Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 31-38).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1976. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Bibliography: leaves G-10-12.

For the first time, presented within this thesis, is an investigation into the species richness and community composition of a group of beautiful but taxonomically challenging green algae - the desmids. This thesis represents the first account of a systematic sampling approach for desmid species and community assemblages in relation to national and local environmental variation. Sampling was focused on intact blanket mire with the aim of capturing a rich baseline dataset of desmid diversity. Previous works had highlighted desmids as being especially species rich in these acidic, nutrient-poor peatland habitats. A nested sampling approach was used to collect desmids from blanket mire microhabitats along the hummock-pool microtopographic gradient, from sites nationally within Scotland. This approach revealed remarkable species richness with 202 taxa sampled, including one new species. Distinct desmid communities were found to be strongly associated with the hummock-lawn-pool microhabitats within patterned blanket mire. This topographic aspect of peatland structure and its associated co-variables (such as pH and water table depth) also have a strong link to desmid diversity with the richest communities being found in association with a consistent supply of water close to the water table. Generally, ‘unstable' habitats supported lower desmid diversity. A field experiment was established to investigate the effects of drainage and drain restoration on desmid communities. This highlighted the loss of desmid diversity in drained peatlands and a successful but slow recovery of diversity upon restoration through drain blocking. The findings of this PhD project provide an understanding of the spatial scale of desmid community structure and the factors which are important for informing future conservation strategies for peatland habitats to maintain the diversity of this fascinating microbial group.

Thesis (Ph. D.)--Ohio State University, 1929. / Biography. Descriptive letterpress on versos facing the plates. "Papers from the Department of Botany, Ohio State University, no. 258." "Reprinted from Transactions of the American Microscopical Society, vol. XLIX, no. 2, April, 1930." "Literature cited": p. 126-131.

Algal collections from eight lakes in southwestern British Columbia have been examined. The desmid flora consists of 205 species and 44 varieties in 26 genera. Two genera, Spino-closterium and Spinocosmarium, and several species of other genera, are reported for the first time from British Columbia. Seasonal changes in the abundance and kinds of desmids occurring in collections are noted. Cultural studies on the variability of Triploceras gracile and T. verticillaturn were undertaken to determine the validity of subspecific characters used in the genus. These studies showed that the apical radiation of the semicell (the number of lobes at the end of the semicell) can vary from biradiate (2-lobed) to quadriradiate (4-lobed) within a single clone. Thus in the genus this character must be discarded as a taxonomic criterion. The morphology of the protuberances of the semicells was constant in both species, and is a useful subspecific character. A number of abnormal forms occurred in cultures but were not observed in field collections. The nuclear cytology of Triploceras was investigated. T. verticillaturn has the largest chromosomes yet reported for the Desmidiaceae, almost 20 u in length measured at late prophase in colchicine treated cells. The chromosome number for this species is n = 15-20. The chromosomes of T. gracile are smaller, but no chromosome counts were obtained for this species. / Science, Faculty of / Botany, Department of / Graduate

