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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.
51

Dispers?o de sementes de leguminosas forrageiras tropicais atrav?s das fezes de bovinos / Dispersal, germination and persistence of tropical forage legumes through bovine feces.

Silva, Tatiana Oliveira da 04 September 2008 (has links)
Submitted by Leticia Schettini (leticia@ufrrj.br) on 2016-10-10T14:09:10Z No. of bitstreams: 1 2008 - Tatiana Oliveira da Silva.pdf: 1137658 bytes, checksum: 31af0cd49ed243269ee071f1dbf32c78 (MD5) / Made available in DSpace on 2016-10-10T14:09:10Z (GMT). No. of bitstreams: 1 2008 - Tatiana Oliveira da Silva.pdf: 1137658 bytes, checksum: 31af0cd49ed243269ee071f1dbf32c78 (MD5) Previous issue date: 2008-09-04 / Legumes have some characteristics which make them able to improve pasture productivity, since they act as green manure and prevent soil erosion by weather agents. They contribute, furthermore, to maintaining or increasing soil organic matter level, since they draw carbon and fix atmospheric Nitrogen, so mobilize and recycle nutrients, increasing microbiological soil activity. Considering the useful potential of these forage plants the seed dispersal of five legume species (Pueraria phaseoloides, Neonotonia wightii, Calopogonium mucunoides, Macrotyloma axillare and Stylosanthes cv. Mineir?o) through bovine feces in an established pasture of B. decumbens was studied in two trials. In the first one seeds mixed with concentrate were offered in the late afternoon to five crossbred (Holsten-Zebu) heifers weighing 250 kg. This experiment was carried out in a crop-pasture rotation system with five paddocks occupied for 4 days. Field evaluation were made from 12 to 30 hrs after seed ingestion, consisting in marking with sticks of different colors the sites of animal droppings in order to discriminate legume species. After 73 days of pasture vacancy was made the first evaluation in order to set the number of sprouts in the research field and Pueraria phaseoloides (puero) showed the best results, followed by Macrotyloma axillare (archer) and Calopogonium mucunoides (calopo). We accessed, in addition, the drought resistance after 266 days of pasture closure counting the survival legume plants in the pasture. The best performance for plant survival after dry season was observed in archer, followed by calopo. Concerning germination after the dry season of seeding made at the beginning of the experiment, best results were found by perennial soybean, despite its low results during the dry season. A second experiment was conducted using only archer seeds as they showed the best results concerning drought persistence. Five heifers were fed with 40 g of archer seeds; the animals were kept grazing for four days at the paddock in the crop-pasture system. At the first evaluation of this experiment we observed 215 archer plants in the research field. At the second evaluation the botanical composition analysis was made revealing the presence of 6,4% of the research area covered by archer plants (global mean of 380 plants). / As leguminosas possuem algumas caracter?sticas que contribuem para a produtividade do pasto, assim como a aduba??o verde, protegendo o solo dos agentes clim?ticos. Al?m disso, as leguminosas seq?estram o carbono e fixam o nitrog?nio atmosf?rico e, assim, apresentam potencial para manter ou elevar o teor de mat?ria org?nica, mobilizar e reciclar nutrientes e favorecer a atividade biol?gica do solo. Levando em considera??o o potencial ben?fico destas planta forrageiras objetivou-se avaliar a dispers?o de sementes de cinco leguminosas forrageiras tropicais (Pueraria phaseoloides, Neonotonia wightii, Calopogonium mucunoides, Macrotyloma axillare e Stylosanthes cv. Mineir?o) atrav?s das fezes de bovinos em pastagem j? estabelecida de Brachiaria decumbens. O primeiro experimento foi realizado em sistema de lota??o rotacionada, com 5 piquetes e 2 dias de ocupa??o. As sementes das cinco leguminosas foram oferecidas a cinco novilhas mesti?as (holand?s x zebu), pesando m?dia de 250 kg, misturadas ao concentrado no fim da tarde. Entre 12 e 30 horas ap?s a ingest?o das sementes era feita uma avalia??o a campo que consistia na marca??o com bambus de diversas cores do local das deje??es dos animais, diferenciando as esp?cies. Ap?s 73 dias de descanso foi realizada a primeira avalia??o quanto ao n?mero de plantas germinadas na ?rea experimental, sendo o Pueraria phaseoloides (kudzu tropical) a esp?cie que apresentou o melhor resultado, seguido pelo Macrotiloma axillare (macrotiloma) e Calopogonium mucunoides (calopog?nio). Ainda foi avaliada a persist?ncia ? seca, ap?s 266 dias de veda??o da pastagem, contabilizando o n?mero de plantas presentes no pasto. O melhor desempenho quanto ao n?mero m?dio de plantas ap?s a seca foi alcan?ado pelo macrotiloma, sendo seguida pelo calopog?nio. Quanto ? germina??o ap?s o per?odo de seca, das sementes implantadas no in?cio do experimento, o melhor resultado foi obtido pela soja perene, apesar da sua baixa contribui??o no per?odo de seca. O segundo experimento foi realizado apenas com sementes de macrotiloma devido ao bom resultado desta esp?cie quanto ? persist?ncia ? seca. Foram oferecidos a cinco novilhas 40g de sementes de macrotiloma; os animais permaneceram no piquete por 4 dias pastejando em sistema de lota??o rotacionada. Na primeira avalia??o deste experimento obteve-se uma m?dia de 215 plantas de macrotiloma na ?rea experimental. Na segunda avalia??o foi realizado o levantamento da composi??o bot?nica da pastagem, no qual o macrotiloma teve participa??o em 6,4% da ?rea experimental, com uma m?dia total de aproximadamente 380 plantas.
52

