3356978 bytes, checksum: 814f934a7b82c576f5248ee783fb8c66 (MD5) / Made available in DSpace on 2018-11-12T20:44:46Z (GMT). No. of bitstreams: 1 2018 - Tatiane Lima da Silva.pdf: 3356978 bytes, checksum: 814f934a7b82c576f5248ee783fb8c66 (MD5) Previous issue date: 2018-03-02 / CAPES / The Atlantic Rainforest is currently one of the most threatened biomes, considered global priority of conservation. Most of its forest remnants are in the form of small fragments. Forest fragmentation processes can lead to negative consequences for avifauna, such as the loss of specialized species, and increase in the proportion of opportunistic species. This study aimed to survey birds in forest fragments located in three private properties: Ip? Grange (IG), Monumento Grange (MG) and Fortaleza Farm (FF), located in Cacaria, Pira?, RJ. In the first chapter, a comparison was performed for the bird communities of the three sites regarding richness, frequency of occurrence, composition, abundance, diversity, equability and trophic guilds. In the second chapter, the biology of birds captured in mist networks in terms of capture and effort rate, seasonality, morphometric variation, body mass, feather molting and incubation plate were analyzed. The mist nets survey was conducted between August 2015 and February 2017, in which ten mist nets were opened from 06:00 a.m. to 17:00 p.m. Eight, eleven and nine field days were dispensed in SI, SM and FF, respectively. Four points counts were sampled in each fragment monthly between May 2016 and April 2017. A total of 205 species were recorded, with FF displaying the highest richness (147 sp) and the second highest diversity (H' = 4.38), MG displayed the second highest richness (130 sp) and the highest diversity (H' = 4.42), followed by IG, with the lowest wealth (122 sp) and diversity (H' = 4.26). Species composition varied significantly among the three sampled areas (F = 5,15; p = 0,0002), with each site presenting a different composition in relation to the others. A predominance of insectivorous and omnivorous species was observed in the three fragments. A total of 252 individuals were captured, distributed between 77 bird species. The dry season presented a higher catch rate (10.5%) when compared to the rainy season (6.6%), revealing a seasonal pattern. The highest body mass was observed for Leptotila rufaxilla (187.4g ? 16.72; n = 7,) and the lowest for Hylocharis cyanus (0.6g; n = 1). Beak length and total length presented the highest and the lowest coefficient of variation, respectively. When analyzing morphometric variations between sexes, in Manacus manacus, only wing, tail and tarsal length were significantly different. Of the total number of captured individuals, 71 (28.3%) displayed a brood patch and 37 (14.6%) were molting. The brood patch and molting were associated with season (?2 = 20.627; p = 0.000005 and ?2 = 8.363; p = 0.0038, respectively). In 16 individuals (6.34%), a molt and brood patch overlap was found, with molt associated with the brood patch (?2 = 4.408; p = 0.035). Although the study area was represented by small forest fragments with a certain degree of environmental impact, a significant