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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.
431

Humorwork, Feminist Philosophy, and Unstable Politics

Billingsley, Amy 30 April 2019 (has links)
This dissertation examines humor as a situated practice of reappropriation and transformation undertaken by a subject within a social world. I bring together insights from humor studies, philosophy of humor, and feminist philosophy (especially feminist continental philosophy) to introduce the concept of humorwork as an unstable political practice of reappropriating and transforming existing images, speech, and situations. I argue that humorwork is an unstable politics because the practice of reappropriation and transformation often exceeds the intentions of the subject practicing humor, taking on a continued life beyond the humorist’s intentions. By focusing on the practice of humor, the subject who produces it, their social and political world, the affects circulated through political humor, and the politics of popular and scholarly discourse about humor, I push against a reductive, depoliticized concept of humor and the trivializing gesture of “it’s just a joke.” Instead, I argue that humorists are responsible and connected to (if not always blameable) for the social and political life of their humorwork, despite the unstable and unpredictable uptake of humor against a humorist’s intentions.
432

The Contradiction of Representation in Levinas's Command of the Other and the Possibility of Responding through the Dialogicality of the Self

Claflin, Robert 01 May 2019 (has links)
Emmanuel Levinas views the phenomenological tradition as being predicated on an asymmetrical relationship between the self and the other in which the self possesses the power to dominate and represent the other. This leads to the reduction of the other to the same. Instead, he wants to flip this relationship in favor of the other by showing how the very qualities of alterity and infinity enable the other to resist the self’s attempts at representation. Furthermore, he conceives of an ethics in which the self is compelled to listen to the other’s command and respond accordingly. The inherent issue in such an ethics as Levinas’s is that the self is held responsible for responding to a command which it cannot represent in some meaningful way. Thus, either Levinas contradicts himself or there must be some way to respond to the other’s command prior to representation. Levinas himself says that the transcendent relationship itself involves the convergence of the self and the other through language. Language occurs prior to representation and involves the putting in common of both the self and the other’s worlds. It is an ethical donation to the Other. As well, Levinas’s idea of paternity suggests the dialogical nature of the self in the ethical relationship. Using theories of self-consciousness by Hegel, Sartre, and Meade, I show how the dialogical nature of the social self enables it to enter into a transcendent relationship without committing an act of violence.
433

Metodologia para modelagem do sistema agroindustrial visando identificar parâmetros de rastreabilidade e qualidade - aplicação na malacocultura continental. / A methodology for Agri-industrial system modeling in order to identify traceability and quality parameters - a continental malacoculture application.