Processos biológicos de estabilização de dejetos de bovinos de Corte confinados / BIOLOGICAL PROCESSES OF WASTE STABILIZATION OF CONFINED BEEF CATTLE

Lorin, Higor Eisten Francisconi 15 August 2014 (has links)
Made available in DSpace on 2017-05-12T14:47:04Z (GMT). No. of bitstreams: 1 Higor _Lorin.pdf: 2499051 bytes, checksum: 378cc421aa2a83bfde499d6cf499588c (MD5) Previous issue date: 2014-08-15 / The increasing demand for animal protein is directly related to the confinement of animals and its premises, such as the management of the waste system. Considering that the result of stabilization processes, that is, the organic fertilizer produced, is to be used again in the production cycle, evaluating its agronomic quality becomes important information when choosing the process to be used. The objective of this work was to submit beef cattle waste, raised in feedlot, to the processes of composting, vermicomposting, static piles and anaerobic digestion, showing the stabilization and the potential of each product generated by each process. Composting and vermicomposting are more efficient at mineralization, stabilization and maturity of waste manure. The compost and vermicompost offer larger fraction of available P and K, satisfactory levels of humification and high CTC. The static process is less efficient in mineralization, stabilization and maturity wastes. The disposition of this process in the open provides the greatest loss of nutrients. The anaerobic digestion appears as the most efficient process for the preservation of macronutrients (N and K), and generates a liquid fertilizer with low CEC and high fertilizing potential, with a predominance of inorganic N in the ammonium form, readily available to plants. / A demanda crescente por proteína de origem animal está diretamente relacionada ao sistema de confinamento dos animais e suas premissas, como o manejo dos dejetos. Considerando que o resultado dos processos de estabilização, ou seja, o adubo orgânico produzido, é o produto a ser novamente utilizado no ciclo produtivo, avaliar sua qualidade agronômica, passa a ser uma informação importante na escolha do processo a ser utilizado. Objetivou-se submeter os resíduos da bovinocultura de corte, criados em sistema de confinamento, aos processos de compostagem, vermicompostagem, leiras estáticas e biodigestão anaeróbia, evidenciando a estabilização e as potencialidades de cada produto gerado pelos processos. A compostagem e a vermicompostagem são mais eficientes na mineralização, na estabilização e na maturação dos dejetos. O composto e o vermicomposto oferecem maiores frações disponíveis de P lábil e K lábil, níveis satisfatórios de humificação e alta CTC. O processo estático é o menos eficiente na mineralização, na estabilização e na maturação dos dejetos. A disposição deste processo a céu aberto propicia as maiores perdas de nutrientes. A biodigestão anaeróbia apresenta-se como o processo de estabilização mais eficiente na conservação de macronutrientes (N e K) e gera um adubo líquido com baixa CTC e de alto potencial fertilizante, com predominância de N inorgânico, em forma de amônio, prontamente disponível aos vegetais
53

