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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.
11

Geographic and temporal variation in the genetic mating systems of pipefish

Mobley, Kenyon Brice 02 June 2009 (has links)
Understanding the processes that govern mating behaviors is a fundamental goal of evolutionary biology and behavioral ecology. Population-level patterns of mate acquisition and offspring production, otherwise known as the genetic mating system, play a central role in the sexual selection on morphological and behavioral traits and may facilitate speciation. The central hypothesis of this research is that variation in environmental conditions, such as temperature, turbidity, and habitat, and demographic influences such as population density, sex ratios and temporal availability of mates, may limit mating and reproductive success in a predictive manner. Therefore the goal of this dissertation is to examine the contributions of geographic and temporal variation on the plasticity of the genetic mating system in two species of pipefish. The first study examined whether meaningful variation in the genetic mating system exists between two natural populations of the dusky pipefish, Syngnathus floridae. Results of this investigation provide evidence that the genetic mating system differs among different geographic locations. The second study considered the relative contributions of environmental conditions and population demographics on differences in the genetic mating system of dusky pipefish from five natural populations. The results of this investigation show strong trends for demographic and environmental factors to strongly influence the genetic mating system between populations. The third study considered how variation in the number of available mates predicts the outcome of sexual selection during the course of a breeding season in the broad-nosed pipefish, Sygnathus typhle. The results of this study indicate a strong influence of the operational sex ratio on the genetic mating system. In addition to these studies, a study was conducted to investigate whether phylogeographic relationships may be responsible for geographic variation in the genetic mating system of the dusky pipefish of pipefish. Mitochondrial DNA analysis does not substantiate subspecies designations for this species and microsatellite analysis show a clear pattern of isolation by distance. Taken together, these studies significantly enhance the understanding of how mating systems are organized over broad environmental gradients and temporal/spatial scales and to the evolution of sexual selection on the whole.
12

Geographic and temporal variation in the genetic mating systems of pipefish

Mobley, Kenyon Brice 02 June 2009 (has links)
Understanding the processes that govern mating behaviors is a fundamental goal of evolutionary biology and behavioral ecology. Population-level patterns of mate acquisition and offspring production, otherwise known as the genetic mating system, play a central role in the sexual selection on morphological and behavioral traits and may facilitate speciation. The central hypothesis of this research is that variation in environmental conditions, such as temperature, turbidity, and habitat, and demographic influences such as population density, sex ratios and temporal availability of mates, may limit mating and reproductive success in a predictive manner. Therefore the goal of this dissertation is to examine the contributions of geographic and temporal variation on the plasticity of the genetic mating system in two species of pipefish. The first study examined whether meaningful variation in the genetic mating system exists between two natural populations of the dusky pipefish, Syngnathus floridae. Results of this investigation provide evidence that the genetic mating system differs among different geographic locations. The second study considered the relative contributions of environmental conditions and population demographics on differences in the genetic mating system of dusky pipefish from five natural populations. The results of this investigation show strong trends for demographic and environmental factors to strongly influence the genetic mating system between populations. The third study considered how variation in the number of available mates predicts the outcome of sexual selection during the course of a breeding season in the broad-nosed pipefish, Sygnathus typhle. The results of this study indicate a strong influence of the operational sex ratio on the genetic mating system. In addition to these studies, a study was conducted to investigate whether phylogeographic relationships may be responsible for geographic variation in the genetic mating system of the dusky pipefish of pipefish. Mitochondrial DNA analysis does not substantiate subspecies designations for this species and microsatellite analysis show a clear pattern of isolation by distance. Taken together, these studies significantly enhance the understanding of how mating systems are organized over broad environmental gradients and temporal/spatial scales and to the evolution of sexual selection on the whole.
13

