Abstract
The dynamics of nutrients, such as phosphorus, nitrogen, and carbohydrates, during cyanobacteria cell lysis was investigated under darkness incubation in the laboratory. The cell lysis rate of cyanobacteria sampled from Lake Taihu was measured using an esterase assay. Based on particulate esterase activity, the calculated cyanobacteria lysis rate was 0.094 d^β1^. During 30 days of darkness incubation, Chlorophyll a concentration decreased from 56 ΞΌg L^β1^ to 2.0 ΞΌg L^β1^. Parallel to this, total particulate carbohydrate concentration decreased rapidly. The fluctuation of dissolved organic carbon concentration was a function of the production of nonβcarbohydrate by cyanobacteria and the decomposition of carbohydrate by bacteria. Total dissolved carbohydrates and dissolved polysaccharides concentrations showed a similar pattern, declining at the beginning of the experiment and keeping relatively stable, thereafter. In contrast, the concentration of dissolved monosaccharides remained constant during the entire process. The concentrations of NH~4~^+^ and PO~4~^3β^ increased at the early stage, and then decreased afterwards. A gradual decrease in NO~3~^β^ concentration after day 8 indicated that anaerobic conditions might be produced during the cell lysis process. The present results demonstrated cyanobacteria cell lysis has a big influence on the nutrient status of the surrounding water. (Β© 2010 WILEYβVCH Verlag GmbH & Co. KGaA, Weinheim)