Cunha, Gilberto José da 07 October 2008 (has links)
O trabalho apresenta como inovação, inclusive em nível internacional, a utilização de métodos e técnicas de engenharia de software e de sistemas aplicadas aos Sistemas Agroindustriais (SAG), definindo uma metodologia objetivando facilitar maior compreensão dos relacionamentos e atividades dos diversos agentes componentes de um SAG; modelar graficamente as atividades dos agentes e demais envolvidos em cada etapa de uma cadeia produtiva, através de IDEF0, BPMN e Casos de Uso; identificar informações para qualidade, rastreabilidade do produto e seus insumos ao longo da cadeia produtiva. Efetua, também com caráter inovador, a aplicação dessa metodologia na área de produtos exóticos através da modelagem de atividades pertencentes ao SAG da Malacocultura Continental (criação comercial de escargots), agronegócio inserido na política de incentivo à Agroindústria Familiar. As exigências dos consumidores de produtos agropecuários em relação a qualidade, segurança e rastreabilidade tem crescido ano após ano devido ao medo de problemas com saúde, como o mal da vaca louca. A modelagem do Sistema Agroindustrial (SAG) possibilita identificar necessidades de informação e automação em uma cadeia produtiva, explorar essas possibilidades de modo a permitir a especificação de sistemas de informação que suportem os negócios dos diversos agentes ao longo da cadeia produtiva satisfazendo os requisitos de qualidade e rastreabilidade dos consumidores. A aplicação de um modelo de caso de uso também é apresentada, descrevendo as atividades componentes de processos ao longo da cadeia produtiva, permitindo a identificação de requisitos e informações de rastreabilidade e qualidade. A técnica de casos de uso aplicada na cadeia produtiva ajuda na especificação de sistemas de informação de melhor qualidade e mais aderentes aos processos de negócio envolvidos. Como exemplo é a apresentada a modelagem (utilizando IDEF0, BPMN e casos de uso) de alguns processos de negócio e informação pertencentes à cadeia produtiva da malacocultura continental. A aqüicultura mundial tem se destacado pelo crescimento e sucessivo aumento de produtividade, conferindo, a este tipo de produção, posição de destaque dentro do setor pecuário internacional. Entre as várias modalidades de aqüicultura, nas duas últimas décadas, a criação de escargots (malacocultura) tem merecido atenção de empresários, órgãos de fomento governamentais e pesquisadores. Em águas continentais, a malacocultura continental especialmente a ampularicultura pode ser reconhecida como forma para produção de moluscos com baixo impacto ambiental, sob sistema de produção compatível com pequenas propriedades, o que contribui na maior oferta de alimento para as famílias rurais, aumento na disponibilidade de alimentos de alto valor nutricional e na renda familiar. / It is proposed the application of some Systems and Software Engeneering techniques to the modeling of agro-industrial systems, in an innovative way, defining a methodology in order to better understand the activities and relationships among the many agents within an specific supply chain. It also permits the productive chain graphical modeling using IDEF0, BPMN and Use Cases. The main goal is to identify information for product traceability and quality through the productive chain. There is also presented, another innovation, the application of this methodology to the Continental Malacoculture Agro-industrial System. Customers\' requirements for agro food products quality, safety and traceability have been rising year after year due to the fear of health problems, such as the mad cow disease. The Productive Chain Modeling helps identifying the information and automation needs of a production chain, exploring its possibilities in order to specify information systems that support the business of the many agents throughout the agro food chain and fulfills customers\' quality and traceability requirements. The application of Use Case Model is also presented for requirements and traceability identification and gathering throughout the productive chain. The Use Case technique applied to the productive chain helps to specify more quality and adherent information systems. As an example of those methods, some business and information processes modeling applied to the Continental Malacoculture Productive Chain are presented, using the IDEF0, BPMN and use case techniques. Worldwide aquaculture has increased in importance due to growth and successive increase in productivity, conferring this type of production an outstanding position in the international animal production sector. Amongst different modalities of aquaculture, in the last two decades, the production of escargots (malacoculture) has deserved attention from businessmen, government and researchers. In continental waters, Continental Malacoculture, especially ampullariculture can be seen as a way of producing low impact mollusks, using a system compatible with small farms production, contributing to a greater increase in the availability of high nutritional value food and also improving rural families\' income.
434

Kinematics and dynamics of continental deformation

Penney, Camilla Emily January 2018 (has links)
In contrast to the oceans, deformation in the continental lithosphere is distributed over broad regions. This dissertation is composed of three separate but related studies investigating the kinematics and dynamics of such deformation. The first two studies look at the Makran subduction zone, and the third focusses on deformation in South East Tibet. The first study is an investigation of the 11 May 2013 M w 6.1 Minab earthquake which occurred at the western end of the Makran subduction zone, adjacent to the transition to continent-continent collision in the Zagros mountains. Seismological, geodetic and field results are used to study the source parameters and slip distribution of this earthquake, and demonstrate that the earthquake was left-lateral and occurred on a fault striking ENE–WSW; approximately perpendicular to previously studied faults in the adjacent Minab-Zendan-Palami fault zone. Geological and geomorphological observations of similar faults in the vicinity are used to infer that vertical-axis rotations allow a series of such faults to accommodate ∼15–19 mm/yr of N–S right-lateral shear. The dynamic implications for the transition between subduction and continental collision are discussed. The second study looks at the Makran region as a whole. First, the shape and depth of the interface with the Arabian plate is constrained by modelling the depths and mechanisms of earthquakes across the region, and combining these with additional seismological constraints. These constraints on the subduction interface are used to investigate elastic strain accumulation on the megathrust in the western Makran, which has important implications for seismic and tsunami hazard in the region. Second, the kinematics at the northern edge of the Makran accretionary prism are investigated using a combination of geodetic and geomorphological observations, addressing the long-standing tectonic problem of how the right-lateral shear taken up by strike-slip faulting in the Sistan Suture Zone in eastern Iran is accommodated at the zone’s southern end. Finally, the kinematics and dynamics of the accretionary prism are investigated. By considering the kinematics of the 2013 Balochistan and Minab earthquakes, local gravitational and far-field compressive forces in the Makran accretionary prism are inferred to be balanced. This force balance allows the mean shear stress and effective coefficient of friction on the Makran megathrust to be calculated, 5–35 MPa and 0.01–0.03 respectively. The final part of this thesis focusses on the temporal evolution of topography in South East Tibet. Recently published paleoaltimetry results based on stable-isotope geochemistry are used to provide constraints on vertical motions. These demonstrate that uplift is much slower than had previously been suggested from thermochronometric data. Numerical modelling of the time evolution of a gravitationally-driven fluid is used to investigate the effect of lateral rheological contrasts on the shape and evolution of topography. In such a flow, material at the surface can be transported hundreds of kilometres, an effect which should be accounted for in paleoaltimetric analysis. Lateral rheological contrasts, analogous to the relatively undeforming Sichuan Basin and Central Lowlands of Myanmar, can reproduce the main features of the present-day topography, GPS velocity field and earthquake-derived strain rate without the need for a low-viscosity lower-crustal channel.
435

