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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.
31

Greenhouse gas emissions from grassland pasture fertilized with liquid hog manure

Tremorin, Denis Gerald 17 November 2009 (has links)
A study was conducted in 2004 and 2005 to determine the effect of liquid hog manure fertilization on greenhouse gas emissions from the surface of a grassland pasture in south-eastern Manitoba. The objectives of this research were to determine the effects of manure application, itstiming and soil moisture on greenhouse gas emissions from pasture soil, cattle dung and urine patches. Nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) emissions were determined from grassland soil surface, and from cattle dung and artificial urine patches. Liquid hog manure treatments were no manure (Control); 153 kg ha-1 of available-nitrogen (N) (two year average) in spring (Spring); and 149 kg ha-1 as half-rate applications in fall and spring (Split). Four field experiments were conducted on grassland plots. The static-vented chamber technique was used to estimate gas emission rates. Two of the experiments focused on the effects of manure application timing and soil moisture on greenhouse gas emissions from the grassland soil surface. The other two experiments focused on the effects of manure application and soil moisture on greenhouse gas emissions from cattle dung and artificial urine patches. Fresh cattle dung was collected from steers grazing adjacent pastures receiving the same three manure treatments. Artificial cattle urine treatments were generated by converting blood urea concentrations of the steers into urine-N concentrations. Manure application increased (P≤0.01) cumulative N2O emissions from the grassland soil surface with Control, Split and Spring treatments averaging 7, 43 and 120 mg N2O-N m-2, respectively. Of the two manure treatments, the Spring treatment emitted higher (P≤0.10) N2O emissions than the Split treatment. Soil moisture was a major factor influencing the quantity and type of greenhouse gas emissions, with saturated areas emitting CH4 during warm periods, whereas drier areas emitted N2O. Nitrous oxide emissions from these dry areas were higher in manure-treated plots. Spring application increased root density by 45% in the top 5 cm of soil compared to the Control. An increase in soil organic carbon with root density may offset any increase in greenhouse gas emissions caused by manure treatment. Cattle dung from Split and Spring treatments had higher cumulative N2O emissions (30 and 82 mg N2O-N m-2, respectively) compared to dung from Control pastures (6 mg N2O-N m-2) over two study years. Dung from the Spring treatment emitted more N2O (P≤0.01) than the other two treatments. All cattle dung patches emitted CH4 after deposition though unaffected by manure treatment. Artificial urine having highest N concentration had greater (P≤0.05) cumulative N2O emissions (690 mg N2O-N m-2) than urine with the lowest N concentration (170 mg N2O-N m-2). Drier soil locations emitted more N2O from cattle dung and artificial urine patches than wetter areas. This study demonstrated that Split application of liquid hog manure to grassland emitted less N2O than a complete application in spring. Moisture greatly affected the location of N2O and CH4 emissions. Drier areas emitted more N2O than wetter ones. Particularly, the findings indicate a need to assess grassland on periodically saturated soils as sources rather than sinks for CH4. Application of manure increased greenhouse gas emissions from cattle dung and urine patches with urine potentially having the greatest impact because of their higher emissions of N2O. An increase in root growth seems to offset greenhouse gas emissions from manure application.
32

Invasão e estabelecimento de Digitonthophagus gazella (Fabricius) (Coleoptera: scarabaeidae) em fragmento de transição cerrado-mata atlântica / Invasion and establishment of digitonthophagus gazella (Fabricius) (Coleoptera: scarabaeidae) in transition fragment atlantic forest

