Ecologia de algas perifíticas em uma lagoa costeira com múltiplos usos (lagoa Juara, Serra, ES)

• Ano de defesa: 2011
• Autor(a) principal: Almeida, Stéfano Zorzal de
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Biologia Vegetal; UFES; Programa de Pós-Graduação em Biologia Vegetal
• Palavras-chave em Português: Periphyton; Fish farming; Municipal sewage; Biomass; Community structure; Piscicultura; Efluente doméstico; Estrutura da comunidade; Peixe - Criação; Perifíton - Juara, Lagoa (ES); Biomassa - Juara, Lagoa (ES); Agronomia; 57
• Link de acesso: http://repositorio.ufes.br/handle/10/9992

Coastal lagoons are shallow water bodies, usually oriented parallel to the coast and are often impacted by human activities. Juara lagoon (Serra, Brazil) is a shallow coastal environment that has multiple uses such as recreation, fishing and intensive aquaculture. Displays tributaries that convey untreated effluents. This study aimed to evaluate periphyton responses in two sampling sites subject to different human impacts. Three experimental structures containing artificial substrates (glass plates) were implanted at two sampling sites in Dec/2009: TR - within the intensive fish (net cage); and ED - near the mouth of the Laranjeira creek, disseminator of wastewater, and the headquarters of the Associação de Pescadores. Plants were sampled in each of the experimental structures after 21, 26 and 31 days of succession. Were evaluated: transparency, conductivity, pH, turbidity, total suspended solids, alkalinity, dissolved oxygen, water temperature, total nitrogen, nitrate, nitrite, ammonia nitrogen, total phosphorus, orthophosphate and silicate. The periphyton scrapings was analyzed by the following attributes: density (total and per class), richness (total and per class), biovolume (total and per class), diversity, evenness, abundance, dominance, photosynthetic pigments (chlorophyll a and b and carotenoid) pheophytin, dry weight and ash-free dry weight. The two sampling sites showed eutrophic characteristics, with ED had higher electrical conductivity, turbidity, total suspended solids, total alkalinity, total nitrogen, nitrate, ammonia nitrogen and orthophosphate. TR were recorded higher values for water temperature, water transparency and silicate. Density and total biovolume showed no differences between sampling sites. Bacillariophyceae were significantly higher at station TR for density and biovolume. Coscinodiscophyceae and Cyanophyceae density and biovolume were significantly higher in ED. Richness (total and per class), diversity, chlorophyll b, carotenoids, pheophytin, dry weight and ash-free dry weight showed no significant difference between the sampling stations. Chlorophyll a was higher at station ED. Impacts caused different responses in different periphytic community, especially in terms of their composition.