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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

Hur skiljer sig faunan av barkborrar (Scolytinae) och långhorningar (Cerambycidae) mellan nyligen död ekved av diametrarna 0-30 cm i brandfält och utanför dessa inom Hornsö-området?

Carrington, Simon January 2024 (has links)
Our Swedish forests have always been under the exposure of fire, more or less. The historical influence of fires, have made some species bound to these habitats or temporarily using them. Among these species, beetles (Coleoptera) are numerous. One of the tree species with the most historic influence of fire as well as inhabiting a great beetle-fauna is the oak (Quercus sp.). An area with an especially rich beetle-fauna tied to the oak and a extensive history of fire is the Hornsö-area in Smaland.  The purpose of this study is to investigate how the beetle-fauna and number of individuals differs between newly dead oaks in burnt areas and outside them, in the Hornsö area. The two studied families was long-horn beetles (Cerambycidae) and bark beetles (Scolytinae). The beetles were reared from hatching boxes. The study aims to fil in knowledge gaps about which species that are pyrophilous respectively fire-favoured. In the future this could contribute to a better knowledge about how to manage the oakforests and it`s associated species. The results shows that bark beetles are more numerous on burned oaks, that have died recently where the fire have been limited to the ground. It also seems like bark beetles are more numerous on smaller diameter trees. Future studies should focus on studying wood a wider range of diameters as well as more trees and samples. A longer time for rearing the insects would also be desirable.
2

Idade de fêmeas colonizadoras de Hypothenemus hampei (Ferrari) e sua resposta aos voláteis de flores de café, Coffea arabica L. / Age of colonizing Hypothenemus hampei (Ferrari) females and their response to volatiles of coffee, Coffea arabica L., flowers

Silva, Weliton Dias da 15 April 2014 (has links)
A idade das fêmeas colonizadoras de Hypothenemus hampei (Ferrari) durante o abandonamento do hospedeiro, assim como sua resposta aos voláteis de flores de café, Coffea arabica L. var. Tupi, foram investigadas neste trabalho. Um dispositivo experimental que simulasse as condições de dentro do fruto de café e permitisse a observação da saída dos insetos foi utilizado para a determinação da idade das fêmeas colonizadoras. Em média, os besouros apresentaram 15 dias de idade no momento em que abandonaram o dispositivo experimental. Nesta idade as fêmeas estavam acasaladas, possuiam o tegumento totalmente melanizado, foram capazes de voar e produzir ovos viáveis. Os voláteis de flores de café, foram coletados por aeração, analisados por GC-EAD e GC-MS, e testados em bioensaios olfatométricos. As fêmeas colonizadoras de H. hampei foram atraídas pelos voláteis de flores de café. Dos 50 compostos encontrados nos extratos naturais, sete foram eletrofisiologicamente ativos aos insetos. Destes sete, somente metil salicilato, neral e geranial puderam ser identificados, e a mistura de seus padrões sintéticos foi a mais atrativa nos bioensaios olfatométricos. Tomados juntos, estes resultados trazem novas informações sobre a bioecologia e ecologia química da broca-do-café, as quais poderão ser usadas futuramente em pesquisas de base e naquelas focadas no desenvolvimento de novas estratégias de manejo para H. hampei em cafezais. / The age of Hypothenemus hampei (Ferrari) females during the host abandonment, as well as their response to coffee flower volatiles were determinated under laboratory conditions. A experimental device that simulated the conditions inside a coffee berry, and that allowed the observation the insects coming out was used to determinate the age of colonizing females. On average, the beetles were 15 d-old at the moment they abandoned the experimental device. In this age, the females were mated, had a fully melanized tegument, were able to fly and to produce viable eggs. The volatiles of coffee, Coffea arabica L. var. Tupi, flowers were colected by aeration, analyzed in GC-EAD and GC-MS, and tested in olfactometer bioassays. The colonizing H. hampei females were attracted by the coffee flower volatiles. Of 50 compounds found in the natural extracts, seven were electrophysiologically actives to the insects. Of these seven, only methyl salicylate, neral and geranial could be identified, and the blend with their syntetic standards was the most atractive in the olfactometer bioassays. Taken together, these results bring new information on the bioecology and chemical ecology of the coffee berry borer, which may be used in the future by basic researchs or by those focused on the development of new strategies for the management of H. hampei in coffee farms.
3