Angotti, Marina Acero 17 March 2014 (has links)
Made available in DSpace on 2016-06-02T18:57:49Z (GMT). No. of bitstreams: 1 5843.pdf: 20411510 bytes, checksum: 6c8a32aab0699c1288fb33bf02ffdf15 (MD5) Previous issue date: 2014-03-17 / Financiadora de Estudos e Projetos / Digitonthophagus gazella is known worldwide because it has been introduced in tropical and subtropical regions of several countries. The aim of this introduction was to assist in the removal of dung pats in pasture areas and to aid in the biological control of flies of veterinary importance. Thus, although D. gazella has a preference for open and sunny habitats and herbaceous vegetation, there is evidence that it apparently has been adapting to closed-canopy areas. Therefore, this study aimed at evaluating the ability of D. gazella to develop in a forest environment. The study was conducted in 2012 and 2013 in the Farm of UNESP - Ilha Solteira in Mato Grosso do Sul, Brazil. To evaluate the presence of D. gazella in the forest were used pitfall traps and to verify its capability of develop in this habitat couples of this species were kept in pasture and forest fragment in the absence and presence of competitors. The results indicate that D. gazella is able to enter the forest fragment, but at short distances from the edge. Additionally, D. gazella was not able to develop and establishment in the forest fragment. / A espécie Digitonthophagus gazella é conhecida mundialmente pelo fato de ter sido introduzida em regiões tropicais e subtropicais de vários países. O objetivo dessas introduções foi o de auxiliar na remoção de massas fecais em áreas de pastagem e no controle biológico de moscas de importância veterinária. D. gazella apresenta preferência por habitats abertos e ensolarados e de vegetação herbácea, porém há indícios de que esta vem se adaptando a áreas fechadas. Com isso, este estudo objetivou avaliar a capacidade de D. gazella em se desenvolver em ambiente florestal. O estudo foi realizado nos anos de 2012 e 2013 na Fazenda de Pesquisa e Extensão da UNESP - campus de Ilha Solteira, em Selvíria/MS. Para avaliar a presença de D. gazella na mata foram utilizadas armadilhas pitfall e para verificar a capacidade de desenvolvimento um casal da referida espécie foi mantido no pasto e no fragmento florestal na ausência e presença de competidores. Os resultados indicam que D. gazella é capaz de entrar no fragmento florestal, porém a curtas distâncias da borda. E que de forma geral os indivíduos desta espécie não são capazes de se desenvolverem e se estabelecerem no fragmento florestal.
33

Determinação de horário de vôo e fatores que o influenciam, em scarabaeidae coprófagos diurnos e noturnos em Selvíria/MS

Mesquita Filho, Walter [UNESP] 28 August 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-28Bitstream added on 2014-06-13T21:00:05Z : No. of bitstreams: 1 mesquitafilho_w_me_ilha.pdf: 1865564 bytes, checksum: 2d2aed8cb98f05de9541e5ae01637ab5 (MD5) / A atividade de vôo em besouros coprófagos é de extrema importância pois é neste momento em que estes encontram seu alimento, a massa fecal, através de odores liberados por estas. O horário de vôo é importante devido à grande competição que ocorre entre as espécies. Tanto fatores abióticos quanto bióticos influenciam essa atividade. O objetivo deste trabalho foi determinar o horário de vôo de e a influência de ambos os fatores na regulação deste, em área de fragmento de Mata Atlântica e pastagem de Brachiaria decumbens, na Fazenda da UNESP, em Selvíria/MS. Utilizou-se de armadilhas pitfall em ambas as áreas, iscadas com massa fecal bovina, colocadas às 7:00 h e às 18:00 h, e luminosa, localizada na área de pastagem. A coleta dos besouros coprófagos foi feita a cada 20 min, durante 24 horas, uma vez por semana, e dos dados climáticos a cada 10 min. De outubro de 2006 a março de 2007 foram coletados 14205 indivíduos, sendo 11737 em luminosa, 1635 em pitfall no pasto e 835 em pitfall na mata e identificando-se 61 espécies de besouros coprófagos. Em relação aos tipos de armadilhas utilizadas, luminosa foi mais eficiente na captura de espécies endocoprídeas que a armadilha pitfall. Em condições de alta densidade populacional a armadilha luminosa expressou de forma similar às armadilhas pitfall os padrões de vôo das espécies paracoprídeas noturnas, porém quando em baixa densidade, em função do maior número de repetições, as armadilhas pitfall foram melhores. Quanto ao período de vôo, a maioria das espécies coletadas foi de hábito noturno, este talvez determinado pelas altas temperaturas do ar reinantes durante o período diurno, das quais estas procuram escapar, em especial aquelas paracoprídeas. A intensidade luminosa foi a variável meteorológica responsável pelo início do vôo tanto em espécies noturnas endocoprídeas... / Flight activity in dung beetles is of extreme importance, for this is the time when they find their food, the dung pad, by volatiles released by them. The time of flight is important due to a high degree of competition that occurs among dung beetle species. Both abiotic and biotic factors influence this activity. The objective of this research was to determine the time of flight of dung beetles and the influence of both abiotic/biotic factors on its regulation, in a fragment of Atlantic forest and Brachiaria decumbens pasture, at the UNESP Farm, located in Selvíria, state of Mato Grosso do Sul, Brazil. Pitfall traps were used in both areas, baited with fresh bovine dung pads, at 7:00 AM and replaced by fresh ones again at 6:00 PM, and also a black light flight intercept trap in the pasture area. Trapped beetles were collected every 20 min for 24 hours straight, once a week, while climatic data were gathered every 10 min, from October 2006 until March 2007. A total of 14,205 specimens were trapped, 11,737 in the flight trap, while in pitfall traps 1,635 and 835 beetles were trapped in the pasture and fragment areas, respectively, corresponding to 61 different species. The flight trap was more efficient in trapping endocoprid species. When in high population, the flight pattern of nocturnal paracoprid beetles was equally well expressed by both trap types, while in low densities pitfall traps performed better, probably due to a larger number of replications. Most trapped species proved to be nocturnal, perhaps due to the high daily air temperatures, from which they could be avoiding, especially so for the paracoprid species. The light intensity was the meteorological factor responsible for flight initiation, in both endocoprid and paracoprid species. The flight in nocturnal endocoprid species was of short duration (ca. 80 min), probably because of their greater inability of regulating their... (Complete abstract click electronic access below)
34