Assemblages of epibenthic shrimps in coastal waters off Southwestern Taiwan

Chen, Hsu-sen 13 July 2006 (has links)
This study is aiming to investigate the distribution of epibenthic shrimp communities in relation to the environmental factors of their habitats in the coastal sandy bottom of southwestern Taiwan. Shrimp samples were collected from April 2002 to July 2003, with a beam trawl operated at seven stations along the coasts. Simultaneously, water temperature, salinity, dissolved oxygen were measured and sediments were collected. Particle size and organic matter of the sediments were then analyzed in the laboratory. The results of PCA analyses on these environmental factors revealed that the observations could be segregated into two groups along the PC1, representing rainy season with high temperature, low salinity and dry season with low temperature, high salinity, respectively. The observations with coarse particle (>0.125 mm), representing samples from north sites, were found to distribute in the upper part of the PC2; while those with fine particle (<0.125 mm), representing samples from south sites, distributed in the lower part. In total, 15,591 individuals of shrimp were collected, including 20 genus, 39 species. Metapenaeopsis palmensis (88.2%), Trachysalambria curvirostris (3.6%), M. barbata (3.5%) and Parapenaeopsis cornuta (1.4%) were the four dominant species. Significant differences in the spatial distribution were due to the different composition of the dominant species. Although M. palmensis was the most abundant species in most stations, its percentage abundance was the lowest at Fangliao and Jiading, where the dominant species were T. curvirostris for the former and M. barbata and P. cornuta for the latter. Species preferences for various combinations of environmental variables are responsible for shifts in the structure and overall abundance of assemblages and dictated some patterns. Higher abundances of T. curvirostris, Trachypenaeus granulosus, and Solenocera koelbeli were associated with the appearance of high temperature, low salinity and very fine sand, representing the environmental features of Fangliao and Linbian during the rainy season. Stenopus hispidus, Metapenaeus moyebi, Metapenaeus ensis and M. palmensis were abundant coinciding with low temperature, high salinity and high silt and clay that reflecting the dry season of Linyuan and Linbian waters. Metapenaeopsis dalei and M. barbata appeared in large numbers at habitats with high temperature, low salinity and coarse sand, which mainly occurred in Zouying to Jhongjhou during the rainy season. Moreover, Scyllarus rugosus and Parapenaeopsis cornuta seemed to prefer coarse sandy bottom mainly distributed from Jiading to Linyuan. Temporal fluctuations were associated with the population dynamic of the dominant species. The abundance was reduced while the M. palmensis migrated to open sea in late summer and early autumn. As the juveniles of M. palmensis and M. barbata back to the inshore waters, the abundance were increased and reached the peak in spring. Because of the limited distribution, T. curvirostris and P. cornuta were not influence the overall temporal fluctuations but the local fluctuations. Overall, temporal fluctuations act more at a specific level even structural one, and may be linked to some particular stages of the benthic shrimp life cycle, but do not significantly influence the spatial organization.
14

Temporal and Spatial Variation of Gaseous Air Pollutants Monitored at Inland and Offshore Sites in Kao-Ping Area

Su, Ming-min 11 September 2007 (has links)
Air quality was influenced by many factors, in South Taiwan, air pollutants transportation caused by monsoon or sea-land breeze that may caused high air pollution events. Air pollutant generated by human activity on daytime, then transported and accumulated at sea region by land breeze during the nighttime. Unfortunately, air pollutants that accumulated over sea on night may transport back to land by sea breeze on daytime. Besides, monsoon may carry air pollutants from other regions to South Taiwan and caused high air quality event. Till now, air quality influenced by sea-land breeze and monsoon were not verified in South Taiwan. This study investigated the temporal variation and spatial distribution of air pollutants in the atmosphere around the coastal region of South Taiwan. Ambient air pollutants were simultaneously monitored both inland and offshore. Inland monitoring was conducted at two sites associated with fourteen national air quality monitoring stations, while offshore monitoring was conducted at two sites both in an island and on the boat. A protocol of ambient air quality monitoring was conducted for forty-eight hours. Gaseous air pollutants (i.e. CO, SO2, NOX, THC, and O3) were continuously monitored instrumentally. Data obtained from both inland and offshore monitoring were applied to plot the concentration contour by a software SURFER. Hourly variation of air pollutant concentrations was further used to study the influences of sea-land breezes on the transportation of air pollutants around the coastal region of South Taiwan for different seasons. In August and November, 2006 and May, 2007, sea-land breeze was observed during sampling period and sea breeze arise from 9:00 A.M. to 24:00 P.M. The average wind velocity was 1~4 m/s during the sampling period. In January and March, 2007, prevail wind direction was north direction and northeast direction (270o~30o), that was influenced by northeast monsoon during the sampling period. The average wind velocity was 2~4 m/s. The results showed that distribution of air pollutants, including O3, NOX, THC, and CO influenced by sea-land breezes, particularly for ozone. Air pollutants transported to sea region during the nighttime, and transported back at daytime. This phenomenon cause air pollutants accumulated between Kao-Ping and sea region. In general, NOX generated by transportation and industrial process, thus high concentration of NOX appeared during traffic congestion period and at industry region, mainly Kaohsiung city and Linyuang industrial region. However, sea-land breeze effect upon transportation of air pollutants wasn¡¦t obvious for SO2. High SO2 concentration appeared at Linyuang industrial region and Siaogang at daytime, and transported to region along the coast. During northeastern monsoon season, northeast winds obstructed by Central Mountain Range cause air pollutants accumulated at Kao-Ping region. High NOX concentration appeared at Kaohsiung City and Linyuang industrial region. SO2 accumulated at Siaogang and Linyuang during the nighttime might be caused by high atmospheric pressure system and blew air pollutants to Linbian. CO was accumulated at Siaogang at daytime and transported to Donggang, while THC was accumulated at Donggang whole day.
15