Idade de fêmeas colonizadoras de Hypothenemus hampei (Ferrari) e sua resposta aos voláteis de flores de café, Coffea arabica L. / Age of colonizing Hypothenemus hampei (Ferrari) females and their response to volatiles of coffee, Coffea arabica L., flowers

Weliton Dias da Silva 15 April 2014 (has links)
A idade das fêmeas colonizadoras de Hypothenemus hampei (Ferrari) durante o abandonamento do hospedeiro, assim como sua resposta aos voláteis de flores de café, Coffea arabica L. var. Tupi, foram investigadas neste trabalho. Um dispositivo experimental que simulasse as condições de dentro do fruto de café e permitisse a observação da saída dos insetos foi utilizado para a determinação da idade das fêmeas colonizadoras. Em média, os besouros apresentaram 15 dias de idade no momento em que abandonaram o dispositivo experimental. Nesta idade as fêmeas estavam acasaladas, possuiam o tegumento totalmente melanizado, foram capazes de voar e produzir ovos viáveis. Os voláteis de flores de café, foram coletados por aeração, analisados por GC-EAD e GC-MS, e testados em bioensaios olfatométricos. As fêmeas colonizadoras de H. hampei foram atraídas pelos voláteis de flores de café. Dos 50 compostos encontrados nos extratos naturais, sete foram eletrofisiologicamente ativos aos insetos. Destes sete, somente metil salicilato, neral e geranial puderam ser identificados, e a mistura de seus padrões sintéticos foi a mais atrativa nos bioensaios olfatométricos. Tomados juntos, estes resultados trazem novas informações sobre a bioecologia e ecologia química da broca-do-café, as quais poderão ser usadas futuramente em pesquisas de base e naquelas focadas no desenvolvimento de novas estratégias de manejo para H. hampei em cafezais. / The age of Hypothenemus hampei (Ferrari) females during the host abandonment, as well as their response to coffee flower volatiles were determinated under laboratory conditions. A experimental device that simulated the conditions inside a coffee berry, and that allowed the observation the insects coming out was used to determinate the age of colonizing females. On average, the beetles were 15 d-old at the moment they abandoned the experimental device. In this age, the females were mated, had a fully melanized tegument, were able to fly and to produce viable eggs. The volatiles of coffee, Coffea arabica L. var. Tupi, flowers were colected by aeration, analyzed in GC-EAD and GC-MS, and tested in olfactometer bioassays. The colonizing H. hampei females were attracted by the coffee flower volatiles. Of 50 compounds found in the natural extracts, seven were electrophysiologically actives to the insects. Of these seven, only methyl salicylate, neral and geranial could be identified, and the blend with their syntetic standards was the most atractive in the olfactometer bioassays. Taken together, these results bring new information on the bioecology and chemical ecology of the coffee berry borer, which may be used in the future by basic researchs or by those focused on the development of new strategies for the management of H. hampei in coffee farms.
4

Estrutura da vegetação e sua relação com a diversidade, abundância e similaridade de coleópteros bioindicadores em diferentes sistemas vegetacionais, Piracicaba, SP / Structure of vegetation and your relationship whit diversity, abundance and similarity of coleopteros bioindicators in different systems vegetation, Piracicaba, SP

