Epilithic algae in a glacial stream at Hope Bay, Antarctica

IZAGUIRRE, I., Y H. PIZARRO

POLAR BIOLOGY

SPRINGER

Año: 1998 vol. 19 p. 24 - 31

0722-4060

The epilithic algal community of a glacial stream of Hope Bay (Antarctica) was studied during the summer period of 1995. Major hydrological changes, which a€ected the main physical and chemical features, were observed in the stream according to the meltwater pulses. The enrichment of the stream by seabird inputs was evident from the high nutrient concentrations and their increase downstream. The presence of a snowbank in the middle reach produced a major discontinuity, in¯uencing the main variables analyzed. The stream showed a similar algal composition to other water courses of Hope Bay, with Prasiola crispa, Hydrurus foetidus, Phaeogloea mucosa and Phormidium fragile as the dominant species. Chlorophyll a concentrations taken from natural substrata (stones) ranged from un- detectable to 48.4 mg m)2, with the maximum concen- trations associated with algal mats dominated by Pra- siola crispa.Prasiola crispa, Hydrurus foetidus, Phaeogloea mucosa and Phormidium fragile as the dominant species. Chlorophyll a concentrations taken from natural substrata (stones) ranged from un- detectable to 48.4 mg m)2, with the maximum concen- trations associated with algal mats dominated by Pra- siola crispa., Phaeogloea mucosa and Phormidium fragile as the dominant species. Chlorophyll a concentrations taken from natural substrata (stones) ranged from un- detectable to 48.4 mg m)2, with the maximum concen- trations associated with algal mats dominated by Pra- siola crispa.a concentrations taken from natural substrata (stones) ranged from un- detectable to 48.4 mg m)2, with the maximum concen- trations associated with algal mats dominated by Pra- siola crispa.)2, with the maximum concen- trations associated with algal mats dominated by Pra- siola crispa.Pra- siola crispa..