Porovnání energetické, pracovní a materiálové náročnosti různých způsobů odklizu a skladování výkalů skotu. / Comparison of energetic, working and material demands of various methods of clearance and storage of cattle excrement

MÍČEK, Michal January 2007 (has links)
Target of this diploma work was with one another confront energy, material and working heftiness of clearance excrement cattle in cattle house technologies and subsequently storage and application excrement cattle.
35

Revisão taxonômica e análise filogenética do subgênero Malagoniella (Malagoniella) Martínez, 1961 (Coleoptera: Scarabeidae: Scarabeinae)

COSTA, Fábio Correia 19 February 2015 (has links)
Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-03-23T17:53:25Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertacao_Fabio Correia Costa.pdf: 5363839 bytes, checksum: 5a61b945fc8ff2be76123636ab5e5fff (MD5) / Made available in DSpace on 2016-03-23T17:53:25Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertacao_Fabio Correia Costa.pdf: 5363839 bytes, checksum: 5a61b945fc8ff2be76123636ab5e5fff (MD5) Previous issue date: 2015-02-19 / CNPq / O presente trabalho tem como objetivo revisar o subgênero Malagoniella e buscar uma hipótese da monofilia do grupo, assim como do relacionamento filogenético entre suas espécies. O primeiro capítulo aborda a análise filogenética do subgênero, para a qual foi utilizado o programa TNT, versão 1.1. Dichotomius bicuspis foi o grupo externo terminal utilizado para o enraizamento das análises. Para a árvore gerada (min. length = 0) foram calculados os valores de índice de consistência (IC) e índice de retenção (IR), e, para verificar o apoio dos clados, uma análise de “Bremer”, e “Bootstrap” como indicador de conflito entre os caracteres foram realizados. O subgênero Malagoniella foi considerado monofilético, sustentado por duas sinapomorfias e consta, a partir dos resultados alcançados, de 11 espécies e subespécies. O segundo capítulo inclui a revisão do subgênero, incluindo as redescrições em Malagoniella (Malagoniella) e novo status taxonômico para este, assim, como para as espécies/subespécies. Além de dados de distribuição geográfica e descrição de um novo táxon, que até o momento, é endêmico para o território brasileiro. Ainda, foram incluídas chave de identificação e a designação de neótipo e novo status taxonômico para as subespécies de M. astyanax. / This study presents aims to review the subgenus Malagoniella (Malagoniella) and search a hypothesis about the monophyly of the group, as well as the phylogenetic relationships between yours species. The Chapter one explains about the phylogenetic analyze of subgenus, that was performed on TNT program version 1.1. Dichotomius bicuspis was the terminals outgroup used to rootedness the analyzes. The generated tree (min. length = 0), were calculated consistency index (CI) and retention index (RI). In order to verify the support of the clades, analysis of “Bremer”, and “Bootstrap”, as conflict indicator between characters were done. The subgenus Malagoniella was considered monophyletic, supported by two synapomorphies and included 11 species and subspecies from the results achieved. The Chapter two, includes a review the subgenus, including redescriptions of Malagoniella (Malagoniella) and new taxonomic status to species and subspecies. Furthermore, geographic distribution data and a description of new taxon. Until this moment, this taxon is endemic at Brazilian territory. Moreover, it was included a key to identification and neotype designation to M. astyanax.
36