Rodríguez, Carla Andrea Sandoval 24 May 2016 (has links)
A Mata Atlântica é considerada um dos biomas mais importantes do mundo devido à sua alta biodiversidade e funções ecossistêmicas. Entretanto, encontra-se fragmentada em porções de pequenas dimensões esparsas em uma matriz predominantemente agrícola, composta principalmente por extensas pastagens e monoculturas. Desse modo, os sistemas agroflorestais por apresentarem uma estrutura diferenciada dos monocultivos e similar às condições naturais, podem ser utilizados como uma alternativa para o manejo e a conservação da biodiversidade nos remanescentes florestais. A fragmentação provoca modificações no ambiente que irão refletir na perda e no deslocamento da biodiversidade, estando os insetos entre os grupos mais afetados. Uma das formas de se avaliar o estado de conservação dos fragmentos e o impacto antrópico nos sistemas vegetacionais, é estudar a presença e distribuição de organismos bioindicadores. Dentre esses, os insetos ocupam posição de destaque. Os insetos da família Scarabaeidae e da subfamília Scolytinae são bons indicadores de distúrbios, pois são muito sensíveis ás mudanças ambientais. Neste trabalho hipotetisou-se que a presença desses insetos está relacionada com a estrutura da vegetação e as condições de vida proporcionadas pelas diferentes formas de uso-da-terra. O objetivo desta pesquisa foi avaliar a diversidade de espécies, o padrão de abundância e a similaridade entre as populações de coleópteros (Scarabaeidae e Scolytinae) em diferentes sistemas vegetacionais de diferentes estruturas: i) Fragmento de floresta estacional semidecidual dividido em três áreas: beira do rio, centro e borda; ii) Sistema Agroflorestal (SAF) (interface entre o fragmento e o pasto); iii) Pasto composto de Brachiaria decumbens (L.); iv) Monocultivo de café (Coffea arábica L.); v) Monocultivo de seringueira (Hevea brasiliensis Müell. Arg.); vi) SAF de café e seringueira - todos situados numa região de domínio anterior de floresta estacional semidecidual em Piracicaba-SP. Os sistemas foram caracterizados quanto à sua estrutura e condições micrometeorológicas. Os insetos foram coletados mensalmente entre agosto/2013 e julho/2014 utilizando-se dois tipos de armadilhas: Pitfall e etanol modelo ESALQ-84. Foram coletados 1.047 espécimes distribuídos em 21 espécies da família Scarabaeidae e 1.833 indivíduos de 38 espécies da subfamília Scolytinae. A maior quantidade de espécies de Scarabaeidae foi encontrada na borda do fragmento florestal, enquanto que a maior abundância ocorreu no fragmento florestal perto do rio. A subfamília Scolytinae apresentou a maior riqueza de espécies no sistema agroflorestal misto (borda) e a maior abundância no sistema agroflorestal café-seringueira. A abundância e riqueza de espécies da família Scarabaeidae foram correlacionadas positivamente com a temperatura do ar, temperatura e umidade do solo e a precipitação. Por outro lado, a abundância e a riqueza de espécies da subfamília Scolytinae apresentaram correlação negativa com a temperatura do ar e a temperatura e umidade do solo. Ambos os grupos de insetos apresentaram a maior abundância e riqueza de espécies nas áreas com estrutura vegetacional mais complexa, sendo influenciadas pelas condições microclimáticas dentro de cada local. / The Atlantic Forest is considered one of the most important biomes of the world due to its high biodiversity and ecosystem functions. However, it is fragmented into small portions sparse dimensions in a predominantly agricultural matrix, mainly composed of extensive pastures and monocultures. Fragmentation causes changes in the environment that will reflect the loss and displacement of biodiversity, with the insects among the most affected groups. One way to assess the conservation status of the fragments and the human impact on vegetation systems, is to study the presence and distribution of bioindicators. Among them, the insects occupy a prominent position. The insects of the family Scarabaeidae and Scolytinae subfamily are good indicators of disorders, as they are very sensitive to environmental changes. This work hypothesized the presence of these insects is related to the structure of the vegetation and the living conditions offered by different forms of use-of-land. The objective of this research is to evaluate the diversity of species, the abundance pattern and the similarity between the populations of Coleoptera (Scarabaeidae and Scolytinae) in different vegetation systems of different structures: i) Fragment of seasonal forest, divided into three areas: near to river, center and edge; ii) Agroforestry System (AFS) (interface between the fragment and pasture); iii) Pasture consists of Brachiaria decumbens (L.); iv) monocropping coffee (Coffea arabica L.); v) monocropping of rubber tree (Hevea brasiliensis Müell Arg); vi) AFS rubber with coffee - all situated in a former domain region of semideciduous forest in Piracicaba-SP. The systems were characterized for its structure and micrometeorological conditions. The insects were collected monthly between August / 2013 and July / 2014 using two types of traps: Pitfall and ethanol. Were collected 1.047 specimens distributed in 21 species of the Scarabaeidae family and 1.833 individuals of 38 species of the subfamily Scolytinae. The largest number of species of Scarabaeidae was found on the edge of the forest fragment, while the highest abundance occurred in the forest fragment near the river. The subfamily Scolytinae showed the greatest richness in the edge agroforestry system and the greatest abundance in agroforestry coffee-rubber system. The abundance and richness of species Scarabaeidae family were positively correlated with the air temperature, temperature and soil moisture and precipitation. On the other hand, the abundance and species richness of Scolytinae subfamily showed a negative correlation with the air temperature and the temperature and soil moisture. Both groups of insects had the highest abundance and species richness in areas with more complex vegetation structure, being influenced by the microclimate conditions in each location.
5

