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A study of the abundance, diversity, and recruitment status of freshwater mussels in the Marais des Cygnes River, KansasBradburn, Megan. Rabeni, Charles F. January 2009 (has links)
The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on October 20, 2009). Thesis advisor: Dr. Charles Rabeni. Includes bibliographical references.
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Spatial analysis of Helianthus schweinitzii (Schweinitz's sunflower), an endangered species endemic to the Piedmont of North CarolinaSmith, Tammy Capps. January 1900 (has links)
Thesis (M.A.)--The University of North Carolina at Greensboro, 2008. / Directed by Roy Stine; submitted to the Dept. of Geography. Title from PDF t.p. (viewed Apr. 13, 2010). Includes bibliographical references (p. 58-64).
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Ecology and genetic diversity of Gentiana pannonica populations in different geographical and habitat scales / Ecology and genetic diversity of Gentiana pannonica populations in different geographical and habitat scalesEKRTOVÁ, Ester January 2012 (has links)
The thesis focused to population ecology and genetics of subalpine species Gentiana pannonica. Pollination ecology of species and generative reproduction in different habitat (primary vs. secondary) were investigated in the field. Genetic variation and structure of G. pannonica populations were studied in three disjunct parts of its distribution range: the Eastern Alps, the Bohemian Forest, and the Giant Mts. Present distribution of G. pannonica in the central past of the Bohemian Forest were processed.
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Effects of habitat patch size and isolation on the population structure of two siphonarian limpetsJohnson, Linda Gail January 2011 (has links)
Habitat fragmentation is a fundamental process that determines trends and patterns of distribution and density of organisms. These patterns and trends have been the focus of numerous terrestrial and marine studies and have led to the development of several explanatory hypotheses. Systems and organisms are dynamic and no single hypothesis has adequately accounted for these observed trends. It is therefore important to understand the interaction of these processes and patterns to explain the mechanisms controlling population dynamics. The main aim of this thesis was to test the effect of patch size and isolation on organisms with different modes of dispersal. Mode of dispersal has previously been examined as a factor influencing the effects that habitat fragmentation has on organisms. Very few studies have, however, examined the mode of dispersal of marine organisms because it has long been assumed that marine animals are not directly influenced by habitat fragmentation because of large-scale dispersal. I used two co-occurring species of siphonariid limpets with different modes of dispersal to highlight that not only are marine organisms affected by habitat fragmentation but that they are affected in different ways. The two species of limpet, Siphonaria serrata and Siphonaria concinna, are found within the same habitat and have the same geographic range along the South African coastline, however, they have different modes of dispersal and development. The effect of patch size on organism density has been examined to a great extent with varied results. This study investigated whether habitat patch size played a key role in determining population density and limpet body sizes. The two species are found on the eastern and southern coasts of South Africa were examined across this entire biogeographic range. Patch size was found to have a significant effect on population density of the pelagic developer, S. concinna, but not the direct developing S. serrata. Patch size did play a role in determining limpet body size for both species. S. concinna body size was proposed to be effected directly by patch size whilst S. serrata body size was proposed to be affected indirectly by the effects of the S. concinna densities. The same patterns and trends were observed at five of the seven examined regions across the biogeographic range. The trends observed for S. concinna with respect to patch size conform to the source-sink hypothesis with large habitat patches acting as the source populations whilst the small habitat patches acted as the sink populations. Many previous studies have focused on the effects of habitat patch size at one point in time or over one season. I tested the influence of habitat patch size on the two species of limpets over a period of twelve months to determine whether the trends observed were consistent over time or whether populations varied with time. S. concinna showed a consistently significant difference between small and large patches; whilst S. serrata did not follow a consistent pattern. The mode of dispersal for the two limpets was used to explain the different trends shown by the two species. This examination allowed for the determining of source and sink populations for S. concinna through the examination of fluctuations in limpet body sizes and population densities at small and large habitat patches over twelve months. The direct developing S. serrata trends could not be explained using source-sink theory, as populations were independent from one another. S. serrata demonstrated body size differences at small and large patches which, may be explained by interspecific and intraspecific competition. Habitat isolation is known to play an important role in determining the structure of assemblages and the densities of populations. In this study the population density of the pelagic developing S. concinna showed a weak influence of degree of isolation whilst that of the direct developing S. serrata did not, which may be because of habitat patches along the South African coastline not having great enough degrees of isolation. The population size-structure was influenced directly influenced by isolation for S. concinna, whilst the different population size structure for S. serrata may be explained by assemblage co-dependence. The mode of dispersal showed effects on the relationship of population density and population size-structure with habitat size and isolation. This study indicates the importance of investigating patterns and processes across a range of spatial and temporal scales to gain a comprehensive understanding of factors effecting intertidal organisms.
