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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

Protocolo experimental para avaliação do potencial de disseminação de gramíneas exóticas invasoras por animais de montaria / Experimental protocol for the assessment of the potential spread of invasive exotic grasses for riding animals

Matsubara, Luciana Yukie 28 January 2016 (has links)
O uso de animais de montaria em áreas naturais tem gerado grande preocupação, pois podem gerar impactos ambientais. Um dos problemas que precisa ser investigado é a relação entre animais de montaria e a presença de plantas exóticas em áreas de alto valor ecológico. Assim, o presente trabalho teve como objetivo testar um protocolo de germinação para sementes de duas espécies de gramíneas, braquiária (Urochloa decumbens) e capim gordura (Melinis minutiflora) que passaram pelo trato digestório de cavalos. As sementes foram ofertadas aos animais junto com a ração com posterior coleta das fezes. No experimento foram realizados três tratamento. No tratamento \"braquiária\" foram ofertadas sementes de Urochloa decumbens, no tratamento \"capim gordura\" foram ofertadas sementes de Melinis minutiflora e o \"sem tratamento\" foi ofertada apenas a ração. Parte das sementes foram retiradas das fezes e submetidas a testes de germinação e o material restante foi utilizado para testar a capacidade germinativa das sementes diretamente nas fezes em um ambiente controlado. Na germinadora verificou-se que as sementes que passaram pelo trato digestório dos cavalos tiveram uma menor taxa de germinação comparadas com as sementes com tratamento de quebra de dormência. No tratamento feito em casa de vegetação as sementes que foram retiradas das fezes e que germinaram foram identificadas. Não houve diferença na taxa de germinação entre os cavalos, o que ocorreu entre os tratamentos. No tratamento braquiária predominou a germinação de Urochloa decumbens, no tratamento capim gordura a maior taxa de germinação de Melinis minutiflora e no sem tratamento predominou o nascimento de outras espécies. As sementes estudas tem potencial de germinar, crescer e frutificar, porém não se sabe se as espécies podem formar uma população capaz de colonizar novas áreas. / The use of riding animals in natural areas has caused great concern because their use cause environmental impacts. One of the problems that needs to be investigated is the relationship between the use of riding animals and the presence of exotic plants in natural areas. This study aimed to test a germination protocol for the of two species Urochloa decumbens and Melinis minutiflora that has passed through the digestive tract of the horse. The seeds were offered to horses and their feces were collected. Tree treatments were set, in \"braquiaria\" treatment seeds Urochloa decumbens were offered to the horses, in the \"capim gordura\" treatment seeds of Melinis minutiflora offered and the untreated were offered only horse food. Part of the seeds were removed from the feces and undergo germination test and the remain of the feces were used to test in a green house. The germination rate of the seed from de horse dung was lower than germination rate of the dormancy breaking treatment seeds. The seeds that germinate on the greenhouse were identified. There were no difference between the germination rate between treatments, but there was between species in braquiaria treatment predominated the germination of Urochloa decumbens in the grass fat treatment most Melinis minutiflora germination rate and the untreated predominated the germination of other species. Seeds from horse dung has the potential to germinate, grow and bear fruit, but it is not known if this species can form a population able to colonize new areas.
2

Protocolo experimental para avaliação do potencial de disseminação de gramíneas exóticas invasoras por animais de montaria / Experimental protocol for the assessment of the potential spread of invasive exotic grasses for riding animals