Estrutura da vegetação e sua relação com a diversidade, abundância e similaridade de coleópteros bioindicadores em diferentes sistemas vegetacionais, Piracicaba, SP / Structure of vegetation and your relationship whit diversity, abundance and similarity of coleopteros bioindicators in different systems vegetation, Piracicaba, SP

Carla Andrea Sandoval Rodríguez 24 May 2016 (has links)
A Mata Atlântica é considerada um dos biomas mais importantes do mundo devido à sua alta biodiversidade e funções ecossistêmicas. Entretanto, encontra-se fragmentada em porções de pequenas dimensões esparsas em uma matriz predominantemente agrícola, composta principalmente por extensas pastagens e monoculturas. Desse modo, os sistemas agroflorestais por apresentarem uma estrutura diferenciada dos monocultivos e similar às condições naturais, podem ser utilizados como uma alternativa para o manejo e a conservação da biodiversidade nos remanescentes florestais. A fragmentação provoca modificações no ambiente que irão refletir na perda e no deslocamento da biodiversidade, estando os insetos entre os grupos mais afetados. Uma das formas de se avaliar o estado de conservação dos fragmentos e o impacto antrópico nos sistemas vegetacionais, é estudar a presença e distribuição de organismos bioindicadores. Dentre esses, os insetos ocupam posição de destaque. Os insetos da família Scarabaeidae e da subfamília Scolytinae são bons indicadores de distúrbios, pois são muito sensíveis ás mudanças ambientais. Neste trabalho hipotetisou-se que a presença desses insetos está relacionada com a estrutura da vegetação e as condições de vida proporcionadas pelas diferentes formas de uso-da-terra. O objetivo desta pesquisa foi avaliar a diversidade de espécies, o padrão de abundância e a similaridade entre as populações de coleópteros (Scarabaeidae e Scolytinae) em diferentes sistemas vegetacionais de diferentes estruturas: i) Fragmento de floresta estacional semidecidual dividido em três áreas: beira do rio, centro e borda; ii) Sistema Agroflorestal (SAF) (interface entre o fragmento e o pasto); iii) Pasto composto de Brachiaria decumbens (L.); iv) Monocultivo de café (Coffea arábica L.); v) Monocultivo de seringueira (Hevea brasiliensis Müell. Arg.); vi) SAF de café e seringueira - todos situados numa região de domínio anterior de floresta estacional semidecidual em Piracicaba-SP. Os sistemas foram caracterizados quanto à sua estrutura e condições micrometeorológicas. Os insetos foram coletados mensalmente entre agosto/2013 e julho/2014 utilizando-se dois tipos de armadilhas: Pitfall e etanol modelo ESALQ-84. Foram coletados 1.047 espécimes distribuídos em 21 espécies da família Scarabaeidae e 1.833 indivíduos de 38 espécies da subfamília Scolytinae. A maior quantidade de espécies de Scarabaeidae foi encontrada na borda do fragmento florestal, enquanto que a maior abundância ocorreu no fragmento florestal perto do rio. A subfamília Scolytinae apresentou a maior riqueza de espécies no sistema agroflorestal misto (borda) e a maior abundância no sistema agroflorestal café-seringueira. A abundância e riqueza de espécies da família Scarabaeidae foram correlacionadas positivamente com a temperatura do ar, temperatura e umidade do solo e a precipitação. Por outro lado, a abundância e a riqueza de espécies da subfamília Scolytinae apresentaram correlação negativa com a temperatura do ar e a temperatura e umidade do solo. Ambos os grupos de insetos apresentaram a maior abundância e riqueza de espécies nas áreas com estrutura vegetacional mais complexa, sendo influenciadas pelas condições microclimáticas dentro de cada local. / The Atlantic Forest is considered one of the most important biomes of the world due to its high biodiversity and ecosystem functions. However, it is fragmented into small portions sparse dimensions in a predominantly agricultural matrix, mainly composed of extensive pastures and monocultures. Fragmentation causes changes in the environment that will reflect the loss and displacement of biodiversity, with the insects among the most affected groups. One way to assess the conservation status of the fragments and the human impact on vegetation systems, is to study the presence and distribution of bioindicators. Among them, the insects occupy a prominent position. The insects of the family Scarabaeidae and Scolytinae subfamily are good indicators of disorders, as they are very sensitive to environmental changes. This work hypothesized the presence of these insects is related to the structure of the vegetation and the living conditions offered by different forms of use-of-land. The objective of this research is to evaluate the diversity of species, the abundance pattern and the similarity between the populations of Coleoptera (Scarabaeidae and Scolytinae) in different vegetation systems of different structures: i) Fragment of seasonal forest, divided into three areas: near to river, center and edge; ii) Agroforestry System (AFS) (interface between the fragment and pasture); iii) Pasture consists of Brachiaria decumbens (L.); iv) monocropping coffee (Coffea arabica L.); v) monocropping of rubber tree (Hevea brasiliensis Müell Arg); vi) AFS rubber with coffee - all situated in a former domain region of semideciduous forest in Piracicaba-SP. The systems were characterized for its structure and micrometeorological conditions. The insects were collected monthly between August / 2013 and July / 2014 using two types of traps: Pitfall and ethanol. Were collected 1.047 specimens distributed in 21 species of the Scarabaeidae family and 1.833 individuals of 38 species of the subfamily Scolytinae. The largest number of species of Scarabaeidae was found on the edge of the forest fragment, while the highest abundance occurred in the forest fragment near the river. The subfamily Scolytinae showed the greatest richness in the edge agroforestry system and the greatest abundance in agroforestry coffee-rubber system. The abundance and richness of species Scarabaeidae family were positively correlated with the air temperature, temperature and soil moisture and precipitation. On the other hand, the abundance and species richness of Scolytinae subfamily showed a negative correlation with the air temperature and the temperature and soil moisture. Both groups of insects had the highest abundance and species richness in areas with more complex vegetation structure, being influenced by the microclimate conditions in each location.
6