Měření diverzity koprofágních brouků a jejich půdní aktivity na pastvině / Examination of the diversity and digging activity of dung beetles in pasture

ANDĚL, Tomáš January 2014 (has links)
The survey of the diversity of coprophagous beetles (Scarabaeidae, Geotrupidae, and Hydrophilidae families) and their soil activity took place at two sites in a cattle pasture in southern Bohemia (site A: 49°29'31.720"N, 14°23'44.310"E; site B: 49°29'23.257"N, 14°23'35.964"E; 575 m a. s. l.). Baited pitfall traps with fresh cow dung (1.5 l per trap) were used to capture the beetles. During the survey of the diversity of coprophagous beetle community, a total of 29 species of beetles numbering 1,189 specimens were captured from May to September 2013. Of these, the most numerous were the beetles of the genus Aphodius, who made up 79 % of the total number of captured specimens. In terms of biomass, Geotrupes spiniger (Marsham, 1802) was significant, in that it made up 24 % of the total biomass of all of the captured beetles. This species contributes most to the decomposition of dung in the pasture. The family with the least number of specimens was Hydrophilidae. Beetles from this family made up 19 % of total number. Measurement of soil activity took place repeatedly over the course of 3 weeks, always after one-week measurement of diversity. The most numerous species (A. fimetarius, A. rufus and A. fossor) showed a linear dependence of the abundances in soil-activity traps on the abundances in diversity traps from the precedent capture period. A. sticticus was one of the most numerous species during surveys of diversity (10 %). This species, belonging to the dwellers group, was not recorded in soil-activity traps, however. Large tunnellers were represented mainly by G. spiniger in traps, for which the linear dependence was not possible to confirm.
54

Micorrização e crescimento do pinhão manso sob solo degradado tratado com hidrorretentor associado à materiais orgânico /

Santos, Adriana Avelino. January 2010 (has links)
Orientador: Ana Maria Rodrigues Cassiolato / Banca: Luiz Antonio Graciolli / Banca: Gilberto Colodro / Resumo: O solo é um meio que engloba diferentes substâncias químicas e colóides e uma alta diversidade biológica. Estes componentes apresentam íntima relação funcional para sustentabilidade dos ecossistemas e, sua degradação, geralmente causada pela ação antrópica, acarreta um grande prejuízos ambientais e socioeconômicos para as gerações atuais e um enorme risco para as gerações futuras. Para reverter um processo como este, são necessárias intervenções por meio de estratégias como a revegetação. O objetivo do trabalho foi avaliar crescimento e colonização micorrízica do pinhão manso em solo decaptado que recebeu inoculo de fungos micorrizicos arbusculares, hidrogel e materiais orgânicos. O experimento foi conduzido de maio de 2008 a maio 2009, na Fazenda de Ensino, Pesquisa e Extensão (FEPE) da UNESP - Universidade Estadual Paulista, Campus de Ilha Solteira, no município de Selvíria-MS. O delineamento experimental foi o em blocos casualizado, em esquema fatorial 4x2x2, ou seja, 3 tratamentos com material orgânico (aguapé, composto e aguapé+composto), 2 tratamentos com hidrogel (com e sem adição) e 2 tratamentos de inoculação (com e sem inoculação) empregando solo proveniente de uma área preservada de cerrado como fonte de microrganimos, incluíndo fungos micorrízicos arbusculares, com 4 repetições e 5 plantas por tratamentos. O composto foi preparado com materiais de poda e esterco de bovino. Avaliou-se: o crescimento das plantas em 7 épocas diferentes, a caracterização química e número de esporos em 4 épocas, além da porcentagem de colonização micorrízica, presença de flores, número de ramos e de folhas e peso fresco e seco da parte aérea. O tratamento com hidrogel não mostrou interferência no crescimento de plantas, mas, assim como o solo-inóculo, aumentou a esporulação, a colonização micorrízica e a produção de matéria seca... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The soil is a medium that contain different chemical substances and colloids and a high biological diversity. These components have functional relationship on the sustainability of ecosystems and their degradation, usually caused by human action, which causes great socio-economic damage to the present generations and an enormous risk for the future generations. To reverse such process, action is needed using strategies, such as, revegetation. The objective of this study was to evaluate the growth and mycorrhiza colonization of Jatropha on decapitated soil that received organic materials and hydrogel. The experiment was conducted from May 2008 to May 2009, the Farm Education, Research and Extension (FEPE), UNESP - Univ. Estadual Paulista, Ilha Solteira Campus, located at Selvíria city-MS, Brazil. The experimental design was randomized blocks in factorial scheme 3x2x2, i.e., 3 treatments with organic materials (water hyacinth, compost and water hyacinth + compost), 2 hydrogel treatments (with and without addition) and 2 inoculations treatments (with and without inoculation) using natural soil from a preserved 'cerrado' area as a source of microorganisms, including mycorrhizal fungi, with 4 replications and 5 plants per each. The compound was prepared with materials pruning and cow dung. The growth of plants in 7 different times, the chemical characterization and number of spores in 4 times, and the percentage of mycorrhizal colonization, presence of flowers, branches and leaves and fresh and dry weight of air part was evaluated. Treatment with hydrogel showed no interference with the growth of plants; however, as well as the soilinoculum, they increased sporulation, root colonization and production of dry matter. The organic materials treatments positively altered the condition of the ground, plant growth, mycorrhizal colonization and sporulation; the improved performances... (Complete abstract click electronic access below) / Mestre
55

