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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.
341

Fecundidade na Região Norte: uma análise socioeconômica e espacial do perfil reprodutivo das mulheres nortistas

Santiago, Débora Ramos 20 December 2010 (has links)
Made available in DSpace on 2015-04-11T13:52:51Z (GMT). No. of bitstreams: 1 DISSERTACAO-DEBORA SANTIAGO.pdf: 2062054 bytes, checksum: f70771550d8c1d845b864efadc430d33 (MD5) Previous issue date: 2010-12-20 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Fertility is considered an important determinant of population dynamics. Your levels and trends have a significant influence on population growth and age distribution, constituting an important tool for analysis on the reproductive behavior of a population. The aim of this study is to contribute to the understanding of reproductive behavior of women Northerners, considering their socioeconomic factors, spacial differences and reproductive intentions. For this research was used as the primary basis the information of Census, PNAD and the PNDS considering the last decades of the twentieth century. Thus it was found that fertility in the North, similarly to what has happening throughout the country, has shown a declining trend with a levels that are very close to the rate of population replacement. But this decline is not manifested uniformly among different areas and socioeconomic categories, in poor areas and with the worst socioeconomic conditions in the region the fertility rates are higher, for example in the states of Acre and of Amazonas. It was observed that the variables years of education, income and female work are inversely related to the level of fertility, because the higher they are, fewer children northern women tend to have. Regarding the variables color, marital status and condition of the home, it was verified that black women living in consensual unions and those who live in rural areas were those that emerged with the highest fertility levels. Finally it was founded changes in reproductive intentions of women northerners in the last decades, which began to opt for smaller families as the ideal standard, wishing to have small number of children. The perspective for the coming years is that fertility continues to decline across the region and social strata. Understanding this demographic phenomenon constitutes an important tool for developing public policies compling with social demands effectively, allowing a better quality of life for the population as a whole. / A fecundidade é considerada um importante determinante da dinâmica populacional. Seus níveis e tendências têm significativa influência no crescimento da população e na distribuição etária, constituindo importante subsídio para análises sobre o comportamento reprodutivo de uma população. O objetivo desse estudo é contribuir para a compreensão do comportamento reprodutivo das mulheres Nortistas, considerando os seus determinantes socioeconômicos, diferenciais espaciais e intenções reprodutivas. Para a realização dessa pesquisa utilizou-se como base principal de informações as referentes ao Censo Demográfico, à PNAD e à PNDS considerando as ultimas décadas do século XX. Assim verificou-se que a fecundidade na Região Norte, semelhantemente ao que tem ocorrido em todo o país, vem apresentando tendência declinante com níveis muito próximos aos da taxa de reposição populacional. Porém esse declínio não se manifesta uniformemente entre os diferentes espaços e categorias socioeconômicas, sendo a fecundidade elevada nas áreas mais pobres e com as piores condições socioeconômicas da região, por exemplo, nos estados do Acre e do Amazonas. Observou-se que as variáveis anos de estudo, renda e trabalho feminino possuem relação inversa com o nível de fecundidade, pois quanto maiores elas forem menos filhos as mulheres nortistas tenderão a ter. Quanto às variáveis cor, situação conjugal e condição de domicílio, verificou-se que as mulheres pretas, que vivem em união consensual e aquelas que moram nas áreas rurais foram as que despontaram com os maiores níveis de fecundidade da região. Por fim constataram-se modificações nas intenções reprodutivas das mulheres nortistas nas ultimas décadas, que passaram a optar por famílias menores como padrão ideal, desejando cada vez mais ter um reduzido número de filhos. A perspectiva para os próximos anos é que a fecundidade continue em declínio em toda a região e estratos sociais. A compreensão desse fenômeno demográfico constitui-se numa importante ferramenta para a elaboração de políticas públicas que possam atender às demandas sociais de forma eficaz, permitindo uma melhor qualidade de vida para a população como um todo.
342