Coleópteros das famílias bostrichidae e curculionidae (Scolytinae) associados a Banisteriopsis caapi (Spruce ex Grisebach) / Coleoptera families bostrichidae and curculionidae (Scolytinae) associated with Banisteriopsis caapi (Spruce Ex Grisebach) in Brazil

Pena, Rebeca Cristina 27 May 2013 (has links)
Made available in DSpace on 2016-06-02T18:57:47Z (GMT). No. of bitstreams: 1 5432.pdf: 4366223 bytes, checksum: cefd8da6f38998dd2acc2b32f85b8151 (MD5) Previous issue date: 2013-05-27 / A study on the population behavior of insects of the order Coleoptera was performed, more precisely with the families Curculionidae (Scolytinae) and Bostrichidae, in a plantation of Banisteriopsis caapi (Spruce ex Griseb.) Morton, a Malpighiaceae vine known as mariri. The liana, native from the Amazon region, is the component of the beverage Ayahuasca used by the indigenous tribes in the Amazon, and more recently by religious movements in Brazil and abroad. This plant is rich in β-carboline alkaloids, secondary compounds of interest in human medicine. The study was conducted in a plantation belonging to the Centro Espírita Beneficente União do Vegetal (UDV), in Campinas city, state of São Paulo, Brazil. The area consists of four sectors, two of which are in a more urbanized area, reforested with fruit trees. The other two sectors are in an area composed of forest fragments in different stages of succession. For this study, 32 flight intercept traps were used, eight in each sector, baited with ethanol, with weekly inspections during the period from February 12, 2010, to February 18, 2011. A total of 55 samples were collected, by means of which we determined the seasonal fluctuation of these beetles and attack patterns in the lianas. A total of 68 species were identified, where Scolytinae were the dominant group, with 90.2% of the species, followed by Bostrichidae with 9.4%, and Platypodinae, with 0.4%. No beetle was found alive inside the lianas during the study. The reforestated sectors, especially in the border region, were the most attacked by beetles. The attacks were concentrated in the lower part of the stems, and in lianas with larger diameter. The variety of liana named tucunacá was more attacked than the second variety, caupuri. A national survey in plantations of mariri was also performed, where beetles of the family Cerambicidae were also found. / O estudo foi realizado com populações de insetos da ordem Coleoptera, mais precisamente das famílias Curculionidae (Scolytinae) e Bostrichidae em um plantio de Banisteriopsis caapi (Spruce ex Griseb.) Morton, cipó pertencente à família Malpighiaceae, conhecido por mariri. O cipó, nativo da região amazônica, é um componente da bebida Ayahuasca, usada por tribos indígenas na Amazônia, e mais recentemente por movimentos religiosos no Brasil e exterior. Esta planta é rica em alcalóides β-carbolina, compostos secundários de interesse na medicina humana. O estudo foi desenvolvido em um cultivo do cipó pertencente ao Centro Espírita Beneficente União do Vegetal (UDV), localizado em Campinas/SP. A área é composta por quatro setores, dos quais dois ficam em uma zona mais urbanizada, reflorestada com frutíferas. Os outros dois setores ficam em uma área composta por fragmentos florestais em distintos estágios de regeneração. Para isso foram usadas 32 armadilhas de intercepção de vôo, oito em cada setor, modelo ESALQ-84, iscadas com etanol, com inspeções semanais durante o período de 12 de fevereiro de 2010 a 18 de fevereiro de 2011, totalizando 55 coletas, onde se determinou a flutuação sazonal desses besouros e padrões de ataque nos cipós. Obteve-se um total de 68 espécies, sendo Scolytinae a subfamília mais representativa, com 90,2% das espécies coletadas, seguida da família Bostrichidae com 9,4 % e Platypodinae com 0,4%. Nenhum besouro vivo foi encontrado dentro dos cipós durante a pesquisa. O setor de reflorestamento, especialmente na região de borda, foi o mais atacado pelos besouros. Os ataques se concentraram na parte mais baixa dos caules, e em cipós com maior diâmetro de haste. Dentre as duas variedades cultivadas, o cipó tucunacá foi mais atacado que o caupuri. Também foi feita uma pesquisa nacional em plantios de cipó mariri em outras regiões, onde foram encontrados besouros da família Cerambycidae.
7

