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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.
361

Dinamica da dispersão de sementes e regeneração de plantas da planicie litoranea da Ilha do Mel, PR

Marques, Marcia Cristina Mendes 15 March 2002 (has links)
Orientador: Paulo Eugenio A. M. de Oliveira / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-31T19:03:43Z (GMT). No. of bitstreams: 1 Marques_MarciaCristinaMendes_D.pdf: 5785678 bytes, checksum: 3b9988a81542b90132277956c9fb3ce5 (MD5) Previous issue date: 2002 / Resumo: A Ilha do Mel está localizada em Paranaguá, região central do litoral do Estado do Paraná (25°29'/25°34'32"S e 48°17'15"/48°23'16"W) e compreende uma área aproximada de 2760ha, na qual estende-se uma planície litorânea costeira. Sobre esta desenvolve-se uma vegetação bastante heterogênea, onde são reconhecidos três principais tipos vegetacionais: Vegetação de Praia (P), Restinga Arbustiva (R) e Floresta de Restinga (F). Neste gradiente foi desenvolvido um trabalho abordando, de forma comparativa, os processos de dispersão e regeneração das plantas dos três tipos vegetacionais e de dois tipos de Floresta de Restinga: a Floresta não inundável (FNI) e a Floresta inundável (FI). Com base nas características morfológicas de frutos, sementes e plântulas de 238 espécies, foram descritos os modos de dispersão e tipos morfofuncionais de plântulas e avaliadas as variações em suas freqüências no gradiente P a F. Do total de espécies analisadas, zoocoria foi o modo de dispersão mais freqüente (56% das espécies), seguido por anemocoria (26%) e autocoria (18%). As distribuições dos modos de dispersão foram influenciadas pelo ambiente, havendo um predomínio dos processos abióticos (anemocoria e autocoria) nos locais abertos e sujeitos a estresse (P e R), e biótico (zoocoria) nos tipos vegetacionais mais fechados e complexos (F). Acompanhando esta variação, espécies da P e R apresentaram sementes, em média, menores que em F, o que sugere que o ambiente deva restringir a ocorrência de espécies em função da forma do fruto e da semente. Plântulas do tipo fanerocotiledonar-epigeal-foliáceo ocorreram na maior parte das espécies (57%), seguido por criptocotiledonar-hipogeal-de reserva (39%), criptocotiledonar-epigeal-de reserva, fanerocotiledonar-epigeal-de reserva e fanerocotiledonar-hipogeal-de reserva Ountos 4%). Espécies de cotilédones foliáceos e armazenadores distribuíram-se nas mesmas proporções na P, R e F, indicando que morfologia da plântula não está necessariamente associada a mudanças microambientais. No estudo fenológico da FNI e FI, plantas do dossel e do sub-bosque (total 55 espécies) foram acompanhadas por dois anos na Ilha do Mel, região com pouca diferença climática entre o período superúmido (Setembro a Maio) e úmido (Junho a Agosto). As duas florestas apresentaram padrões semelhantes, com pico de queda de folhas, brotação, floração e frutificação ocorrendo sucessivamente ao longo da estação superúmida. Quase todas fenofases mostraram correlações mais fortes com o comprimento do dia e a temperatura média. Plantas do dossel foram mais previsíveis com relação à ocorrência das fenofases que as do sub-bosque. Para avaliar se florestas localizadas em local de clima pouco sazonal podem apresentar ritmos, a chuva de sementes e a emergência de plântulas foram estudadas, ao longo de dois anos, na FNI e na FI. As duas florestas apresentaram os mesmos padrões de dispersão e germinação das sementes, apesar das diferenças existentes na umidade do solo e na disponibilidade de luz no subosque. A chuva de sementes foi sazonal e bimodal, com um pico maior no final da estação mais úmida (AbrilMaio) e outro menor na estação menos úmida (Agosto), refletindo os padrões fenológicos das espécies zoocóricas e anemocóricas, respectivamente. Com exceção do modo de dispersão, nenhum dos demais atributos das espécies (forma de vida, tamanho da semente, tipo morfológico de plântula) parece definir os ritmos das florestas. A emergência das plântulas foi unimodal, com pico no meio do período mais úmido (Janeiro), embora as demais épocas do ano não tenham limitado completamente a germinação. Mesmo havendo umidade durante todo o ano, 