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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.
21

Where Mountain Lions Traverse: Insights from Landscape Genetics in Southwestern United States and Northwestern Mexico

Naidu, Ashwin January 2015 (has links)
The projected growth in human population, rapid urbanization, and expansion of structures like highways and canals pose a major threat to the future survival of wildlife, particularly large terrestrial mammals. In many cases, wild animal populations have been restricted to fragmented habitat islands due to anthropogenic developments, endangering them to local extinction. Current and future wildlife conservation and management strategies are leading to the implementation of mitigation measures such as creation of wildlife habitat corridors. In this light, novel and interdisciplinary research methods such as approaches in the field of landscape genetics are proving to be increasingly useful and necessary for assessing the status of wildlife populations and furthering efficacy of conservation programs and management efforts. In this 5-year research study, I review literature in the field of landscape genetics, highlighting studies and their applications toward wildlife conservation over the past decade (2005-2014). I then use a landscape genetic approach to understand the potential impact of natural and human-made barriers in and around the northern Sonoran Desert on one of the widest-ranging mammals in the world, the mountain lion (Puma concolor). I employ recently developed genetic tools to assess the current population genetic status of mountain lions in this region and Geographic Information Systems (GIS) tools to relate observations to landscape features through interpretive maps. I further investigate the utility of GIS and expert-based models in connectivity conservation and suggest validating them with information on genetic relatedness and functional connectivity among mountain lions. Lastly, in many parts of this document, I emphasize the use of these methods and data sharing in conservation planning as well as wildlife management.
22

Weta affairs : an investigation into the population structure and possible hybridisation of two tree weta species (hemideina) in Canterbury.

van Heugten, Rachel January 2015 (has links)
Recently, hybridisation has been increasingly recognised as contributing to the extinction of species; with the risk especially high for rare species hybridising with more common species. Such risks have raised concerns for the Banks Peninsula tree weta, Hemideina ricta, which is restricted to the eastern half of Banks Peninsula and in some areas lives in sympatry with the more widespread Canterbury species, H. femorata. A previous genetics study found evidence of hybridisation between these two species. However, conclusions made by this study were likely limited by its small sample size. To further assess the risk hybridisation poses to the conservation of these species, a larger genetic study was undertaken. With hybridisation between H. ricta and H. femorata previously hypothesized to be a rare event, modelling of likely sympatric zones was undertaken to optimize the sampling effort. The results of genetic analysis on the resulting samples were consistent with the previous study, in that they suggest hybridisation does occur but is fairly rare. To help determine what processes are maintaining the distinction between the two species, the current study has expanded to incorporate observations of mating behaviour and egg hatching experiments. As well as potential risks from hybridisation, H. ricta and H. femorata have also suffered habitat loss. The Canterbury region has been transformed by the introduction of exotic plant species, fire and logging, with only small patches of native bush remaining. The loss and fragmentation of the native forest is likely to impact the forest fauna such as the tree weta. A previous study of a closely related species H. maori, in a naturally fragmented habitat, determined that dispersal between suitable habitat patches was fairly limited. Therefore, similar to their habitat, H. ricta populations may be small and isolated. Such populations are prone to the fixation of deleterious alleles as well as a loss of genetic diversity. Deleterious traits not only have a short term negative impact but a lack of genetic variation can prevent adaptation in the long term. In the past, studies of population structure have included the influence of intrinsic factors, such as dispersal capabilities but neglected extrinsic factors, such as the environment. The current study uses microsatellite markers to determine the population structure of both species and where possible, maps of land-cover are analyzed for a correlation with genetic structure.
23

Testing general rules in landscape ecology: Understanding the effects of landscape pattern on the avifauna of South East Queensland