A NON-NATIVE FOREST INVADER ALTERS FOREST STRUCTURE AND THE ASSOCIATED ARTHROPOD COMMUNITY

Savage, Matthew B. 01 January 2017 (has links)
The emerald ash borer (EAB, Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae) is a non-native wood boring beetle that is causing extensive ash (Fraxinus spp.) mortality in eastern North America, affecting both urban and wildland forests and drastically altering forest structure and composition. As EAB-induced ash mortality progresses, native arthropod associates of ash forests are impacted by the effects of rapid and broad scale tree mortality. These include loss of food source, increased canopy gap formation, alterations in litter inputs causing shifting temperature and moisture regimes on the forest floor, and significant accumulation of coarse woody debris. I assessed the sub-canopy arthropod community in five forests, all in different stages of the invasion process, from introduction through impact. Additionally, I assessed the ground level arthropod community in a post EAB-invaded forest with 100% mature ash mortality. Arthropod communities were assessed at the ordinal level, and with a focus on coleopterans, they were further classified to families and trophic guilds to analyze abundance, richness, and diversity. Due to their overwhelming abundance, I identified scolytines collected in the post EAB-invaded forest to species to see if the EAB-invasion was part of a greater invasional meltdown. My results indicate that the EAB-invasion in North America is affecting the native coleopteran communities associated with these forests.
8

The Effects of Spruce Beetle (Coleoptera: Curculionidae: Scolytinae) on Fuels and Fire in Intermountain Spruce-Fir Forests

Jorgensen, Carl Arik 01 May 2010 (has links)
In spruce-fir forests, there are many biotic and abiotic disturbances that can alter stand structure and composition. Many of these disturbances can produce high percentages of tree mortality at different scales. Spruce beetle has been considered a devastating disturbance agent, capable of creating high levels of mortality that will alter fuel complexes that may affect fire behavior. For comparison, stand data were gathered in endemic (near Loa and Moab, UT), epidemic (near Loa and Fairview, UT), and post-epidemic (near Salina and Loa, UT) condition classes of spruce beetle activity. Generally, fine fuels were higher during the epidemic and returned to background levels during post-epidemic conditions. Also, herbaceous and shrub components increase following outbreak situations with an initial pulse of herbaceous material during epidemics followed by the expansion of shrub material in post-epidemic areas. Fuel bed bulk depth, large diameter woody material, sound and rotten, and duff did not significantly differ between spruce beetle condition classes. Available live canopy fuel, canopy bulk density, and canopy base height were significantly reduced from endemic when compared to epidemic and post-epidemic condition classes. The fuel complex alterations resulted in changes to calculated surface and crown fire behavior. Crown base height decreased in post-epidemic classes, which allowed for easier crown fire initiation. Due to large gaps in canopy continuity, no active crown fire was initiated. In endemic situations, canopy bulk density was adequate to maintain active crown fire runs, but crown base height was too high to initiate crown fire. Surface fire, estimated from the custom fuel models following fuel complex alterations, showed that fireline intensity and rates of spread were greater in post-epidemic areas, but mostly due to reduced overstory sheltering. When custom fuel models were compared with similar mid-flame wind speeds, epidemic and post-epidemic fire behavior predictions were similar, indicating that reduced sheltering was more dominant than the influence of the fuels complex or solar radiation. When custom fuel models were compared with established fuel models, none predicted the same fire behavior outputs.
9