Micorrização e crescimento do pinhão manso sob solo degradado tratado com hidrorretentor associado à materiais orgânico

Santos, Adriana Avelino [UNESP] 15 January 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-01-15Bitstream added on 2014-06-13T20:39:15Z : No. of bitstreams: 1 santos_aa_me_ilha.pdf: 676511 bytes, checksum: f49f6d1a9f6dfba6539f793f9e93426c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O solo é um meio que engloba diferentes substâncias químicas e colóides e uma alta diversidade biológica. Estes componentes apresentam íntima relação funcional para sustentabilidade dos ecossistemas e, sua degradação, geralmente causada pela ação antrópica, acarreta um grande prejuízos ambientais e socioeconômicos para as gerações atuais e um enorme risco para as gerações futuras. Para reverter um processo como este, são necessárias intervenções por meio de estratégias como a revegetação. O objetivo do trabalho foi avaliar crescimento e colonização micorrízica do pinhão manso em solo decaptado que recebeu inoculo de fungos micorrizicos arbusculares, hidrogel e materiais orgânicos. O experimento foi conduzido de maio de 2008 a maio 2009, na Fazenda de Ensino, Pesquisa e Extensão (FEPE) da UNESP – Universidade Estadual Paulista, Campus de Ilha Solteira, no município de Selvíria-MS. O delineamento experimental foi o em blocos casualizado, em esquema fatorial 4x2x2, ou seja, 3 tratamentos com material orgânico (aguapé, composto e aguapé+composto), 2 tratamentos com hidrogel (com e sem adição) e 2 tratamentos de inoculação (com e sem inoculação) empregando solo proveniente de uma área preservada de cerrado como fonte de microrganimos, incluíndo fungos micorrízicos arbusculares, com 4 repetições e 5 plantas por tratamentos. O composto foi preparado com materiais de poda e esterco de bovino. Avaliou-se: o crescimento das plantas em 7 épocas diferentes, a caracterização química e número de esporos em 4 épocas, além da porcentagem de colonização micorrízica, presença de flores, número de ramos e de folhas e peso fresco e seco da parte aérea. O tratamento com hidrogel não mostrou interferência no crescimento de plantas, mas, assim como o solo-inóculo, aumentou a esporulação, a colonização micorrízica e a produção de matéria seca... / The soil is a medium that contain different chemical substances and colloids and a high biological diversity. These components have functional relationship on the sustainability of ecosystems and their degradation, usually caused by human action, which causes great socio-economic damage to the present generations and an enormous risk for the future generations. To reverse such process, action is needed using strategies, such as, revegetation. The objective of this study was to evaluate the growth and mycorrhiza colonization of Jatropha on decapitated soil that received organic materials and hydrogel. The experiment was conducted from May 2008 to May 2009, the Farm Education, Research and Extension (FEPE), UNESP - Univ. Estadual Paulista, Ilha Solteira Campus, located at Selvíria city-MS, Brazil. The experimental design was randomized blocks in factorial scheme 3x2x2, i.e., 3 treatments with organic materials (water hyacinth, compost and water hyacinth + compost), 2 hydrogel treatments (with and without addition) and 2 inoculations treatments (with and without inoculation) using natural soil from a preserved ‘cerrado’ area as a source of microorganisms, including mycorrhizal fungi, with 4 replications and 5 plants per each. The compound was prepared with materials pruning and cow dung. The growth of plants in 7 different times, the chemical characterization and number of spores in 4 times, and the percentage of mycorrhizal colonization, presence of flowers, branches and leaves and fresh and dry weight of air part was evaluated. Treatment with hydrogel showed no interference with the growth of plants; however, as well as the soilinoculum, they increased sporulation, root colonization and production of dry matter. The organic materials treatments positively altered the condition of the ground, plant growth, mycorrhizal colonization and sporulation; the improved performances... (Complete abstract click electronic access below)
56

