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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.
71

Effects of landscape heterogeneity and clearfell harvest size on beetle (Coleoptera) biodiversity in plantation forests

Pawson, Stephen January 2006 (has links)
Compared to natural forests, fast-growing plantations of exotic species such as Pinus radiata are often perceived as marginal habitat or unsuitable habitat for most native species. By studying Coleoptera (beetles) in a variety of landscape elements (pasture, native forest and different aged Pinus radiata stands) in a highly modified and fragmented landscape in New Zealand I aimed to determine the value of exotic plantation forests for native biodiversity, and how these species are affected by different sized clearfell harvest areas. Pitfall trap sampling of beetles showed that plantation forest stands can provide suitable complimentary habitat to native forest for many species. Rarefied species richness of Carabidae, Scarabaeidae and Scolytinae was not significantly different between habitats, however, habitat types differed significantly in their beetle community composition. Comparing different production habitats, Pinus radiata stands had a beetle community composition most similar to native forest. However, a small minority of species, e.g., Dichrochile maura, were restricted to native forest habitat highlighting the importance of retaining indigenous ecosystems within plantations. Unlike human modified habitats, native forests did not provide suitable habitat for exotic species. Clearfell harvesting is controversial and its impact on biodiversity is a key constraint for many forest certification programs, such as that administered by the Forest Stewardship Council (FSC). Despite this, no replicated manipulative experimental studies of the impact of different sized clearfell harvest areas on biodiversity have been undertaken at scales relevant to the New Zealand forest industry. One potential model of the impact of different clearfell harvest sizes is the concept of a threshold size. A threshold scenario may occur where clearfell harvest impacts increase at a rate disproportionate to the change in clearfell size over a small range of harvest areas, but impacts remain relatively unchanged either side of the threshold zone. I sampled Coleoptera in experimentally created 0.01, 0.05, 0.5, 5.0, 50 and 500 ha clearfells within Pinus radiata plantations in the central North Island of New Zealand. The wide range of clearfell harvest sizes, including some very small areas, such as 0.01 ha was instigated in an attempt to document potential clearfell harvest size thresholds. Rarefied native beetle species richness was higher in harvest areas compared to adjacent mature plantation stands. The beetle species richness in 5 ha and 500 ha harvest areas was significantly greater species than that in small 0.01 - 0.5 ha harvest areas. Although, the high beetle diversity recorded in 500 ha clearfells should be treated with caution due to confounding spatial autocorrelation. The degree of change in beetle community composition increased with increasing clearfell harvest area. Beetle assemblages in large harvest areas were less similar to their paired adjacent mature forest than smaller harvest areas. Although, constrained multivariate ordination techniques did show a short-term change in beetle species composition between recently clearfelled harvest areas of as little as 0.05 ha and adjacent mature P. radiata stands. The colonisation by open-habitat disturbance-adapted species was a key driver of this change, some species dispersed into clearfelled stands in significant densities within days post-harvest. Overall, there were no distinct short-term trends to the change in species richness as a function of increasing harvest area that would suggest an ecological impact threshold response. If short-term outcomes of clearfell harvesting are ameliorated by successful recolonisation, the long-term spatial arrangement of different aged stands becomes more important for the maintenance of biodiversity at the landscape level than short-term consequences of harvesting. By sampling selected beetle taxa in 1, 2, 4, 8, 16 and 26 year-old stands, I found that the abundance of seven out of eight of the species selected for analysis recovered to levels similar to those in adjacent mature forest within the timeframe of a single harvest rotation. Individual species utilised different aged stands, indicating different life-history strategies. For example, open-habitat, disturbance-adapted species such as Cicindela tuberculata and Sitona discoideus were prominent in young stands, and forest species such as Pycnomerus sophorae and Paracatops phyllobius were highly abundant in older stands. These alternative life-history strategies highlight the benefits of maintaining a mixture of different aged stands to increase biodiversity at the landscape level. This thesis fills an important gap in our knowledge of biodiversity in production landscapes. I show that plantation forests have value as complimentary habitat to native forest and they make an important contribution to the maintenance of biodiversity at the landscape level. Although clearfell harvesting is a severe disturbance to the forest ecosystem, the long-term recovery of beetle populations suggests that harvesting is not the key limiting factor to the enhancement of biodiversity in the plantation forests studied. This unusual situation is possibly the result of prior land-use history, as many plantations were established on degraded pastoral land, and harvest-sensitive species are unlikely to have survived this initial land-use change. As such, the severity of the long-term impacts of clearfell harvesting on biodiversity are likely to be context specific and will vary accordingly. The importance of spatial heterogeneity of habitat elements, including different aged plantation stands and native forest remnants, needs to be investigated in more detail to determine what limits biodiversity in this plantation landscape. Key points to consider are the proximity to, and proportion of, native forest cover in the landscape and the degree of connectivity among native remnants. It is these landscape-level attributes that may determine biodiversity at a regional scale, and more emphasis should be placed on landscape scale factors and there interaction with stand specific forest management practices. For example, the spatial mosaic of harvesting areas may need to be of a finer-scale when there are fewer native remnants within the landscape.
72