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Biologia populacional de Callichirus major (Say, 1818) (Crustacea : Axiidea: Callianassidae), nas praias de Santos e São Vicente, litoral centro do Estado de São Paulo, Brasil : subsídios para conservação e manejo /Hereman, Michael José January 2017 (has links)
Orientador: Marcelo Antonio Amaro Pinheiro / Coorientador: Patricio Alejandro Hernáez Bové / Resumo: As praias de Santos (SP) apresentam legislação municipal de proibição de captura das espécies de Callianassidae, p ex. Callichirus major (Lei Municipal nº 1.293/93), fato este não verificado em municípios limítrofes, como São Vicente. Esta legislação foi decorrente de um amplo estudo de 10 anos (1983 a 1993), desde então não existindo outros mais aprofundados sobre a biologia populacional desta espécie. Portanto, a presente dissertação tem como objetivos realizar uma avaliação comparativa da biologia populacional de Callichirus major entre a praia do Gonzaga, localizada no Município de Santos (protegida) e a praia do Itararé, no Município de São Vicente (sem legislação pertinente à captura da espécie). O primeiro objetivo foi efetuar um teste de tamanho do quadrado ideal para as amostragens, através do método de Wigert (W), assim como o número de réplicas por subárea amostral, determinada pela estabilização das variâncias (V), indicando um mínimo ideal de 50 réplicas (V=24,6). O possível efeito da declividade e distância do mar sobre os parâmetros populacionais da espécie foi também testado em duas transecções de quadrados amostrais contíguos (vertical e paralela à linha de costa). Com base nos resultados obtidos, foi estabelecido o número de subáreas amostrais em cada praia, levando-se em conta sua extensão (Praia do Itararé: 2,3 km; e Praia de Santos: 4,7 km). A densidade foi maior nas transecções próximas aos canais (5,0 ± 1,6 e 4,5 ± 2,0 ind./m2) do que aquela mais equidi... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The C. major from Santos (SP) are protected by law (municipal law number 1.293/93) so, it's prohibited to capture this crustacean from the beaches, this fact isn't verified at boundaries counties, just like São Vicente, for example. This legislation was due a great study during 10 years (1983 to 1993), since then, doesn't exist other importants studies about this specie. Therefore, this present dissertation aims to realize a comparative avaliation of the populational biology of Callichirus major between Gonzaga beach (Santos, SP), a protected area, and Itararé beach (São Vicente, SP). The first objective was realize a test to obtain a optimiun quadrat size for the sampling, using the Wigert (W) method, as well as the number of replicates per sample areas, determinate by the stabilization of variances (V), indicating a minimum of 50 replicas (V=24,6). The possible effect of declivity and sea's distance were evaluated too, using for this, two transections of contiguous sample quadrat (vertical and parallel to the coast line), the one with less variance of sazonal and temporal analyzes was chosen. Based in the obtained results, a number of sample areas were established, taking into account the beaches's extension (Itararé's beach: 2,3km; Santos's beach: 4,7 km). The density was bigger at the transections near the channels (5,0 ± 1,6 e 4,5 ± 2,0 ind./m2) then the equidistant one (F = 13,20; p = 0,000), indicating to avoid nearby channels areas to minimize the sampling bias during the spatial analyzes. In both beaches the species's galleries per sample quadrat were calculated, in order to compare the distribution conditions of this animal particularly at these beaches, and the respective data inserted in eletronics spreadsheets, reaching the second objective os this study. In other subarea, at both beaches (Gonzaga e Itararé), specimens of C. major... (Complete abstract electronic access below) / Mestre
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Dinâmica estocástica de populações biológicas / Stochastic Dynamics of Biological PoupulationsFlávia Mayumi Ruziska Hirata 15 August 2017 (has links)