57% das espécies apresentaram pelo menos 4 meses de atraso na emergência das plântulas. Ritmo da chuva de sementes e dormência determinaram o ritmo da emergência das plântulas que é concentrada na época mais úmida, quando a disponibilidade de nutrientes no solo é maior e quando todas as demais atividades fenológicas das florestas ocorrem. Para avaliar a dinâmica da regeneração existente entre as Florestas de Restina, os compartimentos formados pelas comunidades de sementes, plântulas e jovens dos dois tipos florestais (FNI e FI) foram avaliados. A incorporação de indivíduos em ambas dependeu, principalmente, da entrada de propágulos (via chuva de sementes) de espécies autóctones (FNI=75%, FI=84% das espécies). Nas duas florestas houve dramática redução na densidade de indivíduos (>98%) na passagem das plantas do estádio de semente a adulto, acompanhada por diminuição na similaridade entre compartimentos (índice de similaridade de S0rensen variando de ca. 80% para ca. 58%) e aumento da diversidade (índice de diversidade de Shannon variando na FNI de 0,39 a 1,19 e na FI de 0,91 a 1,31). Isto deveu-se basicamente à redução mais drástica nas densidades das espécies comuns e manutenção das raras entre os compartimentos. Plantas de diferentes estádios, em geral, não se relacionaram em termos de densidade e distribuição espacial (na maioria dos casos correlações não significativas) sugerindo a independência das fases no processo de regeneração. As semelhanças entre as florestas em relação à densidade média e ao índice de diversidade de Shannon são mantidas até o estádio de jovem, quando a FNI torna-se mais densa e menos diversa que a FI e a similaridade florística entre elas diminui. Isto é explicado pelas diferenças apresentadas pelas espécies quanto à limitação à dispersão, à emergência e ao estabelecimento, conduzindo a processos distintos de recrutamento nas duas florestas. Os resultados mostraram que: 1) diferenças ambientais e na freqüência de formas de vida existentes no gradiente da planície litorânea refletem nos padrões de distribuição de atributos reprodutivos das espécies, o que deve estabelecer diferenças nos modelos de regeneração em cada local; 2) sazonalidade fenológica e nos ritmos de dispersão de sementes e emergência de plântulas nem sempre estão associados à alta sazonalidade climática e no caso destas Florestas de Restinga o deslocamento destes eventos para a época superúmida, parece se ajustar às condições necessárias para a eficiente ciclagem dos nutrientes; 3) Florestas de Restinga são sistemas com modelos de regeneração relacionados, porém particularmente direcionados, em função das diferenças que as espécies vegetais apresentam em relação ao sucesso no estabelecimento dos indivíduos / Abstract: (Seed dispersal and plant regeneration dynamics in a Sandy Coastal Plain on Ilha do Mel, southern Brazil): The island Ilha do Mel is located in the municipality of Paranaguá (25°29'/25°34'32"S e 48°17'15"/48°23'16"W) in the central coastal region of Paraná State, Brazil and comprises 2760ha. The higher areas above the Sandy Coastal Plain contains very heterogeneous vegetation in which it is possible to recognize three major vegetation types: beach/dune vegetation (P), scrub or "restinga" (R), and sandy coastal forest (F). Here, dispersal and regeneration mechanisms were studied along this P to F gradient and in two types of sandy coastal forests: Unflooded (FNI) and Flooded (FI). The morphologies of fruit, seeds, and seedlings of 238 plant species were analyzed, and the frequency of dispersal and seedling syndromes were compared in the P to F gradient. Zoochory was the most frequent dispersal syndrome (56% of total species), followed by anemochory (26%) and autochory (18%). Distribution of dispersal syndromes was associated with vegetation type. Abiotic processes (anemochory and autochory) were more important in open and stressed sites (P and R) while biotic processes (zoochory) were important in closed and more complex sites (F). Dispersal syndromes in vegetation types were related to seed sizes, i.e. seed size in P and R species were smaller than F species. This suggests that environmental features limit species occurrence due