Simulação da dinâmica do Aedes Aegypti com Gnumeric: uma proposta interdisciplinar para o ensino de progressões e gráficos de funções / Simulation of Aedes Aegypti dynamics with Gnumeric: an interdisciplinary proposal for progressions teaching and function graphing

Reis, Celmo Jose dos 11 July 2016 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-05T12:22:29Z No. of bitstreams: 2 Dissertação - Celmo José dos Reis - 2016.pdf: 3460998 bytes, checksum: c611b6ef55a816f6919e420bf4255a44 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-05T12:23:42Z (GMT) No. of bitstreams: 2 Dissertação - Celmo José dos Reis - 2016.pdf: 3460998 bytes, checksum: c611b6ef55a816f6919e420bf4255a44 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-05T12:23:42Z (GMT). No. of bitstreams: 2 Dissertação - Celmo José dos Reis - 2016.pdf: 3460998 bytes, checksum: c611b6ef55a816f6919e420bf4255a44 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-07-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Given the need for a better interaction between teachers and students in math classes, there is, currently, an increasing search for new educational tools that involve computational resources. This monograph proposes a teaching strategy that makes the study of mathematics more enjoyable and engaging, showing how math can be used in order to provide the high school student elements to understand the reason to study math and what connection it has with their daily lives. Starting from the observation that the teaching of mathematics in public schools has struggled for acceptance of the students because mathematics is presented mostly in a traditional way, i.e., it presents the student with a pile of ready-made formulas without practical sense for them. This makes it become exhausting and ineffective, leading the student even despise mathematics. Faced with these issues, we propose the use of the program Gnumeric as a tool in teaching Progressions, Functions and Graphics. Currently, interdisciplinarity has been present in education and, following this idea, we use along with the program the mathematical modeling of population dynamics, in particular the dynamics of the Aedes aegypti mosquito as a motivation to work with the proposed contents. It is further proposed to inform and alert students about diseases caused by the mosquito Aedes aegypti. / Tendo em vista a necessidade de uma melhor interação entre docentes e alunos em sala de aula na abordagem de conteúdos matemáticos, atualmente é grande a busca por novas ferramentas didáticas que envolvem recursos computacionais. Propõe-se com este trabalho, fornecer uma ferramenta didática de ensino que torne o estudo da matemática mais prazeroso e envolvente, que seja mais realístico e que forneça ao aluno do ensino médio condições de avaliação do porquê estudar matemática e qual a ligação destes conteúdos com seu dia a dia, partindo da observação de que o ensino da Matemática nas escolas públicas vem enfrentando dificuldades de aceitação e aprendizagem pelos alunos, pois os conteúdos matemáticos são apresentados quase sempre de forma tradicional, ou seja, apresenta-se ao aluno um amontoado de fórmulas prontas sem sentido prático para os mesmos. Dessa forma, o ensino se torna desgastante e ineficaz, levando o aluno a até mesmo, desprezar a Matemática. Frente a essas questões, esse trabalho propõe o uso do aplicativo Gnumeric como ferramenta de apoio no ensino de progressões, funções e construção de gráficos. Atualmente, a interdisciplinaridade tem estado presente na educação e, seguindo essa ideia, usa-se juntamente ao aplicativo a modelagem matemática da dinâmica de populações, em particular do Aedes aegypti como motivação para se trabalhar o conteúdo proposto. Propõe-se ainda, informar e alertar os alunos acerca de doenças causadas pelo mosquito Aedes aegypti.
343

Estimação de parâmetros de populações de plantas daninhas usando inferência Bayesiana / Estimation of the parameters of weeds population using Bayesian inference