Nesta tese investigamos modelos irreversíveis dentro do contexto da mecânica estatística de não-equilíbrio motivados por alguns problemas de dinâmicas de populações biológicas. Procuramos identificar a existência de transições de fase e as classes de universalidade às quais os modelos pertencem. Além disso, buscamos modelos que capturem as principais características dos sistemas biológicos que procuramos descrever. Encontramos a solução analítica exata para o modelo suscetível-infectado-recuperado (SIR) em uma rede unidimensional. Investigamos o modelo suscetível-infectado-recuperado com infecção recorrente. Mostramos que o modelo pertence à classe de universalidade da percolação isotrópica, salvo pelos parâmetros em que se torna o processo de contato. Obtivemos também a linha de transição entre as fases em que há e não há propagação da epidemia, através de aproximações de campo médio e por simulações de Monte Carlo do modelo na rede quadrada. Investigamos uma dinâmica para duas espécies biológicas e dois nichos ecológicos; para tanto introduzimos um modelo estocástico irreversível de quatro estados. Concluímos que o modelo oferece uma descrição para as oscilações temporais das populações das espécies e para a alternância de dominância entre estas. Para chegar a esta conclusão, utilizamos simulações de Monte Carlo do modelo na rede quadrada, aproximações de campo médio e a abordagem da equação mestra de nascimento e morte, a qual, para grandes populações, pode ser aproximada por uma equação de Fokker-Planck que é associada a um conjunto de equações de Langevin. Por fim, usando simulações de Monte Carlo, analisamos a dinâmica de duas espécies biológicas e dois nichos ecológicos incluindo difusão. Novamente verificamos que o modelo gera cenários com oscilações temporais das populações das espécies e alternância de dominância entre estas. Ademais, concluímos que modelo pertence à classe de universalidade da percolação direcionada e obtivemos o diagrama de fase. / In this thesis we investigate irreversible models within the context of nonequilibrium statistical mechanics motivated by some problems of biological population dynamics. We look for dentifying the existence of phase transition and the universality classes to which the models belong. In addition to that, we look for models that capture the main characteristics of the biological systems which we are interested in describing. We found the exact analytic solution of the susceptible-infected-recovered (SIR) model on one-dimensional lattice. We investigated the susceptible-infected-recovered model with recurrent infection. We showed that the model belongs to the isotropic percolation universality class, except for the parameters that make the model become a contact process. We obtained the transition line between the phases in which there is propagation of the epidemic and in which there is not, by means of mean-field approximations and Monte Carlo simulations on a square lattice. Furthermore, we investigated a dynamic for two biological species and ecological niches; for this purpose we introduced an irreversible stochastic model with four states. We conclude that the modoffers a description of time oscillations of the species populations and of the alternating dominance between them. To achieve this conclusion we used Monte Carlo simulations of this model on a square lattice, mean-field approximation, and the birth and death master equation approach, which for large populations can be approximated by a Fokker-Planck equation that is associated to a set of Langevin equations. Finally, using Monte Carlo simulations, we analyzed a dynamic for two biological species and ecological niches including diffusion. Again, we verified that the model generates scenarios with time oscillations of the species populations and with alternating dominance between them. Also, we conclude that the model belongs to the directed percolation universality class and we found the phase diagram.