Temporal Variations And Sources Of Organic Pollutants In Two Urban Atmopsheres: Ankara And Ottawa

Oguz Kuntasal, Oznur 01 May 2005 (has links) (PDF)
This study aimed at providing a thorough understanding of temporal and spatial variations of VOCs and underlying factors in different microenvironments in two different urban atmospheres, with different degrees of regulatory enforcement. The VOC data were collected in field campaigns conducted in Ankara, Turkey, and Ottawa, Canada over the years 2000-2004. Insight into the sources of VOCs in different urban atmospheres was sought by using three commonly used receptor models namely / Positive Matrix Factorization (PMF), Chemical Mass Balance (CMB) Model and Conventional Factor Analysis (CFA). Motor vehicle related source profiles were developed to use in receptor modeling. Motor vehicles are the most abundant VOC sources with about 60% and 95% contributions to ambient levels in Ankara and Ottawa, respectively. Residential heating (31%) during winter season, biogenic (9%) and architectural coating (12%) emissions during summer season and solvent use (about 12%) emissions are the next abundant VOC sources in Ankara. In addition, a new method to estimate the contribution of sources from wind sectors in urban atmosphere was developed and implemented in this study. The comparison of the results of these two cities demonstrated the influence of control measures on ambient levels and sources of VOCs observed in different urban atmospheres. VOC levels in Ankara exceed EU levels and they are about factor of two higher than that are measured in Ottawa owing to lack of implementation of emission control regulations for VOCs in Ankara compared to well adopted regulations in Ottawa.
16

Variação temporal da comunidade zooplantônica em arroios impactados por mineração na bacia hidrográfica do Arroio Candiota, RS, Brasil