Marcel Rodrigues Lopes 20 April 2007 (has links)
O banco de sementes de plantas daninhas pode vir a ser um sério problema para a atividade agrícola por manter infestações por longos períodos. A dinâmica da população de plantas daninhas pode ser representada por modelos matemáticos que relaciona as densidades de sementes produzidas e de plântulas em áreas de cultivo. Os valores dos parâmetros dos modelos podem ser inferidos diretamente de experimentação e análise estatística. O presente trabalho tem por objetivo estimar parâmetros de populações das plantas daninhas anuais denominadas Digitaria ciliares, Panicum maximum e Euphorbia heterophylla e avaliar um modelo espacial com 2 e 3 parâmetros, a partir de um experimento conduzido em cultura de Zea mays (milho) usando inferência Bayesiana. / The seeds bank of weed could be a serious problem to the agricultural activity because it maintains infestations for long periods. The dynamics of weed populations can be described by mathematical models that relates the produced seeds and seedlings densities in areas of crop. The values of the parameters of the models can be inferred from experimentation and statistics analysis. The objective of this work is to estimate parameters of anual weed populations denoted Digitaria ciliares, Panicum maximum e Euphorbia heterophylla and evaluate a spatial model with 2 and 3 parameters from experimental data of Zea mays (corn) fields using Bayesian inference.
344

Estrutura populacional e filogeografia de Drosophila antonietae Tidon & Sene / Population structure and phylogeography of Drosophila antonietae Tidon & Sene

Jaqueline Reginato Koser 13 March 2015 (has links)
A espécie Drosophila antoneitae é cactófila, ovipositando principalmente no cacto hospedeiro Cereus hildmaniannus. Ambas as espécies são encontradas em solos drenados ou afloramentos de rocha na região de Missiones, um dos núcleos de Floresta Tropical Sazonalmente Seca (FTSS), e no litoral sul-brasileiro. O núcleo de Missiones compreende a base dos rios Paraná-Paraguai e é uma possível área de estabilidade climática durante as oscilações do Quaternário. Para avaliar a distribuição atual da diversidade genética de D. antonietae e sua associação com alterações na paisagem, foram realizadas as seguintes análises: estruturação populacional, estabelecimento de hipóteses filogeográficas e de eventos demográficos, testes de neutralidade e modelagem de nicho atual e paleoecológico. O gene mitocondrial COI e nuclear period foram analisados. O gene period é pouco variável e a distribuição da variabilidade genética é homogênea. O gene COI é bastante polimórfico e há estruturação entre as populações formando três agrupamentos: um em Santa Catarina e Rio Grande do Sul, outro no Paraná e São Paulo e o terceiro no centro-oeste brasileiro. A população do centro-oeste brasileiro provavelmente é a mais antiga, coincidente com a área do estudo mais estável climaticamente. Este agrupamento forma uma rede de haplótipos separada, devido alta estruturação e isolamento, provavelmente tendo no rio Paraná uma importante barreira de fluxo gênico. Sugere-se que o provável centro de dispersão das demais populações de D. antonietae se localiza no sudeste brasileiro, e que houve diversos eventos de migração para as demais regiões de sua distribuição. Há indícios de polimorfismo compartilhado devido à recente diversificação das populações. Ambos os agrupamentos genéticos exibem sinais de expansão populacional, especialmente nas áreas de borda no núcleo de Missiones, onde o clima parece ter sido menos estável. O período de expansão demográfica é recente e coincidente com a maior extensão da vegetação seca, que também pode ter papel fundamental na estruturação das populações. / Drosophila antoneitae is a cactophilic species, ovipositing primarily in the host cacti Cereus hildmaniannus. Both species are found in drained soils or rocky outcrops in the Missiones region - one of the Seasonally Dry Tropical Forest (SDTF) nucleis, and in south Brazilian coast. The Missiones nuclei comprises the basin of the Paraná-Paraguai Rivers and it is a possible area of climatic stability during the Quaternary oscillations. To evaluate the current distribution of the genetic diversity of D. antoneitae and its association with landscape modifications, the following analyses were performed: populational structure, establishment of phylogeographic hypotheses and demographic events, neutrality tests and paleoecological niche modeling. The mitochondrial gene COI and the nuclear gene period were analyzed. The gene period had low genetic diversity and an homogeneity on the distribution of genetic variability. For gene COI analysis we found a high polymorphism and genetic structure among populations, forming three groups: one in Santa Catarina and Rio Grande do Sul, another in Paraná and São Paulo and the third in the midwestern Brazil. The midwestern population is probably the oldest one, coinciding with the most climatically stable area of this study. This group forms a network of separate haplotypes, due to a high structuring and isolation, probably with Paraná River acting as major barrier for gene flow. We suggest that the possible center of dispersion of the remaining populations of D. antonietae is located in southeastern Brazil, and there were several migration events to other regions of its distribution. There is evidence of shared polymorphism due to recent diversification of populations. Both gene clusters exhibit signs of population expansion, especially in border areas at the Missiones nuclei, where the climate seems less stable. The demographic expansion period is recent and coincides with the major expansion of dry vegetation, which can also play a critical role in structuring populations.
345