Re-pair for Trees

Mennicke, Roy 20 October 2017 (has links)
We introduce a new linear time compression algorithm, called 'Repair for Trees', which compresses ordered trees over a ranked alphabet using linear straight-line context-free tree grammars. Such grammars generalize straight-line context-free string grammars and allow basic tree operations, like traversal along edges, to be executed without prior decompression. Our algorithm can be considered as a generalization of the 'Re-pair' algorithm developed by N. Jesper Larsson and Alistair Moffat in 2000. The latter algorithm is a dictionary-based compression algorithm for strings. We also introduce a succinct coding which is specialized in further compressing the grammars generated by our algorithm. Thisis accomplished without loosing the ability do directly execute queries on this compressed representation of the input tree. Finally, we compare the grammars and output files generated by a prototype of the Re-pair for Trees algorithm with those of similar compression algorithms. The obtained results show that that our algorithm outperforms its competitors in terms of compression ratio, runtime and memory usage.
37

Effects of different pastures management on dung beetle communities in a sub-mountainous landscape of central Italy: a multicomponent biodiversity and ecological process analysis

Tonelli, Mattia 24 February 2017 (has links)
Los escarabajos coprófagos (Coleoptera: Scarabaeoidea) son un grupo de insectos muy importante en términos de diversidad y biomasa en los pastos de la cuenca del Mediterráneo. A pesar de su importancia ecológica, los escarabajos coprófagos están amenazados por varios factores, entre los cuales se destacan los cambios en el manejo de la ganadería tradicional. El objetivo general de esta tesis fue evaluar los efectos del abandono de la ganadería, su extensificación y uso histórico de productos médico veterinarios sobre las comunidades de escarabajos coprófagos usando medidas de biodiversidad y cuantificando la capacidad de remoción de estiércol en un paisaje sub-montano de la provincia de Pesaro-Urbino (Italia). En este trabajo se colectaron un total de 156 936 individuos, pertenecientes a 58 especies de escarabajos coprófagos. Los resultados de este trabajo sugieren que el uso histórico de productos médico veterinarios tiene un impacto negativo y ubiquitario sobre todas las especies de la comunidad de estudio, llevando a un empobrecimiento de los ensambles y a una pérdida de abundancia y biomasa. No obstante se ha registrado el mantenimiento de la estructura de la comunidad. Estos resultados son corroborados igualmente cuando nos enfocamos en la diversidad funcional. En efecto, el uso histórico de productos médico veterinarios lleva a una pérdida en el número de roles funcionales dentro de la comunidad, sin embargo las abundancias se encuentran repartidas equitativamente dentro de cada nicho funcional. Todos estos efectos sobre la comunidad de escarabajos coprófagos debido al uso de productos médico veterinarios, al final quedan reflejados en una pérdida del 70% en la capacidad de remoción de estiércol, comparados con áreas donde estos productos no son aplicados. La extensificación de la ganadería está representada por áreas que tienen una intensidad de pastoreo muy baja, las cuales pueden ser consideradas como la primera etapa hacia el abandono completo. En este sentido, los resultados de este trabajo demuestran como una simple reducción de la carga ganadera lleva a efectos negativos sobre las comunidades de escarabajos coprófagos, registrando una disminución en la diversidad alpha y en el número de especies indicadoras. Esta disminución en la cantidad de recurso trófico tiene implicaciones sobre la composición de la comunidad, favoreciendo especies oportunistas cuya biología le permite evitar la competencia, como por ejemplo; especies cleptoparásitas o especies cuyas larvas tienen un comportamiento saprófago. Este “efecto filtro” (filter effect) debido a la disminución de la cantidad trófica, está confirmado por los resultados de diversidad funcional, en los cuales se registró una disminución en el número de nichos funcionales y una fuerte redundancia por la presencia de nichos funcionales muy similares entre ellos. Los efectos sobre la comunidad de escarabajos coprófagos en los sitios con baja carga ganadera reflejan finalmente una pérdida en la capacidad de enterramiento del estiércol del 30-40% respecto a las comunidades en áreas con una mayor carga ganadera. Los resultados de este trabajo muestran que en las áreas con abandono total de la ganadería se observó una disminución en el número de especies, en la abundancia y biomasa total, en el número de especies indicadoras, en la abundancia de las especies de gran tamaño y en las especies que no tienen un comportamiento de nidificación durante el periodo reproductivo. Sin embargo, el mantenimiento de una comunidad bien estructurada, subraya la importancia de dos factores locales: el excremento de la fauna silvestre y la mayor complejidad del hábitat debido a un proceso de invasión de árboles en el pasto. Este último factor es probablemente responsable de la presencia de especies indicadoras típicas de hábitats más cerrados como los bosques o matorrales. En cuanto a los resultados de diversidad funcional, estos confirman la interpretación del “efecto filtro” debido a la disminución en la cantidad de recurso trófico. En efecto, estos resultados muestran una unicidad funcional significativa en esta comunidad como consecuencia del fuerte cambio composicional que el abandono de la ganadería ha implicado, a pesar de una disminución en el número de nichos funcionales y en el mantenimiento de una buena estructura funcional. Así mismo, se registró una disminución en la capacidad de enterramiento del estiércol entre 27% y 47% respecto a las áreas con baja carga ganadera y con carga moderada por todos estos cambios cuali y cuantitativos en la comunidad de escarabajos coprófagos de los sitios abandonados. Se propone la ganadería ecológica como forma correcta de gestión de los pastos, la cual permitiría mantener un nivel de carga moderado, así como el control en uso de compuestos médico veterinarios.
38

Screening the gut of dung beetles and dung beetle larvae for hemi-cellulolytic fungi and enzymes for application in the biofuel industry