Danielle Shanahan Unknown Date (has links)
Human land-use has a profound influence on wildlife populations; habitat loss can directly decrease population size and carrying capacity, and isolation of the remaining populations can increase their extinction probability. Landscape ecology as a discipline has worked towards creating general rules for the way species respond to landscape change. These rules include, for example, estimates of thresholds at which populations respond more severely to landscape level variables, or general theories as to which species will be more susceptible to landscape change. The demand for these generalisations is driven by the need for inexpensive, rapid and effective methods to manage problems caused by landscape change. The question as to whether general rules are accurate or useful solicits mixed responses from scientists and conservation managers. The most cited reason for this mixed response is the empirical inconsistencies in the way species respond to landscape change. In this thesis I suggest that general rules must be tested in an a priori fashion to directly assess their utility and assist in their translation from theory to practical tool. My primary aim is to test general rules in landscape ecology through creating a priori models; these models are based on ecological theories and existing species and landscape information. My secondary aim is to enhance the understanding of landscape level habitat fragmentation problems for birds in South East Queensland, Australia. I address these aims within four main data chapters as summarised below, where Chapter 1 is a broad introduction to the topic. Chapter 2 asks the question: can general rules and threshold theory be used to predict bird species patch occupancy in a fragmented landscape? I create a simple decision tree model based on threshold theories in landscape ecology, and use this to predict presence or absence of 17 forest bird species in a largely agricultural landscape. This decision tree is broadly based on theoretical patch area and connectivity threshold estimates, and incorporates basic species specific information (such as habitat suitability and mobility). I test this model using a presence/absence survey data set. The process of assessing for which species the model did not work is revealing: I show that the accuracy of ‘present’ predictions is somewhat compromised for habitat specialist species and ‘absent’ predictions are compromised for generalist species. Through creating the ‘optimal’ decision tree models for these species I show that these inaccuracies are likely to arise from vegetation mapping problems, including the lack of a ‘habitat quality’ measure. The study therefore highlights the need for high quality vegetation maps to carry out effective planning. For the majority of species I achieve reasonable predictive success. This study provides hope that general rules have some predictive ability in landscape ecology, and highlights the value of testing models to assess why, and for which species general rules may or may not work. In Chapter 3, I assess the utility of basic ecological principles for predicting the relative value of vegetation patches for specific bird species, focusing on a highly altered urban landscape. I create a model based on the mechanisms expected to be driving species abundance within urban landscapes where most sensitive bird species are likely to be already lost. The model states that a bird species will be more abundance in areas where the vegetation structure matches a species foraging height requirements; however, this effect will be moderated by the landscape context of the patch. From this model I create an index to quantify and rank the predicted value of patches for 30 species of interest in unmanaged and revegetated urban sites, in Brisbane city, Australia. I test the model using bird abundance data, and show that it achieved a reasonable level of predictive accuracy. The model presented within this study is significant as it has relatively low complexity and limited data requirements, yet provides a means to assess how altering the landscape context and vegetation structure within a patch may enhance the abundance of bird species of interest. With further development, the relative simplicity of the model should make it easy to use for land managers. In Chapter 4 I aim to examine how landscape features influence spatial genetic relatedness patterns at a fine, within-population scale on bird species with different life-history traits. I argue that individual level movement characteristics (particularly dispersal routes) in a variable landscape will drive these spatial genetic patterns; thus I create an a priori model based on this theory to make more specific quantifiable predictions of relatedness patterns. I use animal movement theory to deduce these movement characteristics (particularly the strength of avoidance of habitat boundaries) for species with different life-history traits, and apply the model for two closely related passerine bird species which co-occur within South East Queensland (the yellow-throated scrubwren, Sericornis citreogularis, a habitat specialist; and the white-browed scrubwren, Sericornis frontalis, a habitat generalist). I test these models using data on pairwise genetic distances between individuals of each species. The key outcome of this study is that the genetic data supports my predictions that individual level movement characteristics are a mechanistic driver of within-population spatial genetic patterns. For the habitat specialist bird species, the genetic data supported a model which incorporated a strong avoidance response to habitat boundaries and for the generalist species no response to habitat boundaries. This study takes a novel approach to an individual-based genetics study, making specific quantifiable predictions of how a species may be impacted by different landscape features. This research could have significant implications for conservation management, particularly for understanding and managing population responses to a changing landscape, and the early stages of fragmentation. In Chapter 5 I address the question of whether urban revegetation is more successful if it is used to extend the area of existing vegetation, or enhance connectivity in the landscape. This study is novel; for instead of assessing the factors influencing the extinction of a species in a patch, I assess the factors influencing colonisation. Using bird survey data, I use hierarchical partitioning and model selection approaches to determine the relative effect of connectivity and patch area on bird species richness and abundance in revegetated patches. The key finding was that connectivity provided better model fit for bird species richness, and total patch area and connectivity was better for mean bird abundance. My results suggest that the conservation goals of revegetation efforts, particularly in an urban landscape, must be considered when planning a revegetation program. Using revegetation to increase patch area may be the most effective approach for ensuring species persistence over time (i.e. abundance). However, to attract more species into an area enhancing the total area connected in the landscape may be a better approach. In this thesis I explicitly test general rules and theories in landscape ecology within a priori predictive models. Through their generality, the models I develop are potentially suitable for application in other ecosystems. The process of synthesising these models in a simple form, and testing them in a real landscape was revealing. I was able to examine where some general rules do not work, and also where they may not apply or need adjusting. I strived to create models that are easy to use and understand, particularly within Chapters 2 and 4, by trading off simplicity and accuracy. The models produce accurate results to the point that they are arguably valuable tools for landscape managers. This is achieved without compromising their accessibility, and so the research has the potential to transcend the gap between science and real world utility.
24