Processos biológicos de estabilização de dejetos de bovinos de Corte confinados / Biological processes of waste stabilization of confined beef cattle

Lorin, Higor Eisten Francisconi 15 August 2014 (has links)
Made available in DSpace on 2017-07-10T19:23:51Z (GMT). No. of bitstreams: 1 Higor _Lorin.pdf: 2499051 bytes, checksum: 378cc421aa2a83bfde499d6cf499588c (MD5) Previous issue date: 2014-08-15 / The increasing demand for animal protein is directly related to the confinement of animals and its premises, such as the management of the waste system. Considering that the result of stabilization processes, that is, the organic fertilizer produced, is to be used again in the production cycle, evaluating its agronomic quality becomes important information when choosing the process to be used. The objective of this work was to submit beef cattle waste, raised in feedlot, to the processes of composting, vermicomposting, static piles and anaerobic digestion, showing the stabilization and the potential of each product generated by each process. Composting and vermicomposting are more efficient at mineralization, stabilization and maturity of waste manure. The compost and vermicompost offer larger fraction of available P and K, satisfactory levels of humification and high CTC. The static process is less efficient in mineralization, stabilization and maturity wastes. The disposition of this process in the open provides the greatest loss of nutrients. The anaerobic digestion appears as the most efficient process for the preservation of macronutrients (N and K), and generates a liquid fertilizer with low CEC and high fertilizing potential, with a predominance of inorganic N in the ammonium form, readily available to plants. / A demanda crescente por proteína de origem animal está diretamente relacionada ao sistema de confinamento dos animais e suas premissas, como o manejo dos dejetos. Considerando que o resultado dos processos de estabilização, ou seja, o adubo orgânico produzido, é o produto a ser novamente utilizado no ciclo produtivo, avaliar sua qualidade agronômica, passa a ser uma informação importante na escolha do processo a ser utilizado. Objetivou-se submeter os resíduos da bovinocultura de corte, criados em sistema de confinamento, aos processos de compostagem, vermicompostagem, leiras estáticas e biodigestão anaeróbia, evidenciando a estabilização e as potencialidades de cada produto gerado pelos processos. A compostagem e a vermicompostagem são mais eficientes na mineralização, na estabilização e na maturação dos dejetos. O composto e o vermicomposto oferecem maiores frações disponíveis de P lábil e K lábil, níveis satisfatórios de humificação e alta CTC. O processo estático é o menos eficiente na mineralização, na estabilização e na maturação dos dejetos. A disposição deste processo a céu aberto propicia as maiores perdas de nutrientes. A biodigestão anaeróbia apresenta-se como o processo de estabilização mais eficiente na conservação de macronutrientes (N e K) e gera um adubo líquido com baixa CTC e de alto potencial fertilizante, com predominância de N inorgânico, em forma de amônio, prontamente disponível aos vegetais
57

Local and regional factors influencing dung beetle assemblage structure across an environmental gradient in Botswana

