Thesis (M.S.)--University of West Florida, 2006. / Title from title page of source document. Document formatted into pages; contains 99 pages. Includes bibliographical references.

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Periphyton are an important group of primary producers in stream ecosystems and are commonly used as indicators of water quality and ecosystem status. Periphyton biomass accumulation in streams is influenced by a number of factors, including nutrient supply, shading by riparian vegetation, substrate properties, and hydrological conditions. Urban land use potentially influences all of these factors in ways that may promote or constrain periphyton growth. Such influences may be further altered by efforts to restore urban streams within parks and residential settings. To test this, I compared patterns of stream periphyton biomass among rural (forested), urban, and restored urban streams within and around Umeå. I found that periphyton biomass varied up to 50-fold among sites but did not differ significantly among stream classes (i.e., rural vs. urban vs. urban restored). Periphyton biomass did tend to increase among sites with greater nutrient concentrations and warmer temperature. Yet, these patterns were influenced by substrate conditions within and among streams, with significantly greater biomass observed on larger cobbles when compared to sand. Results indicate that sedimentation in the studied urban streams (and likely in streams in general) may restrict algal growth, even if other conditions are otherwise favourable. Conversely, urban restoration involving the placement of course substrate on the stream bottom may enhance algal growth locally, particularly where light and nutrients are both elevated. My findings illustrate that periphyton biomass depends on a multi-scale framework of factors that should be considered when managing streams, especially in urban areas where streams are often influenced by both local and catchment-scale stressors.

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Didymosphenia geminata (Didymo) is a nuisance, bloom forming, invasive freshwater algae. Through an ecological survey I examined habitat associations and effects, identifying bloom preferences for stable, low nutrient rivers, often downstream of still waterbodies; with major observed changes to algal and invertebrate communities. Experimental examination of the functional significance of blooms, provided strong support for the hypothesis that blooms are an adaptive, plastic ecophysiological response to nutrient limitation, maximising internal mat cycling and phosphatase based uptake. Further experimentation identified Didymo absence from higher nutrient waterways, is explained by competition with other algae and suppression of the 'bloom' response. Research suggests Didymo is here to stay, but spread management and mitigation will minimise damage to New Zealand's waterways.

Recent studies within the past decade or so have shown the importance of algae in geomorphic and hydrologic processes of lotic systems. However, the ecohydraulic role of algae in bedrock systems has largely been ignored. In addition, the utility of algae as indicators of channel dynamics have often been assumed by geomorphologists, but relatively few studies have examined this relationship. The purpose of this study was to determine whether algae, specifically diatoms, are useful indicators of channel geomorphological dynamics, and to examine if distinct habitats or biotopes typical in fluviokarst and bedrock systems provide unique habitat space for diatoms, and to address the potential ecohydraulic implications. The investigation was performed in a 100 m reach of Shawnee Run, a limestone, fluviokarst tributary to the Kentucky River in Mercer County, KY. The results of the study showed that periphyton are not useful indicators of channel dynamics, and that biotopes and other distinct habitats, including riffles, bedforms, and fine sediment, do not provide unique habitat in terms of diatom community composition.

Thesis (M.S.)--University of Nevada, Reno, 2007. / "December 2007." Includes bibliographical references (leaves 78-84). Online version available on the World Wide Web.

Theses (M.S.)--Marshall University, 2006. / Title from document title page. Includes abstract. Document formatted into pages: contains iv, 45 pages including illustrations. Bibliography: p. 25-26.