THE EFFECT OF HABITAT FRAGMENTATION ON THE SPATIAL POPULATION GENETIC STRUCTURE OF SOUTHERN PINE BEETLE (DENDROCTONUS FRONTALIS)

Hailu, Solomon Ghebremeskel 01 May 2011 (has links)
Southern pine beetle (SPB), Dendroctonus frontalis (Zimmerman), is one of the most destructive insect pests of pine trees in southern United States, Mexico and Central America. There is relatively little information on the effect of habitat fragmentation on the connectivity and the spatial population genetics of SPB. This study therefore, adds to previously generated information by assessing how habitat fragmentation affects the spatial population genetic structure of SPB. It also introduces a new approach to the study of bark beetle population dynamics by assessing how landscape variables shape their effective dispersal. To address this issue, a suite of eight highly polymorphic DNA microsatellite markers were used to measure SPB movement over a representative range of SPB habitat and non-habitat (matrix). At the broadest scale, highly significant genetic differentiation suggests that the sampled populations are not panmictic. Loci with higher variability yielded higher resolution for both the infinite allele model based measure of differentiation (FST) and the stepwise mutation based measure (RST) estimates. It is apparent that allelic frequency differences, allelic size ranges and repeat motif played a role in the observed patterns of pair-wise differentiations between the sampled localities. It is supposed that gene flow, wide-range dispersal and recent divergent time could have contributed to the lower level of genetic structure observed in the pair wise estimates. The sampled populations did not show any differentiation attributable to the host species from which they were collected. Mantel test of genetic distance and Euclidean geographic distance revealed no correlation. Mantel tests of the correlation between genetic distance and cost weighted Euclidean distances also suggest that dispersal of SPB across geographic barriers is not significantly reduced. Thus, landscape features and host preference do not appear to have had an impact on population genetic structure of SPB. Since movements of these beetles were not significantly hindered by environmental factors like major rivers, roads, elevation and host type, it is advisable for regional pest management offices to put an effort and coordinate their prevention and management plans in a broader scale to alleviate the problem associated with this native insect pest. Disequilibrium in the observed homogenized pattern of the beetle in this study suggests human contribution in the dispersal of SPB. Therefore, stringent control is deemed necessary in transportation of logs. This could improve our pest management system hence its positive implication in timber industry is obvious.
25

Distribuição espacial de raças bovinas e dos valores genéticos de animais Brangus e suas associações com o ambiente / Spatial distribution of bovine breeds and genetic values of animals Brangus and their association with environment