Fernandes, André Pereira Teixeira January 2017 (has links)
A bacia hidrográfica do Arroio Candiota está situada no sudoeste do Estado do Rio Grande do Sul, Brasil. Sofre intensa atividade antrópica, como mineração de carvão e calcário, pecuária, silvicultura e agricultura. Apresenta ainda em seu território a Usina Termelétrica Presidente Médici - UTPM - Candiota II. Este trabalho teve como objetivo analisar a variação temporal da comunidade zooplanctônica, representada por Rotifera, Cladocera e Copepoda, a partir das variáveis ambientais e atributos funcionais em alguns arroios impactados pelos diferentes usos da bacia hidrográfica do Arroio Candiota. Foram realizadas coletas trimestrais de água e zooplâncton com o intuito de caracterizar as estações climáticas do ano, durante o período de abril/2007 a outubro/2014. As coletas ocorreram em sete estações amostrais diferentes, totalizando 161 unidades amostrais. As variáveis físicas e químicas selecionadas para este trabalho foram pH, turbidez, ferro dissolvido, oxigênio dissolvido e temperatura. Para as análises estatísticas foram utilizados modelos lineares generalizados (GLM), cálculo da diversidade das espécies, que envolveu duas medidas baseadas em distâncias topológicas, a distinção taxonômica (Δ*) e a diversidade taxonômica (Δ), análise de espécies indicadoras (ISA) e análise de atributos indicadores (ITA). Foram identificados 152 táxons ao total das coletas. Rotifera foi predominante com 122 espécies, após Cladocera com 16 espécies e Copepoda com 14 espécies. Os resultados mostraram que o pH foi a única variável que apresentou resultado significativo com valores positivamente proporcionais para a abundância de espécies. Em relação à riqueza de espécies, as variáveis pH, ferro dissolvido e oxigênio dissolvido influenciaram positivamente ao longo do tempo. O cálculo da diversidade e distinção taxonômica demonstrou que das 161 unidades amostrais, 127 mostraram valores de diversidade conforme o esperado ao acaso na natureza. Quatro unidades amostrais apresentaram valores da diversidade acima do esperado e 31 exibiram valores abaixo do esperado ao acaso. A ISA identificou duas espécies indicadoras da estação amostral 1 e cinco espécies indicadoras da estação amostral 2. Foram encontradas cinco espécies indicadoras específicas do inverno, cinco do outono, quatro da primavera e nove espécies indicadoras no verão. A ITA demonstrou que espécies de tamanho C4 (≥ 1000 μm), tiveram maior ocorrência no inverno e primavera. O atributo funcional “coletores e raspadores” foi considerado indicador para as estações amostrais EA1 e EA3 por cinco espécies. Os resultados encontrados não demonstraram um gradiente contínuo de crescimento ou declínio da abundância e riqueza de espécies ao longo do tempo. Assim, a comunidade zooplanctônica parece ser mais fortemente influenciada pelas características naturais de Candiota, como relevo e rede de drenagem, com exceção dos riachos que recebem diretamente efluentes da mineração de carvão. / The Arroio Candiota watershed is located in the southwestern state of Rio Grande do Sul, Brazil. It suffers intense human activity, such as mining of coal and limestone, livestock, forestry and agriculture. It also presents in its territory the Thermoelectric Plant Presidente Medici - UTPM - Candiota II. This study aimed to analyze the temporal variation of zooplankton community, represented by Rotifers, Cladocera and Copepoda, from the environmental variables and functional attributes in some streams impacted by different uses of the Arroio Candiota watershed. Quarterly sampling of water and zooplankton were conducted in order to characterize the seasons of the year, during the period April/2007 to October/2014. The collections occurred in seven different sampling stations, totaling 161 sampling units. The physical and chemical variables selected for this study were pH, turbidity, dissolved iron, dissolved oxygen and temperature. For statistical analysis we used generalized linear models (GLM), calculating the diversity of species, which involved two measures based on topological distances, the taxonomic distinction (Δ*) and taxonomic diversity (Δ), indicator species analysis (ISA) and indicators atributes analysis (ITA). There were identified 152 taxa to the total collections. Rotifera was predominant with 122 species, 16 species of Cladocera and 14 species of Copepoda. The results showed that pH was the only variable that showed significant results with positive values proportional to the abundance of species. The variables pH, dissolved iron and dissolved oxygen positively influenced the richness of species over time. The calculation of diversity and taxonomic distinction showed that of the 161 sampling units, 127 showed diversity of values as expected at random in nature. Four sampling campaigns showed values of diversity than expected and 31 showed values lower than expected by chance. The ISA has identified two indicator species of the sampling station 1 and 5 indicator species of sampling station 2. We found five specific indicator winter species, five in autumn, four in spring and nine summer indicator species. The ITA has shown that species of C4 size (≥ 1000 μm), were more frequent in winter and spring. The functional attribute "collectors and scrapers" was considered indicator for the sampling stations 1 and 3 with five species. The results did not demonstrate a continuous gradient of growth or decline in abundance and species richness over time. Thus, the zooplankton community seems to be more strongly influenced by Candiota natural features like topography and drainage network, except for streams that receive wastewater directly from coal mining.
17

Variação temporal da comunidade zooplantônica em arroios impactados por mineração na bacia hidrográfica do Arroio Candiota, RS, Brasil