Luciana Yukie Matsubara 28 January 2016 (has links)
O uso de animais de montaria em áreas naturais tem gerado grande preocupação, pois podem gerar impactos ambientais. Um dos problemas que precisa ser investigado é a relação entre animais de montaria e a presença de plantas exóticas em áreas de alto valor ecológico. Assim, o presente trabalho teve como objetivo testar um protocolo de germinação para sementes de duas espécies de gramíneas, braquiária (Urochloa decumbens) e capim gordura (Melinis minutiflora) que passaram pelo trato digestório de cavalos. As sementes foram ofertadas aos animais junto com a ração com posterior coleta das fezes. No experimento foram realizados três tratamento. No tratamento \"braquiária\" foram ofertadas sementes de Urochloa decumbens, no tratamento \"capim gordura\" foram ofertadas sementes de Melinis minutiflora e o \"sem tratamento\" foi ofertada apenas a ração. Parte das sementes foram retiradas das fezes e submetidas a testes de germinação e o material restante foi utilizado para testar a capacidade germinativa das sementes diretamente nas fezes em um ambiente controlado. Na germinadora verificou-se que as sementes que passaram pelo trato digestório dos cavalos tiveram uma menor taxa de germinação comparadas com as sementes com tratamento de quebra de dormência. No tratamento feito em casa de vegetação as sementes que foram retiradas das fezes e que germinaram foram identificadas. Não houve diferença na taxa de germinação entre os cavalos, o que ocorreu entre os tratamentos. No tratamento braquiária predominou a germinação de Urochloa decumbens, no tratamento capim gordura a maior taxa de germinação de Melinis minutiflora e no sem tratamento predominou o nascimento de outras espécies. As sementes estudas tem potencial de germinar, crescer e frutificar, porém não se sabe se as espécies podem formar uma população capaz de colonizar novas áreas. / The use of riding animals in natural areas has caused great concern because their use cause environmental impacts. One of the problems that needs to be investigated is the relationship between the use of riding animals and the presence of exotic plants in natural areas. This study aimed to test a germination protocol for the of two species Urochloa decumbens and Melinis minutiflora that has passed through the digestive tract of the horse. The seeds were offered to horses and their feces were collected. Tree treatments were set, in \"braquiaria\" treatment seeds Urochloa decumbens were offered to the horses, in the \"capim gordura\" treatment seeds of Melinis minutiflora offered and the untreated were offered only horse food. Part of the seeds were removed from the feces and undergo germination test and the remain of the feces were used to test in a green house. The germination rate of the seed from de horse dung was lower than germination rate of the dormancy breaking treatment seeds. The seeds that germinate on the greenhouse were identified. There were no difference between the germination rate between treatments, but there was between species in braquiaria treatment predominated the germination of Urochloa decumbens in the grass fat treatment most Melinis minutiflora germination rate and the untreated predominated the germination of other species. Seeds from horse dung has the potential to germinate, grow and bear fruit, but it is not known if this species can form a population able to colonize new areas.
3

Volně žijící herbivoři jako vektor šíření druhů v opuštěné krajině / Free-ranging herbivores as a dispersal vector for species in abandoned landscape

Lepková, Barbora January 2014 (has links)
Endozoochory is an important part of plant-animal relationship. In model area of the Doupov Mountains large herbivore mammals, such as red deer, sika deer and wild boar, act as effective seed dispersers. Out of 282 dung samples 29 719 seedlings of 91 species emerged. The most common species was Urtica dioica (80 % of all seedlings). The amount of seeds in dung as well as species composition were highly dependent on dispersing animal, both showed strong seasonality and differences between two studied localities. Frequency of species in dung did not correspond to their frequency in vegetation suggesting strong preferences of herbivores as predators. However more research is needed to test this hypothesis. Given very high time demands for samples processing beforehand the emergence experiment, the influence of concentration by washing through on seedling emergence and species composition was tested. According to preliminary results more seedlings and species emerge from concentrated samples. However, concentration has no effect on emergence of U. dioica as the most common species. Concentration of samples by running water is recommended for faster emergence in greenhouse conditions. Preliminary results also suggest that the approximation of number of seedlings/species on weight of dry mass is not...
4

Dispersal, distribution and genetic diversity of Melampyrum subalpinum group

CHLUMSKÝ, Jan January 2016 (has links)
This thesis is focused on the dispersal, distribution, and genetic diversity of the taxonomically highly diverse Melampyrum subalpinum group. A complete revision of the localities of M. subalpinum in the Czech Republic and Slovakia is presented. The genetic variation and population structure of the M. subalpinum group across its distribution range is described based on allozymes, nuclear and chloroplast gene sequencing, and genome size. Signs of historical hybridization with M. nemorosum were found in some populations. A comparison of seed dispersal by ants between the co-occurring M. subalpinum and M. pratense and the influence of differences in this process are presented. A new mean of seed dispersal (endozoochory) is introduced for Melampyrum. Myrmecochorous dispersal distances are tested and Holocene migration possibilities are discussed taking into account endozoochory.
5

O potencial de dispersão de sementes por Saguinus bicolor (SPIX, 1823) (Primates: Callitrichidae)