Alfonzo, Evelyn Priscila München January 2018 (has links)
Dois estudos foram realizados com o objetivo de analisar a distribuição espacial de diferentes raças bovinas e dos valores genéticos de animais Brangus no Brasil, relacionando sua ocorrência com variáveis climáticas, físicas e socioeconômicas. O objetivo do primeiro estudo foi analisar a relação das variáveis climáticas, físicas e socioeconômicas com a distribuição de raças bovinas. Neste estudo utilizou-se as informações município e estado das raças Aberdeen Angus, Ayrshire, Braford, Brangus, Charolês, Devon, Flamenga, Hereford, Pinzgauer, Shorthorn e Simental. As raças foram classificadas conforme sua finalidade: carne, dupla aptidão e leite e posteriormente espacializadas no programa ArcGis 10.2. As raças leiteiras estudadas estavam localizadas nos estados do Rio Grande do Sul e Santa Catarina, as raças de duplo propósito em Minas Gerais e no Rio Grande do Sul e as raças de carne estão concentradas na região sul do país. As regressões logísticas demonstraram que as raças de corte e dupla aptidão tendem a ser criadas em regiões com menor temperatura máxima e média, menor amplitude térmica e ITU, porém em municípios com alta umidade e altitude, menor produto interno bruto, pouca orientação técnica, baixo controle de doenças e parasitas e pouca rotação de pastagens A análise de variância mostrou que as raças de carne, leite e dupla aptidão não variaram para as características climáticas, físicas e socioeconômicas. No segundo estudo objetivou-se analisar a associação das variáveis climáticas, físicas e socioeconômicas com a distribuição dos valores genéticos para características de crescimento e perímetro escrotal de animais da raça Brangus. Foram utilizados registros de 84.703 animais da raça Brangus, nascidos entre 2000 e 2010 distribuídos em 65 fazendas do Brasil. Os animais localizaram-se nos estados RS, PR, SP, MG, GO, MG e MS. Á desmama, as maiores médias dos valores genéticos por fazenda estão agrupadas no cluster 1 e ao sobreano agruparam-se no cluster 2. Os maiores valores genéticos ficaram fortemente relacionadas com amplitude térmica e área municipal. Ter conhecimento da distribuição espacial de raças bovinas e dos valores genéticos de animais Brangus pode auxiliar no desenvolvimento de índices ambientais, avaliações genéticas e escolha de animais para determinados ambientes. / Two studies were conducted in order to analyze the spatial distribution of different breeds and breeding values of Brangus animals in Brazil, relating their occurrence to climatic, physical and socioeconomic variables. The aim of the first study was to analyze the relationship of climatic, physical and socioeconomic variables with the distribution of bovine breeds. In this study we used the municipality and state information of the Aberdeen Angus, Ayrshire, Braford, Brangus, Charolais, Devon, Flemish, Hereford, Pinzgauer, Shorthorn and Simmental breeds. Breeds were classified according to their purpose: beef, dual purpose and milk and spatialized using ArcGis 10.2. The dairy breeds studied were located in the states of Rio Grande do Sul and Santa Catarina, the dual purpose breeds in Minas Gerais and Rio Grande do Sul and the beef breeds are concentrated in the southern region of the country. Logistic regression showed that both beef and dual purpose cattle are more likely to be raised in municipalities with lower maximum and average temperatures, lower thermic amplitude and THI, although, with high humidity and altitude, with lower gross domestic product, where technical guidance, rotation of pastures and control of diseases and parasites were low Analysis of variance showed that beef, dairy and dual purpose breeds did not ranged for climatic, physical and socio-economic characteristics. The second study aimed to analyze the association of climate, physical and socio-economic characteristics with the distribution of breeding values of growths traits and scrotal perimeter of Brangus animals. Records of 84.703 Brangus animals, born between 2000 and 2010 distributed in 65 farms in Brazil were used. Cluster analysis formed three clusters of average breeding values per farm. Animals were located in the Brazilian states of RS, PR, SP, MG, GO, MG and MS. At weaning, the highest averages of breeding values per farm were grouped in cluster 1 and to yearling in cluster 2. The highest breeding values were strongly related to thermal amplitude and municipal area. knowledge the spatial distribution of cattle breeds and breeding values of Brangus animals can help in the development of environmental indices, genetic evaluations and in the choice of animals for certain environments.
26

Distribuição espacial de raças bovinas e dos valores genéticos de animais Brangus e suas associações com o ambiente / Spatial distribution of bovine breeds and genetic values of animals Brangus and their association with environment

