Response of acidophilic algae at pH 2 to concentrations of CO2, N and P

BEAMUD, G.; DIAZ, M.; BAFFICO, G.; PEDROZO, F.

Lahti, Finlandia

Congreso; XXIX Congreso de la Sociedad Internacional de Limnología (SIL); 2004

International Association of Theoretical and Applied Limnology

The rate of growth, photosynthetic CO2 and light-response curves of the acidophilic species isolated from Lake Caviahue and Agrio River at pH 2, were measured. Lab bioassays were performed to assess growth-rate and yield limitation by carbon, phosphorus and nitrogen. Chloridella sp growth was zero in the absence of CO2, but at air-equilibrium (360 ppm) had reached 86 to 95% of the saturated rate, which was achieved by 720 ppm. The addition of nitrogen changed the phytoplankton community structure: Chloridella sp and Keratoccocus raphidioides were replaced by Euglena mutabilis. Our results suggest that nitrogen may limit algae growth.