Makulana, Livhuwani January 2021 (has links)
Thesis (Ph.D. (Microbiology)) -- University of Limpopo, 2021 / Biofuel production from lignocellulose material is an attractive alternative to fossil fuel. The use of lignocellulose material for biofuel production is imperative because of the numerous advantages that it offers. Biofuel is environmentally friendly and in developing countries such as South Africa, it has the potential to reduce the use of imported fuel and create jobs. Currently, several constraints are affecting the implementation of biofuel. One of the constraints is the cost-effectiveness and the efficiency of the enzymes involved in the enzymatic degradation of lignocellulose polymers to monomers, which can further be fermented to bioethanol. The potential way to reduce enzymatic degradation cost could be by supplementing the fungal enzymes with accessory enzymes such as endo-xylanase. The enzyme production cost is also dependent on the carbon source used. Lignocellulose materials that are regarded as waste must be assed for their use as enzyme inducer carbon sources and as biomass for biofuel production. This is a potential route that will reduce enzyme and biofuel production costs. Biofuel production cost can further be reduced by finding a yeast that can ferment xylose and ferment in the presence of inhibitors released during lignocellulose pretreatment. This study sought to tackle the enzymatic hydrolysis constraints and also search for xylose-fermenting yeast by exploring the gut microbiota of dung beetle. The gut of the dung beetle has recently received great attention since it is proposed to be a bioreactor for lignocellulolytic microorganisms that can be used in biofuel applications. This is because dung beetles feed on the dung of herbivorous animals and the dung is composed of 80% undigested plant material. In this study the guts of four Scarabaeidae dung beetles Kheper nigroanaeus Boheman, Heteronitis castelnaui, Pachylomerus femoralis, Anachalcos convexus and dung beetle larvae, Euoniticellus intermedius were screened for hemicellulolytic fungi and xylose-fermenting yeast. Hundred and thirty-two yeast isolates and two-hundred and twenty-two filamentous fungi were isolated and identified using ITS and D1/D2 regions. The yeast isolates were assigned to 8 genera and 18 species, Trichosporon was the most dominant genus while Candida tropicalis was the most dominant specie. Some of the yeast isolates were identified as uncultured fungi. This yeast must be characterised to be certain if they are novel species. The fungal isolates were assigned to 12 genera and 25 species, Aspergillus was the most dominant genus while Hypocrea lixii was the most dominant specie. The yeast isolated could assimilate xylose and could grow at a maximum temperature of 40 °C. Furthermore, these yeast isolates could also grow in the presence of 3 g/L acetic acid. Most of the fungal isolates had xylanolytic activity. The phylogenetic analysis revealed close genetic relatedness between isolates from the different dung beetle species and dung beetle larvae. The profile of the fungal genera was similar in the different dung beetles. Both guts and the larvae had Aspergillus, Hypocrea, Trichoderma, Talaromyces and Penicillium. The filamentous fungi that showed good xylanolytic activity were further screened for their ability to produce xylanase enzyme using thatch grass as an inductive carbon source. Thatch grass was selected in this study since it is in-house plant-based biomass. Thatch grass is abundantly available in South Africa; it is used for animal grazing but the more it grows it loses its nutritional content. Once it reaches this stage, it is no longer used and most of it