Alfonzo, Evelyn Priscila München January 2018 (has links)
Dois estudos foram realizados com o objetivo de analisar a distribuição espacial de diferentes raças bovinas e dos valores genéticos de animais Brangus no Brasil, relacionando sua ocorrência com variáveis climáticas, físicas e socioeconômicas. O objetivo do primeiro estudo foi analisar a relação das variáveis climáticas, físicas e socioeconômicas com a distribuição de raças bovinas. Neste estudo utilizou-se as informações município e estado das raças Aberdeen Angus, Ayrshire, Braford, Brangus, Charolês, Devon, Flamenga, Hereford, Pinzgauer, Shorthorn e Simental. As raças foram classificadas conforme sua finalidade: carne, dupla aptidão e leite e posteriormente espacializadas no programa ArcGis 10.2. As raças leiteiras estudadas estavam localizadas nos estados do Rio Grande do Sul e Santa Catarina, as raças de duplo propósito em Minas Gerais e no Rio Grande do Sul e as raças de carne estão concentradas na região sul do país. As regressões logísticas demonstraram que as raças de corte e dupla aptidão tendem a ser criadas em regiões com menor temperatura máxima e média, menor amplitude térmica e ITU, porém em municípios com alta umidade e altitude, menor produto interno bruto, pouca orientação técnica, baixo controle de doenças e parasitas e pouca rotação de pastagens A análise de variância mostrou que as raças de carne, leite e dupla aptidão não variaram para as características climáticas, físicas e socioeconômicas. No segundo estudo objetivou-se analisar a associação das variáveis climáticas, físicas e socioeconômicas com a distribuição dos valores genéticos para características de crescimento e perímetro escrotal de animais da raça Brangus. Foram utilizados registros de 84.703 animais da raça Brangus, nascidos entre 2000 e 2010 distribuídos em 65 fazendas do Brasil. Os animais localizaram-se nos estados RS, PR, SP, MG, GO, MG e MS. Á desmama, as maiores médias dos valores genéticos por fazenda estão agrupadas no cluster 1 e ao sobreano agruparam-se no cluster 2. Os maiores valores genéticos ficaram fortemente relacionadas com amplitude térmica e área municipal. Ter conhecimento da distribuição espacial de raças bovinas e dos valores genéticos de animais Brangus pode auxiliar no desenvolvimento de índices ambientais, avaliações genéticas e escolha de animais para determinados ambientes. / Two studies were conducted in order to analyze the spatial distribution of different breeds and breeding values of Brangus animals in Brazil, relating their occurrence to climatic, physical and socioeconomic variables. The aim of the first study was to analyze the relationship of climatic, physical and socioeconomic variables with the distribution of bovine breeds. In this study we used the municipality and state information of the Aberdeen Angus, Ayrshire, Braford, Brangus, Charolais, Devon, Flemish, Hereford, Pinzgauer, Shorthorn and Simmental breeds. Breeds were classified according to their purpose: beef, dual purpose and milk and spatialized using ArcGis 10.2. The dairy breeds studied were located in the states of Rio Grande do Sul and Santa Catarina, the dual purpose breeds in Minas Gerais and Rio Grande do Sul and the beef breeds are concentrated in the southern region of the country. Logistic regression showed that both beef and dual purpose cattle are more likely to be raised in municipalities with lower maximum and average temperatures, lower thermic amplitude and THI, although, with high humidity and altitude, with lower gross domestic product, where technical guidance, rotation of pastures and control of diseases and parasites were low Analysis of variance showed that beef, dairy and dual purpose breeds did not ranged for climatic, physical and socio-economic characteristics. The second study aimed to analyze the association of climate, physical and socio-economic characteristics with the distribution of breeding values of growths traits and scrotal perimeter of Brangus animals. Records of 84.703 Brangus animals, born between 2000 and 2010 distributed in 65 farms in Brazil were used. Cluster analysis formed three clusters of average breeding values per farm. Animals were located in the Brazilian states of RS, PR, SP, MG, GO, MG and MS. At weaning, the highest averages of breeding values per farm were grouped in cluster 1 and to yearling in cluster 2. The highest breeding values were strongly related to thermal amplitude and municipal area. knowledge the spatial distribution of cattle breeds and breeding values of Brangus animals can help in the development of environmental indices, genetic evaluations and in the choice of animals for certain environments.
27

O papel da estrutura da paisagem na variabilidade genética da palmeira Euterpe edulis na Mata Atlântica / The role of landscape structure on genetic variability of the palm Euterpe edulis along the Atlantic rainforest

