Aspectos taxonômicos e amplitude ecológica de Schizomeris leibleinii (Chaetophorales, chlorophyta)
Carregando...
Data
2004-02-27
Autores
Pereira, Jeferson Luizi [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Schizomeris leibleinii Kützing (Chaetophorales, Chlorophyta) é uma espécie algal comumente encontrada em ambientes aquáticos continentais eutrofizados ou poluídos por nutrientes orgânicos. Trata-se de uma alga filamentosa, desprovida de ramificações que apresenta sistema basal de fixação diferenciado. Os filamentos jovens são finos e unisseriados com células regulares, enquanto os filamentos mais velhos são espessos e multisseriados com células irregulares. Além de S. leibleinii, o gênero Schizomeris inclui outras duas espécies, S. irregularis Fritsch & Rich e S. indicum (como Uronema indicum Ghose), deficientemente caracterizadas. Sugere-se que o sistema basal de fixação seria uma característica confiável na distinção entre as possíveis espécies. Devido ao hábitat onde geralmente se encontra (eutrofizado), S. leibleinii apresenta grande potencial como um bom organismo indicador de poluição orgânica. O conhecimento de sua biologia e de sua capacidade de tolerância às condições ambientais torna-se importante para projetos futuros de biomonitoramento ou indicação das condições tróficas de águas continentais. Para tanto é também necessário o esclarecimento correto sobre a taxonomia do gênero. Estudos taxonômicos foram realizados a partir de análises da variação morfométrica e morfológica entre indivíduos de onze populações espacialmente distintas e entre indivíduos de duas populações avaliadas mensalmente. Além desta abordagem, análises de características cariológicas e da zoosporogênese também foram avaliadas para complementar as informações necessárias à avaliação taxonômica. Dados da variação morfométrica e morfológica foram tratados estatisticamente pelos testes de ANOVA - uma via, t de Student e análise de grupamento para se verificar as diferenças entre as características morfológicas...
Schizomeris leibleinii Kützing (Chaetophorales, Chlorophyta) is an algal species commonly found in continental aquatic environments that are eutrophic or polluted by organic nutrients. It is a filamentous alga, without ramifications, that presents a differentiated basal attachment system. The young filaments are thin and uniseriate with regular cells, while the oldest filaments are thick and multiseriate with irregular cells. Besides S. leibleinii, the genus Schizomeris contains two other species, S. irregularis Fritsch & Rich and S. indicum (Ghose) Fritsch & Rich, deficiently characterized. It is suggested that the basal attachment system would be a reliable characteristic of distinction among the species. Due to the habitat where it is usually found (eutrophic), S. leibleinii shows high potential as a good indicator of organic pollution. The knowledge of its biology and tolerance to the environmental conditions is important for future projects of biomonitoring or indication of the trophic conditions of continental waters. To that, it is necessary to correctly discern about the taxonomy of the genus. Taxonomic studies were conducted by the analyses of morphometrical and morphological variation of the filaments in eleven spatially distinct populations and among specimens from two different populations monthly evaluated. In addition, analyses of karyological characteristics and of the zoosporogenesis were proceeded to complement the necessary information to taxonomic assessment. The data of the morphometrical and morphological variation were evaluated by ANOVA (one way), Student's t-test and cluster analysis to verify the differences between the morphological characteristics of the different populations and their relationships with the taxonomy of the species. Environmental parameters were collected in the monthly-evaluated populations and submitted to the Pearsonþs correlation (r)...(Complete abstract click electronic access below)
Schizomeris leibleinii Kützing (Chaetophorales, Chlorophyta) is an algal species commonly found in continental aquatic environments that are eutrophic or polluted by organic nutrients. It is a filamentous alga, without ramifications, that presents a differentiated basal attachment system. The young filaments are thin and uniseriate with regular cells, while the oldest filaments are thick and multiseriate with irregular cells. Besides S. leibleinii, the genus Schizomeris contains two other species, S. irregularis Fritsch & Rich and S. indicum (Ghose) Fritsch & Rich, deficiently characterized. It is suggested that the basal attachment system would be a reliable characteristic of distinction among the species. Due to the habitat where it is usually found (eutrophic), S. leibleinii shows high potential as a good indicator of organic pollution. The knowledge of its biology and tolerance to the environmental conditions is important for future projects of biomonitoring or indication of the trophic conditions of continental waters. To that, it is necessary to correctly discern about the taxonomy of the genus. Taxonomic studies were conducted by the analyses of morphometrical and morphological variation of the filaments in eleven spatially distinct populations and among specimens from two different populations monthly evaluated. In addition, analyses of karyological characteristics and of the zoosporogenesis were proceeded to complement the necessary information to taxonomic assessment. The data of the morphometrical and morphological variation were evaluated by ANOVA (one way), Student's t-test and cluster analysis to verify the differences between the morphological characteristics of the different populations and their relationships with the taxonomy of the species. Environmental parameters were collected in the monthly-evaluated populations and submitted to the Pearsonþs correlation (r)...(Complete abstract click electronic access below)
Descrição
Palavras-chave
Alga, Ecologia aquatica, Poluição, Pollution
Como citar
PEREIRA, Jeferson Luizi. Aspectos taxonômicos e amplitude ecológica de Schizomeris leibleinii (Chaetophorales, chlorophyta). 2004. v, 90 f. Dissertação (mestrado) - Universidade Estadual Paulista, Instituto de Biociências de Rio Claro, 2004.