Tshikae, Balatlhane Power 19 October 2011 (has links)
The taxonomic composition, structure, and diversity of current local species assemblages results from an interacting complex of historical, regional ecological and local ecological factors. Structural differences between such current species assemblages are primarily determined by changing ecological conditions across spatial gradients. These conditions may change abruptly or they may represent a gradual divergence. Across the Botswana Kalahari basin there is a gradual northeast-southwest aridity and dung type gradient, which was demonstrated to strongly influence dung beetle assemblage structure at six study sites from Chobe National Park to the Central Kalahari Reserve to the Kgalagadi Transfrontier Park using carrion and four dung types as bait (pig, elephant, cattle, sheep). Regional patterns were primarily influenced by climate (rainfall) while dung type mainly showed a local influence on patterns of variation. Four distinct biogeographical groups were defined for the study region comprising widespread, northeast/widespread, northeast, and arid southwest Kalahari-centred species. Biogeographical diversity was higher in the more mesic NE than the arid SW but varied somewhat between bait types. In the SW, Kalahari endemics dominated all bait types. In general, abundance and species richness declined along the aridity gradient although the pattern was uneven due to low numbers in the north of the Central Kalahari Game Reserve. Species showed high turnover (beta – diversity), particularly between the moister NE and the Kalahari/Savanna ecotone. Hierarchical Analysis of Oblique Factors showed statistically distinct separation between assemblage structure at the six study sites and that the proportion of mesic NE shared influence on assemblage composition declined towards the SW where there was an increase in Kalahari endemics. Similarly the proportion of arid SW shared influence declined towards the NE. Plotting these results onto a map showed that the point of intersection between shared NE or SW influence lay very close to the ecotone between SW (Kalahari Xeric Savanna) and NE-centred ecoregions (Acacia-Baikiaea Savanna) defined for the area by Olson et al. (2001). In terms of dung type diversity, increasing aridity across the Kalahari represents a gradient of diminishing resources with the loss of large dung types to the SW and increasing dominance of dung pellets. Several different patterns of response were shown using different methods. Four principal patterns of bait type association were indicated by one method. Another method showed that, rather than diminishing numbers of competing species leading to widening niche widths to the SW, niche widths were narrowest at the Kalahari / mesic Savanna ecotone. Using several other multivariate techniques, three different patterns of dung type resource partitioning were demonstrated that paralleled the aridity gradient, one common to the NE and two to the SW. The historical, regional and local ecological factors influencing these patterns of dung beetle assemblage structure are discussed as well as implications and recommendations for conservation. / Thesis (PhD)--University of Pretoria, 2011. / Zoology and Entomology / unrestricted
58

An Implementation of Splitting for Dung Style Argumentation Frameworks

Wong, Renata 19 February 2018 (has links)
Argumentation and reasoning have been an area of research in such disciplines as philosophy, logic and artificial intelligence for quite some time now. In the area of AI, knowledge needed for reasoning can be represented using various kinds of representation systems. The natural problem posed by this fact is that of possible incompatibility between heterogeneous systems as far as communication between them is concerned. This imposes a limitation on the possibility of extending smaller knowledge bases to larger ones. In order to facilitate a common platform for exchange across the systems unified formalisms for the different approaches to knowledge representation are required. This was the motivation for Dung [11] to propose in his 1995 paper an approach that later came to be known as an abstract argumentation framework. Roughly speaking, Dung's arguments are abstract entities which are related to each other by the means of conflicts between them. An intuitive graphical representation of Dung style framework is a graph whose nodes stand for arguments and whose edges stand for conflicts. A framework postulated this way is on one hand too general to be used on its own, but on the other hand it is general enough as to allow for varied extensions increasing its expressiveness, which indeed have been proposed. They include value-based argumentation frameworks by Bench-Capon et al. [6], preference-based argumentation frameworks by Amgoud and Cayrol [1] and bipolar argumentation frameworks by Brewka and Woltran [7], to name a few. The present thesis is concerned with yet another variation of Dung's framework: the concept of splitting. It was developed by Baumann [4] with one of the underlying purposes being that the computation time in frameworks which have been split into two parts and then computed separately may show some improvement in comparison to their variant without splitting. It was one of the main tasks of my work to develop an efficient algorithm for the splitting operation based on the theoretical framework given in [4]. On the other hand I hoped to confirm the expectation that splitting can indeed make a computation perform better.
59