Carvalho, Carolina da Silva 30 April 2013 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2014-12-11T16:19:43Z No. of bitstreams: 2 Dissertação - Carolina da Silva Carvalho - 2013.pdf: 2199681 bytes, checksum: ed22c98d9a9a33449462463405206c01 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-12-11T19:02:22Z (GMT) No. of bitstreams: 2 Dissertação - Carolina da Silva Carvalho - 2013.pdf: 2199681 bytes, checksum: ed22c98d9a9a33449462463405206c01 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-12-11T19:02:22Z (GMT). No. of bitstreams: 2 Dissertação - Carolina da Silva Carvalho - 2013.pdf: 2199681 bytes, checksum: ed22c98d9a9a33449462463405206c01 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-04-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Não consta resumo em outro idioma. / Essa dissertação está estruturada em dois capítulos cujo objetivo geral foi entender como características da paisagem influenciam a variação e a estruturação genética, usando a abordagem de genética da paisagem e a palmeira Euterpe edulis (Arecaceae) como modelo de estudo. A genética da paisagem surgiu a partir da junção de três grandes áreas da ciência: ecologia da paisagem, ecologia espacial e genética de populações (Manel et al. 2003). Difere-se de disciplinas clássicas como genética de populações e filogeografia, pois incorpora testes explícitos de heterogeneidade ambiental a fim de entender a distribuição da variabilidade genética no espaço (Storfer et al. 2007). Dentre as abordagens frequentemente realizadas na genética da paisagem podemos: identificar características da paisagem que influenciam a conectividade e diversidade genética, realizar design de corredores ecológicos e reservas, e predizer impactos de futuras mudanças ambientais na conectividade e permanência da espécie (Spear et al. 2010). No entanto, a primeira abordagem é a mais utilizada nos estudos, onde são testados o efeito do relevo, da hidrografia, das estradas (Spear et al. 2005), dos corredores, do tamanho e do isolamento dos fragmentos, e da proporção de habitat (Coulon et al. 2004, Dixo et al. 2009) sobre o fluxo gênico e variação genética. Além disso, a genética da paisagem pode ser particularmente importante para explicar padrões originados a partir de processos micro-evolutivos (Manel et al. 2003), principalmente em paisagens extremamente fragmentadas. Como é uma área relativamente nova, estudiosos da genética da paisagem vem colocando esforços para testar uma grande variedade de métodos estatísticos (e.g. Cushman et al. 2006, Cushman & Landguth 2010, Wagner & Fortin 2012), técnicas de tratamento espaciais de dados, e favorecendo-se da alta tecnologia do desenvolvimento de marcadores genéticos (Spear et al. 2005, Storfer et al. 2007). No entanto, apesar do crescente número de publicações, Storfer e colaboradores (2010) encontraram que a maioria dos estudos em genética da paisagem ainda está concentrada na América do Norte e Europa, sendo que 90% dos estudos incluem apenas uma espécie e apenas 14,5% desses é realizado com plantas. Portanto, no primeiro capítulo dessa dissertação intitulado “Linking genetics to landscape: large scale study of an Atlantic Rainforest palm species Euterpe edulis” foi realizada uma metanálise com o objetivo de avaliar a contribuição relativa da heterogeneidade ambiental, da adequabilidade ambiental para o estabelecimento da espécie, e dos efeitos antrópicos para explicar a variação da diversidade genética e do grau de endocruzamento em populações de Euterpe edulis ao longo do bioma Mata Atlântica. O segundo capítulo intitulado: “Matrix resistance and habitat loss determines patterns of genetic differentiation in a Rainforest palm species”, avaliou se a perda de habitat e a fragmentação afetam a variabilidade e diferenciação genética do E. edulis. Para responder a nossa pergunta, sete paisagens de 2 km foram analisadas no estado de São Paulo, sudeste do Brasil, totalizando 22 áreas. Para acessar a variabilidade e diferenciação genética dessas áreas, utilizamos 8 locos de microssatélites e usamos comparação de modelos com múltiplas hipóteses concorrentes baseado no critério de informação de Akaike (AIC).
28

Desenvolvimento de superfícies de resistência explicando a variação genética por modelagem orientada por padrão: uma análise com espécies de árvores de cerrado / Development of resistance surfaces explaining genetic variation using pattern oriented modeling: analysis with cerrado tree species