Diatomáceas perifíticas de cursos d´agua do Parque Estadual de Ibitipoca (PEI), Minas Gerais , Brasil: composição florística

Canani, Luís Gustavo de Castro January 2012 (has links)
O perifíton é formado por uma complexa comunidade de organismos aderidos a um substrato orgânico ou inorgânico, dos quais as diatomáceas (Bacillariophyta) constituem importante parcela. Mais recentemente inventários florísticos que contemplam as diatomáceas bentônicas em sistemas lóticos vêm incrementando o conhecimento da flora na região Neotropical e Neosubtropical, porém grande parte desses sistemas permanece inexplorado, especialmente em águas oligotróficas, de altitude e de baixo pH. Tais ecossistemas em geral possuem uma flora bastante peculiar, e são importantes referências em termos qualidade de água. Desta forma, o presente estudo teve por objetivos contribuir para o conhecimento da flora de diatomáceas perifíticas do Parque Estadual do Ibitipoca, localizado na serra da Mantiqueira em Minas Gerais. Como resultado, foram identificados 15 gêneros, 18 espécies e duas variedades taxonômicas. Duas novas espécies do gênero Eunotia são propostas e três espécies do gênero Nupela não puderam ser identificadas de acordo com a literatura, sendo provavelmente novas para a ciência. São feitos 16 registros pioneiros para o estado de Minas Gerais, sendo quatro delas primeiras ocorrências em território brasileiro. A composição taxonômica das diatomáceas perifíticas do Parque Estadual do Ibitipoca apresenta semelhanças com a flora de outros ambientes oligo-distróficos já inventariados nos Neotrópicos. Palavras-chave: ambientes continentais, águas oligotróficas, Eunotia, Nupela, taxonomia de criptógamos. / The periphyton is composed by a complex community of organisms adhered to an organic or inorganic substrate, and diatoms (Bacillariophyta) constitute an important part of it. More recent floristic inventories in lotic systems that include benthic diatoms increased the knowledge of the Neosubtropical Neotropical flora for the region, but most environments remains unexplored, especially those with oligotrophic and low pH waters in altitude sites. Such ecosystems in general have a very peculiar flora and are important indicators of water quality. Thus, the present study aimed to contribute to the knowledge of periphytic diatom flora of Ibitipoca State Park, located in the Mantiqueira ridge, in Minas Gerais. As a result, we identified 15 genera, 18 species and two taxonomic varieties. Two new species of Eunotia are proposed and three species of the genus Nupela could not be identified according to the literature, and are probably new to science. Sixteen new records were made for the state of Minas Gerais, including four first occurrences for Brazil. The taxonomic composition of the periphytic diatoms of Ibitipoca State Park share similarities with other oligo-dystrophic environments already surveyed in the Neotropics.
436

Investigating past and present continental earthquakes with high-resolution optical imagery

