{"id":8006,"date":"2022-02-10T14:27:22","date_gmt":"2022-02-10T16:27:22","guid":{"rendered":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/?page_id=8006"},"modified":"2022-02-10T14:31:56","modified_gmt":"2022-02-10T16:31:56","slug":"gisele-carolina-marquardt-dr","status":"publish","type":"page","link":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/dissertacoesteses\/gisele-carolina-marquardt-dr\/","title":{"rendered":"Gisele Carolina Marquardt DR"},"content":{"rendered":"

\"faixapos6\"<\/a><\/p>\n

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Gisele Carolina Marquardt<\/h2>\n
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Compara\u00e7\u00e3o da biodiversidade e distribui\u00e7\u00e3o das diatom\u00e1ceas planct\u00f4nicas e de sedimentos superficiais em seis reservat\u00f3rios do sul do Estado de S\u00e3o Paulo<\/h3>\n
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ABSTRACT<\/strong><\/p>\n

Diatoms (Bacillariophyceae) are cosmopolitan, unicellular, microscopic algae that occur in different ecosystems. Their main morphological feature is the silica built cell wall possessing a rich sculpted surface that constitutes the frustule. Diatoms are sensitive to a variety of environmental features necessary for its optimal growth that makes them excellent indicators of aquatic ecosystems changes and especially the eutrophication. Despite this, knowledge about diatoms of tropical regions is still considered very insufficient. Present research is part of the AcquaSed project (2010-2014) and focuses, therefore, on tropical systems and their diatom communities. For this purpose, six reservoirs located in the Alto Paranapanema (3 sampling stations) and Ribeira do Iguape\/Litoral Sul (17 sampling units) basins locates in the south of the State of S\u00e3o Paulo were sampled. Water (summer and winter) and surface sediments (winter) samples were collected for the analyses of the reservoirs environmental characteristics and their respective diatom communities. Despite the established paradigm that microorganisms are ubiquitous dispersed, recent taxonomic studies confirmed a distinctive endemic component in the freshwater diatom flora of several localities round the world, and in Brazil a growing number of taxonomic works containing new species description has been published. In the present thesis, some species that occur in the study area and were included in the AcquaSed database are presented as new based on light (LM) and scanning electron microscopy (SEM) analyses, and also as supported by ecological information, type material analysis, and comparison among populations of different habitats and ecosystems. Analyses of samples collected from Brazilian reservoirs revealed a very diverse diatom flora, with unknown and unique diatom species enlightening the importance of tropical diatoms identity and distribution evaluation. Diatom community composition reflects an entire complex of ecological characteristics of a particular location. In this sense, taxonomical studies and floristic surveys are of utmost importance for applied research projects, such as water quality monitoring as well as of a wide range of basic research such as taxonomic monographs and reviews, phylogenetic reconstruction, biogeography, ecology, physiology, and restoration and conservation questions. Diatom biodiversity main drivers and distribution in tropical reservoirs were investigated from the ecological point of view, and their effects on the diatom datasets separated into different rarity categories were evaluated, evidencing the importance of the latter group that constitutes the major part of the diatom community, but that is usually excluded from the statistical analyses. Current study shows that processes in nature are scale dependent and that dispersion limits may be more important on small scales (< 100 km). In addition, the unaccented study area can be considered an important factor for determination of the relative contribution of the geographic components to the diatom community structure. Finally, it was indicated that high levels of hydrological connectivity favor the organisms exchange through a passive dispersion, thus increasing the similarity of the metacommunities composition and decreasing beta diversity, and consequently demonstrating that hydrological connectivity plays a considerable role in explaining metacommunities dynamics. Consequently, this variable must be not neglected in models that aims at predicting the ecosystem functioning. For conservation purposes, the results suggest large-scale protection, ensuring beta diversity between sites, and conserving total diversity. In addition, development and testing of different biomonitoring approaches are essential to provide information on the current state of freshwater ecosystems.
\nKey words: bioassessment, \u03b2-diversity, phytoplankton, diatom, reservoir, RMSP, surfacesediments.<\/p>\n