to fruit and seed shapes. Seedling types were phenerocotylar-epigeal-foliaceous (57%), cryptocotylar-hipogeal-reserve (39%), and the last 4% were either cryptocotylar-epigeal-reserve, phanerocotylar-epigealreserve or phanerocotylar-hipogeal-reserve. Photosynthetic and reserve cotyledonous seedlings were equally distributed along P, R and F, suggesting that seedling morphology is not related to environmental factors. The phenology of 55 canopy and understory plant species in the FNI and FI were studied over two years. In these sites, climate (mainly rainfall) in the wetter season (September to May) is similar to that of the less wet season (June to August). FI and FNI showed very similar phenological patterns in which leaf fali, flushing, flowering, and fruiting occurred during the wetter season. Most phenological phases were correlated with daylength and average temperature. Phenology of canopy specles was more predictable than that of understory species. To test whether putatively aseasonal forests show rhythms, the seed rain and seedling emergence in the FNI and FI was studied for two years on Ilha do Mel island. Despite soil moisture and light differences between the two forests, FNI and FI had similar dispersal and germination patterns. Seed rain was seasonal and bimodal. The first peak occurred at the end of the wetter season (April to May) and the second one in the less wet season (August). These peaks reflect, respectively, the peaks of zoochorous and anemochorous species. Other plant characteristics (life form, seed size and seedling morphology) apparently do not show clear patterns. Seedling emergence was seasonal and unimodal but also occurred along the entire year. Even in this apparently aseasonal forest approximately 57% of species had seedling emergence four or more months after dispersal. Therefore both seed dormancy and the timing of seed dispersal drive the rhythm of seedling emergence in these forests. The peak in germination occurs in the wetter season (January) when soil fertility is higher and other phenological events also occur. Dynamics of FNI and FI were studied on Ilha do Mel Island, specifically comparing community composition of seeds, seedlings and saplings in each forest. New individual plants are incorporated in forests mainly from seed rain of autochthonous species (FNI =75% and FI =84% of species). During the growth of the plants (from seed to adult stages) in both of these forests, declines in plant density (>98%) and floristic similarity (Sorensen's Similarity Index from -80% to -58%) occur, associated with an increase in diversity (Shannon's diversity index from 0,39 to 1,19 in the FNI, and 0,91 to 1,31 in the FI). This was due to a strong reduction in density of the common species. Plants are uncoupled in their density and spatial distribution (uncorrelated) among stages, suggesting independence of the stages during the regeneration processo Through the sapling stages, the FNI and FI forests are very similar (density and Shannon's diversity index), after which the FNI was more densely populated and less diverse than the FI, with consequent reduction in their floristic similarity. Dispersal limitation, emergence limitation, and establishment limitation are very different in the FNI and FI, which probably is associated with particular recruitment patterns. It is suggested that: 1) 80th environmental and life form differences along the Sandy Coastal Plain gradient reflect differences in plant reproductive, and plant growth, patterns. 2) Phenological, seed dispersal and seedling emergence rhythms are not only or always related to large climatic seasonality. In these sandy coastal forests the occurrence of phenological patterns associated with the wetter season fits the hypothesis of efficient nutrient cycling in plant communities in relatively infertile soils. 3) Sandy Coastal Forests are systems with a connected but singular regeneration pattern due to differences in establishment success of plant species. Probably the relationship between these forests and other vegetation types is due to a successional patterns along the Coastal Plain / Doutorado / Biologia Vegetal / Doutor em Ciências Biológicas
362

