Structural and successional variability of periphytic algal community in a Amazonian lake during the dry and rainy season (Rio Branco, Acre)

Abstract

The colonization process and successional patterns of a periphytic algal community were evaluated in a Amazonian Viveiro Lake (Rio Branco, Acre, Brazil). Sampling was performed over a period of 35 days; at four-day intervals for 20 days, and then at five-day intervals. Water sampling for physical, chemical and biological analyses was done during the dry and rainy season. Glass slides were used as artificial substrates for periphyton colonization. The structural community was evaluated through population density, algae class, diversity indices and descriptive species. Species richness, diversity and evenness increased as succession progressed. While density of Bacillariophyceae, Euglenophyceae and Zygnemaphyceae increased with succession, Cyanobacteria remained dominant. Synechocystis aquatilis, Synechocystis diplococcus and Navicula pseudolanceolata were the main descriptive species in both the dry and rainy season. Cymbela tumida, Frustulia rhomboides, Trachelomonas lacustris and Closterium acicularis was correlated with an increase in hydrologic level during the rainy season. Conversely, the density of Chlamydomonas sp., Chroomonas nordstedtii, Trachelomonas volvocinopsis, Trachelomonas volvocina and Synechococcus linearis was correlated with an increase in water transparency during the dry season. In general, the periphytic algal community showed high diversity and species richness independent of season. Season also had little influence on representation of algae class and main descriptive species. However, successional patterns varied by season, and changes in hydrologic levels acted directly on the succession path of periphytic algae. More research on periphyton dynamics is needed to improve our understanding of tropical lake ecosystems, especially in Amazonian. Keywords: Periphyton, colonization, succession, diversityVariação estrutural e sucessional da comunidade de algas perifíticas em lago amazônico durante o período seco e chuvoso resumo A colonização e o modelo sucessional da comunidade de algas perifíticas foram avaliados no amazônico Lago do Viveiro (Rio Branco, Acre, Brasil). Amostragens foram realizadas no período de 35 dias com intervalos de quatro dias nos primeiros 20 dias e cinco dias no final. Foram realizadas amostragens da água para a determinação das variáveis físicas, químicas e biológicas no período seco e chuvoso. Lâminas de vidro foram usadas para a colonização do perifíton. A estrutura da comunidade foi avaliada através da densidade populacional, classes algais, índices de diversidade e espécies descritoras. A riqueza de espécies, diversidade e equitabilidade aumentaram com o avanço da sucessão. A densidade de Bacillariophyceae, Euglenophyceae e Zygnemaphyceae aumentaram com o avanço da sucessão, mas Cyanobacteria permaneceu dominante. Synechocystis aquatilis, Synechocystis diplococcus e Navicula pseudolanceolata foram descritoras da comunidade no período seco e chuvoso. Cymbela tumida, Frustulia rhomboides, Trachelomonas lacustris e Closterium acicularis foram correlacionadas...

Periphytic algae dynamics in lentic ecosystems in the Brazilian semiarid

“…Results similar, has been documented by several authors in tropical in tropical reservoirs (e.g. Cavati and Fernandes, 2008;Fernandes et al, 2009;França et al, 2011).…”

Periphyton biomass on artificial substrates during the summer and winter

“…Regardless of the substrate used, it was observed a cumulative increase in the periphytic biomass production in all substrates in the summer period. The spatial sequence which is presented by the periphyton community (FRANÇA et al, 2011) and its relationship with the substrates available for development (PELLEGRINI and FERRAGUT, 2012) can be infl uenced in the composition and, therefore, in the periphytic community biomass.…”

“…It was still observed during the winter that the black plastic and wood substrates presented the best cumulative periphyton production results, highlighting the differences between the substrate's performances in the summer and winter. These differences are closely related to climatic conditions, such as temperature, photoperiod, and the rainy season (GUARIENTO et al, 2009;FRANÇA et al, 2011) which altogether interfere directly in the predominance of species (FELISBERTO & ROFDRIGUES, 2010), and hence, their favorable habitat conditions (PELLEGRINI & FERRAGUT, 2012). The periphytic biomass is directly related to the characteristics and composition of the substrate used for their development (ZHANG et al, 2012), the water fl ow (PELLEGRINI & FERRAGUT., 2012), the brightness, physical, and chemical characteristics of the water (AZIM et al, 2002) such as the concentration of chemical compounds (FELISBERTO & RODRIGUES, 2010).…”

“…The periphytic community contributes signifi cantly in the food supply for aquatic organisms (ASADUZZAMAN et al, 2009;FRANÇA et al, 2011). It can be an important source of low cost food for these animals (UDDIN et al, 2007) and is ecologically appropriate because it does not generate pollution and serves as an indicator of the water quality.…”

Variação sazonal e sucessional da comunidade de algas perifíticas em substrato natural em um reservatório mesotrófico tropical

“…McCormick & Stevenson 1991) e, principalmente, em substrato inerte (ex. Sekar et al 2004;França et al 2011). Em relação ao substrato natural, os estudos abordaram as assembléias algais em termos de especificidade (ex.…”