Zhou, Yu January 2016 (has links)
Over the past few decades, remote sensing has emerged as a powerful tool for studying active faulting in continental regions. However, the commonly used remote sensing techniques, including radar interferometry, visual inspection of imagery, and image matching, cannot measure three-dimensional (3D) surface displacements in earthquakes, limiting our ability to investigate faulting. The improvement of very high-resolution (VHR) optical imaging systems (stereo in particular) in recent years has made it possible for earth scientists to measure 3D surface deformation remotely. In this thesis, I contribute to assessing the capability of VHR optical imagery, by determining earthquake deformation from four different types of earthquakes (different in sense of slip and date of the event). In the case of the 2010 M<sub>w</sub> 7.2 El Mayor-Cucapah, Mexico earthquake, I show that digital elevation models (DEMs) derived from Pleiades stereo imagery are comparable to light detection and ranging (LiDAR) surveys, and differencing pre- and post-earthquake DEMs can measure 3D displacements, which will be very useful for studying future earthquakes. For the 2013 M<sub>w</sub> 7.7 Balochistan, Pakistan earthquake, I determine the vertical motion from a post-earthquake Pleiades DEM and find constant fault kinematics throughout the Late Quaternary. This study has resolved a current controversy of the Balochistan earthquake, in which it has been argued that kinematics of the Hoshab fault switches between strike-slip and dip-slip. Applying historical aerial, KH-9 Hexagon spy satellite, SPOT-2 and modern SPOT-6 images to the 1978 M<sub>w</sub> 7.3 Tabas-e-Golshan earthquake, I measure the coseismic and postseismic displacements, and show that the Tabas fold system in eastern Iran may exhibit characteristic slip behaviour. Combining Pleiades imagery, fieldwork and geological dating techniques, I determine slip in the 1556 Huaxian earthquake in China and the recurrence interval for similar events. These examples demonstrate the usefulness of high-resolution optical imagery in investigating past and present earthquakes.
437

Inflammatory bowel disease in the Chinese population. / CUHK electronic theses & dissertations collection

January 2004 (has links)
Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) that result in considerable morbidity and impaired quality of life. Although IBD is ubiquitous, heterogeneity in incidence is noted geographically and among different ethnicities, presumably due to genetic and environmental factors. The incidence and prevalence of IBD has plateaued in many Western countries but are increasing in developing nations. There is a lack of data on IBD pertaining to the Chinese population. / Studies were conducted to determine the characteristics of IBD in the Chinese population. The incidence of IBD in the Chinese population is a fifth to a tenth of Western societies but has risen sharply over the past decade. Several distinct demographic and phenotypic features were noted in the Chinese IBD population. Genetically, Chinese CD patients do not harbour the NOD2/CARD15 polymorphisms unlike Caucasian CD subjects. ANCA and ASCA are serologic markers that are highly specific for UC and CD respectively in the Chinese but ANCA sensitivity in Chinese UC is significantly lower than in Caucasian UC, while quantitative IgG ASCA (and not IgA) is a moderately sensitive test for CD. These markers are useful in differentiating UC from CD. A Chinese translation of the Inflammatory Bowel Disease Questionnaire (IBDQ) was developed and validated to be reliable, sensitive to change and reproducible. A prospective cross-sectional survey of the disease-related knowledge of Chinese and Australian IBD patients identified a low level of IBD-knowledge but with a similar quality of life as Caucasians with IBD. There was a similar but high rate of use of complementary alternative medicines in both populations. / These studies were instrumental in: describing IBD in the Chinese population; developing a Chinese IBD database; acquiring techniques of investigating genetic polymorphisms and ASCA serology; devising the Chinese IBDQ to open up IBD trials to Hong Kong; and identifying knowledge deficiencies to help plan a targeted education programme. / Leong Rupert Wing-Loong. / Adviser: Joseph J.Y. Sung. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (M.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
438