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-01-31T21:35:05Z No. of bitstreams: 1 DISSERTA??O_Maria AparecidadosSantos.pdf: 7499742 bytes, checksum: b24b188cc992f49fe51406958dcff347 (MD5) / Made available in DSpace on 2017-01-31T21:35:05Z (GMT). No. of bitstreams: 1 DISSERTA??O_Maria AparecidadosSantos.pdf: 7499742 bytes, checksum: b24b188cc992f49fe51406958dcff347 (MD5) Previous issue date: 2016-03-30 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / (Micrasterias C.Agardh ex Ralfs emend. ?kaloud, Nemjov?, Vesel?, Cerna & Neustupa (Desmidiaceae, Conjugatophyceae) of Metropolitan Region of Salvador, Bahia, Brazil).This work is a contribution to the knowledge of Micrasterias biodiversity in metropolitan region of Salvador (MRS). The floristic survey was based on 269 samples collected from 13 municipalities of the MRS, of which 133 came from samples deposited in Herbarium (HUEFS), collected from 2007 to 2009, and 136 collected in 2014-2015, specifically for this study. All sampling sites were georeferenced. Planktonic samples were collected with a plankton net with 20?m mesh while periphytic samples by squeezing submerged parts of aquatic macrophytes. The floristic similarity between the municipalities was based on Similarity Score Jaccard and construction of dendrogram based on the group average (UPGMA). In addition to a dichotomous key to identify the species in the MRS, the following data are provided for each taxon: reference to the original description, description, geographic distribution in Brazil, comments and illustrations. In MRSMicrasterias was represented by 31 taxa distribuited in 20 species, 12 varieties that are not the typical of their respective species and two taxonomic forms also not typical, however, of their respective varieties. Among the taxa identified M. furcata var. dichotoma, M. novae-terrae and M. rotata var. rotata f. evoluta are cited for the first time to Brazil, and M. radians is a new addition to the Bahia State. Among all municipalities studied, only Madre de Deus and Sim?es Filho had no representative of Micrasterias while nine municipalities had the first record of genus.The taxa greater absolute frequency of occurrence in MRS were Micrasteriaslaticeps var. laticeps (969 specimens), M. truncata var. pusilla (858), M. pinnatifida var. pinnatifida (838) and M. radians (546).Micrasterias laticeps var. laticeps and M. pinnatifida var. pinnatifida had wide geographical distribution in RMS, and also displayed a great morphological variation. According to the overall frequency of occurrence of taxa studied it was found that most were rare (71%) and M. pinnatifida var. pinnatifidawas the only taxon considered frequent in the study area. It was observed that the wealth of Micrasterias depending on the location of the water body, thus, the number of taxa was higher in water bodies located in the coastal strip (28) than in those located in the interior (23). Cama?ari was the municipality with the highest taxonomic richness, registering 83.8% of the taxa present in the MRS, followed by Mata de S?o Jo?o (61.3%) and Vera Cruz (58%). The municipalities that had the highest similarity taxonomic were Candeias and S?o Sebasti?o do Pass? (90%), followed by Cama?ari and Mata de S?o Jo?o (75%). The results of this study show that although strong environmental pressure, the MRS is still holds a great biodiversity, but demand for its preservation, actions to mitigate effects of pollution of water bodies present in the area. / (Micrasterias C.Agardh ex Ralfs emend. ?kaloud, Nemjov?, Vesel?, Cerna & Neustupa (Desmidiaceae, Conjugatophyceae) da Regi?o Metropolitana de Salvador, Bahia, Brasil). O presente trabalho constitui uma contribui??o para o conhecimento da biodiversidade de Micrasterias da Regi?o Metropolitana de Salvador (RMS).O levantamento flor?stico foi baseado em 269 amostras coletadas em 13 munic?pios da RMS, das quais 133 provieram de material depositado em Herb?rio (HUEFS), coletadas no per?odo de 2007 a 2009, e 136 coletadas em 2014 a 2015, especificamente para o presente estudo. Todos os locais amostrados foram georreferenciados. As amostras planct?nicas foram obtidas com rede de pl?ncton com abertura de malha de 20?m e as perif?ticas por meio do espremido manual de macr?fitas aqu?ticas. A similaridade flor?stica entre os munic?pios foi calculada com base no ?ndice de Similaridade de Jaccard e constru??o de dendrograma baseado na m?dia de grupo (UPGMA). Al?m de uma chave dicot?mica para identifica??o das esp?cies na RMS, s?o fornecidos os seguintes dados para cada t?xon: refer?ncia da descri??o original, descri??o, distribui??o geogr?fica no Brasil, coment?rios e ilustra??es. Na RMS o g?nero Micrasterias esteve representado por 31 t?xons distribu?dos em 20 esp?cies, 12 variedades que n?o s?o as t?picas de suas respectivas esp?cies e duas formas taxon?micas igualmente n?o t?picas, por?m, de suas respectivas variedades. Dentre os t?xons identificados M. furcata var. dichotoma, M. novae-terrae e M. rotata var. rotata f. evoluta s?o cita??es pioneiras para o Brasil, e M. radians ? adi??o para o estado da Bahia. De todos os munic?pios estudados apenas Madre de Deus e Sim?es Filho n?o tiverem representante de Micrasterias, e nove munic?pios tiveram o primeiro registro do g?nero. Os t?xons com maior n?mero de esp?cimes na RMS foram: Micrasterias laticeps var. laticeps (969 esp?cimes), M. truncata var. pusilla (858), M. pinnatifida var. pinnatifida (838) e M. radians (546). J? Micrasterias laticeps var. laticeps e M. pinnatifida var. pinnatifida apresentaram ampla distribui??o geogr?fica na RMS, tendo tamb?m apresentado grande varia??o morfol?gica.De acordo com a frequ?ncia global de ocorr?ncia dos t?xons estudados constatou-se que a maioria foi enquadrada como rara (71%), e M. pinnatifida var. pinnatifida o ?nico t?xon frequente na ?rea de estudo. Constatou-se que a riqueza de Micrasterias varia em fun??o da localiza??o do corpo aqu?tico, assim, o n?mero de t?xons foi maior nos corpos d??gua situados na faixa litor?nea (28) do que nos localizados no interior (23). Cama?ari foi o munic?pio com a maior riqueza taxon?mica, registrando 83,8% dos t?xons presentes na RMS, seguido por Mata de S?o Jo?o (61,3%) e Vera Cruz (58%). Os munic?pios que apresentaram a maior similaridade taxon?mica foram Candeias e S?o Sebasti?o do Pass? (90%), seguidos por Cama?ari e Mata de S?o Jo?o (75%).Os resultados do presente estudo mostraram que apesar da forte press?o ambiental, a RMS ainda ? detentora de uma grande biodiversidade, mas que demanda, para sua preserva??o, a??es de mitiga??o dos efeitos da polui??o dos corpos d??gua presentes na ?rea.