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Biologia populacional e fecundidade do anfipode endobionte Leucothoe sp. (Crustacea, Amphipoda, Leucothoidae) associado a Phallusia nigra (Chordata, Tunicata) do Canal de São Sebastião, litoral norte do estado de São Paulo / Population biology and fecundity of Leucothoe sp. (Crustacea, Amphipoda, Leucothoidae) associated to Phallusia nigra (Chordata, Tunicata) from the São Paulo Sebastião, northern of the State of São PauloSiqueira, Silvana Gomes Leite, 1975- 27 February 2007 (has links)
Orientador: Fosca Pedini Pereira Leite / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-09T22:39:00Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: Este estudo teve como objetivo caracterizar a biologia populacional e a fecundidade do gamarídeo Leucothoe sp. associado à ascídia Phallusia nigra no Canal de São Sebastião, Litoral Norte do Estado de São Paulo. A estrutura populacional, crescimento, razão sexual, fecundidade, dimorfismo sexual e mortalidade deste anfípode foram observadas bimestralmente em oito costões do infralitoral e relacionados com a temperatura da água e a biomassa das ascídias. Em cada período e local foram coletadas três ascídias. Indivíduos de todos os estágios de desenvolvimento de Leucothoe sp. foram encontrados associados a P. nigra, caracterizando o ambiente como estável e propício para a sua reprodução e alimentação. A associação não variou no período de estudo, não foi influenciada pela biomassa da ascídia e nem pela temperatura da água. A maior parte da população de Leucothoe sp. foi composta de jovens. O menor número de indivíduos adultos pode estar relacionado a fatores como mortalidade e à busca dos jovens por novos hospedeiros. Os dados referentes à estrutura de tamanho e crescimento indicam que Leucothoe sp. pode viver entre 7,2 e 11 meses caracterizando um ciclo de vida semi-anual. A razão sexual de Leucothoe sp. foi desviada a favor das fêmeas, fato provavelmente relacionado com migração e mortalidade diferencial dos machos. A reprodução de Leucothoe sp. é contínua e a fecundidade está positivamente relacionada com o tamanho do corpo, como é freqüente entre os gamarídeos. Machos e fêmeas de Leucothoe sp. apresentam diferenças morfológicas nos segundos gnatópodo indicando a presença de dimorfismo sexual / Abstract: The aim of this study was to characterize the population biology and the fecundity of the gammaridean amphipod Leucothoe sp. associated to the ascidia Phallusia nigra on the Channel of São Sebastião, situated in the north coast of Estado de São Paulo, analyzing aspects such as population structure, growth, sex-ratio, fecundity, sexual dimorphism and mortality of this amphipod. Every two months, three ascidians had been collected in the sub littoral of eight rocky coasts of the Channel. The results were related with the temperature of the water and the biomass of the ascidian. Individuals of all development stages of Leucothoe sp. had been found associated with the P. nigra, characterizing this host as a steady and propitious environment for its reproduction and feeding. The association did not vary with the study period and wasn¿t influenced by the biomass of the ascidians or by the water temperature. Most of the population of Leucothoe sp. inside P. nigra was composed by juveniles. The reduced number of adults can be related to the increase of mortality and to the exit of the juveniles for searching new hosts. The data related to the population, size structure and growth indicate that Leucothoe sp. can live from 7.2 to 11 months characterizing an semi-annual life cycle. The sex-ratio of Leucothoe sp. was deviated in favor of the females, fact probably related with migration and differential mortality of the males. The reproduction of Leucothoe sp. is continuous and the fecundity is positively related with body size, an usual pattern for gammarideans. Males and females of Leucothoe sp. present sexual dimorphism with morphologic differences in the second gnathopods / Mestrado / Mestre em Ecologia
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Ecologia de populações de Psychotria suterella Mull. Arg. (Rubiaceae) em uma paisagem fragmentada de Mata Atlantica / Population ecology of Psychotria suterella Mull. Arg. (Rubiaceae) in fragmented Atlantic rainforest landscapeBertani, Daniela Fessel 22 February 2006 (has links)