Study of inherited disorders of mitochondrial fatty acid oxidation in Chinese. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Conclusions. Our results showed that conventional in vitro FAO rate assay and acylcamitine profiling in cultured skin fibroblasts could be simplified and performed simultaneously by using the new combined method. Using the new derived parameter, TC, the new method can also reliably detect CUD. Together with molecular studies of ETFA, ETFB and ETFDH genes, the method could detect and confirm a diagnosis of MADD. No definitive case of FAOD was found in a cohort of sixteen SUD cases by the combined method. The new combined method has the potential to be applied as second-line laboratory test for detecting FAOD. (Abstract shortened by UMI.) / First-line laboratory investigation of patients with FAOD is based on some specialized biochemical tests in body fluids including blood/urine carnitine and acylcarnitines, urine organic acids and acylglycines. Further confirmatory tests involve functional assessments of the FAO pathway in cultured skin fibroblasts. The two conventional methods are tritium water release assay for determination of total FAO rate and acylcarnitine profiling for detection of individual FAOD. Based on the basic principles of these two methods, I hypothesized that the total FAO rate assay could be combined with the acylcarnitine profiling if an appropriate substrate and measurement technique were used. In this thesis, I described the development and validation of such assay. In view that the conventional methods cannot reliably detect CUD and MADD, I attempted to test a new derived parameter namely total even-chain acylcarnitines (TC) using the proposed new combined assay for detection of CUD. As mutation analysis of MADD in Chinese patients has not been carried out, a genomic approach was developed to confirm the diagnosis of MADD detected by the new combined assay. Also, the new assay was applied to detect FAOD in a cohort of sudden unexpected death (SUD) Chinese infants. / Mitochondrial fatty acid beta-oxidation (FAO) is a vital process for energy production in most tissues, particularly the skeletal muscle and heart. It also plays an important role to maintain sufficient energy supply through hepatic ketone body formation during fasting and stress. Most fatty acid oxidation disorders (FAOD) may lead to hypoketotic hypoglycaemia, hepatic dysfunction, encephalopathy, skeletal myopathy and cardiomyopathy. / Molecular studies of genomic DNA from five MADD patients in three unrelated Chinese families were performed. Four novel mutations in ETFDH gene were found in two families: one deletion (c.1355delG) and three missense (c.250G>A, c.409C>T and c.1400G>C) mutations. In another family, only one splice site (IVS2+1G>A) mutation in ETFA gene was identified. / The definitive diagnosis in nine CUD patients were made by a very low rates of carnitine uptake (&lt;5% of control) as determined by the conventional radioactive carnitine uptake assay in cultured skin fibroblasts. When using the new combined FAO rate and acylcamitine profiling method, the calculated TC levels of these patients were all below 9.3 nmol/mg protein/96h and were well separated from the control group. At this cutoff value, ROC analysis gave a sensitivity of 100% and specificity of 87.5%, the AUC was 0.993, (p&lt;0.001). Therefore, both conventional radioactive carnitine uptake assay and our new combined assay could be useful for the diagnosis of CUD. / Law, Lap Kay. / Advisers: Christopher Lam Wai Kei; Nelson Tang Leung Sang. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3420. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 177-202). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
439

Aplicação de um modelo paramétrico para a estimativa do transporte de sedimentos arenosos na Bacia de Campos

Rodrigues Martins, Ricardo January 2006 (has links)
Made available in DSpace on 2014-06-12T17:40:20Z (GMT). No. of bitstreams: 2 arquivo6178_1.pdf: 5817477 bytes, checksum: 04bd5e297fab3c3cf0e03323d464044c (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / Estudos sobre os processos de transporte de sedimentos que ocorrem na Bacia de Campos têm grande importância, uma vez que podem contribuir, por exemplo, para o melhor entendimento dos eventos de formação depósitos sedimentares, que são potenciais reservatórios de óleo, ou ainda fornecer elementos que auxiliem na compreensão de alterações nas formas de fundo do leito marinho em áreas onde há dutos submarinos instalados. O presente trabalho consistiu na avaliação do transporte de sedimentos total (de fundo e por suspensão) na camada limite de fundo em quatro pontos distintos da Plataforma Continental, na região próxima ao Cabo de São Tomé (22ºS), localizados em diferentes lâminas d água. Utilizou-se um modelo paramétrico 1-D que foi adaptado para calcular o transporte a partir de séries históricas simultâneas de correntes e ondas observadas. Também foram considerados dados locais da granulometria dos sedimentos, das formas de fundo e das propriedades termo-halinas da água do mar. O resultados alcançados mostraram que a direção da corrente é determinante na direção do transporte de sedimentos. A direção predominante do transporte resultante foi coerente com os alinhamentos das formas de fundo encontradas em áreas próximas. Observou-se ainda que a influência do clima de ondas, disponibilizando sedimentos para serem transportados por suspensão, diminui com o aumento da profundidade. Concluiu-se, portanto, que o modelo foi capaz de fornecer respostas coerentes com base nos modos de transporte esperados para esta região
440