Fylogeneze a evoluce habitatových preferencí podčeledí Rygmodinae a Sphaeridiinae (Coleoptera: Hydrophilidae) / Phylogeny and evolution of habitat preferences of the subfamilies Rygmodinae and Sphaeridiinae (Coleoptera: Hydrophilidae)

Sýkora, Vít January 2015 (has links)
Subfamilies Rygmodinae and Sphaeridiinae together form approximately one third of the extant diversity within the family Hydrophilidae (Coleoptera: Polyphaga). Members of both these subfamilies inhabit wide spectrum of aquatic and terrestrial environments including specialized habitats such as phytotelmata, carrion or termite nests. So far, habitat shifts within these subfamilies have been only tested with a limited amount of taxa at the family level. Using a broader sampling and Bayesian and maximum likelihood methods, genus-level molecular phylogenetic analysis and divergence dating were performed. The dataset included 96 taxa, representing all major clades (genus groups) in both subfamilies, sequenced for two mitochondrial and two nuclear genes. A single shift from the aquatic to terrestrial environment in the Middle Jurassic was suggested, thus revealing both subfamilies and all tribes as ancestrally inhabiting decaying plant material and leaf litter. Secondary returns to aquatic habitats were suggested for two lineages of the Rygmodinae and several lineages belonging to tribes Coelostomatini and Megasternini. A single shift to flowers was revealed in the subfamily Rygmodinae. Similarly, single independent shifts to the inquiline lifestyle in tribes Omicrini and Megasternini were revealed. In...
73

Caracterização evolutiva das serina peptidases digestivas em insetos holometábolos / Evolutionary characterization of digestive serine peptidases in holometabolous insects