Enzyme Activity and Antimicrobial Screening of Ambrosiella grosmanniae

Onyenobi, Ebuka Isaiah 02 September 2021 (has links)
No description available.
10

Impact des coupes partielles sur l’activité de coléoptères phloeophages et xylophages en forêt boréale

Bélanger Morin, Mathieu 12 1900 (has links)
Ce projet de recherche évalue la réponse à court terme de coléoptères phloeophages et xylophages (Cerambycidae et Scolytinae) à différentes intensités de coupes partielles (0, 25 et 40% de la surface terrière prélevée) afin de déterminer la viabilité de cette méthode sylvicole en forêt boréale. Disposant de 12 parcelles expérimentales (4 répétitions pour chaque intensité de coupe) dans une sapinière à bouleau blanc située au sud de la forêt boréale (Québec, Canada), nous avons évalué l’abondance, la diversité ainsi que l’établissement (taux d’attaque) de ces deux groupes d’insectes, et ce dès la première année suivant la coupe. L’échantillonnage a été réalisé à l’aide de pièges à interception multidirectionnelle et de l’écorçage de sections de 3 espèces d’arbres exposées dans l’ensemble des parcelles. Nos résultats montrent une plus grande activité/abondance des deux taxons (abondance 5 à 6 fois plus élevée) ainsi qu’une composition en espèces différente et plus diversifiée dans les peuplements partiellement coupés (25 et 40%). De plus, la présence et la distribution d’espèces colonisant habituellement des hôtes affaiblis (e.g., Trypodendron lineatum, Rhagium inquisitor) – et pouvant donc réduire la valeur économique d’arbres résiduels – a été recensée et semble être favorisée entres autres par l’ouverture de la canopée et des blessures physiques faites aux arbres pendant les opérations sylvicoles. Par ailleurs, l’approche combinant différentes techniques d’échantillonnage a permis une meilleure compréhension des mécanismes de localisation/sélection d’hôte (variant en fonction de l’espèce), un aspect important de la dynamique des insectes pour l’évaluation des risques suite aux coupes forestières. Sur la base de cette étude à court terme, il ne semblerait pas y avoir de différence significative sur les risques pour le milieu quant à l’augmentation d’activité des Cerambycidae et Scolytinae entre les deux traitements de coupe appliqués. Il reste cependant indispensable de vérifier la validité de ces résultats sur une plus longue période afin d’établir des plans d’aménagement forestier durables pour la forêt boréale. / To evaluate the viability of partial cuts, short-term responses of phloeophagous and xylophagous beetles (Cerambycidae and Scolytinae) following different partial cut treatments (0, 25 and 40% of basal area cut) were determined in a balsam fir–white birch boreal forest in Quebec, Canada. Each treatment was replicated 4 times totaling 12 experimental stands. The summer following treatments, abundance and diversity of targeted beetle groups along with their establishment (attack rates) in partially cut stands were assessed with passive flight- interception traps and bark dissection of exposed, freshly cut boles from three tree species. Greater activity/abundance from both taxa were detected (abundance 5 to 6 times larger) along with a different and more diversified species composition in partially cut stands (25 and 40%). The presence and distribution of species that usually colonize weakened host trees (e.g., Trypodendron lineatum, Rhagium inquisitor) – and can thus reduce stands economic value for future harvest operations – were influenced by canopy openness and injuries on residual trees made during silvicultural operations. Furthermore, combining diverse sampling techniques allowed us to observe different host-selection patterns (random landing vs. primary attraction) given our multi-scale experimental approach, which we found to vary between insect species. Understanding these mechanisms for such beetle groups are important to evaluate stand vulnerability following partial cuts and predict impacts and risks in a given environment. While the 40% partial cuts remove additional wood volume, we found no significant increase in beetle activity between the 25 and 40% treatment. Though partial cuts render treated stands more vulnerable to greater Cerambycidae and Scolytinae attacks, further studies must be done to confirm this trend in longer term if proper boreal forest management plans are to be drawn.

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