RESUMO<\/strong><\/p>\n

As diatom\u00e1ceas (Bacillariophyceae) s\u00e3o algas unicelulares, microsc\u00f3picas, de distribui\u00e7\u00e3o cosmopolita, que ocorrem em diferentes ecossistemas. Sua principal caracter\u00edstica \u00e9 a parede celular bivalve composta quimicamente por s\u00edlica, cuja superf\u00edcie \u00e9 ricamente esculpida e o conjunto das duas valvas de um indiv\u00edduo constitui a fr\u00fastula. Tais algas s\u00e3o sens\u00edveis a uma variedade de fatores ambientais necess\u00e1rios para seu \u00f3timo crescimento sendo, por isso, consideradas excelentes indicadores de mudan\u00e7as que ocorrem nos ecossistemas aqu\u00e1ticos, em especial da eutrofiza\u00e7\u00e3o. Apesar disso, o conhecimento das diatom\u00e1ceas das regi\u00f5es tropicais ainda \u00e9 considerado bastante insuficiente. A atual pesquisa \u00e9 parte do projeto AcquaSed (2010- 2014) e enfoca seis sistemas tropicais e suas comunidades de diatom\u00e1ceas. Para tanto, foram amostrados seis reservat\u00f3rios localizados nas bacias do Alto Paranapanema (tr\u00eas esta\u00e7\u00f5es de amostragem) e do Ribeira do Iguape\/Litoral Sul (17 esta\u00e7\u00f5es de amostragem), situados no sul do Estado de S\u00e3o Paulo. Amostras de \u00e1gua coletadas durante o ver\u00e3o e inverno e de sedimentos superficiais amostrados no inverno foram utilizadas para analisar as caracter\u00edsticas ambientais dos seis reservat\u00f3rios, al\u00e9m de suas respectivas comunidades de diatom\u00e1ceas. Apesar do paradigma estabelecido sobre a dispers\u00e3o ub\u00edqua dos microrganismos, estudos taxon\u00f4micos recentes confirmaram um componente end\u00eamico distintivo na fl\u00f3rula de diatom\u00e1ceas de \u00e1gua doce em diversas localidades ao redor do mundo e, no Brasil, um crescente n\u00famero de trabalhos taxon\u00f4micos contendo descri\u00e7\u00e3o de novas esp\u00e9cies vem sendo publicado. Na presente tese, algumas esp\u00e9cies que ocorrem na \u00e1rea de estudo e relacionadas no banco de dados do projeto AcquaSed s\u00e3o apresentadas como novas com base em an\u00e1lises de microscopia de luz (ML) e eletr\u00f4nica de varredura (MEV), al\u00e9m do suporte de dados ecol\u00f3gicos, da an\u00e1lise de materiaistipo e da compara\u00e7\u00e3o com popula\u00e7\u00f5es de diferentes h\u00e1bitats e ecossistemas. As amostras coletadas nos reservat\u00f3rios brasileiros revelaram uma fl\u00f3rula muito diversa, com esp\u00e9cies desconhecidas e \u00fanicas de diatom\u00e1ceas, que clarificam a import\u00e2ncia de avaliar a identidade e a distribui\u00e7\u00e3o dessas algas nas regi\u00f5es tropicais. A composi\u00e7\u00e3o das comunidades de diatom\u00e1ceas reflete todo um complexo de vari\u00e1veis ecol\u00f3gicas de um local particular. Consequentemente, estudos taxon\u00f4micos e levantamentos flor\u00edsticos n\u00e3o s\u00f3 apoiam projetos de pesquisa aplicada como tamb\u00e9m permitem o monitoramento da qualidade da \u00e1gua, al\u00e9m de uma ampla gama de quest\u00f5es de pesquisa b\u00e1sica de revis\u00e3o e monografias taxon\u00f4micas, reconstru\u00e7\u00e3o filogen\u00e9tica, estudos biogeogr\u00e1ficos, ecol\u00f3gicos, fisiol\u00f3gicos, de restaura\u00e7\u00e3o e conserva\u00e7\u00e3o. Do ponto de vista ecol\u00f3gico, investigou-se os principais direcionadores da biodiversidade e da distribui\u00e7\u00e3o de diatom\u00e1ceas nos seis reservat\u00f3rios e avaliaram-se seus efeitos tamb\u00e9m em conjuntos de diatom\u00e1ceas de diferentes categorias de raridade, evidenciando a import\u00e2ncia desse grupo que comp\u00f5e a maior parte da comunidade, mas que \u00e9, em geral, exclu\u00eddo das an\u00e1lises estat\u00edsticas. O presente estudo mostra que os processos na natureza s\u00e3o dependentes da escala e que os limites da dispers\u00e3o podem ser mais importantes em pequenas escalas (< 100 km). Al\u00e9m disso, a \u00e1rea de estudo n\u00e3o impactada pode ser considerada um fator importante na determina\u00e7\u00e3o das contribui\u00e7\u00f5es relativas dos componentes geogr\u00e1ficos na estrutura da comunidade de diatom\u00e1ceas. Finalmente, exp\u00f4s-se que altos n\u00edveis de conectividade hidrol\u00f3gica favorecem a troca de organismos atrav\u00e9s da dispers\u00e3o passiva, aumentando a similaridade na composi\u00e7\u00e3o das metacomunidades e diminuindo a diversidade beta, demonstrando que a conectividade hidrol\u00f3gica desempenha um papel de capital import\u00e2ncia na explica\u00e7\u00e3o da din\u00e2mica das metacomunidades. Consequentemente, esta vari\u00e1vel n\u00e3o deve ser negligenciada em modelos que predigam o funcionamento do ecossistema. Para fins de conserva\u00e7\u00e3o, os resultados sugerem uma prote\u00e7\u00e3o em grande escala, assegurando a diversidade beta entre s\u00edtios e conservando a diversidade total. Por fim, o desenvolvimento e o teste de diferentes abordagens de biomonitoramento tornam-se fundamentais no fornecimento de informa\u00e7\u00f5es sobre o estado atual dos ecossistemas de \u00e1gua doce.
\nPalavras-chave: bioindica\u00e7\u00e3o, diatom\u00e1cea, diversidade beta, fitopl\u00e2ncton, represa de abastecimento, RMSP, sedimentos superficiais.<\/p>\n