Dias, Renata de Oliveira 07 August 2014 (has links)
Tripsinas e quimotripsinas são classes de serina peptidases amplamente estudadas e fortemente responsáveis pela digestão proteica, pela clivagem de ligações peptídicas no lado carboxila de L-aminoácidos de cadeia lateral básica e hidrofóbica, respectivamente. Três processos regulam finamente a ação dessas peptidases: secreção, ativação do precursor (zimogênio) e o sítio de reconhecimento do substrato. No presente trabalho é apresentada uma análise filogenética detalhada das tripsinas e quimotripsinas de três ordens de insetos holometábolos, revelando características divergentes nas enzimas de Lepidóptera em relação a Coleóptera e Díptera. Em particular, o sub-sítio S1 das tripsinas foi observado como mais hidrofílico em Lepidóptera do que em Coleóptera e Díptera, enquanto os sub-sítios S2-S4 parecem mais hidrofóbicos, sugerindo diferente preferências pelo substrato. Além disso, Lepidóptera mostrou um grupo de tripsinas bastante específico a um grupo taxonômico, compreendendo somente proteínas de espécies da família Noctuidae. Evidências de eventos de auto-ativação facilitada foram também observadas em todas as ordens de insetos estudadas, com as características do motivo de ativação do zimogênio complementárias ao sítio ativo das tripsinas. Em contraste, as quimotripsinas de insetos não parecem ter uma história evolutiva peculiar com respeito a, por exemplo, seus homólogos em mamíferos. Em geral, os presentes resultados sugerem que a necessidade de uma rápida taxa de autoativação fez os insetos holometábolos selecionarem grupos especializados de tripsinas com altas taxas de auto-ativação e também destacam que a evolução das tripsinas culminou em um grupo especializado de enzimas em Lepidóptera. / Trypsins and chymotrypsins are well-studied classes of serine peptidases largely responsible for the digestion of proteins by cleavage of the peptide bond at the carboxyl side of basic and hydrophobic L-amino acids, respectively. Three processes mainly regulate the action of these peptidases: secretion, precursor (zymogen) activation and substrate-binding site recognition. In the present work is presented a detailed phylogenetic analysis of trypsins and chymotrypsins in three orders of holometabolous insects revealing divergent characteristics in the Lepidoptera enzymes in relation to Coleoptera and Diptera. In particular, trypsin subsite S1 was observed to be more hydrophilic in Lepidoptera than in Coleoptera and Diptera, whereas subsites S2-S4 appeared more hydrophobic, suggesting different substrate preferences. Furthermore, Lepidoptera displayed a very specific taxonomic trypsin group, only encompassing proteins from the Noctuidae family. Evidences for facilitated trypsin auto-activation events were also observed in all the insect orders at hand, with the characteristic zymogen activation motif complementary to the trypsin active site. In contrast, insect chymotrypsins did not seem to have a peculiar evolutionary history with respect to e.g. their mammal counterparts. Overall, the present findings suggest that the need for fast digestion made holometabolous insects evolve specialized groups of trypsins with high autoactivation rates and highlight that the evolution of trypsins culminated in a specialized group of enzymes in Lepidoptera.
74

Aspectos biológicos e técnica de criação de Metallactus sp. (Coleoptera: Chrysomelidae: Cryptocephalinae) em Eucalyptus urophylla S.T. BLAKE. / Metallactus sp. (coleoptera: chrysomelidae: cryptocephalinae): biological aspects and rearing technique on eucalyptus urophylla s.t. blake.

Perecin, Moisés Francisco 01 September 2003 (has links)
Esta pesquisa teve por objetivos avaliar os aspectos biológicos de Metallactus sp. em Eucalyptus urophylla e desenvolver uma técnica de criação do inseto em laboratório. As condições ambientais foram: temperatura 25±1°C, umidade relativa de 90±5% e fotofase de 14 horas. Os parâmetros biológicos avaliados foram: duração, viabilidade da fase larval e número de ínstares larvais; duração, viabilidade da fase pupal e peso da escatoteca; longevidade de machos e fêmeas, razão sexual, dimorfismo sexual, período de pré-oviposição, período de oviposição, número de ovos por fêmea; período de incubação e viabilidade dos ovos; duração e viabilidade do ciclo (ovo-adulto) e tabela de vida de fertilidade. / This paper deals with the biological aspects of Metallactus sp. on Eucalyptus urophylla and the development of a technique to rear this insect in laboratory (25±1º C; 90±5% RH; 14-hour photophase). The following parameters were evaluated: duration, viability and number of instars of the larval stage; duration and viability of the pupal stage; case weight; longevity of male and female adults; sex ratio; sexual dimorphism; preoviposition period; oviposition period; number of eggs per female; egg period and egg viability; duration and viability of the life cycle (egg-adult period); and fertility life table.
75

Coleópteros (insecta) associados às estruturas reprodutivas de espécies florestais arbóreas nativas no Estado de São Paulo. / Coleoptera (insecta) associated to the reproductive structures of native forest tree species in the state of São Paulo, Brazil.