Orientador: Flavio Antonio Maes dos Santos / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-06T06:40:59Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: Existe muita variação no grau de sensibilidade de populações de plantas à diminuição de habitats naturais e poucos estudos em áreas com prioridade de conservação.Este estudo teve como objetivo testar se a descontinuidade e qualidade de habitats de Mata Atlântica afetam a abundância, estrutura, relações alo métricas, dinâmica e germinabilidade de sementes de populações de uma espécie comum de sub-bosque, P_ychotria suterella (Rubiaceae). Foram amostradas nove populações dessa espécie em três áreas em uma floresta contínua, três tTagmentos conectados e três tTagmentos isolados em uma paisagem de Mata Atlântica tTagmentada no estado de São Paulo. A densidade de indivíduos foi menor e a taxa de mortalidade maior nos tTagmentos isolados. Todas as populações apresentaram padrão espacial agrupado, exceto a população de um fragmento isolado, que apresentou distribuição aleatória. As populações de menor tamanho apresentaram maior crescimento em altura e diâmetro, maior taxa de mortalidade e maior taxa de ingresso. Diferenças nas taxas de ingresso entre populações aparentemente não tiveram relação com a germinabilidade de sementes, pois a porcentagem de germinação não diferiu entre populações. A mortalidade aumentou em função do aumento da densidade intraespecífica. o crescimento negativo aumentou com o aumento da porcentagem de danos nos indivíduos. Indivíduos de classes de tamanho diferentes parecem ter sido afetados de forma oposta aos fatores analisados. Quanto menor o tTagmento, maior a abertura do dossel e o grau de perturbação antrópica, maior a proporção de indivíduos menores e menor a proporção de indivíduos de maior tamanho. Indivíduos menores apresentaram maior taxa de mortalidade e maior crescimento, quando comparados a indivíduos maiores. Em escala menor a disponibilidade de luz e a densidade afetaram as relações alométricas (diâmetro x altura) dos indivíduos. Em maior escala, populações com baixa densidade de indivíduos e sujeitas a maior luminosidade variam muito na forma de crescimento. Todas as populações apresentaram declínio populacional. As taxas de crescimento populacional ()v) variaram entre as áreas e no tempo, sendo que para a maioria das populações "A foi menor que 1. As classes de estase contribuíram mais para os valores de "A. As contribuições de transições para mudança de classe de tamanho (crescimento e regressão) apresentaram pouca contribuição à "A As taxas de crescimento populacional ("A) não diferiram entre as populações da floresta contínua e dos fragmentos. As contribuições para 11"A na estase variaram muito entre os anos amostrados. Existiu maior probabilidade nos fragmentos, de indivíduos passarem para uma classe de maior tamanho, e maior probabilidade na floresta contínua de indivíduos regredirem de tamanho. A combinação de diferentes fatores pode alterar a abundância e estrutura de populações de Psychotria sute re lia, e em situações extremas essas alterações podem ser negativas. A grande variação no tempo das taxas de dinâmica podem sugerir estocasticidade demográfica, e o declínio populacional lento das populações na paisagem podem indicar a possibilidade a longo prazo de extinção de algumas populações / Abstract: There is wide variation in the sensibility levei of plant populations to the decrease of their natural habitats. There are also few studies in priority conservation areas. The objective of this study is to test if the discontinuity and quality of the Atlantic Rainforest affect the structure, alometric relations, dynamics, and seed germinability of the populations of a common understory specie, Psychotria suterella (Rubiaceae). Nine populations of the species were sampled in three areas of continuous forests, three connected fragments, and three isolated fragments, in a landscape of fragmented Atlantic Rainforest in São Paulo State, southeastern Brazil. The density of individuais was smaller and the mortality rate of the isolated fragments was higher. All the populations presented a clustered spatial pattern except for a population of one isolated fragment which presented random distribution. The smaller populations presented higher growth, higher mortality rate, and higher recruitment rate. The ditTerences found in the recruitment rates between the populations have no apparently relation with the seeds germination. The germination percentage was