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\"pdf_grande\"<\/a>Gisele Carolina Marquardt<\/strong><\/a>
\nCompara\u00e7\u00e3o da biodiversidade e distribui\u00e7\u00e3o das diatom\u00e1ceas planct\u00f4nicas e de sedimentos superficiais em seis reservat\u00f3rios do sul do Estado de S\u00e3o Paulo<\/a><\/p>\n

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VOLTAR AS DISSERTA\u00c7\u00d5ES E TESES<\/a><\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

Gisele Carolina Marquardt Compara\u00e7\u00e3o da biodiversidade e distribui\u00e7\u00e3o das diatom\u00e1ceas planct\u00f4nicas e de sedimentos superficiais em seis reservat\u00f3rios do sul do Estado de S\u00e3o Paulo ABSTRACT Diatoms (Bacillariophyceae) are cosmopolitan, unicellular, microscopic algae that occur in different ecosystems. Their main morphological feature is the silica built cell wall possessing a rich sculpted surface that constitutes […]<\/p>\n","protected":false},"author":187,"featured_media":0,"parent":249,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/8006"}],"collection":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/users\/187"}],"replies":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/comments?post=8006"}],"version-history":[{"count":2,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/8006\/revisions"}],"predecessor-version":[{"id":8012,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/8006\/revisions\/8012"}],"up":[{"embeddable":true,"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/pages\/249"}],"wp:attachment":[{"href":"https:\/\/www.infraestruturameioambiente.sp.gov.br\/pgibt\/wp-json\/wp\/v2\/media?parent=8006"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}