Zidko, Alexsandro 04 April 2002 (has links)
As espécies florestais arbóreas nativas apresentam interações com coleópteros que se desenvolvem no interior das estruturas reprodutivas. Foram estudadas as seguintes espécies florestais arbóreas nativas e identificados os coleópteros a elas associados: Pterogyne nitens Tul. (amendoim-bravo) - Tricorynus sp. (Anobiidae) e Ormiscus sp. (Anthribidae); Stryphnodendron adstringens (Mart.) Cov. (barbatimão) - Acanthoscelides sp. (Bruchidae); Cassia grandis L. f. (cássia-grande) - Pygiopachymerus lineola (Bruchidae); Tabebuia alba (Cham.) Sandwith (ipê-amarelo) - Sitophilus linearis (Curculionidae); Hymenaea courbaril var. stilbocarpa (Hayne) Lee & Lang (jatobá) - Tricorynus sp. (Anobiidae); Chorisia speciosa (A. St. - Hil.) Dawson (paineira) - Lonchophorus obliquus (Curculionidae); Caesalpinia ferrea var. leiostachya Benth. (pau-ferro) - Pityophthorus sp. (Scolytidae); Aspidosperma polyneuron Müll. Arg (peroba) - Tricorynus sp. (Anobiidae) e Rhinochoenus stigma (Curculionidae); Enterolobium contortisiliquum (Vell.) Morong (timbó) - Stator pacarae(Bruchidae). / This paper deals with the identification of Coleoptera (species and family) associated to the reproductive structures of the following native forest tree species: Pterogyne nitens Tul. ("amendoim-bravo") - Tricorynus sp. (Anobiidae) and Ormiscus sp. (Anthribidae); Stryphnodendron adstringens (Mart.) Cov.("barbatimão") - Acanthoscelides sp. (Bruchidae); Cassia grandis L. f. ("cássiagrande") - Pygiopachymerus lineola (Bruchidae); Tabebuia alba (Cham.) Sandwith ("ipê-amarelo") - Sitophilus linearis (Curculionidae); Hymenaea courbaril var. stilbocarpa (Hayne) Lee & Lang ("jatobá") - Tricorynus sp. (Anobiidae); Chorisia speciosa (A. St. - Hil.) Dawson ("paineira") - Lonchophorus obliquus (Curculionidae); Caesalpinia ferrea var. leiostachya Benth. ("pau-ferro") - Pityophthorus sp. (Scolytidae); Aspidosperma polyneuron Müll. Arg ("peroba") - Tricorynus sp. (Anobiidae) and Rhinochoenus stigma(Curculionidae); Enterolobium contortisiliquum (Vell.) Morong ("timbó") - Stator pacarae (Bruchidae).
76

Respostas dos besouros (INSECTA: COLEOPTERA) a pressões pastoris em campos naturais no sul do Brasil

