Phytoplankton structure and dynamics in a volcanic lake in Deception Island (South Shetland Islands, Antarctica)

• Main Authors: Llames, M.E., Vinocur, A.
• Format: Journal/Newspaper
• Language: unknown
• Subjects: Antarctica; Deception Island; Limnology; Phytoplankton; Volcanic lakes; abundance; alga; chlorophyll; community dynamics; freshwater environment; lacustrine environment; nanoplankton; population size; species richness; South Shetland Islands; algae; Bacillariophyceae; Chrysophyceae; Antarc*
• Online Access: https://hdl.handle.net/20.500.12110/paper_07224060_v30_n7_p849_Llames

This work constitutes the first floristic and ecological analysis of the phytoplankton community of a volcanic freshwater lake in Deception Island (62°57′S, 60°38′W, South Shetland Islands, Antarctica). The main limnological features and phytoplankton size fractions were analyzed. Samples were taken during the austral summer of 2002 at two opposite sites. According to ANOVA results performed with abiotic variables, no significant differences between sites were found. The phytoplankton community showed low algal species richness, with an important contribution of the tychoplanktonic taxa. In terms of species number, Bacillariophyceae was the dominant class. Autotrophic picoplankton registered the highest densities from the second sampling date onwards. Nanophytoplankton was represented by unidentified chrysophycean organisms, which showed different distribution patterns between sites. The net phytoplankton abundance remained low during the sampling period and was strongly correlated with chlorophyll a concentration. Both nutrient concentrations and chlorophyll a values indicated oligotrophic conditions. © 2007 Springer-Verlag.