Vliv pastvy koní na vegetaci / Horses and vegetation

Třeštíková, Tereza January 2011 (has links)
Many studies show that large herbivores can have an important impact on the composition of vegetation. With the establishment of a year round, low density grazing regime, plant ecologists and nature managers expect that through selective grazing, herbivores will create a mosaic of different vegetation communities varying in structure and plant species composition. It is believed that such a mosaic in the end will guarantee a high degree of biodiversity. Grazing will, therefore, seem to be a suitable means to maintain grass. Also important is the ability of herbivores affect vegetation through endozoochory. In this thesis I have tried to find out what species of diet horses prefer regarding to plant species and what plant species they can spread through out endozoochory. I have compared this knowledge with the composition of pasture and meadow vegetation at the researched locality in Malenice and Hoslovice. With the purpose of finding out the preferences I established spots where I registered data on vegetation before pasture and the time intervals during the pasture. Afterwards, I researched the amount of sprouts and the composition of seedlings in excrements that I let germinate. I had to create phytocenologic shots from the pastures and meadows to compare the species of composition of grazed and...
60

Conservation de l’entomofaune ordinaire : enjeux scientifiques et sociétaux / Conserving Ordinary entomofauna : scientific & social stakes

Leandro, Camila 29 November 2018 (has links)
En regardant de près les outils juridiques et autres leviers, pour la conservation de la biodiversité, il semblerait que les invertébrés, et notamment les insectes, soient minoritaires ou absents. Ce constat est d’autant plus paradoxal lorsque l’on sait que 2/3 de la diversité biologique est composée par des insectes. Comment cette diversité essentielle pour le fonctionnement des écosystèmes se retrouve-t-elle dans l’angle mort de la conservation ?La première réponse avancée est le manque d’outils techniques pour étudier ces organismes petits et relativement insaisissables. La rencontre avec les nouvelles méthodes techniques pour la détection et l’étude des insectes est plus que jamais nécessaire. En effet, ces leviers permettront de faciliter l’étude de ces organismes, d’augmenter les connaissances et ainsi de développer une conservation plus adéquate. Nous évoquerons deux approches en particulier : la détection avec des outils moléculaires et l’utilisation de modèles statistiques pour l’exploration de la distribution potentielle des espèces.Mais les connaissances sont également fondées sur la demande sociétale. Et les connaissances alimentent elles-mêmes les outils de protection et de conservation de la biodiversité. À l’échelle des invertébrés, des disparités existent, privilégiant les « grands papillons bleus » aux « petits diptères marrons ». De fait, l’enjeu le plus important pour déverrouiller la conservation des insectes réside dans l’humain et la perception qu’il a de cette biodiversité. À travers une approche de psychologie de la conservation, nous sonderons la perception du grand public sur les insectes. De même, avec une approche de recherche-action-participative, nous tenterons d’engager divers acteurs vers la conservation d’un groupe d’insectes ordinaires : les coléoptères coprophages. Notre volonté est de proposer des moyens pour sensibiliser, éduquer et engager la société dans cet enjeu majeur qu’est la conservation de l’entomofaune. / Looking closely at the legal tools and other levers for preserving biodiversity, it would seem that invertebrates, in particular insects, are in a minority, or absent. This observation is all the more paradoxical when we know that 2/3 of the biological diversity consists of insects. How does this diversity, essential for the functioning of the ecosystems, find itself in the dead angle of conservation?The first answer that is usually put forward is lack of technical tools to study these small and relatively elusive animals. Getting to know and use new technical methods for the detection and the study of insects is more than ever necessary. Indeed, these levers will facilitate the study of these animals, and will thus increase knowledge, which will lead to developing more adequate conservation strategies. We shall evoke two approaches in particular: detection with molecular tools and use of statistical models to explore the potential distribution of the species.But knowledge is also based on what society asks for. Public interest orients the tools of protection and preservation of biodiversity. Among invertebrates, disparities exist, favoring the “big blue butterflies” over the “small brown dipterans”. A simple coincidence? No. Actually, the decisive factor to unlock the preservation of insects rests in human beings and how they perceive this biodiversity. Using a conservation psychology approach, we will explore how the general public perceives insects. We will also draw on participatory action research to see how various conservation actors can be committed towards preserving a group of ordinary insects: coprophagous beetles. Our aim is to propose ways to raise awareness, educate and engage society to this major issue: preserving entomofauna.

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