Modelagem física e computacional da dinâmica populacional do mosquito Aedes aegypti

Yamashita, William Massayuki Sakaguchi 17 August 2018 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-10-24T13:02:25Z No. of bitstreams: 1 williammassayukisakaguchiyamashita.pdf: 6136709 bytes, checksum: 40c2acb18069362d16c30a65e17521d1 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-11-23T12:20:00Z (GMT) No. of bitstreams: 1 williammassayukisakaguchiyamashita.pdf: 6136709 bytes, checksum: 40c2acb18069362d16c30a65e17521d1 (MD5) / Made available in DSpace on 2018-11-23T12:20:00Z (GMT). No. of bitstreams: 1 williammassayukisakaguchiyamashita.pdf: 6136709 bytes, checksum: 40c2acb18069362d16c30a65e17521d1 (MD5) Previous issue date: 2018-08-17 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A incidência global dos vírus da Dengue e, mais recentemente, do Zika, Chikungunya e Febre Amarela, tem aumentado o interesse em estudar e compreender a dinâmica populacional do mosquito. Essas doenças são predominantemente disseminadas pelo Aedes aegypti nos países tropicais e subtropicais do mundo. Compreender essa dinâmica é importante para a saúde pública nos países, onde as condições climáticas e ambientais são favoráveis para a propagação destas doenças. Por essa razão, modelos que estudam a dinâmica populacional em uma cidade são de suma importância. Este trabalho discute a modelagem numérica da dinâmica populacional do mosquito Aedes aegypti em uma vizinhança urbana de uma cidade. Em um primeiro momento, apresentamos os resultados teóricos preliminares de modelos unidimensionais. Em seguida, propomos um modelo bidimensional utilizando equações diferenciais parciais. Este modelo permite incorporar fatores externos (vento e inseticidas químicos) e dados topográficos (ruas, blocos de construção, parques, florestas e praias). O modelo proposto foi testado em exemplos envolvendo duas cidades brasileiras (o centro da cidade de Juiz de Fora e a Praia de Copacabana no Rio de Janeiro). / The global incidence of the Dengue virus and, more recently, the Zika, Chikungunya and Yellow Fever, has increased interest in studying and understanding the population dynamics of the mosquito. These diseases are predominantly disseminated by Aedes aegypti in the tropical and subtropical countries of the world. Understanding this dynamics is important for public health in countries, where climatic and environmental conditions are favorable for the spread of these diseases. For this reason, models that study the population dynamics in a city are of short importance. This work discusses the numerical modeling of the population dynamics of the mosquito Aedes aegypti in an urban neighborhood of a city. First, we present the preliminary theoretical results of one-dimensional models. Next, we propose a two-dimensional model using partial differential equations. This model allows incorporating external factors (wind and chemical insecticides) and topographic data (streets, building blocks, parks, forests and beaches). The proposed model was tested in examples involving two Brazilian cities (the city center of Juiz de Fora and Copacabana Beach in Rio de Janeiro).
346

Modelagem matemática do aumento de densidade de vegetação na Amazônia e dinâmica populacional com competição intra e interespecífica / Mathematical modeling of the increased density of vegetation in the Amazon competition and population dynamics with inter and intra-specific

