Norint įvertinti vandens telkinio būklę, pakanka patyrinėti kurią nors gyvųjų organizmų grupę. Viena iš tokių indikatorinių sistematinių grupių yra titnagdumbliai (Bacillariophyceae). Dauguma tyrėjų teigia, kad titnagdumbliai yra idealūs indikatoriai biologiniam monitoringui, nes didelis skaičius ekologiškai jautrių rūšių tiek vandenyje, tiek nuosėdose, tiksliai nusako esamą ekologinę situaciją (Dixit et al. 1992). Aulacoseira granulata, Fragilaria crotonensis, Asterionella formosa, Cyclotella sp. Synedra sp. Rhizosolenia sp., Diatoma, Achnanthes, Cyclotella, Stephanodiscus dažnos mezotrofiniuose vandens telkiniuose. Stephanodiscus hantzschii intensyvus vystymasis vandens telkinyje yra aukšto trofiškumo rodiklis bei užterštumo organinėmis medžiagomis indikatorius. Apskritai, išskyrus Stephanodiscus sp., titnagdumbliai stipriai eutrofinių ir hipertrofinių sąlygų ežere nepakenčia. / As is well known as a better state of body water, the more species of living organisms can live in it, and the deterioration of water quality, with a consequent reduction in plant and soil or water surface the number of living species. It remains only for not demanding, resistant to water pollution types. So in order to assess the water situation, it is sufficient to explore any group of living organisms. One such indicator is the systematic group of diatoms (Bacillariophyceae). Aulacoseira granulata, Fragilaria crotonensis, Asterionella formosa, Cyclotella sp. Synedra sp. Rhizosolenia sp., Diatoma, Achnanthes, Cyclotella, Stephanodiscus common in mesotrophic waters. Intensive development of Stephanodiscus hantzschii in water body is a high trophic rate and contamination of organic matter indicator. In general, except for Stephanodiscus sp. diatoms can not stand strongly eutrophic and hypertrophic conditions in the lake.

Lagunas são corpos de águas interiores, frequentemente orientados em posição paralela à linha de costa, e conectadas ao oceano por um ou mais restritos canais, características essas que as distinguem dos estuários. No sul do Brasil é escasso a ocorrência de ambientes lagunares, sendo os mesmos conhecidos pelo nome de lagoa, entre eles, a Lagoa do Peixe, que está inserido no Parque Nacional da Lagoa do Peixe. Este parque possui status de Reserva da Biosfera da Mata Atlântica, Sítio Ramsar e é parte da Rede Hemisférica de Reservas das Aves Limícolas Migratórias, por se constituir em importante refúgio de aves migratórias do Hemisfério Sul. O fato das lagunas serem sistemas de baixa profundidade, de mistura da coluna d´água, de alta reciclagem de matéria e nutrientes são altamente produtivas e as comunidades fitoplanctônica e microfitobêntica, esta última constituída predominantemente por diatomáceas, desempenham um papel fundamental. Apesar da importância ecológica da Lagoa do Peixe, a sua comunidade de diatomáceas bentônicas é muito pouco conhecida. O estudo teve como objetivos ampliar o conhecimento da composição taxonômica de diatomáceas bentônicas no sistema e entender a variação espacial e sazonal de atributos da comunidade em relação às variáveis ambientais, em um ciclo anual. Amostragens de sedimento foram efetuadas nas margens da porção Norte, Centro e Sul da lagoa, nas diferentes estações do ano, entre junho de 2011 e fevereiro de 2012. Este estudo demonstrou que a comunidade de diatomáceas esteve representada por 62 táxons, distribuídos em 30 gêneros e 20 famílias, sendo composta por espécies salobras e marinhas, com poucos representantes de água doce. Os gêneros que apresentaram maior número de táxons foram Amphora Ehrenb. ex