not different among the populations. Mortality increased because the intraspecific density also increased. The negative growth increased with the increase of the damage percentage in the individuais. lndividuals of different size class appeared to be affected in the opposite way to the analyzed factors. The proportion of small individuais was higher according to a decrease on the size of the fragment, on increase of the canopy openness, and antropic disturbance. lt worked opposite with larger individuais. Smaller individuais presented a higher mortality rate and higher growth when compared to bigger individuais. ln small scale the density and light conditions affect the alometric relations of individuaIs. ln large scaIe populations with Iow density of individuaIs and higher light conditions may vary a lot in their way of growth. Ali the popuIations presented populational decline. The populations growth rate (À.) varied among areas and in time. For the majority of populations À. was less than 1. The stasis class contributed to the À. values. The contributions of transitions for the change of size class (growth and regression) presented little contribution to À.. The populational growth rate (À.) did not differ among the continuous forest populations and the fTagments. The contribution to /).À. in stasis varied considerably among the sampled years. In the fTagments there was higher probability of individuaIs to get to a class of larger size. In the continuous forest there was higher probability of individuaIs to decrease in size. The combination of different factors may alter the abundance and structure of the Psychotria sllterella populations. In extreme situations these alterations may be negative. The wide variation in time of the dynamics rate may show demographic stocasticity. The slow populational decline of the populations in the landscape may indicate the possibility of extinction of some populations in the long termo / Doutorado / Doutor em Biologia Vegetal
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Historia natural e biologia populacional de Phloeophana longirostris Spinola 1847 (Heteroptera: Phloeidae) na Serra do Japi, Jundiai, SP / Natural history and population biology of Phloeophana longirostris Spinola 1837 (Heteroptera: Phloeidae), in Serra do Japi, Jundiai, SPPostali, Thais Cifuentes 12 August 2018 (has links)
Orientador: João Vasconcellos Neto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-12T20:53:18Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: Phloeophana longirostris e uma especie de percevejo pertencente aos Phloeidae, uma pequena familia de insetos tropicais. Sao organismos de habito fitofago, que vivem camuflados sobre o tronco de suas plantas hospedeiras, se assemelhando a liquens. Esse trabalho reune, com base em dezoito meses de estudo na Serra do Japi, observacoes naturalisticas da historia natural e biologia da especie. Tambem foram investigadas a estrutura e a biologia populacional de P. longirostris, e se ha correlacao dos parametros populacionais com os fatores climáticos precipitação e temperatura. Os individuos de P. longirostris foram encontrados em areas de mata, somente sobre arvores de Croton floribundus Spreng (Euphorbiaceae), em locais com ocorrencia de liquens. Sua defesa e primariamente baseada em sua camuflagem nas arvores hospedeiras, e formigas Crematogaster spp. foram os principais predadores de P. longirostris ao longo do estudo. A especie apresenta cuidado maternal, com a protecao dos ovos e das ninfas, que ficam sob o abdomen materno ate pouco depois da primeira ecdise. O crescimento das ninfas e lento, e estas apresentam cinco instares ate atingirem a fase adulta. Na fase adulta ha dimorfismo entre machos e femeas, e as femeas sao maiores que os machos. A estrutura da populacao de P. longirostris variou ao longo do estudo, e a especie apresentou um padrão sazonal, com o periodo reprodutivo ocorrendo na estacao quente e chuvosa. A abundancia de individuos nao foi correlacionada a precipitacao total mensal e a temperatura media mensal. Houve somente correlacao entre a abundancia de individuos e o instar de desenvolvimento em todos os meses. A distribuicao vertical de ninfas e adultos tambem nao foram relacionados a precipitacao total mensal e a temperatura media mensal. Os adultos apresentaram distribuição vertical superior a das ninfas. Esse foi o primeiro estudo sobre a historia natural e ecologia de