Santos, Carlos Frank Lima dos, 1976- 09 May 2013 (has links)
Orientador: João Frederico da Costa Azevedo Meyer / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática Estatística e Computação Científica / Made available in DSpace on 2018-08-23T13:46:24Z (GMT). No. of bitstreams: 1 Santos_CarlosFrankLimados_M.pdf: 3104358 bytes, checksum: a690d16041a50b1c06291d1d64615b29 (MD5) Previous issue date: 2013 / Resumo: O propósito deste trabalho é desenvolver uma modelagem matemática que descreverá computacionalmente o convívio entre duas espécies competidoras sem característica migratória diante da variação de densidade de vegetação. As equações utilizadas nesta modelagem incluíram os fenômenos de difusão de vegetação, processos de dispersão populacional, dinâmicas vitais e um decaimento proporcional a variação de densidade de mata, no sentido de que quanto maior a densidade de mata menor o decaimento populacional quanto menor a densidade de mata maior a mortalidade populacional. Para as espécies competidoras usaremos as clássicas modelagem do tipo Lotka-Volterra (não- linear) combinado a equação diferenciais parciais de difusão-advecção. Primeiramente faremos a descrição do modelo matemático e a descrição do domínio visando o uso do método de diferenças finitas para o espaço combinados a um modelo de Crank-Nicolson no tempo. Em seguida, desenvolveremos um algoritmo em ambiente MATLAB , que aproxima as soluções relativas a difusão de vegetação e a cada população em cada ponto e ao longo do tempo considerado nas simulações. Por fim, foram obtidos resultados gráficos que foram analisados o efeito da recuperação da mata no convívio das espécies competidoras consideradas. De modo que se disponha de ferramentas mais acessíveis a profissionais e pesquisadores ligados aos estudos de ecologia matemática e meio ambiente, bem como aos responsáveis pelas adoções de medidas de emergências e contingências de áreas destruídas pelas ações antrópicas / Abstract: The main objective of this work is that of obtaining an adequate mathematical model and, consequently, a computational algorithm to describe the interaction between two competing species in face of a density variation in vegetation. Population dispersal and dynamics and the presence of a term relating the loss of vegetation density to higher mortality for both competing species must be considered, as well as the inverse: a raise in vegetation density is bound to increase the survival of species. In order to describe the interaction between vegetation and animals, a classic Lotka-Volterra system is used, coupled with the use of the diffusion-reaction partial differential equation for all three participants considered in the model: vegetation density and both animal species. For the interacting animal species, no migration is considered, although the possibility of a preferential direction similar to an advective component is permitted in the dispersal of plants. Numerical discretization include centered finite differences in order to obtain second order approximations in space variables, as well as a Crank-Nicolson method, also second order, for approximations in time. In order to qualitatively analyze possible results, a MATLAB environment was used, with the possibility of exhibiting graphical results based on the numerical ones. This is done in order to create a numerical auxiliary tool which can be used by researchers and professional agents in the evaluation of ecological and environmental policies and decisions, as well as the description of some of the effects of anthropic a actions / Mestrado / Matematica Aplicada / Mestre em Matemática Aplicada
347

Variation génétique et persistance des populations en milieu marin : implications pour la conservation / Genetic variation and population persistence in marine systems : implications for conservation