Diversidade e potencial forense de dípteros necrófagos (Faniidae, Muscidae e Sarcophagidae) em ambientes litorâneos de Pernambuco sob diferentes graus de antropização

BARBOSA, Taciano de Moura 25 February 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-12T12:22:13Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Barbosa, 2015 (Biblioteca).pdf: 1702941 bytes, checksum: 656dcfc0d79bf790cef3055ca31e3579 (MD5) / Made available in DSpace on 2016-04-12T12:22:13Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Barbosa, 2015 (Biblioteca).pdf: 1702941 bytes, checksum: 656dcfc0d79bf790cef3055ca31e3579 (MD5) Previous issue date: 2015-02-25 / FACEPE / Estudos sobre dípteros necrófagos no Brasil têm revelado uma elevada riqueza de espécies associadas à decomposição de carcaças e cadáveres. Entretanto, apesar da extensão região litorânea do Brasil, inventários faunísticos nesses ambientes são negligenciados, bem como a avaliação do potencial de moscas necrófagas como indicadoras de local de morte – uma importante faceta da Entomologia. Este estudo objetivou analisar a diversidade e o potencial forense dos dípteros das famílias Fanniidae, Muscidae e Sarcophagidae em ambientes litorâneos do estado de Pernambuco sob diferentes graus de influência antrópica. As coletas foram realizadas entre julho de 2012 a agosto de 2013 em seis praias, sendo duas expostas a cada nível de impacto humano. As praias selecionadas foram: Pau Amarelo, Piedade (alta antropização), Itamaracá, Serrambi (média antropização), Carne de Vaca e Tamandaré (baixa antropização). Armadilhas suspensas iscadas com 150 g de fígado de frango ou sardinha foram mantidas em campo por 48 horas em cada expedição de coleta. Foram capturados 6.521 adultos pertencentes a 41 espécies. Sarcophagidae foi a família mais abundante com 53,5% dos indivíduos, seguida por Muscidae (36,0%) e Fanniidae 13,6%. Atherigona orientalis, Peckia (Peckia) chrysostoma e Fannia pusio foram as espécies mais abundantes de cada família no litoral de Pernambuco. Houve ainda o registro de espécies com potencial forense e sanitário, por causar danos à saúde de animais e de humanos ou auxiliar em questões legais, por exemplo, Musca domestica, Synthesiomyia nudiseta, Sarcodexia lambens e Fannia canicularis. Destaca-se a alta riqueza de sarcofagídeos, com 26 espécies, das quais cinco constituem novos registros para o Nordeste, além do primeiro registro de Peckia (Peckia) villegasi para o Brasil. Em relação ao nível de antropização, praias com menores níveis de ação antrópica concentraram 42,6% dos espécimes. Observou-se um alto número de espécies consideradas sinantrópicas, por exemplo, M. domestica, P. chrysostoma, Ophyra chalcogaster, O. aenescens e F. pusio. As contribuições do estudo fortalecem o conhecimento sobre a riqueza e distribuição de dípteros necrófagos na Região Neotropical e fornecem perspectivas para utilização desse grupo como bioindicadoras da qualidade ambiental. / Studies on necrophagous dipterans in Brazil have revealed a high richness of species associated with decomposing carcasses and cadavers. However, despite the extension of the coastal region in Brazil, faunistic surveys in those environments are neglected, as well as the assessment of the potential of necrophagous flies as indicators of site of death – an important aspect of Forensic Entomology. This study aimed at analyzing the diversity and the forensic potential of dipterans from the families Fanniidae, Muscidae and Sarcophagidae in coastal environments in the State of Pernambuco under different degrees of anthropogenic influence. Samplings were performed between July 2012 and August 2013 in six beaches, two of each exposed to a different human impact. The beaches selected were Pau Amarelo, Piedade (high impact), Itamaracá, Serrambi (intermediate impact), Carne de Vaca and Tamandaré (low impact). Suspended traps baited with 150 g of chicken liver and or sardine were kept in the field for 48 h in each sampling expedition. 6,521 adults from 41 species were collected. Sarcophagidae was the most abundant Family with 53.5% specimens, followed by Muscidae (36.0%) and Fanniidae 13.6%. Atherigona orientalis, Peckia (Peckia) chrysostoma and Fannia pusio were the most abundant species of each family in the littoral of Pernambuco. Also, species of forensic and sanitary relevance were registered, as they cause damage to the health of humans and other animals or for their use in legal procedures, such as Musca domestica, Synthesiomyia nudiseta, Sarcodexia lambens and Fannia canicularis. Of particular importance is the high richness of flesh flies, with 26 species, of which five are new registers for the Northeastern Region and Peckia (Peckia) villegasi is first reported in Brazil. Regarding the level of anthropogenic influence, beaches with lower impact comprised 42.6% of all individuals. A high number of synanthropic species was related, as it is the case of M. domestica, P. chrysostoma, Ophyra chalcogaster, O. aenescens and F. pusio. The contribution from this study strengthens the knowledge on the richness and distribution of necrophagous dipterans in the Neotropical Region and offers some perspective on the use of those insects as bioindicators of environmental quality.
363