Fernandes, Leandro Siqueira, 92-99349-9980 04 June 2018 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-10-15T15:16:47Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação-Leandro.S.Fernandes.pdf: 1359976 bytes, checksum: 6a343537d69f7467ed412811332b1c45 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-10-15T15:16:59Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação-Leandro.S.Fernandes.pdf: 1359976 bytes, checksum: 6a343537d69f7467ed412811332b1c45 (MD5) / Made available in DSpace on 2018-10-15T15:16:59Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação-Leandro.S.Fernandes.pdf: 1359976 bytes, checksum: 6a343537d69f7467ed412811332b1c45 (MD5) Previous issue date: 2018-06-04 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Seed dispersal is an extremely important process in the population dynamics of plants. This process can be mediated by dispersing agents as in the case of primates. During feeding these animals can spit or swallow the seeds of the fruits. When swallowing the seeds, a process known as endozoochory, these animals can increase germination, or even move seeds away from the parent plant, this can favor plants by avoiding competition, predation and disease on seeds and seedlings. We performed experiments such as the free-living tamarim (Saguinus bicolor) primate in the laboratory, using 23 species of fruits that are part of its diet, to test the effect of the passage of seeds through the digestive tract and which factors influence the time of seed retention. Tamarins favor most defecated seeds, increasing germination (50%) and speed of emergence (38,88%). The retention time was not influenced by the characteristics of the seeds or the amount of fiber in the fruit pulp, and the first appearance of the seeds in the feces was correlated with the quantities of swallowed seeds. Thus, tamarim can be considered an effective dispersant potential because the seeds remain viable after being defecated and the time the seeds are retained possibly favors dispersion. Therefore, seed dispersion mediated by tamarins may be beneficial for the maintenance and recovery of environments where these animals transit. / A dispersão de sementes é um processo extremamente importante na dinâmica populacional das plantas. Esse processo pode ser intermediado por agentes dispersores como no caso dos primatas. Durante a alimentação esses animais podem cuspir ou engolir as sementes dos frutos. Ao engolirem as sementes, processo conhecido como endozoocoria, esses animais podem aumentar a germinação, ou até mesmo, deslocar as sementes para longe da planta progenitora, isso pode favorecer as plantas por evitar a competição, predação e doenças sobre as sementes e plântulas. Realizamos experimentos com o primata sauim-de-coleira (Saguinus bicolor) em laboratório, usando 23 espécies de frutos que fazem parte da sua dieta, para testar o efeito da passagem das sementes através do trato digestório e quais fatores influenciam o tempo de retenção das sementes. Os sauins favorecem a maioria das sementes defecadas, aumentado a germinação (50%) e a velocidade de emergência (38,88%). O tempo de retenção não foi influenciado pelas caraterísticas das sementes ou quantidade de fibras na polpa dos frutos, entretanto, o primeiro aparecimento das sementes nas fezes mostrou-se correlacionado com a quantidades de sementes engolidas. Dessa forma, o sauim pode ser considerado um potencial dispersor eficaz, porque as sementes permanecem viáveis após serem defecadas e o tempo que as sementes ficam retidas possivelmente favorece a dispersão. Portanto, a dispersão de sementes mediada pelos sauins pode ser benéfica para a manutenção e recuperação de ambientes onde estes animais transitam.
6

Frugivoria por morcegos (Chiroptera: Phyllostomidae) na Mata atlântica do Nordeste e padrões germinativos de sementes após passagem pelo sistema digestivo

