Spring development of a Chlamydomonas population in Lake Nimet�n, a small humic forest lake in southern Finland

Abstract

Biomass development and vertical distribution of a Chlamydomonas population in a small humic forest lake was followed by daily sampling in May-June, 1984. Chlamydomonas dominated the phytoplankton spring bloom, forming 71% of the maximum phytoplankton biomass on 18 May. In early May the outflow rate was high and during the 24 hour period when the maximum rate of surface runoff was recorded (8 -9 May), 43%0 of the Chlamydomonas biomass was flushed out of the lake, which delayed the onset of biomass increase. When surface runoff had slowed down Chlamydomonas biomass started increasing and during wax of the population most cells were < 10 pm in diameter. Population maximum lasted for one day (18 May) and thereafter Chlamydomonas biomass decreased towards the end of the study. During wane of the population most cells were > 10 /Am in diameter. 157

Nitrogen-stimulated growth of algae in surface-water samples collected from freshwater kettle ponds of Cape Cod National Seashore (Massachusetts, USA)

“…Dissolved inorganic nitrogen (NH 4 and NO 3 /NO 2 ), total phosphorus (TP), and DIN:TP ratios in surface water for July 2010 (asterisks denote concentration was below the detection limit and where DIN:TP ratios were calculated using the detection limit itself; 'À' indicates where the N samples from Ryder Pond in August were lost and DIN:TP could not be calculated). (Dickman 1972;Simila¨1988;Doi et al 2004). C. acidophila is frequently reported from lakes that have similar chemical characteristics (ie, soft water, acidic, and oligotrophic) to CCNS kettle ponds (Reinertsen 1982;Laybourn-Parry et al 1991;Danilov and Ekelund 2001;Callieri et al 2002;Figure 2.…”