Distribuição vertical da comunidade fitoplanctônica do lago dos Tigres (Goiás, Brasil)

Abstract

Tigres Lake is a blocked valley lake, with no registered studies of phytoplankton vertical distribution for that lake type; as such, our work assumes a pioneering nature. The aim of this study was to recognize temporally and spatially the vertical patterns of phytoplankton community attributes, to detect the dominant and descriptive phytoplankton functional groups, and relate them to limnological characteristics. Tigres Lake was characterized as a warm polymictic lake, featuring occasional thermal stratification in deeper stations. The dry and early rainy seasons presented limnological (evidenced by PCA) and biological (observed by CCA) differences. The dry months presented more nutrient concentrations and greater transparency level; on those months, phytoplankton functional groups Lo, Y, N and W1 were predominant; while the rainy months featured higher temperatures and lower transparency levels, and the predominant phytoplankton functional groups were S1, T and N. By jointly evaluating limnological characteristics, biovolume and phytoplankton functional groups, it can be concluded that the vertical profile of Tigres lake is oligo-mesotrophic.