Fernandes, André Pereira Teixeira January 2017 (has links)
A bacia hidrográfica do Arroio Candiota está situada no sudoeste do Estado do Rio Grande do Sul, Brasil. Sofre intensa atividade antrópica, como mineração de carvão e calcário, pecuária, silvicultura e agricultura. Apresenta ainda em seu território a Usina Termelétrica Presidente Médici - UTPM - Candiota II. Este trabalho teve como objetivo analisar a variação temporal da comunidade zooplanctônica, representada por Rotifera, Cladocera e Copepoda, a partir das variáveis ambientais e atributos funcionais em alguns arroios impactados pelos diferentes usos da bacia hidrográfica do Arroio Candiota. Foram realizadas coletas trimestrais de água e zooplâncton com o intuito de caracterizar as estações climáticas do ano, durante o período de abril/2007 a outubro/2014. As coletas ocorreram em sete estações amostrais diferentes, totalizando 161 unidades amostrais. As variáveis físicas e químicas selecionadas para este trabalho foram pH, turbidez, ferro dissolvido, oxigênio dissolvido e temperatura. Para as análises estatísticas foram utilizados modelos lineares generalizados (GLM), cálculo da diversidade das espécies, que envolveu duas medidas baseadas em distâncias topológicas, a distinção taxonômica (Δ*) e a diversidade taxonômica (Δ), análise de espécies indicadoras (ISA) e análise de atributos indicadores (ITA). Foram identificados 152 táxons ao total das coletas. Rotifera foi predominante com 122 espécies, após Cladocera com 16 espécies e Copepoda com 14 espécies. Os resultados mostraram que o pH foi a única variável que apresentou resultado significativo com valores positivamente proporcionais para a abundância de espécies. Em relação à riqueza de espécies, as variáveis pH, ferro dissolvido e oxigênio dissolvido influenciaram positivamente ao longo do tempo. O cálculo da diversidade e distinção taxonômica demonstrou que das 161 unidades amostrais, 127 mostraram valores de diversidade conforme o esperado ao acaso na natureza. Quatro unidades amostrais apresentaram valores da diversidade acima do esperado e 31 exibiram valores abaixo do esperado ao acaso. A ISA identificou duas espécies indicadoras da estação amostral 1 e cinco espécies indicadoras da estação amostral 2. Foram encontradas cinco espécies indicadoras específicas do inverno, cinco do outono, quatro da primavera e nove espécies indicadoras no verão. A ITA demonstrou que espécies de tamanho C4 (≥ 1000 μm), tiveram maior ocorrência no inverno e primavera. O atributo funcional “coletores e raspadores” foi considerado indicador para as estações amostrais EA1 e EA3 por cinco espécies. Os resultados encontrados não demonstraram um gradiente contínuo de crescimento ou declínio da abundância e riqueza de espécies ao longo do tempo. Assim, a comunidade zooplanctônica parece ser mais fortemente influenciada pelas características naturais de Candiota, como relevo e rede de drenagem, com exceção dos riachos que recebem diretamente efluentes da mineração de carvão. / The Arroio Candiota watershed is located in the southwestern state of Rio Grande do Sul, Brazil. It suffers intense human activity, such as mining of coal and limestone, livestock, forestry and agriculture. It also presents in its territory the Thermoelectric Plant Presidente Medici - UTPM - Candiota II. This study aimed to analyze the temporal variation of zooplankton community, represented by Rotifers, Cladocera and Copepoda, from the environmental variables and functional attributes in some streams impacted by different uses of the Arroio Candiota watershed. Quarterly sampling of water and zooplankton were conducted in order to characterize the seasons of the year, during the period April/2007 to October/2014. The collections occurred in seven different sampling stations, totaling 161 sampling units. The physical and chemical variables selected for this study were pH, turbidity, dissolved iron, dissolved oxygen and temperature. For statistical analysis we used generalized linear models (GLM), calculating the diversity of species, which involved two measures based on topological distances, the taxonomic distinction (Δ*) and taxonomic diversity (Δ), indicator species analysis (ISA) and indicators atributes analysis (ITA). There were identified 152 taxa to the total collections. Rotifera was predominant with 122 species, 16 species of Cladocera and 14 species of Copepoda. The results showed that pH was the only variable that showed significant results with positive values proportional to the abundance of species. The variables pH, dissolved iron and dissolved oxygen positively influenced the richness of species over time. The calculation of diversity and taxonomic distinction showed that of the 161 sampling units, 127 showed diversity of values as expected at random in nature. Four sampling campaigns showed values of diversity than expected and 31 showed values lower than expected by chance. The ISA has identified two indicator species of the sampling station 1 and 5 indicator species of sampling station 2. We found five specific indicator winter species, five in autumn, four in spring and nine summer indicator species. The ITA has shown that species of C4 size (≥ 1000 μm), were more frequent in winter and spring. The functional attribute "collectors and scrapers" was considered indicator for the sampling stations 1 and 3 with five species. The results did not demonstrate a continuous gradient of growth or decline in abundance and species richness over time. Thus, the zooplankton community seems to be more strongly influenced by Candiota natural features like topography and drainage network, except for streams that receive wastewater directly from coal mining.
18