Facilitating Experience through Fabrication and Blue Biophilic Design

Scanlon, Teague 01 January 2019 (has links)
The way humans currently interact with the atmosphere and oceans around us is unsustainable, with pollution entering our waters faster than we are collecting it, and the sea level rising faster than we are building coastal barriers to protect our current infrastructure. This thesis explores the common methodology for communicating climate change and its future effects, and highlights an opportunity for using infrastructure to facilitate interaction with the urban-aquatic interface. By promoting experiential contact with the natural spaces that are most at risk to climate change’s impacts, a sense of stewardship for those spaces will spur behavioral change and activism. On a local level, this thesis explores the history of public access to San Onofre State Beach, and the possibility for the restriction of that access in 2021. Using a 3D topographic and bathymetric model of San Onofre State Beach, I attempt to highlight the beauty of the undeveloped California coastline, and the benefits of keeping this 6.5-mile coastline within the State Parks system.
364

Source determination and predictive model development for Escherichia coli concentrations at F.W. Kent Park Lake, Oxford, Iowa

Simmer, Reid A. 01 July 2016 (has links)
Fecal contamination of Iowa recreational water bodies poses a threat to water quality as well as human health. Concern regarding the health effects of waterborne pathogens resulted in 149 beach advisories across 39 state-owned beaches during the 2015 beach season alone. While the presence of pollution is often clear, its cause and source may be difficult to identify. Furthermore, the current practice in Iowa of sampling once per week leads to high uncertainty and inadequately protects swimmers from exposure. The objective of this study was to determine the influential environmental factors and sources causing spikes in fecal contamination at F.W. Kent Park Lake in Oxford, IA, and to develop a predictive model of beach E. coli concentrations. Water samples were collected at the swimming beach as well as throughout the watershed from May to October, 2015. All samples were analyzed for Escherichia Coli using the IDEXX Colilert enumeration method. Together with weekly data from 2012 through 2014, two predictive models of E. coli based upon influential environmental and water quality variables were developed using EPA Virtual Beach software. These models proved to be more accurate than the current method used to assess risks to swimmers that assumes bacterial concentrations remain constant between samples. In addition, through statistical analysis and modeling, this study found evidence that the main source of fecal contamination were wild geese that frequent the beach.
365

Tropical peat type shoreline protection by detached breakwater and vegetation in Bengkalis Island of Indonesia / インドネシア国ブンカリス島における離岸堤と植生を用いた熱帯性海岸防護に関する研究

Noerdin, Basir 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22415号 / 工博第4676号 / 新制||工||1730(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 平石 哲也, 准教授 馬場 康之, 教授 森 信人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
366