Pereira, Arivania Santos 23 February 2017 (has links)
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Chiropterocory has been identified as the most effective means of dispersal in the tropics, 549 species of neotropical plants have already been compiled in analyzes of dispersion by bats. Understanding the processes that interfere in the choice of the item to be dispersed, as well as the mechanisms that act on seed dispersal effectiveness, are essential steps in the understanding of the bat-plant interactions. This study aimed to evaluate the food ecology of a group of Carollia perspicillata, also evaluating the endozoochory effect of this species and of Platyrrhinus lineatus on the germination patterns of the main plant species consumed by them. The study was carried out in two areas of Atlantic Forest. The first one is a limestone under-rock shelter, inhabited by bats of the species Carollia perspicillata in the municipality of Laranjeiras-Sergipe. The second area was the campus of the Federal University of Sergipe, which includes a group of Platyrrhinus lineatus, residentsfor at least five years. The fecal sampling for the analysis of endozoochory by P. lineatus and C. perspicillata, and the analysis of the diet for the latter, were carried out by means of plastictarpaulins extended below the groupings of the respective species, during 72 hours/month in the period of one year. In parallel, phenological observations were made. The germination tests were performed at ambient conditions and formed by two treatments, one control group and one test group. Each treatment consisted of four replicates by species with 400 seed each. Mean germination time (MGT), germination speed index (GSI), seed synchrony and germinability were considered. In terms of food ecology, approximately 323,400 seeds were obtained, classified into 16 species and 12 families. Thesynzoochorous species represented the smallest portion of the general seed sample (n = 5), which was predominated by endozoochorous seeds (n = 11). Five of these species (Annona montana, Syagrus coronata, Senna georgica, Aegiphila vitelliniflora and Chomelia obtusa) are being reported for the first time in the group diet. The species with the highest numbers of seeds found in the shelters were Piper amalago (n = 160,594), Solanum paniculatum (79,322) and Maclura tinctoria (60,691). Although the number of seeds of P. amalago was considerably higher, there were no significant differences between the consumption of these three main species in generalnor in the different periods of the year. The richness of plant species in the diet did not differ significantly between the periods of the year. C. perpicillata kept the germination patterns of the M. tinctoria species neutral. In P. amalago, endozoochory was also neutral for germinability, but the MGT, GSI and Synchrony of the seeds of the test group were significantly lower than those in the control group. With the exception of the germinability of the test group that was greater than the control, the germinative parameters of S. paniculatum remained neutral. For P. lineatus, except for the MGT test, which was significantly lower than the control group, no significant differences were observed for S. paniculatum. C. perspicillata has been shown to significantly increase the germinability of S. paniculatum in relation to P. lineatus. The data of this study shows the functional role of these species of bats in the dispersal effectiveness. It is suggested the execution of endozoochory studies with concise experimental designs that contemplate the amplitude of variables that can interfere in the process. / A quiropterocoria tem sido apontada como o meio mais efetivo de dispersão nos trópicos, 549 espécies de plantas neotropicais já foram compiladas em análises de dispersão por morcegos. Entender os processos que interferem na escolha do item a ser disperso, bem como os mecanismos que atuam na efetividade da dispersão de sementes, são etapas imprescindíveis no avanço do entendimento das interações morcego-planta. Esse estudo se propôs a avaliar a ecologia alimentar de um grupo de Carollia perspicillata, avaliando também o efeito da endozoocoria da referida espécie e de Platyrrhinus lineatus nos padrões de germinação das principais espécies vegetais por elas consumidas. O estudo foi realizado em duas áreas de Mata Atlântica. A primeira, trata-se de um abrigo sob-rocha calcaria, habitada por morcegos da espécie Carollia perspicillata no município de Laranjeiras-Sergipe. A segunda área, foi o campus da Universidade Federal de Sergipe, que contempla um agrupamento de Platyrrhinus lineatus residentes a pelo menos cinco anos. As coletas das fezes para análise da endozoocoria por P. lineatus e C. perspicillata, e dieta deste último, foram realizadas por meio de lonas plásticas estendidas abaixo dos agrupamentos das respectivas espécies, durante 72 horas/mês no período de um ano. Paralelamente, foram realizadas observações fenológicas. Os testes de germinação foram realizados em condições ambientes e formados por dois tratamentos, um grupo controle e um grupo teste. Cada tratamento foi formado por quatro réplicas, com 400 sementes cada, por espécie. Foi considerado o tempo médio de germinação (TMG), o índice de velocidade da germinação (IVG), a sincronia e a germinabilidade das sementes por tratamento. No tocante a frugivoria, foram obtidas aproximadamente 323.400 sementes, classificadas em 16 espécies e 12 famílias. As espécies sinzoocóricas encontradas representaram a menor parcela da amostra geral de sementes (n=5), que foi predominada por sementes endozoocóricas (n=11). Cinco dessas espécies (Annona montana, Syagrus coronata, Senna georgica, Aegiphila vitelliniflora e Chomelia obtusa), estão sendo reportadas pela primeira vez na dieta do grupo. As espécies com maiores números de sementes encontradas nos abrigos foram Piper amalago (n= 160.594), Solanum paniculatum (79.322) e Maclura tinctoria (60.691). Embora o número de sementes de P. amalago tenha sido consideravelmente maior, não foram observadas diferenças significativas entre o consumo dessas três principais espécies de modo geral, bem como nos distintos períodos do ano. A riqueza de espécies vegetais na dieta, também não diferiu significativamente entre os períodos do ano. C. perpicillata manteve neutro os padrões germinativos da espécie M. tinctoria. Em P. amalago, a endozocoocoria também foi neutra para germinabilidade, porém o TMG, o IVG e a Sincronia das sementes do grupo teste foram significativamente menores do que as do grupo controle. À exceção da germinabilidade do grupo teste que foi maior que o controle, os parâmetros germinativos de S. paniculatum mantiveram-se neutros. Para P. lineatus, à exceção do TMG do teste, que foi significativamente menor que o grupo controle, não foram observadas diferenças significativas para S. paniculatum. C. perspicillata demonstrou aumentar significativamente a germinabilidade de S. paniculatum em relação P. lineatus. Os dados desse estudo evidenciam o papel funcional das referidas espécies de morcegos na efetividade da dispersão. Sugere-se a execução de estudos endozoocóricos com delineamentos experimentais concisos que contemplem a amplitude de variáveis que podem interferir no processo.
7

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...

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