Variações nictemerais e sazonais na estrutura da comunidade fitoplanctônica num sistema de lagoas de estabilização (Novo Horizonte, SP) / Seasonal and diary cycle variations in phytoplankton structure in waste stabilization ponds (Novo Horizonte, SP)

Danielli Cristina Granado 19 March 2004 (has links)
O presente estudo visou caracterizar as variações nictemerais e sazonais na estrutura da comunidade fitoplanctônica do sistema australiano de lagoas de estabilização, localizado no município de Novo Horizonte, SP, por meio de análises de abundância, biomassa, densidade, riqueza e de índices de diversidade, dominância e equidade. Para a realização desse objetivo, as amostras foram coletadas nas lagoas facultativa 1 e facultativa 2 e no efluente final, em quatro épocas: maio/2002 – outono, agosto/2002 – inverno, novembro/2002 – primavera e fevereiro/2003 – verão, a cada seis horas, durante vinte e quatro horas, no total de cinco amostragens (t0, t1, t2, t3 e t4), com início aproximadamente às 9:30 horas; com exceção do efluente final, que foi coletado apenas em t0 e t4. Nestes dois horários também foram coletadas amostras na entrada e na saída da lagoa anaeróbia, para avaliação da eficiência do sistema. Além das variáveis biológicas foram realizadas análises de material em suspensão, nutrientes (nitrogênio total e amoniacal, nitrito, nitrato, fósforo e ortofosfato), oxigênio dissolvido, pH, condutividade elétrica da água, DBO e transparência da água. Foram encontrados organismos pertencentes às classes Chlorophyceae, Cyanophyceae, Euglenophyceae e Bacillariophyceae. Chlorophyceae foi a que mais contribuiu para a riqueza, densidade e biomassa em quase todos os períodos de estudo; mais de 40% da riqueza foi representada por ela e sua maior densidade foi registrada a 0,7 m de profundidade na lagoa facultativa 1, em t3, no inverno (875.834,7 org/ml). Entre as espécies dessa classe, a predominante, em todas as épocas de coleta, foi Chlorella vulgaris, considerada dominante no inverno e abundante nas demais estações. Os outros organismos, no entanto, foram somente comuns, ocasionais ou raros. Apesar de ter sido observada estratificação térmica em alguns horários de coleta, principalmente em t1 (por volta das 15:00h), esta não foi duradoura, talvez por se tratar de um sistema raso. Portanto, pode-se considerar que o ambiente manteve-se homogêneo em relação à comunidade algal ao longo da coluna de água / The aim of this study were to characterize the seasonal and diary cycle variations of the phytoplankton in waste stabilization ponds from Novo Horizonte, SP. The sample were collected in 1 and 2 facultative ponds and effluent in four times: may/2002 – autumn, august/2002 – winter, november/2002 – spring, february/2002- Summer, each six hours in cycle diary. Were analysed abundance, biomass, densith, wealth and diversity index of phytoplankton, chlorophyll a, pheopigments, suspended solids, nutrients, dissolvid oxygen, pH, biochimical oxygen demand, electric conductivity and water’s transparence. The groups meet were: Chlorophyceae, Cyanophyceae, Euglenophyceae and Bacillariophyceae. Chlorophyceae contribute with bigger wealth, density and biomass; of the kinds this group, Chlorella vulgaris, were prevalent, recognized since dominant in the winter and abundant in others seasons. The other organisms, however, were commons, occasionalls or rares. The environment of ponds remain homogeneous in relation to the algal community
19