Viegas, Gustavo Vinícius January 2018 (has links)
O crescimento populacional humano e o consumismo exacerbado têm elevado as demandas na produção de alimentos e gerado uma intensificação rural, se tornando um dos principais direcionadores do declínio da biodiversidade. O manejo de gado está se intensificando e expandindo, muitas vezes às custas da derrubada de áreas florestais. Mas manejar o gado em campos naturais pode ser uma estratégia para a conservação desses ecossistemas. Os métodos de manejo determinam as comunidades de campos, de forma que baixa pressão de pastejo parece promissor para a conservação. De modo geral, direcionadores ambientais tendem a gerar padrões na diversidade em grande escala, enquanto a competição contribui para determinar a coexistência local. Contudo, os processos de montagem das comunidades podem diferir entre regiões. Assim, especialmente filtros ambientais e interações bióticas atuam dinamicamente e direcionam o padrão da comunidade. As espécies que persistem se diferenciam especialmente em grupos alimentares conforme os recursos disponíveis, e competem dentro desses grupos conforme os nichos dos consumidores se sobrepõem. Além disso, as características morfológicas individuais podem facilitar ou restringir sua habilidade em persistir em um ambiente, ao passo que mediam os processos ecossistêmicos. Os insetos representam o maior componente da biodiversidade em ecossistemas terrestres, e são considerados sensíveis às condições ambientais. Coleoptera é a ordem de insetos com maior riqueza em espécies, que abrange uma larga extensão de grupos funcionais, e são sensíveis às variações ambientais. O objetivo desta Tese foi testar se as comunidades de Coleoptera refletem diferenças nas pressões pastoris exercidas pelo gado. Essa Tese revela resultados inéditos para cada uma das abordagens empregadas, especialmente considerando a escala regional do experimento. A diversidade de besouros residentes do solo mostrou um padrão geral com relação positiva ao pastejo enquanto os residentes da vegetação demonstraram uma relação negativa ao pastejo. Os herbívoros residentes da vegetação são bastante sensíveis ao pastejo do gado, e declinam com o aumento da intensidade, enquanto que os predadores residentes da vegetação parecem responder positivamente a uma vegetação mais arbustiva do que de gramíneas. Além disso, parece que, potencialmente, os besouros também respondem com seus atributos morfológicos às diferenças na estrutura da vegetação conforme a intensidade de pastejo. O pastejo de baixa intensidade parece uma boa opção para beneficiar a conservação da biodiversidade. Contudo, manejar campos naturais com apenas uma técnica não permite conservar igualmente os besouros campestres. / Human population growth and exacerbated consumerism have raised the demands on food production and generated rural intensification, becoming one of the main drivers of biodiversity decline. Livestock management is intensifying and expanding, often at the cost of clearing forested areas. However, managing livestock in natural grasslands may be a strategy for the conservation of these ecosystems. Management methods determines the communities in grasslands, so that low pressure grazing seems promising for conservation. In general, environmental drivers tend to generate diversity patterns at large scales, while competition contributes to determining local coexistence. However, the assembly processes of communities may differ between regions. Thus, environmental filters and biotic interactions, especially, act dynamically and direct the community pattern. Species may persist when different, especially according to feeding groups, and compete within these groups when consumer niches overlap. In addition, individual morphological traits may facilitate or restrict a species