Comunidades de Polychaeta (Annelida) da plataforma continental ao largo de Santos, SP: Composição, distribuição e estrutura trófica / Polychaetes Communities from continental shelf offshore of Santos, Brazil: composition, distribution and trophic structure

Mauricio Shimabukuro 07 April 2011 (has links)
A composição e distribuição de poliquetas foram estudadas na região da plataforma continental sudeste brasileira adjacente à Baixada Santista (Projeto temático ECOSAN), sendo realizadas coletas em 21 estações, durante dois períodos, por meio de um \'box-corer\' (0.09m2). Poliqueta foi o grupo dominante da macrofauna, totalizando 16.274 indivíduos e 214 espécies. A distribuição da fauna relacionou-se com as características do sedimento, como o tamanho médio do grão e seu grau de seleção, ao longo de um gradiente batimétrico, verificando-se a existência de três comunidades distintas: comunidade costeira, situada ao longo da costa em locais de areia muito fina e fina bem selecionadas, dominada por Apoprionospio dayi; comunidade de transição, situada em sedimentosmistos e heterogêneos, entre 50-84m e caracacterizada por Aphelochaeta sp., Levinsenia gracilis e Aricidea (A.) catherinae; comunidade de plataforma externa, situada em sedimentos lamosos profundos, caracterizada por Sigambra grubii, Sternaspis capillata e Leitoscoloplos kerguelensis. Fatores oceanográficos, como hidrodinamismo e intrusão sazonal da ACAS, foram considerados como secundários na estruturação das comunidades. De modo geral, a riqueza e diversidade de poliqueta foram altos, variando de 20 a 66, e de 2,37 a 5,45 respectivamente. A região entre 50-84m apresentou picos desses descritores, provavelmente associados ao sedimento de maior heterogeneidade e à sobreposição de comunidades. Os grupos funcionais apresentaram distribuição semelhante a da composição de espécies. Os consumidores de interface foram dominantes na região costeira, enquanto depositívoros de superfície, e sub-superfície móveis de probóscide lisa, e carnívoros móveis mandibulados, foram dominantes na região entre 50 e 100m. / Composition and distribution of polychaetes were studied in southeastern Brazilian continental shelf adjacent to Santos (ECOSAN Thematic Project). Aiming a spatio-temporal community comprehension, 21 stations were sampled in duplicates during August/2005 and February/2006, with a box-corer (0.09 m2). Polychaete was the dominant macrofauna group, totalizing 16274 individuals and 214 species. The fauna distribution along the depth gradient was related to sediment type, mean grain size and sediment sorting, which partially promoted the existence of three distinct communities: (1) a shallow community, dominated by Apoprionospio dayi, inhabiting very fine and fine well selected sand; (2) a community dominated by Aphelochaeta sp., Levinsenia gracilis and Aricidea (A.) catherinae, inhabiting mixed sediments between 50-84 m depth; (3) and a community dominated by Sigambra grubii, Sternaspis capillata and Leitoscoloplos kerguelensis, inhabiting muddy sediments in a deeper region of the continental shelf. The local hydrodynamic regime and the deep intrusion of the South Atlantic Central Water (SACW) were considered secondary factors in the distribution of polychaetes. High values of richness and diversity were observed throughout the shelf, ranging from 20 to 66, and from 2.37 to 5.45 respectively. The region between 50-84m showed peaks of these community descriptors, probably associated with greater sediment heterogeneity, and the communities overlapping. The functional groups showed a similar distribution to species distribution. Interface-feeders were dominant functional group in coastal region, while motile surface and subsurface deposit feeders with soft proboscis and motile carnivores with jaws were dominant in the region between 50 and 100m.

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