INFLUÊNCIA TEMPORAL NA CONSTITUIÇÃO MINERAL DE ALGUMAS ESPÉCIES DA FLORA BRASILEIRA / TEMPORAL INFLUENCE ON THE MINERAL COMPOSITION OF SOME SPECIES OF THE BRAZILIAN FLORA

Dolwitsch, Carolina Bolssoni 23 July 2015 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Many plants are widely used for medicinal purposes, especially in Brazil. The chemical composition of these plants arises from the environmental characteristics under which they are grown. Lately, researches have drawn attention to the inorganic composition evaluation of these matrices, since minerals might present either nutritional or toxic character. Hence, the objective of this work was to obtain the mineral composition in terms of essential and non-essential inorganic constituents for three sampling years of Amazonian species grown in Belém/PA: Cecropia palmata, Cecropia obtusa, Bauhinia variegata L., Bauhinia variegata L. var. alboflava, Mansoa alliacea and Connarus perrottetti var. angustifolius. The analitycal technique used was Atomic Absorption Spectrometry. All species showed essential minerals contents above recommended daily intake, indicating they may act as diet supplements. Sodium was an exception, being present at low concentrations. Therefore, there are no restrictions on the consumption of these plants for people intolerant to those minerals. Moreover, levels of non-essential minerals were not considered toxic. However, mineral contribution of other foods in the daily diet must be considered. Concerning the different years of sampling, it was observed that there is a non-uniform variation on these elements concentrations through time. Considering that such minerals contents are influenced by the environment where they are grown, further studies with the same species cultivated in different regions are recommended. / As plantas são muito utilizadas para fins medicinais, especialmente no Brasil, principalmente devido a sua grande biodiversidade de flora nativa. Embora a determinação dos fitocompostos de vegetais seja o mais recorrente na literatura, vêm aumentando o interesse dos pesquisadores pela composição inorgânica de plantas, visto que os minerais podem apresentar tanto caráter nutricional, quanto tóxico. Deve-se ressaltar também que a presença desses minerais nas plantas está relacionado com o ambiente de cultivo. Sendo assim, o objetivo deste trabalho foi avaliar a composição mineral, em termos de constituintes inorgânicos essenciais e não essenciais para três anos de amostragem, das espécies amazônicas de grande interesse medicinal Cecropia palmata, Cecropia obtusa, Bauhinia variegata L., Bauhinia variegata L. var. alboflava, Mansoa alliacea e Connarus perrottetti var. angustifolius cultivadas em Belém-PA, utilizando a espectrometria de absorção atômica como ferramenta analítica. Todas as espécies apresentaram concentrações de minerais essenciais acima dos valores diários de ingestão recomendados, indicando que podem auxiliar na complementação de dietas alimentares, com exceção para o sódio, que foi encontrado em baixas concentrações. Dessa forma, não há restrições no consumo dessas plantas para pessoas com intolerância a esses minerais. Além disso, não foram encontrados níveis tóxicos de minerais não essenciais nessas plantas, porém, deve-se considerar a contribuição mineral de outros alimentos ingeridos diariamente. Em relação aos diferentes anos de amostragem, foram observadas variações nas concentrações dos elementos, porém tais oscilações não foram uniformes. Tendo em vista que os elementos químicos podem sofrer influências ambientais, ou seja, podem variar dependendo do local de cultivo, estudos complementares com as mesmas espécies em outras regiões são recomendados.
20

Endogenous Risk Perception, Geospatial Characteristics and Temporal Variation in Hurricane Evacuation Behavior

Tahsin, Subrina 13 June 2014 (has links)
The main focus of this thesis was to gain a better understanding about the dynamics of risk perception and its influence on people’s evacuation behavior. Another major focus was to improve our knowledge regarding geo-spatial and temporal variations of risk perception and hurricane evacuation behavior. A longitudinal dataset of more than eight hundred households were collected following two major hurricane events, Ivan and Katrina. The longitudinal survey data was geocoded and a geo-spatial database was integrated to it. The geospatial database was composed of distance, elevation and hazard parameters with respect to the respondent’s household location. A set of Bivariate Probit (BP) model suggests that geospatial variables have had significant influences in explaining hurricane risk perception and evacuation behavior during both hurricanes. The findings also indicated that people made their evacuation decision in coherence with their risk perception. In addition, people updated their hurricane evacuation decision in a subsequent similar event.

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