ability to persist in an environment, while at the same time mediating ecosystem processes. Insects represent the largest component of biodiversity in terrestrial ecosystems, and have been considered sensitive to environmental conditions. Coleoptera is the insect order with the largest species richness, covering a wide range of functional groups, and are sensitive to environmental variations. The aim of this thesis was to test whether Coleoptera assemblages reflect differences in the pastoral pressures exerted by livestock. Ground-dwelling beetle diversity showed a general pattern of positive relationship with grazing while grass-dwellers showed a negative relationship with grazing. Grass-dweller herbivores are quite sensitive to livestock effects, and decline with increasing grazing intensity, while grass-dweller predators appear to respond positively to scrubs rather than to grass vegetation. In addition, it seems that, potentially, beetles also respond with their morphological traits to differences in vegetation structure according to grazing intensity. Some of these results are unprecedented, especially considering the regional scale of the experiment. Low intensity grazing seems to be a good option to benefit biodiversity conservation. However, managing grasslands with a single technique would not provide grassland beetles conservation equally.
77

Seleção de genes cry de Bacillus thuringiensis que codificam proteínas tóxicas a insetos-praga da cultura do arroz / Screening of bacillus thuringiensis cry genes which codify toxic proteins to the insects pest of rice-crop

Pinto, Laura Massochin Nunes 14 January 2002 (has links)
Made available in DSpace on 2015-03-05T16:19:34Z (GMT). No. of bitstreams: 0 Previous issue date: 14 / Nenhuma / O presente trabalho objetivou a seleção de genes cry de Bacillus thuringiensis (Bt) que codificam delta-endotoxinas ativas contra insetos-praga do arroz, em especial contra os representantes das ordens Lepidoptera (Spodoptera frugiperda), Coleoptera (Oryzophagus oryzae) e Hymenoptera (Acromyrmex sp.), que poderão ser utilizadas no manejo de populações desses insetos. Os resultados da PCR, com os isolados de Bt obtidos das amostras de solos, revelaram a presença de oito diferentes perfis genéticos, homogeneamente distribuídos nos solos do Rio Grande do Sul, predominando os genes cry9 (39,1%). A análise protéica de Bt, por SDS-PAGE, identificou 14 famílias de proteínas Cry, que possivelmente são codificadas pelos genes presentes nos isolados analisados, além de proteínas desconhecidas que podem representar novos genes cry ainda não caracterizados. Considerando os dados da pré-seleção por PCR, entre os 46 isolados de Bt, oriundos de amostras de solos, 56,5 e 21,7% foram potencialmente específicos aos lepidóptero / This work, which is part of the Preservation and Management of Ecossystems and Wild Life research line, has as its aim the selection of the Bacillus thuringiensis cry genes that codify delta-endotoxins active against rice pest insects, representatives of the Lepidoptera (Spodoptera frugiperda, Noctuidae), Coleoptera (Oryzophagus oryzae, Curculionidae) and Hymenoptera (Acromyrmex lundi, Formicidae) orders, which can be used for the management of those insect populations. In order to select B. thuringiensis active against S. frugiperda and O. oryzae there have been used isolates from soil samples that had been collected in agricultural areas in Rio Grande do Sul, and they had gone through the prediction of insecticidal activity by the Polimerase Chain Reaction (PCR), with the primers that magnify DNA fragments which correspond to lepidopterans-specific cry1, cry2 and cry9 genes and coleopterans-specific cry3, cry7 and cry8 genes. The preselected isolates during this phasis of the research, have been assessed re
78

