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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.
1

Carabidae (Coleoptera) : análise de fauna e flutuação populacional, em áreas de frutíferas e capoeira, Belém, Pará /

Oliveira, Helcio Hertz Gomes de January 2016 (has links)
Orientador: Francisco Jorge Cividanes / Coorientador: Ivan Carlos Fernandes Martins / Banca: Eduardo Suguino / Banca: Arlindo Leal Boiça Junior / Banca: Sérgio Ide / Banca: Sérgio Antônio de Bortoli / Resumo: Este trabalho teve por objetivo caracterizar a diversidade e equitabilidade de espécies, similaridade de comunidades, flutuação populacional e influência de fatores metereológicos de Carabidae em fragmento florestal, capoeira do Black, e pomar de frutíferas: consórcio cupuaçu,Theobroma grandiflorum(Willd.ex Sreng.) K.Schum (Malvaceae)), taperebá (Spondias monbim L. (Anacardiacae)), muruci, (Byrsonima crassifolia ((L.) (Rich.) (Malpiguiaceae)), abricó, (Mammea americana Linn. (Clusiaceae)) e bacuri (Platonia insignis Mart. (Clusiaceae)). As amostragens foram realizadas mensalmente de janeiro a julho de 2014 e quinzenalmente de agosto de 2014 a julho de 2015, por meio de armadilhas tipo alçapão, instaladas na área experimental da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA). Foram coletadas 207 espécimes de carabídeos pertencentes a 15 espécies.As espécies predominantes foram: Scarites sp. 1,Marsyas lampronotus Tschitscherine, 1901, Tetragonoderus laevigatus Chaudoir,Clivina sp. 1 e Aniara sepulchralis (Fabricius).M. lampronotus,ocorreu somente na capoeira em consórcio, cupuaçu e taperebá. Nacapoeira registrou-se a menor diversidade de espécies. A maior diversidade de espécies de carabídeos ocorreu em muruci e abricó, enquanto o maior número de indivíduos ocorreu em bacuri. Com o aumento da umidade relativa ocorreu redução da densidade populacional de A.sepulchralis. / Abstract: This study aimed to characterize the diversity and equitability of species, similarity of species and fluctuation of Carabidae population and the influence of meteorological factors in forest fragment, capoeira do Black, and fruit orchard: Consortium of cupuaçu, Theobroma grandiflorum (Willd.ex Sreng.) K. Schum(Malvaceae)), taperebá (Spondias monbim L. (Anacardiacae)), muruci, (Byrsonima crassifolia ((L.) (Rich.) (Malpiguiaceae)), abricó, (Mammea americana Linn. (Clusiaceae)) e bacuri (Platonia insignis Mart. (Clusiaceae)). The samplings were carried monthly from January to July 2014 and fortnightlyof August 2014 to July 2015, through the pitfall trap, installed in the experimental area of the Brazilian Agricultural Research Corporation (EMBRAPA). There were collected 207 especimens of Carabidae, ordered in 15 species. The predominant species were: Scarites sp. 1, Marsyas lampronotus Tschitscherine, 1901, Tetragonoderus laevigatus Chaudoir, Clivina sp. 1 and Aniara sepulchralis (Fabricius). M.lampronotusoccurred in the capoeira and consortium cupuaçu e taperebá. In the capoeira was registered the lowest species diversity. The biggest species diversity of the Carabidae occurred in muruci and abricó, while the largest number of individuals occurred in bacuri. The increase in relative humidity influence on reducing the population density of the beetle A. sepulchralis. / Doutor
2

Impacts of illegal trapping and plantation forestry on herpetofaunal populations

Sung, Yik-hei., 宋亦希. January 2012 (has links)
Globally, as many as 30% of amphibians and 23% of reptile species are threatened and require urgent conservation action. The major threats are primarily caused by anthropogenic activities. This research aimed to investigate the impacts of two anthropogenic threats, over-exploitation and habitat changes on herpetofaunal populations in Hong Kong. Platysternon megacephalum has been heavily depleted because of severe hunting pressure for the food and pet trades. Low densities of individuals and few remaining intact populations have limited our ability to study their ecology. I conducted mark-recapture and radio-telemetry studies on P.megacephalum populations in five streams in Hong Kong, one of which was free from trapping, over 34 months (2009–2011) to investigate the impacts of illegal trapping on populations of P.megacephalum and their spatial ecology and growth. Illegal trapping was associated with the absence of large adults, smaller body sizes of adults and skewed ratios of juveniles to adults. Home ranges were relatively small with a mean 100% minimum convex polygon 996m2. Males moved longer distances than females and both sexes moved longer distances in wet seasons. P.megacephalum was highly aquatic, preferring to stay in pools, and their microhabitat preferences were affected by stream width and depth, and substrate types. Juvenile P.megacephalum grew rapidly, with growth declining after attainment of sexual maturity. The average ages of sexual maturation were eight years for females. Illegal trapping remains the major threat to P.megacephalum populations and I recommend that regulatory personnel identify key streams and patrol regularly against illegal trapping to safeguard remaining populations. In Hong Kong, large areas of primary forest have been replaced by secondary forests and plantations, and changes in tree species composition have often led to alteration of associated plant and animal communities. I examined the herpetofaunal assemblages in secondary forests and exotic Lophostemon confertus plantations. Amphibian abundances were higher in secondary forests while reptile abundance, species richness of amphibian and reptiles were similar. Secondary forests provided better habitats for amphibians and I recommend the planting of a mixture of native tree species and the thinning of exotic trees in future plantation management efforts in South China. Our knowledge about the effectiveness of different herpetofaunal survey methods in Southeast Asia is limited. To fill the information gap, I examined the effectiveness of three survey methods, including transect surveys, pitfall traps and coverboards, for sampling terrestrial herpetofauna. Transect surveys were most effective at sampling species richness and pitfall traps were most efficient in capturing high numbers of reptiles. The results of this study will aid researchers in assessing the feasibility of and choosing herpetofaunal survey methods in Southeast Asia. Despite the severe threats that herpetofauna are facing, our understanding of their ecology and conservation needs remains limited. More research and the initiation of monitoring programs for herpetofauna, strengthened enforcement of existing regulations, and proper habitat management are crucial for the conservation of herpetofauna in South China. / published_or_final_version / Biological Sciences / Doctoral / Doctor of Philosophy

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