is burnt. The fire from burning grass contains higher levels of nitrogen-containing chemicals that pollute the environment. Its compositional analysis (cellulose 46%, hemicellulose 27% and lignin 10%) also attributed to its selection as potential inductive carbon and attractive lignocellulose biomass for biofuel production. The higher xylanase activity of 283.43, 270 and 287.03 nkat/ml were observed from Aspergillus fumigatus L1XYL9 (Euoniticellus intermedius larvae), Hypocrea lixii AB2A3 and Neosartotya sp AB2XYL20 (Anachalcos convexus), respectively. This was achieved when acid pretreated thatch grass was used as an inductive carbon source. Aspergillus fumigatus L1XYL9 (Euoniticellus intermedius larvae), Hypocrea lixii AB2A3 and Neosartotya sp AB2XYL20 (Anachalcos convexus) showed xylanase activity of 393,22, 313,06 and 200 nkat/ml when grown on synthetic xylan. Neosartotya sp AB2XYL20 showed higher xylanase activity on thatch grass. The suitable production process for xylanase enzyme on acid pretreated thatch grass was assessed by conducting a comparative study on solid-state and submerged fermentation using L1XYL9 (Euoniticellus intermedius larvae), Hypocrea lixii AB2A3 and Neosartotya sp AB2XYL20 (Anachalcos convexus) as the best xylanase producer on acid pretreated thatch grass. The strain showed better xylanase activity when submerged fermentation was used. In this study, Hypocrea lixii AB2A3 was selected for further studies since it was the most dominant species and also showed good xylanase activity. Thatch grass was pretreated differently to evaluate the suitable chemical for pretreating thatch grass. Thatch grass was pretreated with dilute sulphuric acid 1.2% and maintained the pH of 5.5 by using sodium hydroxide while another batch was pretreated the same way and was washed with distilled water till pH of 5.5. The other batch was then pretreated with ammonium solution and was also washed with distilled water to maintain a pH of 5.5. The above-mentioned pretreated thatch grass was tested as an inductive carbon source as well as untreated thatch grass. The xylanase activity was determined to assess a good inductive carbon. All the thatch grass pretreated and washed with distilled water showed very low xylanase activity. The untreated thatch grass resulted in lower xylanase activity as compared to xylanase activity achieved when pretreated thatch grass was used. Parameters such as agitation speed and initial inoculum size were also assessed during xylanase production by Hypocrea lixii AB2A3 on acid pretreated thatch grass. Xylanase activity increased from 525 nkat/ml (Inoculum size 2×106 spore/ml and agitation speed 150 rpm) to 584.8 nkat/ml (Inoculum size 2×106 spore/ml and agitation speed 200 rpm). The crude xylanase from Hypocrea lixii AB2A3 was used to hydrolyse acid pretreated thatch grass. This resultant in xylose yield of 138 mg/g of substrate and glucose yield of 49 mg/g of substrate. Crude xylanase was mixed with commercial celluclast™. This enzyme mixture resulted in a xylose yield of 128 mg/g substrate and a glucose yield of 549 mg/g of substrate. The results obtained in this study show that indeed gut of the dung beetles and dung beetle larvae are a rich source of microorganisms that can play an important role in biofuel application and remediating the environment by degrading plant-based biomass regarded as waste into valuable products. It is imperative to evaluate the gut microbiota of dung beetles from different regions in South Africa for their application in the biofuel industry to reinforce its implementation. Thatch grass is a potential inductive carbon and lignocellulose biomass for biofuel production. / NRF (National Research Foundation)
39