Silva e Souza, Kelly da 25 April 2016 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-10-18T14:14:08Z No. of bitstreams: 2 Dissertação - Kelly da Silva e Souza - 2016.pdf: 2710469 bytes, checksum: cbe461f0d7a743f38a8a7043c982acf0 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2016-10-18T16:44:37Z (GMT) No. of bitstreams: 2 Dissertação - Kelly da Silva e Souza - 2016.pdf: 2710469 bytes, checksum: cbe461f0d7a743f38a8a7043c982acf0 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-10-18T16:44:37Z (GMT). No. of bitstreams: 2 Dissertação - Kelly da Silva e Souza - 2016.pdf: 2710469 bytes, checksum: cbe461f0d7a743f38a8a7043c982acf0 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-04-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / To understand how landscape features spatially affect the genetic structure of a population , we propose the creation of resistance surfaces using an approach Pattern Oriented Modeling of genetic divergence (FST parwise) among baru populations (Dipteryx alata). To compose the resistance surface, we employed land use layers in an area of 25 baru populations, generating 10000 resistance surfaces with randomized cost values between 0 and 100. We use these surfaces to calculate matrices pairwise effective resistance to the circuitscap. Mantel test and its variations revealed a correlation of FST parwise with geographical distance of 0.48. The correlation between FST pairwise and the resistance matrices ranged between r = -0.2019 and r= 0.6736. We used multiple regression matrices to select the best (most satisfactory) models through Akaike (AIC). Three models were selected to contain the parameters that best explain the genetic divergence with ΔAIC below three. The ΔAIC values were used to calculate the AIC-weight (WI) and evaluate the individual contribution of each parameter in the selected surfaces. The selected models suggest that the areas with lower resistance are characterized as Savanna Arboreo Dense and Savanna Grassy Woody. Roads, big rivers, and agricultural lands cause higher resistance. / Para entendermos como as características da paisagem afetam espacialmente a estrutura genética populacional, propomos a criação de superfícies de resistência utilizando uma abordagem de Modelagem Orientada pelo Padrão da divergência genética (FST) entre as populações de baru (Dipteryx alata), uma árvore amplamente distribuída na região do Cerrado do Brasil Central. Para compor as superfícies de resistência, utilizamos camadas de uso da terra na área em que as 25 populações de baru em estudo estão inseridas. Geramos 10 mil superfícies de resistência com valores de custo aleatorizados entre 0 e 100 em intervalos de 1. Usamos essas superfícies para calcular matrizes de resistência efetiva par-a-par com o circuitscape, um programa que calcula os valores de resistência fazendo uma analogia entre a conectividade elétrica e os dados genéticos da espécie em estudo. Calculamos testes de Mantel e suas variações entre o FST e cada uma das matrizes de resistências. A correlação do FST par-a-par com a distância geográfica, foi de 0,48. Para a correlação entre FST par a par e as matrizes de resistência, os testes de Mantel resultaram em coeficientes de correlação variando entre r = -0,2019 e r = 0,6736. Usamos a regressão múltipla de matrizes para seleção dos melhores modelos pelo critério de Akaike (AIC). Três modelos foram selecionados como sendo os que contém os parâmetros que melhor explicam a divergência genética pelo critério de Akaike com ΔAIC menor que 3. Os valores ΔAIC foram usados para calcular o peso do AIC em cada modelo (wi) e foram utilizados para avaliar a contribuição individual de cada parâmetro nas superfícies selecionadas. Modelos selecionados sugerem que as áreas com menor resistência são as caracterizadas por Cerrado de Savana Arbóreo Densa (cerradão) e Savana Gramíneo Lenhosa (campo limpo). As estradas, grandes rios e áreas agrícolas do Cerrado causam maior resistência.
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Distribuição espacial de raças bovinas e dos valores genéticos de animais Brangus e suas associações com o ambiente / Spatial distribution of bovine breeds and genetic values of animals Brangus and their association with environment