Kütz, Nitzschia Hassall e Diploneis Ehrenb. ex P.T. Cleve. A riqueza, diversidade e equitabilidade) das diatomáceas apresentaram variações no espaço e no tempo. Maiores valores destes atributos foram encontrados na porção Norte da lagoa e na estação do outono. As variações estiveram relacionadas com as variáveis salinidade, temperatura, pluviosidade e ação do vento. São apresentadas 228 ilustrações das espécies com base na análise em microscópios ópticos e eletrônicos. Informações sobre as dimensões, ecologia e distribuição dos táxons também são incluídas. O total de 74% das espécies são primeiras citações para a Lagoa do Peixe, o que demonstra um aporte significativo ao conhecimento da biodiversidade neste sistema lagunar. O estudo taxonômico das diatomáceas neste sistema permitiu também ampliar a diagnose de Cocconeis sawensis Al-Handal et Riaux- Gobin, com base na observação do material tipo, oriundo de um lago salino do Iraque e verificar a ocorrência de variações morfológicas na população de Falcula hyalina Takano. / Lagoons are bodies of inland waters, often parallel to the coastline, and connected to the ocean by one or more restricted channels, which distinguish them from estuaries. In the south of Brazil there are a few lagoon environments, which are known as of Lakes (Lagoas), among them the Lagoa do Peixe, which is part of the Lagoa do Peixe National Park. This park is a Atlantic Forest Biosphere Reserve, Ramsar Site and is part of the Western Hemisphere Shorebird Reserve Network, for being an important refuge for migratory birds in the Southern Hemisphere. The fact that the lagoons are shallow with water column mixing, high-recycled matter and nutrients, the phytoplankton and microphytobenthic communities are highly productive, with the latter composed predominantly of diatoms, fundamental in thi system. Despite the ecological importance of the Lagoa do Peixe, its community of benthic diatoms is little known. The objective of this study was to increase the knowledge of the composition of benthic diatoms in the system and to understand the spatial and seasonal variation of community attributes in relation to environmental variables over an annual cycle. Sediment samples were taken on the shores of the North, Center and South portion of the lagoon, in different seasons of the year, between June 2011 and February 2012. This study showed that the diatom community was represented by 62 taxa, distributed in 30 genera and 20 families, composed mostly of brackish and marine species, with few representatives of fresh water. The genera with the greatest number of taxa were Amphora Ehr. ex Kütz, Nitzschia Hassall and Diploneis Ehr. ex P.T. Cleve. The richness, diversity and equitability of the diatoms varied in space and time. Higher values of these attributes were found in the northern portion of the lagoon and in fall. The variations were related to salinity, temperature, rainfall and wind action. Illustration of 228 species using light and electron microscopy are presented. Information on the dimensions, ecology and distribution of taxa are included. A total of 74% of the species are first reports for Lagoa do Peixe, which demonstrates a significant contribution to the knowledge of biodiversity in this lagoonal system. The taxonomic study of the diatoms in this system also made it possible to increase the diagnosis of Cocconeis sawensis Al-Handal et Riaux-Gobin, based on the observation of the type material from a saline lake in Iraq, and to verify the occurrence of morphological variations in the population of Falcula hyalina Takano.

Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-11-22T18:07:16Z No. of bitstreams: 2 Cinthia_Favaretto_2018.pdf: 2179148 bytes, checksum: ecff784c58c19dda7ee6b23ade555ce2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-22T18:07:16Z (GMT). No. of bitstreams: 2 Cinthia_Favaretto_2018.pdf: 2179148 bytes, checksum: ecff784c58c19dda7ee6b23ade555ce2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-04-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Eunotia species from a stream located in the surrounding area of the Iguaçu National Park conservation unit was analyzed. Samples were monthly collected from September 2012 to August 2013. The periphytic material, manually obtained by squeezing an aquatic macrophyte, was oxidized and analyzed under optical and scanning electron microscopy. Twenty-one infrageneric taxa of Eunotia were identified, measured, and illustrated. Eunotia caniculoides Favaretto, Tremarin, Bueno & T. Ludwig is proposed as a new species, and eight taxa are new records for the state of Paraná: E. georgii Metzeltin & Lange-Bertalot, E. glacialifalsa Lange-Bertalot, E. guianense (Ehrenberg) de Toni, E. pileus Ehrenberg, E. pseudoimplicata Lange-Bertalot, L.F.Costa & C.E.Wetzel, E. pseudosudetica var. rotundata Cavalcante, Tremarin & T.Ludwig, E. sedina Lange-Bertalot and E. tropico-arcus Metzeltin & Lange-Bertalot. Keywords: Bacillariophyta, Diatoms, Periphyton, Southern Brazil, Taxonomy. / Espécies de Eunotia Ehrenberg de um ambiente lótico localizado em área adjacente à unidade de conservação Parque Nacional do Iguaçu foi analisada. As coletas foram realizadas mensalmente de setembro de 2012 a agosto de 2013. O material perifítico obtido do espremido manual de uma macrófita aquática foi oxidado e analisado sob microscopia óptica e eletrônica de varredura. Vinte e um táxons infragenéricos foram identificados, medidos e ilustrados. Eunotia caniculoides Favaretto, Tremarin, Bueno & T. Ludwig é proposta como uma nova espécie e oito táxons constituem novos registros para o estado do Paraná: E. georgii Metzeltin & Lange-Bertalot, E. glacialisfalsa Lange-Bertalot, E. guianense (Ehrenberg) de Toni, E. pileus Ehrenberg, E. pseudoimplicata Lange-Bertalot, L.F.Costa & C.E.Wetzel, E. pseudosudetica var. rotundata Cavalcante, Tremarin & T.Ludwig, E. sedina Lange-Bertalot e E. tropico-arcus Metzeltin & Lange-Bertalot

Diatoms (Bacillariophyta) are one of the most diverse algal groups in the Antarctic Region and play a dominant role in almost all freshwater and terrestrial ecosystems. Despite this overall occurrence, little is known about the diversity, ecology and biogeography of this group in the Maritime Antarctic Region. The main objective of this thesis is therefore to define the taxonomical, ecological and biogeographical characterisation of aquatic, semi- aquatic and moss-inhabiting diatom communities from two islands in the Maritime Antarctic Region: James Ross Island and Livingston Island, located on opposite sides of the Antarctic Peninsula. In this study, a total of 250 samples from three different habitat types (lakes, streams & seepage areas and mosses) from Byers Peninsula (Livingston Island) and Ulu Peninsula (James Ross Island) have been analysed. Using light and scanning electron microscopy, a rather diverse diatom flora composed of 178 taxa, belonging to 43 genera has been identified. Although even until recently, it was generally accepted that the Antarctic diatom flora was mostly composed of cosmopolitan taxa, several new species could be described as a new for science during this PhD study (a reflection of this work is presented in chapters 2 & 3 and in Appendices). Habitat type and...

In Antarctica, diatoms inhabit multiple limno-terrestrial habitat types, which may each individually offer unique ecological information for use in biomonitoring, paleoecology, and biogeography. However, we are still at the initial exploration stage of documenting the diversity among habitat types from different Antarctic regions, which is necessary to serve as baseline data for the aforementioned scientific disciplines, and ultimately inform conservation decisions. To gain insight into the spatial and habitat controls on Antarctic diatom communities, the importance of habitat type and island aspect was investigated by studying diatoms living in ponds, mosses, streams, and seepage areas on two opposite sides Vega Island, Antarctic Peninsula. A diverse flora of 136 taxa belonging to 31 genera was revealed, which was dominated by the genus Nitzschia, and suggests that the flora of Vega Island is biogeographically influenced by both continental and Maritime Antarctic bioregions. Habitat type was found to be a crucial factor for diatom community composition, and was stronger than the influence of island aspect. In ordination analyses, moss samples were separated primarily by their abundances of the diatom Chamaepinnularia krookiformis, while pond samples were separated by Nitzschia paleacea and stream...