Dalongeville, Alicia 22 September 2017 (has links)
Les écosystèmes marins sont soumis à des changements environnementaux rapides sous l’impact des pressions anthropiques croissantes qui menacent la persistance des espèces et des populations locales. Comprendre les effets de la variabilité génétique et des capacités de dispersion sur la persistance des espèces marines, est donc un enjeu majeur pour la conservation de la biodiversité. Mes travaux de doctorat répondent ainsi à deux objectifs principaux : (i) évaluer la distribution spatiale et les déterminants de la variation génétique de populations de poissons marins côtiers (ii) estimer les réponses des populations aux changements climatiques afin de mieux comprendre leur capacité de persistance.J’ai d’abord montré, à partir d’une synthèse bibliographique réalisée sur 31 espèces de poissons méditerranéens, que les traits écologiques liés à la mobilité et à la taille des populations influencent fortement le niveau de diversité génétique intra-populationnelle des espèces. Ensuite, j’ai étudié les déterminants de la variation génétique spatiale à partir des données récoltées sur 727 individus de rouget de roche (Mullus surmuletus) issus de 72 sites autour la Mer Méditerranée et regroupés en 47 groupes génotypés pour 1153 marqueurs SNP. Des analyses de génétique du paysage ont montré que la dispersion larvaire structure la variation génétique de l’espèce à moyenne et petite échelle spatiale (<1 000km), alors que l’isolement géographique, possiblement dû à l’histoire démographique des populations ou à l’adaptation, est le principal facteur structurant à plus large échelle. Finalement, l’étude de la variation génétique adaptative de M. surmuletus réalisée à l’aide d’un criblage génomique a mis en évidence une potentielle réponse adaptative de l’espèce au gradient Est-Ouest de salinité en Méditerranée.Dans un second temps, un modèle démo-génétique simulant la dynamique et la résilience des populations de coraux dans l’Indopacifique a montré qu’un mécanisme de « sauvetage évolutif » permet aux génotypes adaptés aux eaux les plus chaudes de diffuser entre les populations grâce à la connectivité larvaire. Ce mécanisme favorise la persistance des populations en permettant leur adaptation à des changements environnementaux qui conduiraient sans cela à des déclins, voir des extinctions locales.Finalement, l’ensemble de ces travaux ont mis en évidence la nécessité de considérer la connectivité et le potentiel évolutif des espèces dans les stratégies de conservation, afin de maximiser leur capacité de résilience et de persistance à long terme en dépit des crises environnementales de plus en plus prononcées. / World marine ecosystems are experiencing unprecedented anthropic pressures inducing rapid environmental changes that threaten the persistence of wild species and their local populations. Hence, understanding the effects of genetic variability and dispersal capacities on marine population persistence is a key issue for the conservation of biodiversity. My PhD work had two main objectives: (i) evaluate the spatial distribution and drivers of genetic variation across coastal marine fish populations, and (ii) estimate the response of populations to climate changes in order to better understand their ability to persist.First, by performing a synthesis of published literature on 31 Mediterranean fish species, I showed that ecological traits related to mobility and population size strongly influence the level of within-population genetic diversity across species. Then, I studied the drivers of spatial genetic variation using genetic data from 727 individuals of the stripped red-mullet (Mullus surmuletus) collected in 72 sites around the Mediterranean Sea, and grouped into 47 pools genotyped for 1153 single nucleotide polymorphism (SNP) markers. Seascape genetic analyses showed that larval dispersal predominantly structures M. surmuletus genetic variation at intermediate and local spatial scales (<1000 km), whereas geographic isolation, due to population demographic history or adaptation, is the main driver at larger spatial scale. Lastly, studying the adaptive genetic variation of M. surmuletus using genome scan revealed a potential adaptive response of this species to the East-West gradient in salinity across the Mediterranean Sea.Subsequently, using a demo-genetic model to simulate coral population dynamics and resilience across the Indo-pacific corals, I showed that the process of ‘evolutionary rescue’ can help genotypes adapted to warm ocean waters to move and migrate between populations thanks to larval connectivity. Evolutionary rescue can thus promote the persistence of populations by allowing them to adapt to environmental changes that would otherwise lead to population declines or even local extinctions.Finally, all of these results highlighted the need to better consider connectivity and the evolutionary potential of species in conservation strategies, in order to maximize their resilience capacity and long-term persistence in the face of more severe environmental crises.
348

Sustainable Whale-watching for the Philippines: A Bioeconomic Model of the Spinner Dolphin (Stenella Longirostris)