Alfonzo, Evelyn Priscila München January 2018 (has links)
Dois estudos foram realizados com o objetivo de analisar a distribuição espacial de diferentes raças bovinas e dos valores genéticos de animais Brangus no Brasil, relacionando sua ocorrência com variáveis climáticas, físicas e socioeconômicas. O objetivo do primeiro estudo foi analisar a relação das variáveis climáticas, físicas e socioeconômicas com a distribuição de raças bovinas. Neste estudo utilizou-se as informações município e estado das raças Aberdeen Angus, Ayrshire, Braford, Brangus, Charolês, Devon, Flamenga, Hereford, Pinzgauer, Shorthorn e Simental. As raças foram classificadas conforme sua finalidade: carne, dupla aptidão e leite e posteriormente espacializadas no programa ArcGis 10.2. As raças leiteiras estudadas estavam localizadas nos estados do Rio Grande do Sul e Santa Catarina, as raças de duplo propósito em Minas Gerais e no Rio Grande do Sul e as raças de carne estão concentradas na região sul do país. As regressões logísticas demonstraram que as raças de corte e dupla aptidão tendem a ser criadas em regiões com menor temperatura máxima e média, menor amplitude térmica e ITU, porém em municípios com alta umidade e altitude, menor produto interno bruto, pouca orientação técnica, baixo controle de doenças e parasitas e pouca rotação de pastagens A análise de variância mostrou que as raças de carne, leite e dupla aptidão não variaram para as características climáticas, físicas e socioeconômicas. No segundo estudo objetivou-se analisar a associação das variáveis climáticas, físicas e socioeconômicas com a distribuição dos valores genéticos para características de crescimento e perímetro escrotal de animais da raça Brangus. Foram utilizados registros de 84.703 animais da raça Brangus, nascidos entre 2000 e 2010 distribuídos em 65 fazendas do Brasil. Os animais localizaram-se nos estados RS, PR, SP, MG, GO, MG e MS. Á desmama, as maiores médias dos valores genéticos por fazenda estão agrupadas no cluster 1 e ao sobreano agruparam-se no cluster 2. Os maiores valores genéticos ficaram fortemente relacionadas com amplitude térmica e área municipal. Ter conhecimento da distribuição espacial de raças bovinas e dos valores genéticos de animais Brangus pode auxiliar no desenvolvimento de índices ambientais, avaliações genéticas e escolha de animais para determinados ambientes. / Two studies were conducted in order to analyze the spatial distribution of different breeds and breeding values of Brangus animals in Brazil, relating their occurrence to climatic, physical and socioeconomic variables. The aim of the first study was to analyze the relationship of climatic, physical and socioeconomic variables with the distribution of bovine breeds. In this study we used the municipality and state information of the Aberdeen Angus, Ayrshire, Braford, Brangus, Charolais, Devon, Flemish, Hereford, Pinzgauer, Shorthorn and Simmental breeds. Breeds were classified according to their purpose: beef, dual purpose and milk and spatialized using ArcGis 10.2. The dairy breeds studied were located in the states of Rio Grande do Sul and Santa Catarina, the dual purpose breeds in Minas Gerais and Rio Grande do Sul and the beef breeds are concentrated in the southern region of the country. Logistic regression showed that both beef and dual purpose cattle are more likely to be raised in municipalities with lower maximum and average temperatures, lower thermic amplitude and THI, although, with high humidity and altitude, with lower gross domestic product, where technical guidance, rotation of pastures and control of diseases and parasites were low Analysis of variance showed that beef, dairy and dual purpose breeds did not ranged for climatic, physical and socio-economic characteristics. The second study aimed to analyze the association of climate, physical and socio-economic characteristics with the distribution of breeding values of growths traits and scrotal perimeter of Brangus animals. Records of 84.703 Brangus animals, born between 2000 and 2010 distributed in 65 farms in Brazil were used. Cluster analysis formed three clusters of average breeding values per farm. Animals were located in the Brazilian states of RS, PR, SP, MG, GO, MG and MS. At weaning, the highest averages of breeding values per farm were grouped in cluster 1 and to yearling in cluster 2. The highest breeding values were strongly related to thermal amplitude and municipal area. knowledge the spatial distribution of cattle breeds and breeding values of Brangus animals can help in the development of environmental indices, genetic evaluations and in the choice of animals for certain environments.
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Vliv rozšíření, populační dynamiky a krajinné genetiky, a preference druhů kořisti na ochranu levharta sněžného v Nepálu / Implication of snow leopard distribution, population dynamics and landscape genetics, and prey preference for its conservation in Nepal

Shrestha, Bikram January 2021 (has links)
This thesis deals with an endangered large mammal species - snow leopard, its distribution, population dynamics, landscape genetics and connectivity, trophic ecology and human-snow leopard conflicts in the Nepalese Himalaya (Sagarmatha National Park (SNP), Lower Mustang (LM) and Upper Manang (UM) in the Annapurna Conservation Area, during Wet and Dry seasons in 2014-2016. In the case of snow leopard study, we used data obtained from camera traps, scat's genetic analysis and monitoring of fresh pugmarks and scrapes while direct count method was used to study for its main prey, blue sheep and Himalayan tahr. In study 1, we assessed the determinants of habitat suitability of snow leopards using MaxEnt model and mapped the distribution of suitable habitat for snow leopards in Nepal. Altitude and Annual mean temperature are important common factors contributing to snow leopard habitat suitability within the area studied, which is indicated by both the percentage contribution of environmental variables and Jackknife test from MaxEnt model. Some other uncommon factors also seem to play a role, as they were important in at least one of the analyses. These were: distance from road, and precipitation of driest month but their importance has to be considered with caution. In study 2, we present our...

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