Din?mica populacional da entomofauna deterioradora associada a tr?s ambientes no Sistema Integrado de Produ??o Agroecol?gica (SIPA) em Serop?dica, RJ / Population dynamics of deteriorater entomofauna associated with three environments in the Integrated Agroecological Production System (IAPS) in Serop?dica/RJ

SANTOS, Tamires Medeiros dos 01 March 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2016-10-20T17:01:43Z No. of bitstreams: 1 2016 - Tamires Medeiros do Santos.pdf: 5083938 bytes, checksum: 468695a43a5e90373cf9817865775cc6 (MD5) / Made available in DSpace on 2016-10-20T17:01:43Z (GMT). No. of bitstreams: 1 2016 - Tamires Medeiros do Santos.pdf: 5083938 bytes, checksum: 468695a43a5e90373cf9817865775cc6 (MD5) Previous issue date: 2016-03-01 / CAPES / The searching for development of sustainable agricultural systems has shown satisfactory results from economic, social and agronomic perspectives. However, it is necessary to evaluate these systems about their impacts on the environment. The knowledge of insect fauna is essential in monitoring the impacts caused by anthropic action, and the Coleoptera order, because it?s the group with biggest richness, has been the focus of many studies that evaluate environmental conditions. Given the above, the objective of this study was to analyze the occurrence of beetles captured per impact trap in the period from November 2014 to November 2015, in three environments with different ecological characteristics, and assess the influence of climatic variables in the occurrence of Scolytinae group. In order to conduct the study, the chosen experimental area is located in the Integrated Agroecological Production System (IAPS), in the municipality of Serop?dica/RJ. Were selected, inside the IAPS, three distinct environments: organic coffee production (OC), agroforestry (AFS) and organic coffee (FF). Climatic data was obtained by an automatic station, of the National Institute of Meteorology (INMET), located in Serop?dica, named Agricultural Ecology Station. In each environment, there were set four ethanolic semifunil model traps. The traps were kept in the field in the period from November 2014 to November 2015, and every seven days the storers containers went replaced and the attractive baits were renewed using commercial ethanol (alcohol 96 ?). The samples were forwarded to the Laboratory of Wood Deterioration and Forestry Entomology, at the Rural Federal University of Rio de Janeiro ? UFRRJ, to perform the triage. The insects were separated by trap and their respective area where they were collected, and then identified. All insects collected were quantified and only the coleoptera were identified at the level of family and subfamily. However, four groups of borers beetles (Cerambycidae, Bostrichidae and, Curculionidae: Platypodinae and Scolytinae) were evaluated separately. The highest number of insects was found in the AFS, followed by the organic coffee and the agroforestry system. Nearly 75% of the trapped borers beetles were Scolytinae. The agroforestry system was the environment with more coleoborers, due to the management carried out in the area, because there is a greater diversity of plant species, thus requiring constant maintenance. Seasonality influenced in the number of Scolytinae in the three environments. The temperature, atmospheric pressure and wind speed influenced the Scolytinae fluctuation only in the organic coffee and the agroforestry system, considering that the composition of the forest fragment provides favorable conditions for its microclimate stability. / A busca por desenvolvimento de sistemas agr?colas sustent?veis tem demonstrado resultados satisfat?rios do ponto de vista econ?mico, social e agron?mico. Entretanto ? necess?rio avaliar tais sistemas quanto aos impactos gerados ao meio ambiente. O conhecimento da entomofauna ? essencial no acompanhamento de impactos causados pela a??o antr?pica e, a Ordem Coleoptera, por ser o grupo de maior riqueza, tem sido alvo de muitos estudos para avalia??o de condi??es ambientais. Diante disto, o objetivo deste trabalho foi analisar a ocorr?ncia de cole?pteros capturados por armadilha de impacto, no per?odo de novembro de 2014 a novembro de 2015, em tr?s ambientes com caracter?sticas ecol?gicas distintas e, avaliar a influ?ncia de vari?veis clim?ticas na ocorr?ncia do grupo Scolytinae. Para a realiza??o do estudo, a ?rea experimental escolhida est? localizada no Sistema Integrado de Produ??o Agroecol?gica (SIPA), no munic?pio de Serop?dica, RJ. Foram selecionados dentro do SIPA tr?s ambientes distintos: produ??o de caf? org?nico (CO), sistema agroflorestal (SAF) e fragmento florestal (FF). Os dados clim?ticos foram obtidos pela esta??o autom?tica do Instituto Nacional de Meteorologia (INMET) localizada em Serop?dica, esta??o Ecologia agr?cola. Em cada ambiente foram instaladas quatro armadilhas etan?licas modelo Semifunil. As armadilhas foram mantidas no campo no per?odo de novembro de 2014 a novembro de 2015 e, a cada sete dias os recipientes armazenadores foram substitu?dos e as iscas atrativas renovadas com etanol comercial (?lcool 96?). As amostras foram encaminhadas ao Laborat?rio Deteriora??o da madeira e Entomologia Florestal da Universidade Federal Rural do Rio de Janeiro - UFRRJ para a realiza??o da triagem. Os insetos foram separados por ?rea e armadilha, de onde foram coletados e, em seguida, identificados. Todos os insetos coletados foram quantificados e, os cole?pteros foram identificados em n?vel de Fam?lia e Subfam?lia. No entanto, quatro grupos de cole?pteros broqueadores (Cerambycidae, Bostrichidae e, Curculionidae: Platypodinae e Scolytinae) foram avaliadas separadamente. O maior n?mero de cole?pteros foi encontrado no sistema agroflorestal seguido do caf? org?nico e do fragmento florestal. Cerca de 75% dos cole?pteros broqueadores registrados foram Scolytinae. O sistema agroflorestal foi o ambiente com maior n?mero de cole?pteros broqueadores, devido ao manejo realizado na ?rea, pois ocorre maior diversidade de esp?cies vegetais, consequentemente, exigindo manuten??o constante. A sazonalidade influenciou no n?mero de Scolytinae nos tr?s ambientes. A temperatura, a press?o atmosf?rica e a velocidade do vento influenciaram na flutua??o de escolit?neos apenas no caf? org?nico e no sistema agroflorestal, considerando que a composi??o do fragmento florestal proporciona condi??es favor?veis para a estabilidade microclim?tica.
79

Interação trófica entre Coleoptera e basidiomas de Polyporales e Hymenochaetales (Fungi : Basidiomycota) / Trophic interaction between Coleoptera and Basidiomes of Polyporales and Hymenochaetales (Fungi: Basidiomycota)