Made available in DSpace on 2014-06-11T19:29:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-05-15Bitstream added on 2014-06-13T20:59:39Z : No. of bitstreams: 1 taniwaki_rh_me_bauru.pdf: 1064252 bytes, checksum: 1b3f9a15ac1bed4d1169edc54c9557ce (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O reservatório de Itupararanga representa grande importância na bacia hidrográfica do rio Sorocaba devido aos usos múltiplos que este ecossistema propicia à população. Dentre as diversas atividades que usufruem dos serviços ambientais desse reservatório, podemos citar o abastecimento de água potável, irrigação, recreação, navegação e turismo. Dessa forma, o presente estudo objetivou estudar os estoques de carbono e as relações da comunidade periférica (biomassa e composição específica) com a qualidade da água no reservatório de Itupararanga. Para isso, foram realizadas cinco campanhas de amostragem em quatro estações amostrais ao longo do reservatório em duas espécies de macrófitas aquáticas. A biomassa perifitica aderida às raízes da macrófita aquática. Eichhornia spp. apresentou variação de 0,9 mg.m2 a 12,5 mg.m2 e a biomassa perifitica aderida às raízes da macrófita aquática Polygonum punctatum apresentou variação de 0,5 mg.m2 a 3,9 mg.m2 e mostraram-se controladas principalmente pelo regime hidrológico e pelas concentrações de nutrientes na água. Os estoques de carbono da comunidade perifitica aderida às raízes de Eichhornia spp. e nos pecíolos de P. punctatum variaram de 0,3 mgC.m2 a 2,5 mgC.m2 e 0,1 mgC.m2 a 1,2 mgC.m2 respectivamente. Já em relação à composição específica de algas perifiticas, foi encontrado um total de 156 táxons divididos em 8 classes e a densidade total das espécies variou de 10,2 mil a 171,8 mil indivíduos por milímetro quadrado. Em relação à qualidade da água, o reservatório de Itupararanga apresentou em diversas momentos concentrações acima do máximo permitido para fósforo total e abaixo do mínimo permitido para oxigênio dissolvido segundo a resolução CONAMA 357/2005. A comunidade de algas perifíticas mostrou-se controlada por... / The Itupararanga reservoir has great importance in the Sorocaba River basin due to the multiple uses that uses that this ecosystem provides to the population. Among the many activities that take benefit of the environmental services from this reservoir, we can cite the drinking water supply, irrigation, recreation, navigation and tourism. Therefeore, this study aimed to study the carbon stocks and the relationships of the periphytic community (biomass and species composition) with the quality of the water in the reservoir Itupararanga. For this, five sampling campaigns in four sampling stations along the reservoir in two species of aquatic macrophytes were performed. The periphyton biomass attached to the roots of the aquatic macrophyte Eichhornia spp. presented a variation of 0.9 mg.m2 to 12,5 mg.m2 and periphyton biomass attached to the aquatic macrophyte Polygomum punctatum showed variation of 0,5 mg.m2 to 3.9 mg.m2 and were controleed mainly by the hydrological regime and nutrient concentrations in the water. The periphytic community carbon stocks attached to the roots of eichhornia spp. and the petioles of P. punctatum ranged from 0.3 mgC.m2 to 2.5 mgC.m2 and 0.1 mgC.m2 to 1.2 mgC.m2 respectively. In relation to the species composition of periphytic algae, it has been found a total of 156 taxa divided into eight classes and the overall density of the species ranged from 10,200 to 171,800 individuals per square millimeter. In relation to the water quality, the Itupararanga reservoir performed in several times above the maximum allowed concentrations for total phosphorus and below the minimum allowable concentrations for dissolved oxygen according to CONAMA 357/2005 resolution. The community of periphytic algae has shown to be controlled by spatial and temporal patterns, such as substrate type, the sampling stations... (Complete abstract click electronic access below)

Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-09-15T13:15:36Z No. of bitstreams: 2 Dissertação - Alline Alves França - 2016.pdf: 2005555 bytes, checksum: 84feb7f2b775249a2495d3a742b1ec05 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-15T14:42:25Z (GMT) No. of bitstreams: 2 Dissertação - Alline Alves França - 2016.pdf: 2005555 bytes, checksum: 84feb7f2b775249a2495d3a742b1ec05 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-15T14:42:25Z (GMT). No. of bitstreams: 2 Dissertação - Alline Alves França - 2016.pdf: 2005555 bytes, checksum: 84feb7f2b775249a2495d3a742b1ec05 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-03-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / (Pinnularia Ehrenberg (Bacillariophyta) of pristine streams of Central Brazil). This study aimed to inventory the species of the genus Pinnularia present in pristine streams located in the cerrado biome (Midwest Brazil) between the years 2012 and 2013. The periphyton was collected in five streams in the savannah, in different substrates and seasons. Were identified 23 species, of which 17 are on the 1st occurrence of citations for the Midwest Region: P. angustivalva, P. butantanum, P. castraregina, P. divergens var. biconstricta, P. divergens var. mesoleptiformis, P. divergens var. protracta, P. gibba var. subundulata, P. meridiana var. meridiana, P. microstrauron var. rostrata, P. paulensis, P. persudetica var. persudetica, P. subgibba var. angustarea, P. subgibba var. capitada, P. superpaulensis, P. viridiformis var. minor and P. undula var. undula. Taxa that had a higher frequency of occurrence in the studied streams were P. subanglica, P. angustivalva, P. brauniana and P. butantanum. / (Pinnularia Ehrenberg (Bacillariophyta) de córregos prístinos do Brasil Central). Este estudo objetivou inventariar as espécies do gênero Pinnularia presentes em córregos prístinos localizados no bioma cerrado (Centro-Oeste do Brasil) entre os anos de 2012 e 2013. O perifíton foi coletado em cinco córregos no cerrado, em diferentes substratos e períodos sazonais. Foram identificadas 23 espécies, sendo que 17 são primeiras citações de ocorrência para a Região Centro-Oeste: P. angustivalva, P. butantanum, P. castraregina, P. divergens var. biconstricta,P. divergens var. mesoleptiformis, P. divergens var. protracta, P. gibba var. subundulata, P. meridiana var. meridiana, P. microstrauron var. rostrata, P. paulensis, P. persudetica var. persudetica, P. subgibba var. angustarea, P. subgibba var. capitada, P. superpaulensis, P. viridiformis var. minor e P. undula var. undula. Os táxons que tiveram maior freqüência de ocorrência nos córregos analisados foram P. subanglica, P. angustivalva, P. brauniana e P. butantanum.