P. longirostris. / Abstract: Phloeophana longirostris is a true-bug species which belongs to the Phloeidae, a small family of tropical insects. It is a lichen-like phytophagous species which lives camouflaged on its host plants' trunk. This study presents information on this species biology, natural history and naturalistic observations gathered during an eighteen-month study in Serra do Japi. P. longirostris population biology was also investigated specially regarding the correlation between population parameters with climatic factors such as temperature and rainfall. The P. longirostris individuals were found only in forest areas, exclusively on Croton floribundus Spreng (Euphorbiaceae) trees, in sites where lichens also occurred. This species main defense is the camouflage on its host tree. Crematogaster spp. (Formicidae) were P. longirostris' main predators during the study. This species presents maternal care with the protection of eggs and nymphs, which remain under the female's abdomen a bit after the first molt. The nymphs' growth is slow and presents five instars before the adult stage. In the adult stage there is sexual dimorphism between male and female individuals, and females are bigger than males. P. longirostris' population structure was variable throughout the study and presented a seasonal pattern, with the reproductive period in Serra do Japi's rainy season. The individuals' abundance was not correlated with the total monthly precipitation and with the average temperature. There was only a correlation between the individuals' abundance and the development instar in all of the months considered. The vertical distribution of nymphs and adults was not related too with the total monthly precipitation and with the average temperature. The adult individuals presented a superior vertical distribution in relation to the nymphs. This was the first study on P. longirostris' ecology and natural history. / Mestrado / Mestre em Ecologia
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Pollination, Herbivory, and Habitat Fragmentation: Their Effects on the Reproductive Fitness of Angadenia berteroi, a Native Perennial Plant of the South Florida Pine RocklandsBarrios Roque, Beyte 27 March 2015 (has links)
Angadenia berteroi is a tropical perennial subshrub of the pine rocklands with large yellow flowers that set very few fruits. My dissertation seeks to elucidate the factors that affect the reproductive fitness of Angadenia berteroi a native species of the south Florida pine rocklands. I provide novel information on the pollination biology of this native species. I also assess the effects of herbivory on growth and the reproductive success of A. berteroi. Finally, I elucidate how habitat fragmentation and quality are correlated with reproductive fitness of this native perennial plant.
Using a novel experimental approach, I determined the most effective pollinator group. I used nylon fishing line of widths corresponding to proboscis diameter of the major groups of visitors to examine pollen removal and deposition. In the field, I estimated visitation frequency and efficacy of each pollinator type. Using potted plants, I exposed flowers to single visit from different types of pollinators to measure fruit set. I performed artificial defoliation with scissors on plants growing in the greenhouse to assess the effects of defoliation before flowering as well as during flowering. Additionally, I used structural equation modelling (SEM) to elucidate how A. berteroi reproductive fitness was affected by habitat fragmentation and quality.
My experiments provide evidence that Angadenia berteroi is specialized for bee pollination; though butterflies, skippers and others also visit its flowers, A. berteroi is exclusively pollinated by two native bees of the South Florida pine rocklands . This research also demonstrated that herbivory by the oleander moth may have direct and indirect effects on Angadenia berteroi growth and reproductive success. The SEM results suggested that habitat quality (litter depth and subcanopy cover) may favor reproduction in native species of the South Florida pine rocklands that are properly maintained by periodic fires and exotic control. Insights from this threatened and charismatic species may provide impetus to properly manage remaining pine rocklands in South Florida for this and other endemic understory species.
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