local diversity was found, with the presence of endemic and endangered species. / A Mata Atl?ntica ? um dos biomas mais amea?ados atualmente e considerada como prioridade mundial de conserva??o. A maior parte de seus remanescentes florestais encontra-se na forma de pequenos fragmentos. O processo de fragmenta??o florestal pode trazer consequ?ncias negativas para a avifauna, como a perda de esp?cies especializadas e aumento de esp?cies oportunistas. Este trabalho teve como objetivo o levantamento de aves em fragmentos florestais localizados em tr?s propriedades particulares: o S?tio Ip? (SI), o S?tio Monumento (SM) e a Fazenda Fortaleza (FF), situados em Cacaria, Pira?, RJ. No primeiro cap?tulo foi realizado uma compara??o da comunidade de aves entre estes tr?s locais quanto a riqueza, frequ?ncia de ocorr?ncia, composi??o, abund?ncia, diversidade, equabilidade e guildas tr?ficas. No segundo cap?tulo, foram analisados aspectos da biologia das aves capturadas em redes de neblina quanto a taxa e esfor?o de captura, sazonalidade, varia??o morfom?trica, massa corporal, muda de penas e placa de incuba??o. O levantamento por redes foi realizado entre agosto/2015 a fevereiro/2017, na qual dez redes de neblina foram abertas das 06:00h ?s 17:00h. Foram dispensados oito, 11 e nove dias em campo no SI, SM e FF, repectivamente. Quatro pontos de escuta foram amostrados em cada fragmento mesalmente, entre maio/ 2016 a abril/2017. Foram registradas 205 esp?cies, na qual a FF foi local com a maior riqueza (147 sp) e a segunda maior diversidade (H?= 4,38). O SM apresentou a segunda maior riqueza (130 sp) e a maior diversidade (H?= 4,42). J? o SI demonstrou a menor riqueza (122 sp) e diversidade (H? = 4,26). A composi??o de esp?cies variou significativamente entre as tr?s ?reas amostradas (F = 5,15; p = 0,0002), na qual cada local apresentou uma composi??o diferente em rela??o aos demais. Houve predomin?ncia de esp?cies inset?voras e on?voras nos tr?s fragmentos. Foram capturados 252 indiv?duos distribu?dos em 77 esp?cies de aves. A esta??o seca apresentou maior taxa de captura (10,5%) quando comparada ? esta??o chuvosa (6,6%), revelando um padr?o sazonal. A maior massa corp?rea foi encontrada em Leptotila rufaxilla (187,4g ? 16,72; n = 7) e a menor em Hylocharis cyanus (0,6g; n = 1). O comprimento do bico e comprimento total apresentaram o maior e o menor coeficiente de varia??o, respectivamente. Na an?lise de varia??o morfom?trica entre sexos em Manacus manacus, apenas o comprimento da asa, da cauda e do tarso apresentaram diferen?as significativas. Do total de indiv?duos capturados, 71 (28,3%) apresentaram placa de incuba??o e 37 (14,6%) estavam com muda de penas. A placa de incuba??o e a muda foram associadas ? esta??o do ano (?2 = 20,627; p = 0,000005 e ?2 = 8,363; p = 0,0038, respectivamente). Em 16 indiv?duos (6,34%) foi encontrado sobreposi??o da muda e placa, estando a muda associada a placa de incuba??o (?2 = 4,408; p = 0,035). Apesar da ?rea de estudo ser representada por pequenos fragmentos florestais com um certo grau de impacto ambiental, foi encontrado uma significativa diversidade local, com a presen?a de esp?cies end?micas e amea?adas.
2