Spillningslevande bladhorningar (Scarabaeoidea) kring Varbergs kustslätt, en återinventering

Malmström, Klara January 2022 (has links)
Dyngbaggar tillhör en av de mest studerade insektsgrupperna inom ekologiska undersökningar på grund av deras förekomst i ett spritt förekommande habitat som spillning. Förekomsten av denna grupp skalbaggar har präglats av det kulturhistoriska brukandet av marker som under en längre tid hävdats genom bete med domesticerade djur på marker av olika karaktär. Idag är dessa habitat sparsamt förekommande i ett landskap präglat av fragmentation och förändrad markanvändning vilket ställer betesberoende populationers överlevnad på prov. För att kartlägga vilken påverkan dessa landskapsförändringar har på insektsfaunan är långsiktig miljöövervakning av stor vikt för att bromsa oåterkalleliga förluster. Syftet med den här studien är att undersöka dyngbaggefaunans artsammansättning och individtäthet under vår-och högsommar på tidigare inventerade lokaler 1997 i utkanten av Varberg i mellersta Hallands län. Sedan 1997 har den totala diversiteten ökat med fem tillkomna arter på de fem undersökta lokalerna där ingen art har försvunnit helt. Det fanns ingen statistisk skillnad mellan art- och individantal men artsammansättningen skilde sig på lokalerna där vissa har ökat i antal, tillkommit eller blivit färre. Detta visar på en potentiellt positiv trend men fortgående övervakning krävs för att detta skall bekräftas. De förändringar som har skett i betesmarkernas lokala klimat avspeglar förändringar i artsammansättningen på grund av att betestrycket blivit lägre, marker har betats över längre tid samt restaureringar som har lett till en positiv utveckling. Lokalerna har blivit mer distinkta och skiljer sig både från varandra och hur de såg ut 1997 vilket skapat en större artrikedom. För en gynnsam bevarandestatus krävs en variation av mikroklimat för att även de habitat-specifika arterna ska ha möjlighet att etablera sig.
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Rapid divergence of local populations with different color forms in the dung beetle Phelotrupes auratus revealed by population genomics analyses / 集団ゲノム解析で明らかになった食糞性甲虫オオセンチコガネにおける異なる色彩型の地域集団の急速な分化

Araki, Yoshifumi 23 January 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24310号 / 理博第4880号 / 新制||理||1698(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 曽田 貞滋, 准教授 渡辺 勝敏, 教授 中務 真人 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

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