A influência do sombreamento sobre diferentes atributos da comunidade de algas perifíticas.

Light is an essential component in the process of synthesis of the organic compounds by photosynthetic organisms. We tried to evaluate the influence of this variable on different attributes of the periphythic algae, important producers in the trophic webs of aquatic environments, through an experime...

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Detalhes bibliográficos
Autor: Santos, Helivania Sardinha dos
Formato: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2018
País:Brasil
Recursos:Universidade Estadual de Maringá (UEM)
Repositorio:Repositório Institucional da Universidade Estadual de Maringá (RI-UEM)
Idioma:portugués
OAI Identifier:oai:localhost:1/4952
Acesso em linha:http://repositorio.uem.br:8080/jspui/handle/1/4952
Access Level:acceso abierto
Palavra-chave:Perifíton de água doce
Algas perifíticas
Comunidades, Ecologia de
Luminosidade
Pesquisa experimental
Luz
Biomassa
Densidade
Lago das Garças
Planície de inundação
Alto rio Paraná
Brasil.
Periphyton
Periphythic algae
Light
Biomass
Density
Floodplain
Communities
Ecology
Upper Paraná River
Brazil.
Ciências Biológicas
Ecologia
Descrição
Resumo:Light is an essential component in the process of synthesis of the organic compounds by photosynthetic organisms. We tried to evaluate the influence of this variable on different attributes of the periphythic algae, important producers in the trophic webs of aquatic environments, through an experiment in mesocosmos with different levels of luminosity. In approach 1 we evaluated different levels of shading in the production of biomass of periphytic algae. The biomass was measured using the chlorophyll-a method. The highest biomass was found in the control treatment, not suffering from photoinhibition, while the lowest biomass was found in the treatment with 80% shading. In approach 2 we evaluated the influence of the high level of shading on the process of succession of periphytic algae through the variation of community density over time and between treatments. The community presented changes in its density between the beginning and end of the experiment, in addition to a change in its composition, with the class Bacillariophyceae being the most abundant at the beginning of the process of succession in a high level of shading and in the control treatment (without shading). This remained more abundant in the shade treatment and was replaced by Zygnemaphyceae in the control treatment. The adaptation of these algae due to the mainly photosynthetic pigments and accessories that they present in their constitution, are essential in the process of colonization and succession in the environments. We conclude that light is a variable of extreme importance, exerting direct influence on several attributes of the periphytic community.