Resilient Architecture: Adaptive Community Living in Coastal Locations

Shannon, Erica 09 July 2018 (has links)
How can architects design for coastal inundation caused by climate change, what are the methods and strategies currently being implemented as a response to coastal inundation, and how can these strategies influence the design approach for a self-sustaining community that can survive and thrive in a low-lying coastal area? Climate change is caused by an expenditure of planet-harming resources being improperly or inefficiently utilized and consumed. This can lead to a rise of global sea level and an increased severity of storm surges. Resilience is defined as the ability to overcome challenges and difficulties. Coastal resilience is the ability for a coastal community to independently withstand shocks caused by hazardous storms and coastal flooding, adapt to future occurrences, and rebuild when necessary. Incorporating resilient and adaptable design elements into architecture could help to create a more sustainable built environment that reacts more efficiently to challenges and difficulties that occur in the natural world. The intent of this thesis is to design a coastal community-living development that serves as a case study for how communities in low-lying areas can be elevated in order to sustain fluctuating coastal conditions. An ideal setting for the implementation of this thesis is Pleasure Beach Park, a low-lying barrier beach located on the coastline of Bridgeport, Connecticut. Through research and analysis of this location, this design responds to and includes essential programmatic elements deemed necessary for a community to exist in the area, as well as vital attributes that collectively form a resilient coastal community.
367

高潮・3次元海浜流および漂砂の解析モデルの構築と実用化に関する研究

田中, 和広 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23149号 / 工博第4793号 / 新制||工||1750(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 平石 哲也, 准教授 馬場 康之, 教授 森 信人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
368

'...and one of time.': A Composition for Full Orchestra with Narration

Rinker, John Thomas 12 1900 (has links)
‘...and one of time.' is a reinterpretation of a small musical moment from Philip Glass' opera, Einstein on the Beach, centered around the phrase "Berne, Switzerland 1905." This reinterpretation is realized through the use of several different compositional techniques including spectral composition, micropolyphony and dodecaphony, as well as the application of extra-musical models developed by Alan Lightman, John Gardner, Italo Calvino and Albert Einstein.
369

The impacts of nest microenvironment on sea turtle hatchling performance and their responses to thermal stress

Unknown Date (has links)
As climate change threatens with sea-level rise and more storms, increased erosion could increase the need for beach nourishment. Alterations to sand characteristics may result in changes to the sea turtle nest microenvironment, impacting the temperature and oxygen levels which may affect hatchling performance. In this study, leatherback, loggerhead, and green nests were sampled from two sites with different sand characteristics in Juno Beach, Florida, USA. Gas exchange was higher in green turtle nests with a greater mixture of sediment. Darker sediment elevated nest temperatures. Finer sediment and a greater mixture of sediment in leatherback nests elevated the nest temperatures; conversely finer sediment, and a greater mixture of sediment decreased loggerhead and green nest temperatures. Elevated nest temperatures reduced leatherback, loggerhead, and green turtle hatchling performance. Understanding the relationships between beach composition, nest environment, and hatchling performance will aid management decisions essential to sea turtle conservation. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
370

Contributions to the study on helminth fauna of Dillon Beach

Gale, Francis C. 01 January 1947 (has links)
Studies on trematodes of marine organisms of the Pacific Coast have been of a scattered and fragmentary nature. J. Stafford (1904) collected and described a number of trematodes from fishes of the north Pacific, but, in his historical survey, Manter (1926) fails to mention specifically any studies covering the waters south of Canada. More recently, in the United States, several contributions to the field have been made by Dr. John E. Guberlet at the University of Washington and at the College of the Pacific by Dr. Alden Noble, under whose guidance this study was made. James Park (1937) revised the genus Podocotyle and added eight new species .from Dillon Beach, California. Descriptions of individual trematodes have been made by various other investigators. The investigation covered by this paper was begun during the summer or 1946 at the Pacific Marine Station.

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