Santos, Allison Jenny 10 March 2016 (has links)
Whale-watching provides economic opportunities worldwide and particularly proliferates in developing countries, such as the Philippines. The sustainability of whale-watching is increasingly debated as these activities also negatively impact cetaceans through changes in behavior, communication, habitat use, morbidity, mortality, and life-history parameters. This study evaluated the total annual cost, revenue, and profit of whale-watching operators in Bais, Philippines, and predicted the changes in the population for spinner dolphin Stenella longirostris with varying levels of whale-watching effort. Total revenue was 3,805,077 PHP ($92,478 USD) while total cost was 5,649,094 PHP ($137,294 USD) with a discount rate of ten percent. The total annual profit of whale-watching in Bais was – 1,844,017 PHP (– $44,817 USD). On average, each operator in Bais lost 160,350 PHP ($3,897 USD) per year from whale-watching. Through time, the spinner dolphin population decreased as it was exposed to more vessels, causing effort to increase, and thus decreased profit for operators. Under current whale-watching effort, the spinner dolphin population was predicted to decrease by 94 percent in 25 years. If Bais reduced effort in their operations to only three vessels whale-watching per day, the spinner dolphin population increased to 80 percent of its initial population size. This was the first study to predict the spinner dolphin population and estimate the total annual profit from whale-watching in Bais, Philippines. It provided data to locals for efficient, profitable, and sustainable decisions in whale-watching operations.
349

Mechanismy řídící koexistenci rostlin diploidního a tetraploidního cytotypu v populacích heřmánkovce nevonného (Tripleurospermum inodorum) / Mechanisms driving di- and tetraploid coexistence in mixed-ploidy populations of Tripleurospermum inodorum

Nedomová, Anežka January 2016 (has links)
Genome duplication plays a significant role in plant evolution. Formation of new polyploids is generally considered to be rare. Nevertheless, under natural conditions mixed-ploidy populations occur in relatively large numbers. Only the observations in the cytotype contact zone can identify all the factors affecting the stability or instability of the population. Number of research focusing on study of cytotype coexistence in natural mixed-ploidy populations is still low. As a model system for the study of mechanisms governing cytotype coexistence was chosen the Tripleurospermum inodorum. Research focused on natural mixed-ploidy populations and also on planted mixed-ploidy populations. Permanent plots were located in south, west, northwest and north Bohemia. Field observations were supplemented by cultivation experiments carried out in the greenhouse. Several phenomena were discovered at the level of whole populations. Cytotype distribution in the plot was random. The spatial structure of natural populations was quickly changing even within a single season. Even between single plot evaluations the cytotype ratios varied. Three percent of all plants were triploid hybrids. Most often detected cytotype in soil seed bank was diploid cytotype. The study of population dynamics shows, that tetraploids are...
350

Faktory ovlivňující populační dynamiku kriticky ohroženého druhu Dianthus arenarius subsp. bohemicus / Factors affecting population dynamics of endangered plant species Dianthus arenarius subsp. bohemicus

Sejrková, Petra January 2017 (has links)
This diploma's thesis deals with critically endangered species Dianthus arenarius subsp. bohemicus from family Caryophyllaceae. Its distribution range is now limited on its last natural locality in National natural monument Kleneč. As a result of the change in land use (especially the abandonment of grazing), there was a significant reduction in its population size at the end of the 20th century and it was close to extinction. That is why action plan for species conservation was approved, which included number of management interventions at the locality. The most important was the removal of the upper humus horizon, which aims to create free gaps in the sand that allow the emergence and growth of new plants of D. arenarius subsp. bohemicus. The study species is also attacked by herbivores and it was predicted that increasing population might be endangered with increased herbivore population. The aim of this thesis is therefore to describe the population dynamics of the species, to evaluate the effect of the management and to determine how the herbivory affects the population dynamics of the species. The population growth rate decreases over time with vegetation succession. Even eight years after removal the population is still growing. The population growth rate is most affected by change in...

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