Graf, Letícia Vanessa January 2008 (has links)
O consumo de qualquer parte do organismo de um fungo denomina-se fungivoria e são raros os estudos que abordam a temática da interação trófica entre suas estruturas reprodutivas (basidiomas) e os insetos. Mesmo que seja um hábito alimentar freqüente entre os coleópteros, com muitas famílias obrigatoriamente fungívoras, pouco se conhece sobre a estruturação dessa assembléia. Entretanto, sabese que existem preferências por determinadas espécies de fungos, tanto para a postura dos ovos quanto para o próprio consumo. Algumas questões que este estudo aborda referem-se à riqueza e à especificidade dos besouros fungívoros. Adicionalmente investigarei a influência da taxonomia dos fungos, bem como da consistência e do sistema hifal dos basidiomas para o processo de seleção que as espécies de besouros realizam. Também foi verificado se a posição taxonômica dos besouros está relacionada com o grupo de fungos que estes utilizam ou com a consistência dos seus basidiomas. Foram realizadas oito coletas em um ambiente de Floresta Ombrófila Mista no Estado do Rio Grande do Sul, obtendo-se 376 indivíduos das Ordens Polyporales e Hymenochaetales. Estes espécimes foram mantidos individualizados em laboratório por três meses para a constante retirada dos besouros adultos e então dissecados. Todos os fungos que apresentaram besouros fungívoros associados (N = 207) foram identificados e totalizaram 40 espécies. Os coleópteros totalizaram 447 ocorrências e foram classificados em 90 morfoespécies e 20 famílias, sendo Ciidae e Staphylinidae as mais representadas. Os basidiomas foram classificados quanto às suas classes de consistência seguindo um gradiente de durabilidade e rigidez. A riqueza de besouros variou conforme a espécie do hospedeiro e não foram encontrados fatores que influenciam a variação de riqueza de besouros em fungos. A especificidade dos besouros não apresentou relação com a longevidade dos basidiomas. Também se verificou que a posição taxonômica dos fungos, bem como a consistência dos basidiomas, interferem na escolha do hospedeiro pelos besouros. Além disso, se observou que besouros mais relacionados filogeneticamente não utilizam uma assembléia de fungos mais semelhante nem basidiomas com consistências semelhantes. Isso demonstra que a habilidade em consumir as mesmas espécies não está tão relacionada com a filogenia dos besouros como ocorre com os herbívoros. / Fungivory is the consumption of any part of the fungi organism and just a few studies were done about the trophic interactions of its reproductive structures, so called basidiomes, and insects. Even though this is a disseminated habit among Coleoptera, which has many obligated fungivores families, little is known about its community organization. However, there have been works about feeding preferences and oviposing sites of some fungi species. Some of the questions of this study refer to richness and specificity of fungivores beetles on their host. It was also investigated the influence of fungi taxonomy, basidiomes consistency and hyphal system for the selection process of the beetle species, as well as the importance of the taxonomic position of the beetles regarding the host group they use and the basidiome´s consistency. The basidiomes of Polyporales and Hymenochaetales Orders were collected in an Araucaria angustifolia forest of Rio Grande do Sul State. It was obtained 376 fungal individuals, which were kept in the laboratory, individually separated in containers for three months, while the newly emerged beetles were captured, and the fungi were dissected afterwards. All individuals of fungi that had associations (207) were identified (40 species). It was found 447 occurcences of Coleoptera, which were classified in 90 morphospecies belonging to 20 families, with Ciidae and Staphylinidae being the most abundant. The basidiomes where classified by its consistency, following a longevity and hardness gradient. Beetle richness varied among fungal species and no factors that might influence the richness variation in fungi was found. Its specificity did not seem to be related to the longevity of the basidiomes. It was also verified that the fungus taxonomy as well as the consistency of its basidiomes demonstrated some importance for the process of host selection. Regarding the Coleoptera taxonomy, it was not verified that the more phylogenetic related ones use a more similar group of hosts or basidiomes that have similar consistency. This demonstrates that the ability to feed on the same species is not so related to the phylogeny of fungivore beetles as it occurs with herbivores.
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Gamla tallars betydelse för biologisk mångfald på Gotland

Lars, Enström January 2009 (has links)
<p>Modern methods for managing pine (<em>Pinus sylvestris</em>) create homogenized forests. This decreases nature’s potential for biodiversity and might threaten species in need of different types of milieu. The main purpose of this study was to investigate how important older pine trees are for biodiversity. In the Hall-Hangvar Reserve in the north-west part of Gotland, insects collected from traps showed that more species were found in old or dead trees compared to younger pine trees. A statistically significant difference was found for Coleoptera (beetles). The taxons of greatest interest for this study were Coleoptera and Hymenoptera (wasps). Certain families of Hymenoptera use ducts made by larvae from some families of Coleoptera.These larvae also serve as prey. Relevance concerning enviromental importance to species and diffrenences in inhabiting the three stages of pine trees was of importance.</p>

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