Comunidades de aves de sub-bosque de remanescentes florestais de mata atlântica do nordeste do Brasil: composição, diversidade e hábitat.

Melo, Daniela de Carvalho 23 April 2013 (has links)
Made available in DSpace on 2015-04-17T14:55:31Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2030208 bytes, checksum: a9ca9fd74d6c51300138eb942585c8c8 (MD5) Previous issue date: 2013-04-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Ecological analysis of the structure of understory bird communities of forest remnants of Atlantic Forest of Paraíba. South America is the region with the highest bird diversity in the world. The Atlantic Forest biome in Brazil is the second most diverse. Its portion in Paraíba integrates Pernambuco Endemism Centre, a region that is home of two-thirds of the bird species present in the biome. The present study investigated the bird communities in the understory of three Atlantic Forest remnants of Paraíba through the method of capture with mist nets. Ten nets were positioned in the forest understory in eight different points in each remnant, in a summit of 48 day samples, in a total effort of 2.895 hours-net. A total of 333 specimens of 44 species were captured, divided into 19 families. The recapture rate was 2%. The species with the highest representation were Arremon taciturnus (n = 40), Chiroxiphia pareola (n = 32) and Conopophaga melanops (n = 28), the latter being an endemic species considered as threatened in the Atlantic Forest with the status of vulnerable . Endangered species totaled 16% of the records and the same value was found for the endemic. Species richness among the three remnants did not differ (χ² = 0.667, d.f = 2, p = 0.7165), and according to the communities of birds found, diversity was considered low, with a predominance of dominant and generalists species. The species composition was little similar among the remnants, suggesting that the size, matrix and the availability of different microhabitats in each remnant may have influenced the species presence. The Reserva Particular do Patrimônio Natural Engenho Gargaú remnant was the one with the highest number of endemic and threatened species, as well as with the most understory insectivores, thus suggesting that this remnant is best conserved. / Análise ecológica da estrutura das comunidades de aves de sub-bosque de remanescentes florestais de Mata Atlântica da Paraíba. A América do Sul é a região que possui a maior diversidade de aves no mundo. No Brasil a Mata Atlântica é o segundo bioma mais diverso. A Mata Atlântica da Paraíba integra o Centro de Endemismo Pernambuco, uma região que abriga cerca de 2/3 de das espécies de aves presentes no bioma. O presente estudo investigou as comunidades de aves de sub-bosque de três remanescentes de Mata Atlântica da Paraíba através do método de captura com redes de neblina. Dez redes foram posicionadas no sub-bosque florestal em oito pontos distintos ao longo de cada remanescente, tendo sido realizadas 48 dias de amostragem ao todo, totalizando 2.895 horas-rede. Ao todo foram capturados 333 indivíduos de 44 espécies divididas em 19 famílias. A taxa de recaptura foi de 2%. As espécies com maior representatividade foram Arremon taciturnus (n = 40), Chiroxiphia pareola (n = 32) e Conopophaga melanops (n = 28), sendo esta última espécie endêmica e ameaçada da Mata Atlântica com status de vulnerável . As espécies ameaçadas totalizaram 16% dos registros e o mesmo valor foi encontrado para as espécies endêmicas. A riqueza de espécies entre os três remanescentes não diferiu (χ² =0,667; g.l = 2; p = 0,7165), e de acordo com as comunidades de aves encontradas, a diversidade foi considerada baixa, com predominância de espécies dominantes e generalistas. A composição das espécies foi pouco similar entre os remanescentes, sugerindo que o tamanho, a matriz e a disponibilidade de microhabitats distintos de cada um possam ter influenciado na presença das espécies. O remanescente Reserva Particular do Patrimônio Natural Engenho Gargaú foi o que apresentou o maior número de espécies endêmicas e ameaçadas, assim como insetívoros de sub-bosque, sugerindo assim que tal remanescente seja mais bem conservado.
3

Vtáčie spoločenstvá pozdĺž výškového gradientu na Kamerunskej hore z pohľadu odchytových dát / Bird Communities Along the Altitudinal Gradient on Mt. Cameroon: Perspectives from Mist Nets

Petruf, Miroslav January 2019 (has links)
in English Mt. Cameroon is a hotspot of diversity and endemism in Africa. Recent research of avian bird communities along the elevational gradient on Mt. Cameroon based on point counts has shown low-elevation plateau of species richness. At the same time, range-restricted montane populations of birds on Mt. Cameroon are unusually abundant if compared to lowland species. I analysed data on community composition, species richness and abundance of birds using an alternative quantitative method - 200 m of understory mist nets erected for three consecutive days across seven elevational plots along the forested gradient of the Mt. Cameroon. First, I looked at the technical limits of this method and confirmed the general opinion that they are better at detecting small birds below 33 g, and that they mostly detected fewer individuals after the first day and always detected fewer new species after the first day of mist-netting. Mist nets detected high proportions of ground-feeding and understory birds and low proportions of birds foraging in higher strata in the lowland forest, which has a scarce understory and a dense canopy. Mist nets recorded similar proportions of birds foraging in all forest strata in the vastly open mid-elevation forest, which has a dense herbaceous understory. They detected higher...

Page generated in 0.069 seconds